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In this paper, first, the ship tracking system was optimized using the Bi-YOLO network based on the C2f_BiFormer module and the OC-SORT algorithms. Second, to extract the visual trajectory of the target ship without a reference object, an absolute position estimation method based on binocular stereo vision attitude information was proposed. Then, a perception data fusion framework based on ship spatio-temporal trajectory features (ST-TF) was proposed to match GPS-based ship information with corresponding visual target information. Finally, AR technology was integrated to fuse multi-source perceptual information into the real-world navigation view. Experimental results demonstrate that the proposed method achieves a mAP0.5:0.95 of 79.6% under challenging scenarios such as low resolution, noise interference, and low-light conditions. Moreover, in the presence of the nonlinear motion of the own ship, the average relative position error of target ship visual measurements is maintained below 8%, achieving accurate absolute position estimation without reference objects. Compared to existing navigation assistance, the AR-based navigation assistance system, which utilizes ship ST-TF-based perception data fusion mechanism, enhances ship traffic situational awareness and provides reliable decision-making support to further ensure the safety of ship navigation.</description> <pubDate>2025-02-16</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 366: Target Ship Recognition and Tracking with Data Fusion Based on Bi-YOLO and OC-SORT Algorithms for Enhancing Ship Navigation Assistance Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/366">doi: 10.3390/jmse13020366</a> Authors: Shuai Chen Miao Gao Peiru Shi Xi Zeng Anmin Zhang With the ever-increasing volume of maritime traffic, the risks of ship navigation are becoming more significant, making the use of advanced multi-source perception strategies and AI technologies indispensable for obtaining information about ship navigation status. In this paper, first, the ship tracking system was optimized using the Bi-YOLO network based on the C2f_BiFormer module and the OC-SORT algorithms. Second, to extract the visual trajectory of the target ship without a reference object, an absolute position estimation method based on binocular stereo vision attitude information was proposed. Then, a perception data fusion framework based on ship spatio-temporal trajectory features (ST-TF) was proposed to match GPS-based ship information with corresponding visual target information. Finally, AR technology was integrated to fuse multi-source perceptual information into the real-world navigation view. Experimental results demonstrate that the proposed method achieves a mAP0.5:0.95 of 79.6% under challenging scenarios such as low resolution, noise interference, and low-light conditions. Moreover, in the presence of the nonlinear motion of the own ship, the average relative position error of target ship visual measurements is maintained below 8%, achieving accurate absolute position estimation without reference objects. Compared to existing navigation assistance, the AR-based navigation assistance system, which utilizes ship ST-TF-based perception data fusion mechanism, enhances ship traffic situational awareness and provides reliable decision-making support to further ensure the safety of ship navigation. ]]></content:encoded> <dc:title>Target Ship Recognition and Tracking with Data Fusion Based on Bi-YOLO and OC-SORT Algorithms for Enhancing Ship Navigation Assistance</dc:title> <dc:creator>Shuai Chen</dc:creator> <dc:creator>Miao Gao</dc:creator> <dc:creator>Peiru Shi</dc:creator> <dc:creator>Xi Zeng</dc:creator> <dc:creator>Anmin Zhang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020366</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-16</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-16</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>366</prism:startingPage> <prism:doi>10.3390/jmse13020366</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/366</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/365"> <title>JMSE, Vol. 13, Pages 365: Target-Defense Games with One or Two Unmanned Surface Vehicles Defending an Island: A Geometric Analytical Approach</title> <link>https://www.mdpi.com/2077-1312/13/2/365</link> <description>This paper considers a target-defense game in an open area with one or two defenders as well as an intruder. The intruder endeavors to reach the boundary of the island, while the defenders strive to prevent that by capturing the intruder through contact. Islands, as closed areas, restrict the free movement of the defenders, since the defenders&amp;mdash;represented by USVs&amp;mdash;cannot traverse the target area directly. First, we are concerned with the barrier, which is the boundary of the winning zones, taking into account the impact of the target. For the initial states lying in the defenders&amp;rsquo; winning zone, there exists a strategy for the defenders to intercept the intruder regardless of the intruder&amp;rsquo;s best effort, while for the initial states lying in the intruder&amp;rsquo;s winning zone, the intruder can always invade successfully. We propose a geometric method to construct the barrier analytically for two kinds of speed ratios. Then, by taking index functions into consideration, we present optimal strategies for the players after constructing the dominance regions when their initial states lie in different winning zones. Simulation results verify the effectiveness of the proposed method. This study can be extended to scenarios involving multiple defenders.</description> <pubDate>2025-02-16</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 365: Target-Defense Games with One or Two Unmanned Surface Vehicles Defending an Island: A Geometric Analytical Approach Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/365">doi: 10.3390/jmse13020365</a> Authors: Keyang Wang Yintao Wang Qi Sun This paper considers a target-defense game in an open area with one or two defenders as well as an intruder. The intruder endeavors to reach the boundary of the island, while the defenders strive to prevent that by capturing the intruder through contact. Islands, as closed areas, restrict the free movement of the defenders, since the defenders&amp;mdash;represented by USVs&amp;mdash;cannot traverse the target area directly. First, we are concerned with the barrier, which is the boundary of the winning zones, taking into account the impact of the target. For the initial states lying in the defenders&amp;rsquo; winning zone, there exists a strategy for the defenders to intercept the intruder regardless of the intruder&amp;rsquo;s best effort, while for the initial states lying in the intruder&amp;rsquo;s winning zone, the intruder can always invade successfully. We propose a geometric method to construct the barrier analytically for two kinds of speed ratios. Then, by taking index functions into consideration, we present optimal strategies for the players after constructing the dominance regions when their initial states lie in different winning zones. Simulation results verify the effectiveness of the proposed method. This study can be extended to scenarios involving multiple defenders. ]]></content:encoded> <dc:title>Target-Defense Games with One or Two Unmanned Surface Vehicles Defending an Island: A Geometric Analytical Approach</dc:title> <dc:creator>Keyang Wang</dc:creator> <dc:creator>Yintao Wang</dc:creator> <dc:creator>Qi Sun</dc:creator> <dc:identifier>doi: 10.3390/jmse13020365</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-16</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-16</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>365</prism:startingPage> <prism:doi>10.3390/jmse13020365</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/365</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/364"> <title>JMSE, Vol. 13, Pages 364: Passivity-Based Sliding Mode Control for the Robust Trajectory Tracking of Unmanned Surface Vessels Under External Disturbances and Model Uncertainty</title> <link>https://www.mdpi.com/2077-1312/13/2/364</link> <description>This study uses a port-Hamiltonian framework to address trajectory tracking control for unmanned surface vessels (USVs) under unknown disturbances. A passivity-based sliding mode controller is designed, integrating adaptive disturbance estimation and an RBFNN-based uncertainty estimator. Stability is rigorously proven, and simulations confirm superior tracking performance, strong disturbance rejection, and accurate uncertainty estimation.</description> <pubDate>2025-02-16</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 364: Passivity-Based Sliding Mode Control for the Robust Trajectory Tracking of Unmanned Surface Vessels Under External Disturbances and Model Uncertainty Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/364">doi: 10.3390/jmse13020364</a> Authors: Luke Ma Siyi Pang Yao He Yongxin Wu Yanjun Li Weijun Zhou This study uses a port-Hamiltonian framework to address trajectory tracking control for unmanned surface vessels (USVs) under unknown disturbances. A passivity-based sliding mode controller is designed, integrating adaptive disturbance estimation and an RBFNN-based uncertainty estimator. Stability is rigorously proven, and simulations confirm superior tracking performance, strong disturbance rejection, and accurate uncertainty estimation. ]]></content:encoded> <dc:title>Passivity-Based Sliding Mode Control for the Robust Trajectory Tracking of Unmanned Surface Vessels Under External Disturbances and Model Uncertainty</dc:title> <dc:creator>Luke Ma</dc:creator> <dc:creator>Siyi Pang</dc:creator> <dc:creator>Yao He</dc:creator> <dc:creator>Yongxin Wu</dc:creator> <dc:creator>Yanjun Li</dc:creator> <dc:creator>Weijun Zhou</dc:creator> <dc:identifier>doi: 10.3390/jmse13020364</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-16</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-16</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>364</prism:startingPage> <prism:doi>10.3390/jmse13020364</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/364</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/363"> <title>JMSE, Vol. 13, Pages 363: Investigation of Interfacial Behavior in Density Current Collisions</title> <link>https://www.mdpi.com/2077-1312/13/2/363</link> <description>This study provides a comprehensive examination of colliding density currents with a range of density differences from 1% to 4%, using controlled laboratory experiments with saltwater and freshwater. The research reveals that when density currents collide, they generate internal bore, with the denser fluid flowing consistently beneath the lighter fluid. A significant finding is the temporary stalling and oscillatory motion of the current fronts during collisions, which is linked to a partial dissipation of kinetic energy and the subsequent formation of internal waves. Numerical simulations showed close agreement with experimental observations, reproducing the location of the tidal fronts well and verifying the accuracy of the hydrodynamic model used. Moreover, the study demonstrates that collisions between fluids with different densities notably enhance diffusion and mixing efficiency. This has important implications for environmental science, particularly in understanding and predicting density-driven fluid dynamics in aquatic systems such as estuaries and coastal zones. The enhanced mixing efficiency observed could be crucial for applications in environmental and pollution control, offering insights into material transport and pollutant dispersion.</description> <pubDate>2025-02-16</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 363: Investigation of Interfacial Behavior in Density Current Collisions Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/363">doi: 10.3390/jmse13020363</a> Authors: Jinichi Koue This study provides a comprehensive examination of colliding density currents with a range of density differences from 1% to 4%, using controlled laboratory experiments with saltwater and freshwater. The research reveals that when density currents collide, they generate internal bore, with the denser fluid flowing consistently beneath the lighter fluid. A significant finding is the temporary stalling and oscillatory motion of the current fronts during collisions, which is linked to a partial dissipation of kinetic energy and the subsequent formation of internal waves. Numerical simulations showed close agreement with experimental observations, reproducing the location of the tidal fronts well and verifying the accuracy of the hydrodynamic model used. Moreover, the study demonstrates that collisions between fluids with different densities notably enhance diffusion and mixing efficiency. This has important implications for environmental science, particularly in understanding and predicting density-driven fluid dynamics in aquatic systems such as estuaries and coastal zones. The enhanced mixing efficiency observed could be crucial for applications in environmental and pollution control, offering insights into material transport and pollutant dispersion. ]]></content:encoded> <dc:title>Investigation of Interfacial Behavior in Density Current Collisions</dc:title> <dc:creator>Jinichi Koue</dc:creator> <dc:identifier>doi: 10.3390/jmse13020363</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-16</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-16</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>363</prism:startingPage> <prism:doi>10.3390/jmse13020363</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/363</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/362"> <title>JMSE, Vol. 13, Pages 362: Novel Polarization Construction Method and Synchronization Algorithm for Underwater Acoustic Channel Under T-Distribution Noise Environment</title> <link>https://www.mdpi.com/2077-1312/13/2/362</link> <description>Abstract:&amp;nbsp;Underwater acoustic channel (UWAC) is characterized by significant multipath effects, strong time-varying properties and complex noise environments, which make achieving high-rate and reliable underwater communication a formidable task. To address the above adverse challenges, this study first presents a novel, robust and efficient polar code construction (NREPCC) method using the base-adversarial polarization weight (BPW) algorithm tailored for typical ocean channel models, including invariable sound velocity gradient (ISVG) channels, negative sound velocity gradient (NSVG) channels, and positive sound velocity gradient (PSVG) channels. Subsequently, a robust and reliable polar-coded UWAC system model based on the orthogonal frequency division multiplexing (OFDM) technique is designed using the -distribution noise model in conjunction with real sea noise data fitting. Then, an enhanced time synchronization and packet detection algorithm based on -distribution is proposed for the performance optimization of the polar-coded UWAC OFDM system. Finally, extensive numerical simulation results confirm the excellent performance of the proposed NREPCC method and polar-coded UWAC OFDM system under a variety of channel conditions. Specifically, the NREPCC method outperforms low-density parity-check (LDPC) codes by approximately 0.5~1 dB in PSVG and ISVG channels while maintaining lower encoding and decoding complexity. Moreover, the robustness of the NREPCC method under -distribution noise with varying degrees of freedom is rigorously validated, which renders vital technical support for the design of high-precision and high-robustness UWAC systems.</description> <pubDate>2025-02-15</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 362: Novel Polarization Construction Method and Synchronization Algorithm for Underwater Acoustic Channel Under T-Distribution Noise Environment Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/362">doi: 10.3390/jmse13020362</a> Authors: Jiangfeng Xian Zhisheng Li Huafeng Wu Weijun Wang Xinqiang Chen Xiaojun Mei Yuanyuan Zhang Bing Han Junling Ma Abstract:&amp;nbsp;Underwater acoustic channel (UWAC) is characterized by significant multipath effects, strong time-varying properties and complex noise environments, which make achieving high-rate and reliable underwater communication a formidable task. To address the above adverse challenges, this study first presents a novel, robust and efficient polar code construction (NREPCC) method using the base-adversarial polarization weight (BPW) algorithm tailored for typical ocean channel models, including invariable sound velocity gradient (ISVG) channels, negative sound velocity gradient (NSVG) channels, and positive sound velocity gradient (PSVG) channels. Subsequently, a robust and reliable polar-coded UWAC system model based on the orthogonal frequency division multiplexing (OFDM) technique is designed using the -distribution noise model in conjunction with real sea noise data fitting. Then, an enhanced time synchronization and packet detection algorithm based on -distribution is proposed for the performance optimization of the polar-coded UWAC OFDM system. Finally, extensive numerical simulation results confirm the excellent performance of the proposed NREPCC method and polar-coded UWAC OFDM system under a variety of channel conditions. Specifically, the NREPCC method outperforms low-density parity-check (LDPC) codes by approximately 0.5~1 dB in PSVG and ISVG channels while maintaining lower encoding and decoding complexity. Moreover, the robustness of the NREPCC method under -distribution noise with varying degrees of freedom is rigorously validated, which renders vital technical support for the design of high-precision and high-robustness UWAC systems. ]]></content:encoded> <dc:title>Novel Polarization Construction Method and Synchronization Algorithm for Underwater Acoustic Channel Under T-Distribution Noise Environment</dc:title> <dc:creator>Jiangfeng Xian</dc:creator> <dc:creator>Zhisheng Li</dc:creator> <dc:creator>Huafeng Wu</dc:creator> <dc:creator>Weijun Wang</dc:creator> <dc:creator>Xinqiang Chen</dc:creator> <dc:creator>Xiaojun Mei</dc:creator> <dc:creator>Yuanyuan Zhang</dc:creator> <dc:creator>Bing Han</dc:creator> <dc:creator>Junling Ma</dc:creator> <dc:identifier>doi: 10.3390/jmse13020362</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-15</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-15</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>362</prism:startingPage> <prism:doi>10.3390/jmse13020362</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/362</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/357"> <title>JMSE, Vol. 13, Pages 357: Enhanced Continental Weathering and Intense Upwelling Drove the Deposition of Organic-Rich Shales in the Late Permian Dalong Formation, South China</title> <link>https://www.mdpi.com/2077-1312/13/2/357</link> <description>Marine black shales are important to geologists, because they are not only potential sources and reservoir rocks for shale gas/oil, but also, their deposition could influence the climatic and oceanic environments. Here, a detailed study of the shales in the Dalong Formation in South China was conducted to understand the changes in continental weathering and upwelling and their influences on organic matter accumulation in the late Permian. The results revealed that the deposition of the Dalong and Daye Formations could be divided into five stages, with the highest TOC values (&amp;gt;2%) being observed in stages 2 and 4, intermediate TOCs (~1% to 2%) being observed in stages 1 and 3, and the lowest TOC values (&amp;lt;1%) being observed in stage 5. This study attributed the enhanced organic matter accumulation in stages 2 and 4 to enhanced continental weathering (high CIA values and &amp;delta;26Mg values) and intense upwelling (high Mo/TOC ratios and low &amp;delta;13Corg and CoEF &amp;times; MnEF values), both of which contributed to high primary productivity and increased anoxia of the bottom waters, further leading to the accumulation of organic matter. Overall, both enhanced continental weathering and upwelling contributed to the development of anoxia, even euxinia, of the seawater and further triggered an end-Permian mass extinction (EPME).</description> <pubDate>2025-02-15</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 357: Enhanced Continental Weathering and Intense Upwelling Drove the Deposition of Organic-Rich Shales in the Late Permian Dalong Formation, South China Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/357">doi: 10.3390/jmse13020357</a> Authors: Yin Gong Yiming Li Peng Yang Meng Xiang Zhou Zhou Zhongquan Zhang Xing Niu Xiangrong Yang Marine black shales are important to geologists, because they are not only potential sources and reservoir rocks for shale gas/oil, but also, their deposition could influence the climatic and oceanic environments. Here, a detailed study of the shales in the Dalong Formation in South China was conducted to understand the changes in continental weathering and upwelling and their influences on organic matter accumulation in the late Permian. The results revealed that the deposition of the Dalong and Daye Formations could be divided into five stages, with the highest TOC values (&amp;gt;2%) being observed in stages 2 and 4, intermediate TOCs (~1% to 2%) being observed in stages 1 and 3, and the lowest TOC values (&amp;lt;1%) being observed in stage 5. This study attributed the enhanced organic matter accumulation in stages 2 and 4 to enhanced continental weathering (high CIA values and &amp;delta;26Mg values) and intense upwelling (high Mo/TOC ratios and low &amp;delta;13Corg and CoEF &amp;times; MnEF values), both of which contributed to high primary productivity and increased anoxia of the bottom waters, further leading to the accumulation of organic matter. Overall, both enhanced continental weathering and upwelling contributed to the development of anoxia, even euxinia, of the seawater and further triggered an end-Permian mass extinction (EPME). ]]></content:encoded> <dc:title>Enhanced Continental Weathering and Intense Upwelling Drove the Deposition of Organic-Rich Shales in the Late Permian Dalong Formation, South China</dc:title> <dc:creator>Yin Gong</dc:creator> <dc:creator>Yiming Li</dc:creator> <dc:creator>Peng Yang</dc:creator> <dc:creator>Meng Xiang</dc:creator> <dc:creator>Zhou Zhou</dc:creator> <dc:creator>Zhongquan Zhang</dc:creator> <dc:creator>Xing Niu</dc:creator> <dc:creator>Xiangrong Yang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020357</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-15</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-15</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>357</prism:startingPage> <prism:doi>10.3390/jmse13020357</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/357</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/359"> <title>JMSE, Vol. 13, Pages 359: Modeling Bottom Dissolved Oxygen on the East China Sea Shelf Using Interpretable Machine Learning</title> <link>https://www.mdpi.com/2077-1312/13/2/359</link> <description>Monitoring bottom dissolved oxygen (DO) is crucial for understanding hypoxia, a threat to marine ecosystems and fisheries. However, traditional observations are limited in spatiotemporal coverage, while numerical models consume tremendous computing resources. This study develops an interpretable machine learning framework to simulate the bottom DO distribution on the East China Sea (ECS) shelf and explore its potential driving mechanisms. By integrating remote sensing, in situ observations, and numerical model outputs, the framework generates high-resolution (4 km) DO estimates from 1998 to 2024. Validation against independent datasets confirms the improved accuracy and spatial resolution, with an RMSE below 1 mg/L. The results reveal a persistent decline in DO, strongly linked to rising sea surface temperature (SST), underscoring the role of surface warming in bottom water deoxygenation. Model interpretability further identifies the SST and bathymetry as key factors. This framework provides a robust tool for assessing bottom DO trends, hypoxia, and their ecological impacts, supporting future monitoring and management of the ECS shelf.</description> <pubDate>2025-02-15</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 359: Modeling Bottom Dissolved Oxygen on the East China Sea Shelf Using Interpretable Machine Learning Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/359">doi: 10.3390/jmse13020359</a> Authors: Chengqing Zhang Qicheng Meng Xiao Ma Anqi Liu Feng Zhou Monitoring bottom dissolved oxygen (DO) is crucial for understanding hypoxia, a threat to marine ecosystems and fisheries. However, traditional observations are limited in spatiotemporal coverage, while numerical models consume tremendous computing resources. This study develops an interpretable machine learning framework to simulate the bottom DO distribution on the East China Sea (ECS) shelf and explore its potential driving mechanisms. By integrating remote sensing, in situ observations, and numerical model outputs, the framework generates high-resolution (4 km) DO estimates from 1998 to 2024. Validation against independent datasets confirms the improved accuracy and spatial resolution, with an RMSE below 1 mg/L. The results reveal a persistent decline in DO, strongly linked to rising sea surface temperature (SST), underscoring the role of surface warming in bottom water deoxygenation. Model interpretability further identifies the SST and bathymetry as key factors. This framework provides a robust tool for assessing bottom DO trends, hypoxia, and their ecological impacts, supporting future monitoring and management of the ECS shelf. ]]></content:encoded> <dc:title>Modeling Bottom Dissolved Oxygen on the East China Sea Shelf Using Interpretable Machine Learning</dc:title> <dc:creator>Chengqing Zhang</dc:creator> <dc:creator>Qicheng Meng</dc:creator> <dc:creator>Xiao Ma</dc:creator> <dc:creator>Anqi Liu</dc:creator> <dc:creator>Feng Zhou</dc:creator> <dc:identifier>doi: 10.3390/jmse13020359</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-15</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-15</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>359</prism:startingPage> <prism:doi>10.3390/jmse13020359</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/359</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/361"> <title>JMSE, Vol. 13, Pages 361: Impact of Ocean Sound Speed Horizontal Gradient on Global Navigation Satellite System&ndash;Acoustic Precise Seafloor Positioning</title> <link>https://www.mdpi.com/2077-1312/13/2/361</link> <description>Global Navigation Satellite System&amp;ndash;Acoustic ranging (GNSS-A) technology can achieve centimeter-level seafloor positioning. However, the horizontal gradient of ocean sound speed limits the seafloor positioning accuracy of GNSS-A. This paper evaluates the impact of ocean sound speed horizontal gradients on GNSS-A seafloor positioning utilizing Bayesian estimation. Publicly available GNSS-A datasets from 2012 to 2021 were processed using strategies with and without estimating sound speed horizontal gradients. The comparison of results demonstrates that the ocean sound speed horizontal gradient has a significant impact on horizontal positioning but a smaller impact on vertical positioning. The mean root mean square (RMS) of horizontal positioning differences for both strategies is 0.12 m, with a maximum of 0.19 m. The mean RMS of vertical positioning differences is 0.014 m, with a maximum of 0.021 m. The mean RMS of station velocity differences is 0.004 m/a and 0.008 m/a in the east and the north components, respectively, with a maximum RMS of 0.01 m/a in the horizontal component. The vertical station velocity differences for both strategies are relatively small, with a mean RMS of 0.002 m/a and a maximum RMS of 0.003 m/a. The mean RMS difference in sound speed correction for both strategies is 0.01 m/s. The sound speed horizontal gradient is larger in the shallow portion than in the deep portion. In the shallow portion, the mean RMS is 0.052 m/s/km and 0.072 m/s/km in the east and north component, respectively. In the deep portion, the mean RMS is 0.023 m/s/km and 0.024 m/s/km in the east and north components, respectively. The sound speed horizontal gradient varies significantly at different locations due to the marine environment discrepancies, which require refined GNSS-A processing to improve seafloor positioning accuracy.</description> <pubDate>2025-02-15</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 361: Impact of Ocean Sound Speed Horizontal Gradient on Global Navigation Satellite System&ndash;Acoustic Precise Seafloor Positioning Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/361">doi: 10.3390/jmse13020361</a> Authors: Yang Liu Tianjie Shi Yanxiong Liu Shengli Wang Guanxu Chen Menghao Li Qiuhua Tang Yikai Feng Global Navigation Satellite System&amp;ndash;Acoustic ranging (GNSS-A) technology can achieve centimeter-level seafloor positioning. However, the horizontal gradient of ocean sound speed limits the seafloor positioning accuracy of GNSS-A. This paper evaluates the impact of ocean sound speed horizontal gradients on GNSS-A seafloor positioning utilizing Bayesian estimation. Publicly available GNSS-A datasets from 2012 to 2021 were processed using strategies with and without estimating sound speed horizontal gradients. The comparison of results demonstrates that the ocean sound speed horizontal gradient has a significant impact on horizontal positioning but a smaller impact on vertical positioning. The mean root mean square (RMS) of horizontal positioning differences for both strategies is 0.12 m, with a maximum of 0.19 m. The mean RMS of vertical positioning differences is 0.014 m, with a maximum of 0.021 m. The mean RMS of station velocity differences is 0.004 m/a and 0.008 m/a in the east and the north components, respectively, with a maximum RMS of 0.01 m/a in the horizontal component. The vertical station velocity differences for both strategies are relatively small, with a mean RMS of 0.002 m/a and a maximum RMS of 0.003 m/a. The mean RMS difference in sound speed correction for both strategies is 0.01 m/s. The sound speed horizontal gradient is larger in the shallow portion than in the deep portion. In the shallow portion, the mean RMS is 0.052 m/s/km and 0.072 m/s/km in the east and north component, respectively. In the deep portion, the mean RMS is 0.023 m/s/km and 0.024 m/s/km in the east and north components, respectively. The sound speed horizontal gradient varies significantly at different locations due to the marine environment discrepancies, which require refined GNSS-A processing to improve seafloor positioning accuracy. ]]></content:encoded> <dc:title>Impact of Ocean Sound Speed Horizontal Gradient on Global Navigation Satellite System&amp;ndash;Acoustic Precise Seafloor Positioning</dc:title> <dc:creator>Yang Liu</dc:creator> <dc:creator>Tianjie Shi</dc:creator> <dc:creator>Yanxiong Liu</dc:creator> <dc:creator>Shengli Wang</dc:creator> <dc:creator>Guanxu Chen</dc:creator> <dc:creator>Menghao Li</dc:creator> <dc:creator>Qiuhua Tang</dc:creator> <dc:creator>Yikai Feng</dc:creator> <dc:identifier>doi: 10.3390/jmse13020361</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-15</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-15</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>361</prism:startingPage> <prism:doi>10.3390/jmse13020361</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/361</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/360"> <title>JMSE, Vol. 13, Pages 360: Mooring Failure Analysis of Semisubmersible Floating Offshore Wind Turbines Considering Mooring Redundancy at Each Azimuth Angle</title> <link>https://www.mdpi.com/2077-1312/13/2/360</link> <description>Semisubmersible floating structures are becoming the predominant understructure type for floating offshore wind turbines (FOWTs) worldwide. As FOWTs are erected far away from land and in deep seas, they inevitably suffer violent and complicated sea conditions, including extreme waves and winds. Mooring lines are the representative flexible members of the whole structure and are likely to incur damage due to years of impact, corrosion, or fatigue. To improve mooring redundancy at each azimuth angle around a wind turbine, a group of mooring lines are configured in the same direction instead of just one mooring line. This study focuses on the mooring failure problems that would probably occur in a realistic redundant mooring system of a semisubmersible FOWT, and the worst residual mooring layout is considered. An FOWT numerical model with a 3 &amp;times; 3 mooring system is established in terms of 3D potential flow and BEM (blade element momentum) theories, and aero-hydro floating-body mooring coupled analyses are performed to discuss the subsequent time histories of dynamic responses after different types of mooring failure. As under extreme failure conditions, the final horizontal offsets of the structure and the layout of the residual mooring system are evaluated under still water, design, and extreme environmental conditions. The results show that the transient tension in up-wave mooring lines can reach more than 12,000 kN under extreme environmental conditions, inducing further failure of the whole chain group. Then, a deflection angle of 60&amp;deg; may occur on the residual laid chain, which may bring about dangerous anchor dragging.</description> <pubDate>2025-02-15</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 360: Mooring Failure Analysis of Semisubmersible Floating Offshore Wind Turbines Considering Mooring Redundancy at Each Azimuth Angle Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/360">doi: 10.3390/jmse13020360</a> Authors: Shuai Hao Xuning Zhang Yang Yu Bin Wang Xingdao Bo Semisubmersible floating structures are becoming the predominant understructure type for floating offshore wind turbines (FOWTs) worldwide. As FOWTs are erected far away from land and in deep seas, they inevitably suffer violent and complicated sea conditions, including extreme waves and winds. Mooring lines are the representative flexible members of the whole structure and are likely to incur damage due to years of impact, corrosion, or fatigue. To improve mooring redundancy at each azimuth angle around a wind turbine, a group of mooring lines are configured in the same direction instead of just one mooring line. This study focuses on the mooring failure problems that would probably occur in a realistic redundant mooring system of a semisubmersible FOWT, and the worst residual mooring layout is considered. An FOWT numerical model with a 3 &amp;times; 3 mooring system is established in terms of 3D potential flow and BEM (blade element momentum) theories, and aero-hydro floating-body mooring coupled analyses are performed to discuss the subsequent time histories of dynamic responses after different types of mooring failure. As under extreme failure conditions, the final horizontal offsets of the structure and the layout of the residual mooring system are evaluated under still water, design, and extreme environmental conditions. The results show that the transient tension in up-wave mooring lines can reach more than 12,000 kN under extreme environmental conditions, inducing further failure of the whole chain group. Then, a deflection angle of 60&amp;deg; may occur on the residual laid chain, which may bring about dangerous anchor dragging. ]]></content:encoded> <dc:title>Mooring Failure Analysis of Semisubmersible Floating Offshore Wind Turbines Considering Mooring Redundancy at Each Azimuth Angle</dc:title> <dc:creator>Shuai Hao</dc:creator> <dc:creator>Xuning Zhang</dc:creator> <dc:creator>Yang Yu</dc:creator> <dc:creator>Bin Wang</dc:creator> <dc:creator>Xingdao Bo</dc:creator> <dc:identifier>doi: 10.3390/jmse13020360</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-15</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-15</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>360</prism:startingPage> <prism:doi>10.3390/jmse13020360</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/360</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/358"> <title>JMSE, Vol. 13, Pages 358: Bacterial Diversity Associated with Millepora alcicornis, Phyllogorgia dilatata and Mussismilia harttii Collected from Two Distinct Corals Reefs on the Brazilian Coast</title> <link>https://www.mdpi.com/2077-1312/13/2/358</link> <description>Corals can be considered holobiont organisms, since they have an important symbiotic relationship with microbial communities such as zooxanthellae, bacteria, Archaea, fungi and viruses. It is important to understand how those microbial communities influence the health of the corals and how environmental conditions could affect them. The present study aimed to describe the bacterial communities associated with three Brazilian coral species, Millepora alcicornis, Mussismilia harttii and Phyllogorgia dilatata, by a culture-independent method, using 16S rRNA gene sequencing. The corals were collected from two distinct coral reefs: Recife de Fora, in Bahia (BA) and B&amp;uacute;zios, in Rio de Janeiro (RJ). The phylum Proteobacteria showed the highest relative abundance in most corals and sites. The bacterial compositions of these three corals from the two sample sites were very distinct from each other, not presenting similarities in coral species or related to sampling site. In M. alcicornes/RJ, the most abundant class was Gammaproteobacteria, order Piscirickettsiales, while the same species collected in BA showed unassigned Gammaproteobacteria, and Vibrionaceae was the second most abundant family. M. harttii/BA presented the most distinct bacterial phylum composition with 16 phyla (26% Proteobacteria, 16% Chloroflexi, 12% Acidobacteriota).</description> <pubDate>2025-02-15</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 358: Bacterial Diversity Associated with Millepora alcicornis, Phyllogorgia dilatata and Mussismilia harttii Collected from Two Distinct Corals Reefs on the Brazilian Coast Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/358">doi: 10.3390/jmse13020358</a> Authors: Rosiane Andrade da Costa Maria Wanna Figueiredo Henrique Fragoso dos Santos Ot谩vio Henrique Bezerra Pinto Cristine Chaves Barreto S茅rgio Amorim de Alencar Simoni Campos Dias Corals can be considered holobiont organisms, since they have an important symbiotic relationship with microbial communities such as zooxanthellae, bacteria, Archaea, fungi and viruses. It is important to understand how those microbial communities influence the health of the corals and how environmental conditions could affect them. The present study aimed to describe the bacterial communities associated with three Brazilian coral species, Millepora alcicornis, Mussismilia harttii and Phyllogorgia dilatata, by a culture-independent method, using 16S rRNA gene sequencing. The corals were collected from two distinct coral reefs: Recife de Fora, in Bahia (BA) and B&amp;uacute;zios, in Rio de Janeiro (RJ). The phylum Proteobacteria showed the highest relative abundance in most corals and sites. The bacterial compositions of these three corals from the two sample sites were very distinct from each other, not presenting similarities in coral species or related to sampling site. In M. alcicornes/RJ, the most abundant class was Gammaproteobacteria, order Piscirickettsiales, while the same species collected in BA showed unassigned Gammaproteobacteria, and Vibrionaceae was the second most abundant family. M. harttii/BA presented the most distinct bacterial phylum composition with 16 phyla (26% Proteobacteria, 16% Chloroflexi, 12% Acidobacteriota). ]]></content:encoded> <dc:title>Bacterial Diversity Associated with Millepora alcicornis, Phyllogorgia dilatata and Mussismilia harttii Collected from Two Distinct Corals Reefs on the Brazilian Coast</dc:title> <dc:creator>Rosiane Andrade da Costa</dc:creator> <dc:creator>Maria Wanna Figueiredo</dc:creator> <dc:creator>Henrique Fragoso dos Santos</dc:creator> <dc:creator>Ot谩vio Henrique Bezerra Pinto</dc:creator> <dc:creator>Cristine Chaves Barreto</dc:creator> <dc:creator>S茅rgio Amorim de Alencar</dc:creator> <dc:creator>Simoni Campos Dias</dc:creator> <dc:identifier>doi: 10.3390/jmse13020358</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-15</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-15</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>358</prism:startingPage> <prism:doi>10.3390/jmse13020358</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/358</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/356"> <title>JMSE, Vol. 13, Pages 356: Multi-View and Multi-Type Feature Fusion Rotor Biofouling Recognition Method for Tidal Stream Turbine</title> <link>https://www.mdpi.com/2077-1312/13/2/356</link> <description>Power generation is affected and structural instability may occur when biofouling attaches to the rotor of tidal stream turbines (TSTs). Image signals are used to identify biofouling for biofouling recognition, thus achieving on-demand maintenance, optimizing power generation efficiency, and minimizing maintenance costs. However, image signals are sensitive to background interferences, and underwater targets blend with the water background, making it difficult to extract target features. Changes in water turbidity can affect the effectiveness of image signal biofouling recognition, which can lead to reduced recognition accuracy. In order to solve these problems, a multi-view and multi-type feature fusion (MVTFF) method is proposed to recognize rotor biofouling on TSTs for applications in TST operation and maintenance. (1) Key boundary and semantic information are captured to solve the problem of background feature interference by comparing and fusing the extracted multi-view features. (2) The local geometric description and dependency are obtained by integrating contour features into multi-view features to address the issue of the target mixing with water. The mIoU, mPA, Precision, and Recall of the experimental results show that the method achieves superior recognition performance on TST datasets with different turbidity levels.</description> <pubDate>2025-02-15</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 356: Multi-View and Multi-Type Feature Fusion Rotor Biofouling Recognition Method for Tidal Stream Turbine Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/356">doi: 10.3390/jmse13020356</a> Authors: Haoran Xu Dingding Yang Tianzhen Wang Mohamed Benbouzid Power generation is affected and structural instability may occur when biofouling attaches to the rotor of tidal stream turbines (TSTs). Image signals are used to identify biofouling for biofouling recognition, thus achieving on-demand maintenance, optimizing power generation efficiency, and minimizing maintenance costs. However, image signals are sensitive to background interferences, and underwater targets blend with the water background, making it difficult to extract target features. Changes in water turbidity can affect the effectiveness of image signal biofouling recognition, which can lead to reduced recognition accuracy. In order to solve these problems, a multi-view and multi-type feature fusion (MVTFF) method is proposed to recognize rotor biofouling on TSTs for applications in TST operation and maintenance. (1) Key boundary and semantic information are captured to solve the problem of background feature interference by comparing and fusing the extracted multi-view features. (2) The local geometric description and dependency are obtained by integrating contour features into multi-view features to address the issue of the target mixing with water. The mIoU, mPA, Precision, and Recall of the experimental results show that the method achieves superior recognition performance on TST datasets with different turbidity levels. ]]></content:encoded> <dc:title>Multi-View and Multi-Type Feature Fusion Rotor Biofouling Recognition Method for Tidal Stream Turbine</dc:title> <dc:creator>Haoran Xu</dc:creator> <dc:creator>Dingding Yang</dc:creator> <dc:creator>Tianzhen Wang</dc:creator> <dc:creator>Mohamed Benbouzid</dc:creator> <dc:identifier>doi: 10.3390/jmse13020356</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-15</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-15</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>356</prism:startingPage> <prism:doi>10.3390/jmse13020356</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/356</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/355"> <title>JMSE, Vol. 13, Pages 355: Combined Motion Compensation Method for Long Synthetic Aperture Radar Based on Subaperture Processing</title> <link>https://www.mdpi.com/2077-1312/13/2/355</link> <description>Long synthetic aperture radar (SAR) offers the advantage of achieving higher resolution by utilizing longer synthetic aperture times, which makes it a promising technology for ocean observation in the future. However, compared to SAR systems with shorter synthetic aperture times, it suffers more severely from issues such as image defocusing, blurring and artifacts during the observation of maritime targets, due to motion errors. To improve the quality of SAR imaging against motion errors in long synthetic aperture time scenarios, this paper proposes a combined motion compensation (MOCO) method based on subaperture processing. The method first divides the full aperture data into several subapertures. Within each subaperture, the platform is assumed to move at approximately constant velocity. The major imaging step is then combined with two motion compensation operations, which are performed individually within each subaperture. Then, the processed subaperture data are stitched together, and finally, the residual errors are compensated by the third MOCO, resulting in the final image. By simulating maritime observation targets with point targets, simulation results demonstrate that the proposed MOCO algorithm effectively reduce the influence of motion errors, suppress the sidelobe interference to the imaging, and improve the focusing accuracy. Compared with other classical MOCO algorithms, the ISLR_r and ISLR_a metrics show improvements of 0.2662 and 0.8170 dB, respectively. Further verification of the proposed method is conducted by processing the imaging results of measured sea surface data. The proposed algorithm produces clearer wave textures and achieves better imaging performance on targets such as ships in the sea. This result validates the effectiveness and superiority of the proposed method. The proposed method effectively addresses the need for high-precision motion error compensation in high-resolution imaging within long synthetic aperture time system.</description> <pubDate>2025-02-14</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 355: Combined Motion Compensation Method for Long Synthetic Aperture Radar Based on Subaperture Processing Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/355">doi: 10.3390/jmse13020355</a> Authors: Yuan Zhang Limin Huang Zhichao Xu Zihao Wang Biao Chen Long synthetic aperture radar (SAR) offers the advantage of achieving higher resolution by utilizing longer synthetic aperture times, which makes it a promising technology for ocean observation in the future. However, compared to SAR systems with shorter synthetic aperture times, it suffers more severely from issues such as image defocusing, blurring and artifacts during the observation of maritime targets, due to motion errors. To improve the quality of SAR imaging against motion errors in long synthetic aperture time scenarios, this paper proposes a combined motion compensation (MOCO) method based on subaperture processing. The method first divides the full aperture data into several subapertures. Within each subaperture, the platform is assumed to move at approximately constant velocity. The major imaging step is then combined with two motion compensation operations, which are performed individually within each subaperture. Then, the processed subaperture data are stitched together, and finally, the residual errors are compensated by the third MOCO, resulting in the final image. By simulating maritime observation targets with point targets, simulation results demonstrate that the proposed MOCO algorithm effectively reduce the influence of motion errors, suppress the sidelobe interference to the imaging, and improve the focusing accuracy. Compared with other classical MOCO algorithms, the ISLR_r and ISLR_a metrics show improvements of 0.2662 and 0.8170 dB, respectively. Further verification of the proposed method is conducted by processing the imaging results of measured sea surface data. The proposed algorithm produces clearer wave textures and achieves better imaging performance on targets such as ships in the sea. This result validates the effectiveness and superiority of the proposed method. The proposed method effectively addresses the need for high-precision motion error compensation in high-resolution imaging within long synthetic aperture time system. ]]></content:encoded> <dc:title>Combined Motion Compensation Method for Long Synthetic Aperture Radar Based on Subaperture Processing</dc:title> <dc:creator>Yuan Zhang</dc:creator> <dc:creator>Limin Huang</dc:creator> <dc:creator>Zhichao Xu</dc:creator> <dc:creator>Zihao Wang</dc:creator> <dc:creator>Biao Chen</dc:creator> <dc:identifier>doi: 10.3390/jmse13020355</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-14</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-14</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>355</prism:startingPage> <prism:doi>10.3390/jmse13020355</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/355</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/354"> <title>JMSE, Vol. 13, Pages 354: Typhoon Blend Wind Field Optimization Using Wave-Height Hindcasts</title> <link>https://www.mdpi.com/2077-1312/13/2/354</link> <description>Typhoons cause significant losses and pose substantial threats every year, with an increasing trend observed in recent years. This study evaluates significant wave height (SWH) hindcasts for typhoons affecting Taiwan using optimized wind field configurations within the SCHISM-WWM-III coupled model. To enhance typhoon-induced SWH simulations, the blended wind field integrates ERA5 reanalysis wind data with the modified Rankine vortex wind model. Key parameters, including the parametric wind field start time, best track data, and the radius of maximum wind speed, were carefully selected based on analyses of typhoons Meranti and Megi in 2016. Validation metrics such as the skill core, HH indicator, maximum SWH difference, and peak time difference of the SWH indicate that the optimized setup improves the accuracy of simulation. The findings highlight the effectiveness of the adjusted blended wind field, the high-resolution best track data provided by Taiwan, and the maximum wind speed radius in significantly enhancing the accuracy of typhoon wave modeling for the waters surrounding Taiwan.</description> <pubDate>2025-02-14</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 354: Typhoon Blend Wind Field Optimization Using Wave-Height Hindcasts Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/354">doi: 10.3390/jmse13020354</a> Authors: Tzu-Chieh Chen Kai-Cheng Hu Han-Lun Wu Wei-Shiun Lu Wei-Bo Chen Wen-Son Chiang Shih-Chun Hsiao Typhoons cause significant losses and pose substantial threats every year, with an increasing trend observed in recent years. This study evaluates significant wave height (SWH) hindcasts for typhoons affecting Taiwan using optimized wind field configurations within the SCHISM-WWM-III coupled model. To enhance typhoon-induced SWH simulations, the blended wind field integrates ERA5 reanalysis wind data with the modified Rankine vortex wind model. Key parameters, including the parametric wind field start time, best track data, and the radius of maximum wind speed, were carefully selected based on analyses of typhoons Meranti and Megi in 2016. Validation metrics such as the skill core, HH indicator, maximum SWH difference, and peak time difference of the SWH indicate that the optimized setup improves the accuracy of simulation. The findings highlight the effectiveness of the adjusted blended wind field, the high-resolution best track data provided by Taiwan, and the maximum wind speed radius in significantly enhancing the accuracy of typhoon wave modeling for the waters surrounding Taiwan. ]]></content:encoded> <dc:title>Typhoon Blend Wind Field Optimization Using Wave-Height Hindcasts</dc:title> <dc:creator>Tzu-Chieh Chen</dc:creator> <dc:creator>Kai-Cheng Hu</dc:creator> <dc:creator>Han-Lun Wu</dc:creator> <dc:creator>Wei-Shiun Lu</dc:creator> <dc:creator>Wei-Bo Chen</dc:creator> <dc:creator>Wen-Son Chiang</dc:creator> <dc:creator>Shih-Chun Hsiao</dc:creator> <dc:identifier>doi: 10.3390/jmse13020354</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-14</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-14</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>354</prism:startingPage> <prism:doi>10.3390/jmse13020354</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/354</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/353"> <title>JMSE, Vol. 13, Pages 353: Vessel Trajectory Prediction Using Vessel Influence Long Short-Term Memory with Uncertainty Estimation</title> <link>https://www.mdpi.com/2077-1312/13/2/353</link> <description>Vessel trajectory prediction plays a crucial role in ensuring the safety and efficiency of maritime transportation. This study proposes an innovative sequence-to-sequence model, called the Vessel Influence Long Short-Term Memory (VI-LSTM), which introduces a novel Vessel Influence Map (VIM) to quantitatively model the dynamic effects of surrounding vessels. To enhance reliability, VI-LSTM incorporates Gaussian distribution predictions combined with Monte Carlo dropout techniques to estimate prediction uncertainty. Additionally, a temporally weighted hybrid loss function is designed to balance prediction accuracy and uncertainty. Furthermore, this study systematically categorizes and models factors influencing vessel trajectory prediction. Experimental results demonstrate that VI-LSTM achieves a mean distance error of 330.66 m on the standard test set and 480.30 m on an unseen subject test set, outperforming other comparative models, particularly in complex navigation scenarios and high-density maritime environments. These innovations significantly improve the accuracy and generalizability of vessel trajectory predictions, leading to enhanced safety, increased efficiency, and more effective collision avoidance in maritime navigation.</description> <pubDate>2025-02-14</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 353: Vessel Trajectory Prediction Using Vessel Influence Long Short-Term Memory with Uncertainty Estimation Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/353">doi: 10.3390/jmse13020353</a> Authors: Zhiyuan Guo Huimin Qiang Xiaodong Peng Vessel trajectory prediction plays a crucial role in ensuring the safety and efficiency of maritime transportation. This study proposes an innovative sequence-to-sequence model, called the Vessel Influence Long Short-Term Memory (VI-LSTM), which introduces a novel Vessel Influence Map (VIM) to quantitatively model the dynamic effects of surrounding vessels. To enhance reliability, VI-LSTM incorporates Gaussian distribution predictions combined with Monte Carlo dropout techniques to estimate prediction uncertainty. Additionally, a temporally weighted hybrid loss function is designed to balance prediction accuracy and uncertainty. Furthermore, this study systematically categorizes and models factors influencing vessel trajectory prediction. Experimental results demonstrate that VI-LSTM achieves a mean distance error of 330.66 m on the standard test set and 480.30 m on an unseen subject test set, outperforming other comparative models, particularly in complex navigation scenarios and high-density maritime environments. These innovations significantly improve the accuracy and generalizability of vessel trajectory predictions, leading to enhanced safety, increased efficiency, and more effective collision avoidance in maritime navigation. ]]></content:encoded> <dc:title>Vessel Trajectory Prediction Using Vessel Influence Long Short-Term Memory with Uncertainty Estimation</dc:title> <dc:creator>Zhiyuan Guo</dc:creator> <dc:creator>Huimin Qiang</dc:creator> <dc:creator>Xiaodong Peng</dc:creator> <dc:identifier>doi: 10.3390/jmse13020353</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-14</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-14</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>353</prism:startingPage> <prism:doi>10.3390/jmse13020353</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/353</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/352"> <title>JMSE, Vol. 13, Pages 352: The Influence of Voltage Gradient Application History on Electro-Osmotic Reinforcement of Marine Soft Clay</title> <link>https://www.mdpi.com/2077-1312/13/2/352</link> <description>The electric potential gradient is a key factor in electroosmotically reinforcing soft clay. Its application history induces a series of physical and chemical reactions within the soil, influencing the selection of the gradient in the subsequent stage. To gain a deeper understanding of this complex process and its inherent mechanism, electroosmotic reinforcement tests on soft clay were conducted under varying electric voltage gradients. The changes in parameters, including current, drainage volume, shear strength, and water content within the soil, under different application histories of the voltage gradients, were measured. The experimental results demonstrate that the magnitude of the voltage adopted in previous historical stages had a significant impact on the current drainage situation as well as the enhancement of shear strength. During the studied historical period, a relatively high voltage gradient was applied until soil drainage stopped. However, at present, it has become extremely challenging to substantially increase the drainage volume regardless of whether the electrification voltage gradient remains stable, rises, or falls, even when the current does not drop too low. For soil with a high activity index, under an appropriate voltage, the input electrical energy can be more efficiently converted into various physical and chemical processes that enhance soil reinforcement. Regardless of the voltage gradient level adopted, the application of a low voltage gradient in the historical stage exerts a more beneficial influence on the current stage than a high voltage gradient. During the electroosmosis process, efforts should be made to maximize the drainage duration as it facilitates the promotion of the chemical reinforcement effect and reduces energy consumption.</description> <pubDate>2025-02-14</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 352: The Influence of Voltage Gradient Application History on Electro-Osmotic Reinforcement of Marine Soft Clay Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/352">doi: 10.3390/jmse13020352</a> Authors: Zhaohua Sun Yuxing Qing Jianming Zhang Bintang Mas Mediamartha The electric potential gradient is a key factor in electroosmotically reinforcing soft clay. Its application history induces a series of physical and chemical reactions within the soil, influencing the selection of the gradient in the subsequent stage. To gain a deeper understanding of this complex process and its inherent mechanism, electroosmotic reinforcement tests on soft clay were conducted under varying electric voltage gradients. The changes in parameters, including current, drainage volume, shear strength, and water content within the soil, under different application histories of the voltage gradients, were measured. The experimental results demonstrate that the magnitude of the voltage adopted in previous historical stages had a significant impact on the current drainage situation as well as the enhancement of shear strength. During the studied historical period, a relatively high voltage gradient was applied until soil drainage stopped. However, at present, it has become extremely challenging to substantially increase the drainage volume regardless of whether the electrification voltage gradient remains stable, rises, or falls, even when the current does not drop too low. For soil with a high activity index, under an appropriate voltage, the input electrical energy can be more efficiently converted into various physical and chemical processes that enhance soil reinforcement. Regardless of the voltage gradient level adopted, the application of a low voltage gradient in the historical stage exerts a more beneficial influence on the current stage than a high voltage gradient. During the electroosmosis process, efforts should be made to maximize the drainage duration as it facilitates the promotion of the chemical reinforcement effect and reduces energy consumption. ]]></content:encoded> <dc:title>The Influence of Voltage Gradient Application History on Electro-Osmotic Reinforcement of Marine Soft Clay</dc:title> <dc:creator>Zhaohua Sun</dc:creator> <dc:creator>Yuxing Qing</dc:creator> <dc:creator>Jianming Zhang</dc:creator> <dc:creator>Bintang Mas Mediamartha</dc:creator> <dc:identifier>doi: 10.3390/jmse13020352</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-14</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-14</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>352</prism:startingPage> <prism:doi>10.3390/jmse13020352</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/352</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/351"> <title>JMSE, Vol. 13, Pages 351: The Influence of the East Australian Current on the Regional Distribution of Humpback Whales (Megaptera novaeangliae)</title> <link>https://www.mdpi.com/2077-1312/13/2/351</link> <description>Humpback whales (Megaptera novaeangliae) migrate annually along the east coast of Australia, utilizing various habitats, including open embayments such as the Gold Coast bay (GCB) in southeast Queensland, for resting and social behaviors. While their migration is well-documented, the influence of oceanographic factors such as the East Australian Current (EAC)&amp;mdash;a warm ocean current near the GCB&amp;mdash;on humpback whale counts nearshore is not well understood. This study aims to assess the regional distribution of humpback whales in the GCB over consecutive years and investigate how dynamic environmental factors, such as the proximity of the EAC&amp;rsquo;s inner edge to shore and sea surface temperature (SST), affect the distribution and migration patterns of humpback whales. We employed citizen science data to obtain humpback whale sightings and applied generalized additive models (GAM) to evaluate the effects of environmental variables on humpback whale counts. Results suggested that shifts in EAC proximity and SST significantly influence humpback whale presence in the GCB, indicating that oceanographic features may guide migratory pathways and aggregation patterns. These findings improve our understanding of how climatic factors affect coastal humpback whale distributions, providing insights relevant to management and abundance estimates.</description> <pubDate>2025-02-14</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 351: The Influence of the East Australian Current on the Regional Distribution of Humpback Whales (Megaptera novaeangliae) Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/351">doi: 10.3390/jmse13020351</a> Authors: Patrick Woletz Jan-Olaf Meynecke Humpback whales (Megaptera novaeangliae) migrate annually along the east coast of Australia, utilizing various habitats, including open embayments such as the Gold Coast bay (GCB) in southeast Queensland, for resting and social behaviors. While their migration is well-documented, the influence of oceanographic factors such as the East Australian Current (EAC)&amp;mdash;a warm ocean current near the GCB&amp;mdash;on humpback whale counts nearshore is not well understood. This study aims to assess the regional distribution of humpback whales in the GCB over consecutive years and investigate how dynamic environmental factors, such as the proximity of the EAC&amp;rsquo;s inner edge to shore and sea surface temperature (SST), affect the distribution and migration patterns of humpback whales. We employed citizen science data to obtain humpback whale sightings and applied generalized additive models (GAM) to evaluate the effects of environmental variables on humpback whale counts. Results suggested that shifts in EAC proximity and SST significantly influence humpback whale presence in the GCB, indicating that oceanographic features may guide migratory pathways and aggregation patterns. These findings improve our understanding of how climatic factors affect coastal humpback whale distributions, providing insights relevant to management and abundance estimates. ]]></content:encoded> <dc:title>The Influence of the East Australian Current on the Regional Distribution of Humpback Whales (Megaptera novaeangliae)</dc:title> <dc:creator>Patrick Woletz</dc:creator> <dc:creator>Jan-Olaf Meynecke</dc:creator> <dc:identifier>doi: 10.3390/jmse13020351</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-14</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-14</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>351</prism:startingPage> <prism:doi>10.3390/jmse13020351</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/351</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/350"> <title>JMSE, Vol. 13, Pages 350: Reconstruction of Multi-Load Strain Field of Ship Stiffened Plate Based on iFEM and Analysis of Influencing Factors of Reconstruction Accuracy</title> <link>https://www.mdpi.com/2077-1312/13/2/350</link> <description>This study utilizes the inverse finite element method (iFEM) to investigate the strain field reconstruction of ship stiffened plates under multiple loading conditions. The aim is to enhance the monitoring, safety, and reliability of ship structures through multi-condition strain field reconstruction. By applying iFEM, this research addresses the challenge of reconstructing strain fields from discrete strain measurements using a least-squares variational equation derived from elastic mechanics principles. The performance of iFEM was evaluated under five loading conditions: axial compression, non-uniform loading, torsion, combined axial compression with non-uniform loading, and combined axial compression with symmetric uniform loading. To mitigate boundary effects, an extended stiffened plate design was implemented. The results show significant improvements in reconstruction accuracy: under two specific loading conditions, the precision improved by 38.82% and 11.25%, respectively, compared to the original plate. This study underscores the potential of iFEM in improving the monitoring and safety of marine structures. Future work could explore the applicability of iFEM to other marine structures and scenarios, ensuring broader practical applications.</description> <pubDate>2025-02-14</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 350: Reconstruction of Multi-Load Strain Field of Ship Stiffened Plate Based on iFEM and Analysis of Influencing Factors of Reconstruction Accuracy Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/350">doi: 10.3390/jmse13020350</a> Authors: Guocai Chen Xueliang Wang Quanhua Zhu Huawei Yang Zhentao Jiang Hao Xu Mengdan Sun Wei Chen Haozheng Chen Tao Zhang Zheng Zhang This study utilizes the inverse finite element method (iFEM) to investigate the strain field reconstruction of ship stiffened plates under multiple loading conditions. The aim is to enhance the monitoring, safety, and reliability of ship structures through multi-condition strain field reconstruction. By applying iFEM, this research addresses the challenge of reconstructing strain fields from discrete strain measurements using a least-squares variational equation derived from elastic mechanics principles. The performance of iFEM was evaluated under five loading conditions: axial compression, non-uniform loading, torsion, combined axial compression with non-uniform loading, and combined axial compression with symmetric uniform loading. To mitigate boundary effects, an extended stiffened plate design was implemented. The results show significant improvements in reconstruction accuracy: under two specific loading conditions, the precision improved by 38.82% and 11.25%, respectively, compared to the original plate. This study underscores the potential of iFEM in improving the monitoring and safety of marine structures. Future work could explore the applicability of iFEM to other marine structures and scenarios, ensuring broader practical applications. ]]></content:encoded> <dc:title>Reconstruction of Multi-Load Strain Field of Ship Stiffened Plate Based on iFEM and Analysis of Influencing Factors of Reconstruction Accuracy</dc:title> <dc:creator>Guocai Chen</dc:creator> <dc:creator>Xueliang Wang</dc:creator> <dc:creator>Quanhua Zhu</dc:creator> <dc:creator>Huawei Yang</dc:creator> <dc:creator>Zhentao Jiang</dc:creator> <dc:creator>Hao Xu</dc:creator> <dc:creator>Mengdan Sun</dc:creator> <dc:creator>Wei Chen</dc:creator> <dc:creator>Haozheng Chen</dc:creator> <dc:creator>Tao Zhang</dc:creator> <dc:creator>Zheng Zhang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020350</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-14</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-14</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>350</prism:startingPage> <prism:doi>10.3390/jmse13020350</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/350</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/349"> <title>JMSE, Vol. 13, Pages 349: Research on the Response Characteristics of Excavation and Support in Circular Sand Soil Foundation Pit Based on Parameter Verification</title> <link>https://www.mdpi.com/2077-1312/13/2/349</link> <description>This study is aimed at the complex deformation response characteristics of deep soil in the processes of excavation and support of round sand foundation pits. The displacement of the diaphragm wall during the excavation and support of the foundation pit was monitored in a round foundation pit project at the west anchorage of Humen Second Bridge. A full-cycle model of foundation pit excavation was established, and a new method for parameter checking based on the principle of three-factor (c, &amp;phi;, E) multi-level orthogonal experimental design was proposed. Dynamic calibration parameters based on construction monitoring data were obtained. The characteristics of the uplift at the bottom of the foundation pit and the effective plastic strain of the soil before and after the steady-state seepage conditions were applied and analyzed. The most dangerous working conditions (Conditions 5&amp;ndash;6: construction of the fourth layer of lining and excavation of the fifth layer; construction of the fifth layer of lining and excavation at the sixth layer) existed during the excavation and support of the foundation pit. The research method can provide a great practical guiding significance for covering lack of monitoring data at the construction site and early warning analysis on foundation pit excavation.</description> <pubDate>2025-02-14</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 349: Research on the Response Characteristics of Excavation and Support in Circular Sand Soil Foundation Pit Based on Parameter Verification Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/349">doi: 10.3390/jmse13020349</a> Authors: Xuhe Gao Yanqiu Bi Yi Dong Jiading Wang Xiaoling Liu Jiachun Li This study is aimed at the complex deformation response characteristics of deep soil in the processes of excavation and support of round sand foundation pits. The displacement of the diaphragm wall during the excavation and support of the foundation pit was monitored in a round foundation pit project at the west anchorage of Humen Second Bridge. A full-cycle model of foundation pit excavation was established, and a new method for parameter checking based on the principle of three-factor (c, &amp;phi;, E) multi-level orthogonal experimental design was proposed. Dynamic calibration parameters based on construction monitoring data were obtained. The characteristics of the uplift at the bottom of the foundation pit and the effective plastic strain of the soil before and after the steady-state seepage conditions were applied and analyzed. The most dangerous working conditions (Conditions 5&amp;ndash;6: construction of the fourth layer of lining and excavation of the fifth layer; construction of the fifth layer of lining and excavation at the sixth layer) existed during the excavation and support of the foundation pit. The research method can provide a great practical guiding significance for covering lack of monitoring data at the construction site and early warning analysis on foundation pit excavation. ]]></content:encoded> <dc:title>Research on the Response Characteristics of Excavation and Support in Circular Sand Soil Foundation Pit Based on Parameter Verification</dc:title> <dc:creator>Xuhe Gao</dc:creator> <dc:creator>Yanqiu Bi</dc:creator> <dc:creator>Yi Dong</dc:creator> <dc:creator>Jiading Wang</dc:creator> <dc:creator>Xiaoling Liu</dc:creator> <dc:creator>Jiachun Li</dc:creator> <dc:identifier>doi: 10.3390/jmse13020349</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-14</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-14</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>349</prism:startingPage> <prism:doi>10.3390/jmse13020349</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/349</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/348"> <title>JMSE, Vol. 13, Pages 348: Marine Radar Target Ship Echo Generation Algorithm and Simulation Based on Radar Cross-Section</title> <link>https://www.mdpi.com/2077-1312/13/2/348</link> <description>In this study, a simplified radar echo signal model suitable for radar simulators and a Radar Cross-Section (RCS) calculation model based on the Physical Optics (PO) method was developed. A comprehensive radar target ship echo generation algorithm was designed, and the omnidirectional radar RCS values of three typical ships were calculated. The simulation generates radar target ship echo images under varying incident angles (0&amp;ndash;360&amp;deg;), detection distances (0&amp;ndash;24 nautical miles), and three common target material properties. The simulation results, compared with those from existing radar simulators and real radar systems, show that the method proposed in this study, based on RCS values, generates highly realistic radar target ship echoes. It accurately simulates radar echoes under different target ship headings, distances, and material influences, fully meeting the technical requirements of the STCW international convention for radar simulators.</description> <pubDate>2025-02-14</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 348: Marine Radar Target Ship Echo Generation Algorithm and Simulation Based on Radar Cross-Section Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/348">doi: 10.3390/jmse13020348</a> Authors: Chang Li Xiao Yang Hongxiang Ren Shihao Li Xiaoyu Feng In this study, a simplified radar echo signal model suitable for radar simulators and a Radar Cross-Section (RCS) calculation model based on the Physical Optics (PO) method was developed. A comprehensive radar target ship echo generation algorithm was designed, and the omnidirectional radar RCS values of three typical ships were calculated. The simulation generates radar target ship echo images under varying incident angles (0&amp;ndash;360&amp;deg;), detection distances (0&amp;ndash;24 nautical miles), and three common target material properties. The simulation results, compared with those from existing radar simulators and real radar systems, show that the method proposed in this study, based on RCS values, generates highly realistic radar target ship echoes. It accurately simulates radar echoes under different target ship headings, distances, and material influences, fully meeting the technical requirements of the STCW international convention for radar simulators. ]]></content:encoded> <dc:title>Marine Radar Target Ship Echo Generation Algorithm and Simulation Based on Radar Cross-Section</dc:title> <dc:creator>Chang Li</dc:creator> <dc:creator>Xiao Yang</dc:creator> <dc:creator>Hongxiang Ren</dc:creator> <dc:creator>Shihao Li</dc:creator> <dc:creator>Xiaoyu Feng</dc:creator> <dc:identifier>doi: 10.3390/jmse13020348</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-14</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-14</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>348</prism:startingPage> <prism:doi>10.3390/jmse13020348</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/348</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/347"> <title>JMSE, Vol. 13, Pages 347: Spatial State Analysis of Ship During Berthing and Unberthing Process Utilizing Incomplete 3D LiDAR Point Cloud Data</title> <link>https://www.mdpi.com/2077-1312/13/2/347</link> <description>In smart ports, accurately perceiving the motion state of a ship during berthing and unberthing is essential for the safety and efficiency of the ship and port. However, in actual scenarios, the obtained data are not always complete, which impacts the accuracy of the ship&amp;rsquo;s motion state. This paper proposes a spatial visualization method to analyze a ship&amp;rsquo;s motion state in the incomplete data by introducing the GIS spatial theory. First, for the complete part under incomplete data, this method proposes a new technique named LGFCT to extract the key points of this part. Then, for the missing part under the incomplete data, this method applies the key point prediction technique based on the line features to extract the key points of this part. Note that the key points will be used to calculate the key parameters. Finally, spatial visualization and spatial-temporal tracking techniques are employed to spatially analyze the ship&amp;rsquo;s motion state. In summary, the proposed method not only spatially identifies a ship&amp;rsquo;s motion state for the incomplete data but also provides an intuitive visualization of a ship&amp;rsquo;s spatial motion state. The accuracy and effectiveness of the proposed method are verified through experimental data collected from a ship in Dalian Port, China.</description> <pubDate>2025-02-14</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 347: Spatial State Analysis of Ship During Berthing and Unberthing Process Utilizing Incomplete 3D LiDAR Point Cloud Data Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/347">doi: 10.3390/jmse13020347</a> Authors: Ying Li Tian-Qi Wang In smart ports, accurately perceiving the motion state of a ship during berthing and unberthing is essential for the safety and efficiency of the ship and port. However, in actual scenarios, the obtained data are not always complete, which impacts the accuracy of the ship&amp;rsquo;s motion state. This paper proposes a spatial visualization method to analyze a ship&amp;rsquo;s motion state in the incomplete data by introducing the GIS spatial theory. First, for the complete part under incomplete data, this method proposes a new technique named LGFCT to extract the key points of this part. Then, for the missing part under the incomplete data, this method applies the key point prediction technique based on the line features to extract the key points of this part. Note that the key points will be used to calculate the key parameters. Finally, spatial visualization and spatial-temporal tracking techniques are employed to spatially analyze the ship&amp;rsquo;s motion state. In summary, the proposed method not only spatially identifies a ship&amp;rsquo;s motion state for the incomplete data but also provides an intuitive visualization of a ship&amp;rsquo;s spatial motion state. The accuracy and effectiveness of the proposed method are verified through experimental data collected from a ship in Dalian Port, China. ]]></content:encoded> <dc:title>Spatial State Analysis of Ship During Berthing and Unberthing Process Utilizing Incomplete 3D LiDAR Point Cloud Data</dc:title> <dc:creator>Ying Li</dc:creator> <dc:creator>Tian-Qi Wang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020347</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-14</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-14</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>347</prism:startingPage> <prism:doi>10.3390/jmse13020347</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/347</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/346"> <title>JMSE, Vol. 13, Pages 346: Vertically Moving Target Localization Based on Interference Feature Matching Using a Single Hydrophone</title> <link>https://www.mdpi.com/2077-1312/13/2/346</link> <description>To address the performance degradation of traditional underwater target localization algorithms in high-speed motion scenarios, this paper proposes a vertically moving localization method based on interference feature matching using a single hydrophone. Due to the overlapping of interference fringes in the time&amp;ndash;frequency domain, the method first employs a two-dimensional homomorphic filter to separate different types of interference fringes while removing line-spectrum interference. Then, a theoretical interference period database is constructed, and feature matching is performed on the interference fringes to achieve localization of the vertically moving target. Simulation results show that, under conditions of strong broadband noise and line-spectrum interference, the proposed method effectively separates and restores the interference fringes of high-speed vertically moving targets and successfully locates the moving target under large Doppler conditions. Further validation using field data from Qiandao Lake confirms that the actual measurements align with theoretical analysis, validating the effectiveness of the proposed method.</description> <pubDate>2025-02-13</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 346: Vertically Moving Target Localization Based on Interference Feature Matching Using a Single Hydrophone Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/346">doi: 10.3390/jmse13020346</a> Authors: Chunpeng Zhao Guolong Liang Longhao Qiu Jinjin Wang Wenfeng Dong To address the performance degradation of traditional underwater target localization algorithms in high-speed motion scenarios, this paper proposes a vertically moving localization method based on interference feature matching using a single hydrophone. Due to the overlapping of interference fringes in the time&amp;ndash;frequency domain, the method first employs a two-dimensional homomorphic filter to separate different types of interference fringes while removing line-spectrum interference. Then, a theoretical interference period database is constructed, and feature matching is performed on the interference fringes to achieve localization of the vertically moving target. Simulation results show that, under conditions of strong broadband noise and line-spectrum interference, the proposed method effectively separates and restores the interference fringes of high-speed vertically moving targets and successfully locates the moving target under large Doppler conditions. Further validation using field data from Qiandao Lake confirms that the actual measurements align with theoretical analysis, validating the effectiveness of the proposed method. ]]></content:encoded> <dc:title>Vertically Moving Target Localization Based on Interference Feature Matching Using a Single Hydrophone</dc:title> <dc:creator>Chunpeng Zhao</dc:creator> <dc:creator>Guolong Liang</dc:creator> <dc:creator>Longhao Qiu</dc:creator> <dc:creator>Jinjin Wang</dc:creator> <dc:creator>Wenfeng Dong</dc:creator> <dc:identifier>doi: 10.3390/jmse13020346</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-13</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-13</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>346</prism:startingPage> <prism:doi>10.3390/jmse13020346</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/346</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/345"> <title>JMSE, Vol. 13, Pages 345: A Time-Delay Overlapping Modulation-Based Maritime High-Speed and High-Spectral-Efficiency Communication Technology</title> <link>https://www.mdpi.com/2077-1312/13/2/345</link> <description>To simultaneously address dual demands on the spectral efficiency and the data transmission rate of maritime communications, in this paper, a novel maritime communication technology based on time-delay overlapping modulation (TDOM) is proposed. In TDOM, multiple carriers are delayed in turn and directly overlapped in the time domain to form the communication symbol. In this way, the strict orthogonality between carriers can be broken through, indicating that the frequency interval between carriers can be much narrower than ever. In other words, TDOM can achieve non-orthogonal communication and realize both higher spectral efficiency and a higher maritime communication rate. The system architecture is designed, and its performance is analyzed and compared with that of other typical maritime communication technologies such as the very-high-frequency data exchange system (VDES). It is shown that TDOM can reach up to 20 times the peak communication rate and the spectral efficiency of VDES. As a digital modulation technology implemented in the physical layer, the proposed TDOM can be extended to other communication systems such as satellite communications or 4G/5G based off-shore communications.</description> <pubDate>2025-02-13</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 345: A Time-Delay Overlapping Modulation-Based Maritime High-Speed and High-Spectral-Efficiency Communication Technology Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/345">doi: 10.3390/jmse13020345</a> Authors: Xinyu Dou Teng Ma Dequn Liang To simultaneously address dual demands on the spectral efficiency and the data transmission rate of maritime communications, in this paper, a novel maritime communication technology based on time-delay overlapping modulation (TDOM) is proposed. In TDOM, multiple carriers are delayed in turn and directly overlapped in the time domain to form the communication symbol. In this way, the strict orthogonality between carriers can be broken through, indicating that the frequency interval between carriers can be much narrower than ever. In other words, TDOM can achieve non-orthogonal communication and realize both higher spectral efficiency and a higher maritime communication rate. The system architecture is designed, and its performance is analyzed and compared with that of other typical maritime communication technologies such as the very-high-frequency data exchange system (VDES). It is shown that TDOM can reach up to 20 times the peak communication rate and the spectral efficiency of VDES. As a digital modulation technology implemented in the physical layer, the proposed TDOM can be extended to other communication systems such as satellite communications or 4G/5G based off-shore communications. ]]></content:encoded> <dc:title>A Time-Delay Overlapping Modulation-Based Maritime High-Speed and High-Spectral-Efficiency Communication Technology</dc:title> <dc:creator>Xinyu Dou</dc:creator> <dc:creator>Teng Ma</dc:creator> <dc:creator>Dequn Liang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020345</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-13</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-13</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>345</prism:startingPage> <prism:doi>10.3390/jmse13020345</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/345</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/344"> <title>JMSE, Vol. 13, Pages 344: Evaluation of Deep Learning Models for Polymetallic Nodule Detection and Segmentation in Seafloor Imagery</title> <link>https://www.mdpi.com/2077-1312/13/2/344</link> <description>Climate change has led to the need to transition to clean technologies, which depend on an number of critical metals. These metals, such as nickel, lithium, and manganese, are essential for developing batteries. However, the scarcity of these elements and the risks of disruptions to their supply chain have increased interest in exploiting resources on the deep seabed, particularly polymetallic nodules. As the identification of these nodules must be efficient to minimize disturbance to the marine ecosystem, deep learning techniques have emerged as a potential solution. Traditional deep learning methods are based on the use of convolutional layers to extract features, while recent architectures, such as transformer-based architectures, use self-attention mechanisms to obtain global context. This paper evaluates the performance of representative models from both categories across three tasks: detection, object segmentation, and semantic segmentation. The initial results suggest that transformer-based methods perform better in most evaluation metrics, but at the cost of higher computational resources. Furthermore, recent versions of You Only Look Once (YOLO) have obtained competitive results in terms of mean average precision.</description> <pubDate>2025-02-13</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 344: Evaluation of Deep Learning Models for Polymetallic Nodule Detection and Segmentation in Seafloor Imagery Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/344">doi: 10.3390/jmse13020344</a> Authors: Gabriel Loureiro Andr茅 Dias Jos茅 Almeida Alfredo Martins Eduardo Silva Climate change has led to the need to transition to clean technologies, which depend on an number of critical metals. These metals, such as nickel, lithium, and manganese, are essential for developing batteries. However, the scarcity of these elements and the risks of disruptions to their supply chain have increased interest in exploiting resources on the deep seabed, particularly polymetallic nodules. As the identification of these nodules must be efficient to minimize disturbance to the marine ecosystem, deep learning techniques have emerged as a potential solution. Traditional deep learning methods are based on the use of convolutional layers to extract features, while recent architectures, such as transformer-based architectures, use self-attention mechanisms to obtain global context. This paper evaluates the performance of representative models from both categories across three tasks: detection, object segmentation, and semantic segmentation. The initial results suggest that transformer-based methods perform better in most evaluation metrics, but at the cost of higher computational resources. Furthermore, recent versions of You Only Look Once (YOLO) have obtained competitive results in terms of mean average precision. ]]></content:encoded> <dc:title>Evaluation of Deep Learning Models for Polymetallic Nodule Detection and Segmentation in Seafloor Imagery</dc:title> <dc:creator>Gabriel Loureiro</dc:creator> <dc:creator>Andr茅 Dias</dc:creator> <dc:creator>Jos茅 Almeida</dc:creator> <dc:creator>Alfredo Martins</dc:creator> <dc:creator>Eduardo Silva</dc:creator> <dc:identifier>doi: 10.3390/jmse13020344</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-13</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-13</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>344</prism:startingPage> <prism:doi>10.3390/jmse13020344</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/344</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/343"> <title>JMSE, Vol. 13, Pages 343: Nitrate &delta;15N and &delta;18O Values Reveal Mariculture Impacts on Nitrogen Cycling in Sansha Bay, SE China</title> <link>https://www.mdpi.com/2077-1312/13/2/343</link> <description>Global fisheries&amp;rsquo; production has intensified rapidly over recent decades, making significant contributions to food security and economic development. However, this growth has exerted pressure on marine ecosystems and altered coastal nitrogen cycling. This study focused on Sansha Bay, an important aquaculture harbor in SE China, with measurements of environmental parameters and nitrate N&amp;ndash;O isotopic compositions, to explore the impact of distinct mariculture types on nitrogen cycling in a coastal farming bay. The mean nitrate concentration was 120.7 &amp;plusmn; 24.2 &amp;mu;mol dm&amp;minus;3, with a mean N/P ratio of 69.6 &amp;plusmn; 19.6, indicating that the water column is in a state of eutrophication. Different aquaculture practices influence the nutrient status of water, with mixed farming (shellfish, seaweed, and fish) increasing nitrate concentrations and reducing N/P ratios, while seaweed farming reduces nitrate concentrations and increases N/P ratios. In spring, the average &amp;delta;15N and &amp;delta;18O values of nitrate in the water column were 8.4&amp;permil; and 8.7&amp;permil;, respectively, compared with values of 9.8&amp;permil; and 4&amp;permil; recorded previously in winter. Such variation may be attributed to the greater influence of seaweed farming in spring when nitrate cycling is driven mainly by assimilation. In terms of aquaculture type, nitrate assimilation was stronger in seaweed farming zones, and nitrification was more pronounced in mixed farming zones. Overall, the results demonstrate that different mariculture types in Sansha Bay influence nitrogen cycling in the water body, with seaweed-based aquaculture systems contributing to the sustainable development of marine aquaculture by effectively mitigating eutrophication.</description> <pubDate>2025-02-13</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 343: Nitrate &delta;15N and &delta;18O Values Reveal Mariculture Impacts on Nitrogen Cycling in Sansha Bay, SE China Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/343">doi: 10.3390/jmse13020343</a> Authors: Jianpeng Li Xuan Lu Qingmei Zhu Yanpei Zhuang Wei Yang Di Qi Global fisheries&amp;rsquo; production has intensified rapidly over recent decades, making significant contributions to food security and economic development. However, this growth has exerted pressure on marine ecosystems and altered coastal nitrogen cycling. This study focused on Sansha Bay, an important aquaculture harbor in SE China, with measurements of environmental parameters and nitrate N&amp;ndash;O isotopic compositions, to explore the impact of distinct mariculture types on nitrogen cycling in a coastal farming bay. The mean nitrate concentration was 120.7 &amp;plusmn; 24.2 &amp;mu;mol dm&amp;minus;3, with a mean N/P ratio of 69.6 &amp;plusmn; 19.6, indicating that the water column is in a state of eutrophication. Different aquaculture practices influence the nutrient status of water, with mixed farming (shellfish, seaweed, and fish) increasing nitrate concentrations and reducing N/P ratios, while seaweed farming reduces nitrate concentrations and increases N/P ratios. In spring, the average &amp;delta;15N and &amp;delta;18O values of nitrate in the water column were 8.4&amp;permil; and 8.7&amp;permil;, respectively, compared with values of 9.8&amp;permil; and 4&amp;permil; recorded previously in winter. Such variation may be attributed to the greater influence of seaweed farming in spring when nitrate cycling is driven mainly by assimilation. In terms of aquaculture type, nitrate assimilation was stronger in seaweed farming zones, and nitrification was more pronounced in mixed farming zones. Overall, the results demonstrate that different mariculture types in Sansha Bay influence nitrogen cycling in the water body, with seaweed-based aquaculture systems contributing to the sustainable development of marine aquaculture by effectively mitigating eutrophication. ]]></content:encoded> <dc:title>Nitrate &amp;delta;15N and &amp;delta;18O Values Reveal Mariculture Impacts on Nitrogen Cycling in Sansha Bay, SE China</dc:title> <dc:creator>Jianpeng Li</dc:creator> <dc:creator>Xuan Lu</dc:creator> <dc:creator>Qingmei Zhu</dc:creator> <dc:creator>Yanpei Zhuang</dc:creator> <dc:creator>Wei Yang</dc:creator> <dc:creator>Di Qi</dc:creator> <dc:identifier>doi: 10.3390/jmse13020343</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-13</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-13</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>343</prism:startingPage> <prism:doi>10.3390/jmse13020343</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/343</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/342"> <title>JMSE, Vol. 13, Pages 342: Laboratory Investigation of the Uplift Resistance of a New Winged H-Pile Anchor Developed for Offshore Marine Aquaculture</title> <link>https://www.mdpi.com/2077-1312/13/2/342</link> <description>To enhance the stability and safety of marine aquaculture facilities by addressing the limited uplift resistance capacity and susceptibility to deflection of conventional straight-shafted piles, this study introduces an improved H-pile anchor and conducted laboratory experiments. The new anchor incorporates resized H-piles with wing plates added to both sides, optimized for area and placement, as well as an adjusted loading angle. The findings demonstrate a positive correlation between the uplift resistance capacity of the H-pile anchor and its length and width, indicating that while increased pile length significantly enhances resistance, widening has a minimal impact. Additionally, enlarging the wing plate area improves the resistance; however, efficiency (&amp;delta;) decreases with the increase in the area, suggesting the existence of an optimal size. The optimal wing plate dimensions (L = 80 mm, W = 25 mm) improve uplift resistance by at least 10.6% compared to non-wing pile anchors. Furthermore, positioning the wing plates at the base of the pile anchor rather than the top enhances resistance by approximately 13.8%. Setting the anchor layout angle to 45&amp;deg; reduced the displacement under inclined loads. This research provides essential theoretical support and practical guidance for strengthening the safety and stability of marine aquaculture facilities.</description> <pubDate>2025-02-13</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 342: Laboratory Investigation of the Uplift Resistance of a New Winged H-Pile Anchor Developed for Offshore Marine Aquaculture Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/342">doi: 10.3390/jmse13020342</a> Authors: Xu Yang Lianghao Tang Lili Mei Tianyuan Zhang Shuai Niu Zhefei Sun Zhenliang Wang Dejun Feng Fukun Gui To enhance the stability and safety of marine aquaculture facilities by addressing the limited uplift resistance capacity and susceptibility to deflection of conventional straight-shafted piles, this study introduces an improved H-pile anchor and conducted laboratory experiments. The new anchor incorporates resized H-piles with wing plates added to both sides, optimized for area and placement, as well as an adjusted loading angle. The findings demonstrate a positive correlation between the uplift resistance capacity of the H-pile anchor and its length and width, indicating that while increased pile length significantly enhances resistance, widening has a minimal impact. Additionally, enlarging the wing plate area improves the resistance; however, efficiency (&amp;delta;) decreases with the increase in the area, suggesting the existence of an optimal size. The optimal wing plate dimensions (L = 80 mm, W = 25 mm) improve uplift resistance by at least 10.6% compared to non-wing pile anchors. Furthermore, positioning the wing plates at the base of the pile anchor rather than the top enhances resistance by approximately 13.8%. Setting the anchor layout angle to 45&amp;deg; reduced the displacement under inclined loads. This research provides essential theoretical support and practical guidance for strengthening the safety and stability of marine aquaculture facilities. ]]></content:encoded> <dc:title>Laboratory Investigation of the Uplift Resistance of a New Winged H-Pile Anchor Developed for Offshore Marine Aquaculture</dc:title> <dc:creator>Xu Yang</dc:creator> <dc:creator>Lianghao Tang</dc:creator> <dc:creator>Lili Mei</dc:creator> <dc:creator>Tianyuan Zhang</dc:creator> <dc:creator>Shuai Niu</dc:creator> <dc:creator>Zhefei Sun</dc:creator> <dc:creator>Zhenliang Wang</dc:creator> <dc:creator>Dejun Feng</dc:creator> <dc:creator>Fukun Gui</dc:creator> <dc:identifier>doi: 10.3390/jmse13020342</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-13</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-13</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>342</prism:startingPage> <prism:doi>10.3390/jmse13020342</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/342</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/341"> <title>JMSE, Vol. 13, Pages 341: Spatial Variability Analysis of Renewal Time in Harbour Environments Using a Lagrangian Model</title> <link>https://www.mdpi.com/2077-1312/13/2/341</link> <description>The water quality in port domains is highly dependent on the capacity for renewal and mixing with external water. This study uses Lagrangian modelling to investigate renewal time in Barcelona, Tarragona, and Gij&amp;oacute;n harbours (Spain), which represent semi-enclosed micro-tidal and meso-tidal environments. For this purpose, different particle-tracking simulations have been carried out in each of the ports to study the trends of circulation and water renewal trends both on the surface layer and at the bottom. The results indicate that in microtidal Mediterranean ports, the renewal time is longer at the bottom (32 days in Barcelona and 61 days in Tarragona). Conversely, in the mesotidal port of Gij&amp;oacute;n, located on the Cantabrian coast, the opposite pattern is observed, with higher renewal times at the surface (14 days). While the results from Lagrangian modelling exhibit magnitudes comparable to in situ measurements from previous studies, it remains essential to evaluate the specific characteristics of each method and compare these findings with other similar works.</description> <pubDate>2025-02-13</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 341: Spatial Variability Analysis of Renewal Time in Harbour Environments Using a Lagrangian Model Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/341">doi: 10.3390/jmse13020341</a> Authors: Yaiza Samper Ivan Hern谩ndez Leidy M. Castro-Rosero Maria Liste Manuel Espino Jos茅 M. Alsina The water quality in port domains is highly dependent on the capacity for renewal and mixing with external water. This study uses Lagrangian modelling to investigate renewal time in Barcelona, Tarragona, and Gij&amp;oacute;n harbours (Spain), which represent semi-enclosed micro-tidal and meso-tidal environments. For this purpose, different particle-tracking simulations have been carried out in each of the ports to study the trends of circulation and water renewal trends both on the surface layer and at the bottom. The results indicate that in microtidal Mediterranean ports, the renewal time is longer at the bottom (32 days in Barcelona and 61 days in Tarragona). Conversely, in the mesotidal port of Gij&amp;oacute;n, located on the Cantabrian coast, the opposite pattern is observed, with higher renewal times at the surface (14 days). While the results from Lagrangian modelling exhibit magnitudes comparable to in situ measurements from previous studies, it remains essential to evaluate the specific characteristics of each method and compare these findings with other similar works. ]]></content:encoded> <dc:title>Spatial Variability Analysis of Renewal Time in Harbour Environments Using a Lagrangian Model</dc:title> <dc:creator>Yaiza Samper</dc:creator> <dc:creator>Ivan Hern谩ndez</dc:creator> <dc:creator>Leidy M. Castro-Rosero</dc:creator> <dc:creator>Maria Liste</dc:creator> <dc:creator>Manuel Espino</dc:creator> <dc:creator>Jos茅 M. Alsina</dc:creator> <dc:identifier>doi: 10.3390/jmse13020341</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-13</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-13</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>341</prism:startingPage> <prism:doi>10.3390/jmse13020341</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/341</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/340"> <title>JMSE, Vol. 13, Pages 340: A Monocular Vision-Based Safety Monitoring Framework for Offshore Infrastructures Utilizing Grounded SAM</title> <link>https://www.mdpi.com/2077-1312/13/2/340</link> <description>As maritime transportation and human activities at sea continue to grow, ensuring the safety of offshore infrastructure has become an increasingly pressing research focus. However, traditional high-precision sensor systems often involve prohibitive costs, and the Automatic Identification System (AIS) faces signal loss or data manipulation problems, highlighting the need for a complementary, affordable, and reliable supplemental solution. This study introduces a monocular vision-based safety monitoring framework for offshore infrastructures. By combining advanced computer vision techniques such as Grounded SAM and horizon-based self-calibration, the proposed framework achieves accurate vessel detection, instance segmentation, and distance estimation. The model integrates open-vocabulary object detection and zero-shot segmentation, achieving high performance without additional training. To demonstrate the feasibility of the framework in practical applications, we conduct several experiments on public datasets and couple the proposed algorithms with the Leaflet.js and WebRTC libraries to develop a web-based prototype for real-time safety monitoring, providing visualized information and alerts for offshore infrastructure operators in our case study. The experimental results and case study suggest that the framework has notable advantages, including low cost, convenient deployment with minimal maintenance, high detection accuracy, and strong adaptability to diverse application conditions, which brings a supplemental solution to research on offshore infrastructure safety.</description> <pubDate>2025-02-13</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 340: A Monocular Vision-Based Safety Monitoring Framework for Offshore Infrastructures Utilizing Grounded SAM Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/340">doi: 10.3390/jmse13020340</a> Authors: Sijie Xia Rufu Qin Yang Lu Lianjiang Ma Zhenghu Liu As maritime transportation and human activities at sea continue to grow, ensuring the safety of offshore infrastructure has become an increasingly pressing research focus. However, traditional high-precision sensor systems often involve prohibitive costs, and the Automatic Identification System (AIS) faces signal loss or data manipulation problems, highlighting the need for a complementary, affordable, and reliable supplemental solution. This study introduces a monocular vision-based safety monitoring framework for offshore infrastructures. By combining advanced computer vision techniques such as Grounded SAM and horizon-based self-calibration, the proposed framework achieves accurate vessel detection, instance segmentation, and distance estimation. The model integrates open-vocabulary object detection and zero-shot segmentation, achieving high performance without additional training. To demonstrate the feasibility of the framework in practical applications, we conduct several experiments on public datasets and couple the proposed algorithms with the Leaflet.js and WebRTC libraries to develop a web-based prototype for real-time safety monitoring, providing visualized information and alerts for offshore infrastructure operators in our case study. The experimental results and case study suggest that the framework has notable advantages, including low cost, convenient deployment with minimal maintenance, high detection accuracy, and strong adaptability to diverse application conditions, which brings a supplemental solution to research on offshore infrastructure safety. ]]></content:encoded> <dc:title>A Monocular Vision-Based Safety Monitoring Framework for Offshore Infrastructures Utilizing Grounded SAM</dc:title> <dc:creator>Sijie Xia</dc:creator> <dc:creator>Rufu Qin</dc:creator> <dc:creator>Yang Lu</dc:creator> <dc:creator>Lianjiang Ma</dc:creator> <dc:creator>Zhenghu Liu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020340</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-13</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-13</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>340</prism:startingPage> <prism:doi>10.3390/jmse13020340</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/340</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/339"> <title>JMSE, Vol. 13, Pages 339: Provenance Evolution of the Paleogene Enping Formation in the Northern Pearl River Mouth Basin and Its Influence on the Sedimentary Infilling of Offshore Petroliferous Sags</title> <link>https://www.mdpi.com/2077-1312/13/2/339</link> <description>The Pearl River Mouth Basin (PRMB) had two potential provenances (intrabasinal and extrabasinal) during the Paleogene Enping Formation period. However, the understanding of their differences in source supply and evolution over time and space is limited due to the regional restriction in borehole coverage. This study aims to address the knowledge gap by utilizing detrital zircon U-Pb dating data, seismic data, and borehole data. Specifically, this study focuses on examining the characteristics of provenance evolution and sedimentary infilling within the Enping Formation in various sags of the northern PRMB. The results indicate temporal and spatial variability in provenance from the lower Ep4 and Ep3 to the upper Ep2 and Ep1 Members. The influence of extrabasinal provenance from the South China Block (SCB) was prominent in the northern region of the Zhu I Depression during the deposition of Ep4 and Ep3 Members, while intrabasinal provenance from local uplifts remained a significant source for most sags. During this period, sediment transportation occurred over short distances, leading to the widespread development of smaller fan deltas and braided river deltas. In contrast, extrabasinal provenance became dominant during the deposition of Ep2 and Ep1 Members throughout the entire Zhu I Depression. This shift promoted the development of large-scale, shallow, braided river deltas with sediment transported over long distances. The analysis reveals a close correspondence between the shifting provenance and the evolution of sedimentary infilling patterns in the PRMB. As a result, the sags transitioned from being under-filled or balanced-filled to being balanced-filled or over-filled. This study holds immense significance for oil and gas exploration as well as the prediction of favorable sedimentary sand bodies in offshore petroliferous basins.</description> <pubDate>2025-02-13</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 339: Provenance Evolution of the Paleogene Enping Formation in the Northern Pearl River Mouth Basin and Its Influence on the Sedimentary Infilling of Offshore Petroliferous Sags Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/339">doi: 10.3390/jmse13020339</a> Authors: Shengqian Liu Youbin He Zhongxiang Zhao Ying Chen The Pearl River Mouth Basin (PRMB) had two potential provenances (intrabasinal and extrabasinal) during the Paleogene Enping Formation period. However, the understanding of their differences in source supply and evolution over time and space is limited due to the regional restriction in borehole coverage. This study aims to address the knowledge gap by utilizing detrital zircon U-Pb dating data, seismic data, and borehole data. Specifically, this study focuses on examining the characteristics of provenance evolution and sedimentary infilling within the Enping Formation in various sags of the northern PRMB. The results indicate temporal and spatial variability in provenance from the lower Ep4 and Ep3 to the upper Ep2 and Ep1 Members. The influence of extrabasinal provenance from the South China Block (SCB) was prominent in the northern region of the Zhu I Depression during the deposition of Ep4 and Ep3 Members, while intrabasinal provenance from local uplifts remained a significant source for most sags. During this period, sediment transportation occurred over short distances, leading to the widespread development of smaller fan deltas and braided river deltas. In contrast, extrabasinal provenance became dominant during the deposition of Ep2 and Ep1 Members throughout the entire Zhu I Depression. This shift promoted the development of large-scale, shallow, braided river deltas with sediment transported over long distances. The analysis reveals a close correspondence between the shifting provenance and the evolution of sedimentary infilling patterns in the PRMB. As a result, the sags transitioned from being under-filled or balanced-filled to being balanced-filled or over-filled. This study holds immense significance for oil and gas exploration as well as the prediction of favorable sedimentary sand bodies in offshore petroliferous basins. ]]></content:encoded> <dc:title>Provenance Evolution of the Paleogene Enping Formation in the Northern Pearl River Mouth Basin and Its Influence on the Sedimentary Infilling of Offshore Petroliferous Sags</dc:title> <dc:creator>Shengqian Liu</dc:creator> <dc:creator>Youbin He</dc:creator> <dc:creator>Zhongxiang Zhao</dc:creator> <dc:creator>Ying Chen</dc:creator> <dc:identifier>doi: 10.3390/jmse13020339</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-13</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-13</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>339</prism:startingPage> <prism:doi>10.3390/jmse13020339</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/339</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/338"> <title>JMSE, Vol. 13, Pages 338: Combinatorial-Testing-Based Multi-Ship Encounter Scenario Generation for Collision Avoidance Algorithm Evaluation</title> <link>https://www.mdpi.com/2077-1312/13/2/338</link> <description>Collision avoidance algorithms play a crucial role in ensuring the safety and effectiveness of autonomous ships, which require comprehensive testing in realistic multi-ship encounter scenarios. However, existing scenario generation methods often inadequately represent the spatiotemporal complexity and dynamic risk interactions of real-world encounters, leading to biased evaluations. To bridge this gap, this paper proposes a combinatorial-testing-based scenario generation framework integrated with spatiotemporal complexity optimisation. First, a full-process scenario representation model is developed by abstracting real-world navigation features into a discretised parameter space. Subsequently, a combinatorial-testing-based scenario generation method is adopted to cover the parameter space, generating a high-coverage scenario set. Finally, spatiotemporal complexity is introduced to filter out oversimplified scenarios and extremely dangerous scenarios. Experiments demonstrated that 13.7% of generated scenarios were eliminated as unrealistic or trivial, while high-risk encounter scenarios and multi-ship interaction scenarios were amplified by 7.96 times and 5.84 times, respectively. Compared to conventional methods, the optimised scenario set exhibited superior alignment with real-world complexity, including dynamic risk escalation and multi-ship coordination challenges. The proposed framework not only advances scenario generation methodology through its integration of combinatorial testing and complexity-driven optimisation, but also provides a practical tool for rigorously validating autonomous ship safety systems.</description> <pubDate>2025-02-12</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 338: Combinatorial-Testing-Based Multi-Ship Encounter Scenario Generation for Collision Avoidance Algorithm Evaluation Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/338">doi: 10.3390/jmse13020338</a> Authors: Lijia Chen Kai Wang Kezhong Liu Yang Zhou Guozhu Hao Yang Wang Shengwei Li Collision avoidance algorithms play a crucial role in ensuring the safety and effectiveness of autonomous ships, which require comprehensive testing in realistic multi-ship encounter scenarios. However, existing scenario generation methods often inadequately represent the spatiotemporal complexity and dynamic risk interactions of real-world encounters, leading to biased evaluations. To bridge this gap, this paper proposes a combinatorial-testing-based scenario generation framework integrated with spatiotemporal complexity optimisation. First, a full-process scenario representation model is developed by abstracting real-world navigation features into a discretised parameter space. Subsequently, a combinatorial-testing-based scenario generation method is adopted to cover the parameter space, generating a high-coverage scenario set. Finally, spatiotemporal complexity is introduced to filter out oversimplified scenarios and extremely dangerous scenarios. Experiments demonstrated that 13.7% of generated scenarios were eliminated as unrealistic or trivial, while high-risk encounter scenarios and multi-ship interaction scenarios were amplified by 7.96 times and 5.84 times, respectively. Compared to conventional methods, the optimised scenario set exhibited superior alignment with real-world complexity, including dynamic risk escalation and multi-ship coordination challenges. The proposed framework not only advances scenario generation methodology through its integration of combinatorial testing and complexity-driven optimisation, but also provides a practical tool for rigorously validating autonomous ship safety systems. ]]></content:encoded> <dc:title>Combinatorial-Testing-Based Multi-Ship Encounter Scenario Generation for Collision Avoidance Algorithm Evaluation</dc:title> <dc:creator>Lijia Chen</dc:creator> <dc:creator>Kai Wang</dc:creator> <dc:creator>Kezhong Liu</dc:creator> <dc:creator>Yang Zhou</dc:creator> <dc:creator>Guozhu Hao</dc:creator> <dc:creator>Yang Wang</dc:creator> <dc:creator>Shengwei Li</dc:creator> <dc:identifier>doi: 10.3390/jmse13020338</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-12</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-12</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>338</prism:startingPage> <prism:doi>10.3390/jmse13020338</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/338</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/337"> <title>JMSE, Vol. 13, Pages 337: Study on Influence of Configuration of Bulges on Stall Characteristics of Two-Element Wingsails for Ships</title> <link>https://www.mdpi.com/2077-1312/13/2/337</link> <description>The tubercles on the flipper of humpback whales are beneficial for improving their locomotion performance. Based on biomimetic design, the bulge model was developed to mimic this function through cubic B-spline curve fitting, aiming to improve the stall performance of the two-element wingsail. The numerical calculation method was validated against experiments to ensure the reliability of the numerical results. Five models of the bulges of the main wing were developed, and the influence of different bulges on the stall performance of the two-element wingsail under logarithmic gradient wind conditions was examined. By analyzing its lift and drag characteristics, pressure load distribution, and flow field near the stall angle, the mechanism by which the bulges improved the stall characteristics of the two-element wingsail was revealed. The result indicated that the two-element wingsail in the Case 5 scheme has a maximum lift coefficient of 1.25, and that the lift reduction in the early stage of stall is only 8.8%, which is 43.6% less than the original wingsail lift reduction. As the bulge size increases the strength of the forward vortex created by the middle larger bulge increases, resulting in the absence of a symmetrical vortex structure on the suction surface of the wingsail, causing high fluid momentum band deflection. The energy of the boundary layer is supplemented by vorticity transport, promoting the formation of attached flow on the side of the smaller bulge and improving the lift coefficient.</description> <pubDate>2025-02-12</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 337: Study on Influence of Configuration of Bulges on Stall Characteristics of Two-Element Wingsails for Ships Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/337">doi: 10.3390/jmse13020337</a> Authors: Chen Li Binxin Wu Huabing Wen Junfu Yuan The tubercles on the flipper of humpback whales are beneficial for improving their locomotion performance. Based on biomimetic design, the bulge model was developed to mimic this function through cubic B-spline curve fitting, aiming to improve the stall performance of the two-element wingsail. The numerical calculation method was validated against experiments to ensure the reliability of the numerical results. Five models of the bulges of the main wing were developed, and the influence of different bulges on the stall performance of the two-element wingsail under logarithmic gradient wind conditions was examined. By analyzing its lift and drag characteristics, pressure load distribution, and flow field near the stall angle, the mechanism by which the bulges improved the stall characteristics of the two-element wingsail was revealed. The result indicated that the two-element wingsail in the Case 5 scheme has a maximum lift coefficient of 1.25, and that the lift reduction in the early stage of stall is only 8.8%, which is 43.6% less than the original wingsail lift reduction. As the bulge size increases the strength of the forward vortex created by the middle larger bulge increases, resulting in the absence of a symmetrical vortex structure on the suction surface of the wingsail, causing high fluid momentum band deflection. The energy of the boundary layer is supplemented by vorticity transport, promoting the formation of attached flow on the side of the smaller bulge and improving the lift coefficient. ]]></content:encoded> <dc:title>Study on Influence of Configuration of Bulges on Stall Characteristics of Two-Element Wingsails for Ships</dc:title> <dc:creator>Chen Li</dc:creator> <dc:creator>Binxin Wu</dc:creator> <dc:creator>Huabing Wen</dc:creator> <dc:creator>Junfu Yuan</dc:creator> <dc:identifier>doi: 10.3390/jmse13020337</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-12</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-12</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>337</prism:startingPage> <prism:doi>10.3390/jmse13020337</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/337</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/336"> <title>JMSE, Vol. 13, Pages 336: Similarity Principle for Ship Plate Structures</title> <link>https://www.mdpi.com/2077-1312/13/2/336</link> <description>The similarity principle serves as the theoretical foundation for experimental research on scaled ship structures. While extensive studies have been conducted on global longitudinal responses using scaled hydroelastic segmented ship models, there is a notable gap in experimental research on scaled local ship plate structures. This research introduces a novel composite similarity principle tailored for local ship plate structures, drawing upon classical beam and plate theories. We propose a design methodology to determine the appropriate scaled model for ship plate structures. To validate our proposed similarity principle and its associated design method, we present several numerical experiments. These methods are not only expected to inform future experimental design for local ship plate structures but also to enhance the current experimental framework, contributing to a more holistic approach to experimental, structural ship research.</description> <pubDate>2025-02-12</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 336: Similarity Principle for Ship Plate Structures Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/336">doi: 10.3390/jmse13020336</a> Authors: Haicheng Yu Songhao Wu Wenlong Liu Haiyi Yang The similarity principle serves as the theoretical foundation for experimental research on scaled ship structures. While extensive studies have been conducted on global longitudinal responses using scaled hydroelastic segmented ship models, there is a notable gap in experimental research on scaled local ship plate structures. This research introduces a novel composite similarity principle tailored for local ship plate structures, drawing upon classical beam and plate theories. We propose a design methodology to determine the appropriate scaled model for ship plate structures. To validate our proposed similarity principle and its associated design method, we present several numerical experiments. These methods are not only expected to inform future experimental design for local ship plate structures but also to enhance the current experimental framework, contributing to a more holistic approach to experimental, structural ship research. ]]></content:encoded> <dc:title>Similarity Principle for Ship Plate Structures</dc:title> <dc:creator>Haicheng Yu</dc:creator> <dc:creator>Songhao Wu</dc:creator> <dc:creator>Wenlong Liu</dc:creator> <dc:creator>Haiyi Yang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020336</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-12</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-12</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>336</prism:startingPage> <prism:doi>10.3390/jmse13020336</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/336</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/335"> <title>JMSE, Vol. 13, Pages 335: Geometry, Morphology, Physical Properties and Structure of Sea Ice Ridges During the Transition Period from First-Year to Second-Year in the Summer 2023 and 2024</title> <link>https://www.mdpi.com/2077-1312/13/2/335</link> <description>Summer processes in sea ice and their influence on the ridge action of structures in industrial areas are still rarely studied but of high interest. This article analyses data from two expeditions, the multidisciplinary GoNorth 2023 in the Arctic and the NPI Fram Strait 2024 cruise, combined with detailed analysis along the ridge keel and calculation of limit stress on vertical structures. The ice ridges were investigated by drilling cross-sections and sampling cores for temperature, salinity and density measurements. The keel depth ranged from 3.0 m to 4.8 m and the sail height ranged from 0.3 m to 0.9 m. The mean density and salinity of the ridge samples in 2023 were 899 kg/m3 and 2.2 ppt, respectively, and the mean salinity in 2024 was 2.0 ppt. The average constant temperature in the keel was &amp;minus;1.7 &amp;deg;C in 2023 and &amp;minus;1.6 &amp;deg;C in 2024. The upper limit of the strength of ridged ice on a vertical structure of 7.2 m in width ranged from 3.1 to 4.1 MPa. These results contribute to the knowledge of summer consolidation processes and are useful for statistical analysis of ice ridge loads exerted on offshore structures by drifting ice ridges.</description> <pubDate>2025-02-12</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 335: Geometry, Morphology, Physical Properties and Structure of Sea Ice Ridges During the Transition Period from First-Year to Second-Year in the Summer 2023 and 2024 Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/335">doi: 10.3390/jmse13020335</a> Authors: Alexandra Pliss Knut Vilhelm H酶yland Bernt Johan Leira Summer processes in sea ice and their influence on the ridge action of structures in industrial areas are still rarely studied but of high interest. This article analyses data from two expeditions, the multidisciplinary GoNorth 2023 in the Arctic and the NPI Fram Strait 2024 cruise, combined with detailed analysis along the ridge keel and calculation of limit stress on vertical structures. The ice ridges were investigated by drilling cross-sections and sampling cores for temperature, salinity and density measurements. The keel depth ranged from 3.0 m to 4.8 m and the sail height ranged from 0.3 m to 0.9 m. The mean density and salinity of the ridge samples in 2023 were 899 kg/m3 and 2.2 ppt, respectively, and the mean salinity in 2024 was 2.0 ppt. The average constant temperature in the keel was &amp;minus;1.7 &amp;deg;C in 2023 and &amp;minus;1.6 &amp;deg;C in 2024. The upper limit of the strength of ridged ice on a vertical structure of 7.2 m in width ranged from 3.1 to 4.1 MPa. These results contribute to the knowledge of summer consolidation processes and are useful for statistical analysis of ice ridge loads exerted on offshore structures by drifting ice ridges. ]]></content:encoded> <dc:title>Geometry, Morphology, Physical Properties and Structure of Sea Ice Ridges During the Transition Period from First-Year to Second-Year in the Summer 2023 and 2024</dc:title> <dc:creator>Alexandra Pliss</dc:creator> <dc:creator>Knut Vilhelm H酶yland</dc:creator> <dc:creator>Bernt Johan Leira</dc:creator> <dc:identifier>doi: 10.3390/jmse13020335</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-12</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-12</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>335</prism:startingPage> <prism:doi>10.3390/jmse13020335</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/335</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/334"> <title>JMSE, Vol. 13, Pages 334: Interannual Characteristics of Tropical Cyclones in Northwestern Pacific Region in Context of Warm Pool and Monsoon Troughs</title> <link>https://www.mdpi.com/2077-1312/13/2/334</link> <description>This study utilizes the typhoon path ensemble dataset from the Marine Science Big Data Center, surface temperature data from NOAA&amp;rsquo;s COBE Sea Surface Temperature dataset, and wind field data from the NCEP/DOE Reanalysis II dataset. It employs analytical techniques such as wavelet analysis, correlation analysis, and the Mann&amp;ndash;Kendall test to investigate the temporal and spatial variations in tropical cyclones in the Northwest Pacific, focusing on aspects such as frequency, genesis regions, and Accumulated Cyclone Energy. The research examines the influence of environmental factors, including warm pool thermal conditions and monsoon troughs, on the behavior of tropical cyclones. Findings indicate that over the past 39 years, there has been an upward trend in the frequency of tropical cyclones, whereas ACE has exhibited a slight downward trend. The results of the M-K test suggest that following a period of rapid increase, cyclone frequency experienced a significant shift in 1996, subsequently displaying a downward trend. Notably, the frequency of cyclones aligns with mutation points corresponding to warm pool thermal conditions and the Monsoon Trough Index. Wavelet analysis reveals that cyclone frequency, ACE, warm pool thermal conditions, and MTI exhibit similar small scale periodic variations. The observed differences in the genesis regions of tropical cyclones are attributed to fluctuations in warm pool thermal conditions. Specifically, years characterized by cooler warm pool conditions correspond with a stronger MTI, while warmer conditions are associated with a weaker MTI. The genesis regions of cyclones predominantly lie within the monsoon trough, where environmental conditions favorable for cyclone development are intensified during years of cooler warm pool conditions, resulting in heightened convective activity.</description> <pubDate>2025-02-12</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 334: Interannual Characteristics of Tropical Cyclones in Northwestern Pacific Region in Context of Warm Pool and Monsoon Troughs Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/334">doi: 10.3390/jmse13020334</a> Authors: Junru Guo Shichao Wang Xin He Jun Song Yanzhao Fu Yu Cai This study utilizes the typhoon path ensemble dataset from the Marine Science Big Data Center, surface temperature data from NOAA&amp;rsquo;s COBE Sea Surface Temperature dataset, and wind field data from the NCEP/DOE Reanalysis II dataset. It employs analytical techniques such as wavelet analysis, correlation analysis, and the Mann&amp;ndash;Kendall test to investigate the temporal and spatial variations in tropical cyclones in the Northwest Pacific, focusing on aspects such as frequency, genesis regions, and Accumulated Cyclone Energy. The research examines the influence of environmental factors, including warm pool thermal conditions and monsoon troughs, on the behavior of tropical cyclones. Findings indicate that over the past 39 years, there has been an upward trend in the frequency of tropical cyclones, whereas ACE has exhibited a slight downward trend. The results of the M-K test suggest that following a period of rapid increase, cyclone frequency experienced a significant shift in 1996, subsequently displaying a downward trend. Notably, the frequency of cyclones aligns with mutation points corresponding to warm pool thermal conditions and the Monsoon Trough Index. Wavelet analysis reveals that cyclone frequency, ACE, warm pool thermal conditions, and MTI exhibit similar small scale periodic variations. The observed differences in the genesis regions of tropical cyclones are attributed to fluctuations in warm pool thermal conditions. Specifically, years characterized by cooler warm pool conditions correspond with a stronger MTI, while warmer conditions are associated with a weaker MTI. The genesis regions of cyclones predominantly lie within the monsoon trough, where environmental conditions favorable for cyclone development are intensified during years of cooler warm pool conditions, resulting in heightened convective activity. ]]></content:encoded> <dc:title>Interannual Characteristics of Tropical Cyclones in Northwestern Pacific Region in Context of Warm Pool and Monsoon Troughs</dc:title> <dc:creator>Junru Guo</dc:creator> <dc:creator>Shichao Wang</dc:creator> <dc:creator>Xin He</dc:creator> <dc:creator>Jun Song</dc:creator> <dc:creator>Yanzhao Fu</dc:creator> <dc:creator>Yu Cai</dc:creator> <dc:identifier>doi: 10.3390/jmse13020334</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-12</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-12</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>334</prism:startingPage> <prism:doi>10.3390/jmse13020334</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/334</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/333"> <title>JMSE, Vol. 13, Pages 333: Research on Ellipse-Based Transient Impact Source Localization Methodology for Ship Cabin Structure</title> <link>https://www.mdpi.com/2077-1312/13/2/333</link> <description>This study explores the application of three localization methods in identifying transient impact sources in the ship cabin structure. These methods examined are based on energy curvature and cumulative error, time-reversed virtual focusing triangulation, and energy correlation localization. It presents an elliptical region-based transient impact source localization technique for the ship cabin structure. The center of the elliptical region is determined by calculating the arithmetic mean of the position coordinates obtained from three methods, and the long and short semi-axes of the ellipse are defined as three times the standard deviations in the horizontal and vertical directions, respectively, to construct an elliptical localization area for precise positioning. Experimental results indicate that the average error distance of this impact localization technique is 0.10 m, with the predicted position error of 22 impact points being 0 m. Among 15 impact points, 14 impact points have error distances ranging from 0 m to 0.40 m, while 1 impact point has an error distance of 1.08 m, primarily due to the weak connection between sensors and the ship cabin structure. The overall localization error of the ship cabin structure is low, meeting the required localization accuracy.</description> <pubDate>2025-02-12</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 333: Research on Ellipse-Based Transient Impact Source Localization Methodology for Ship Cabin Structure Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/333">doi: 10.3390/jmse13020333</a> Authors: Xiufeng Huang Rongwu Xu Wenjing Yu Xuan Ming Shiji Wu This study explores the application of three localization methods in identifying transient impact sources in the ship cabin structure. These methods examined are based on energy curvature and cumulative error, time-reversed virtual focusing triangulation, and energy correlation localization. It presents an elliptical region-based transient impact source localization technique for the ship cabin structure. The center of the elliptical region is determined by calculating the arithmetic mean of the position coordinates obtained from three methods, and the long and short semi-axes of the ellipse are defined as three times the standard deviations in the horizontal and vertical directions, respectively, to construct an elliptical localization area for precise positioning. Experimental results indicate that the average error distance of this impact localization technique is 0.10 m, with the predicted position error of 22 impact points being 0 m. Among 15 impact points, 14 impact points have error distances ranging from 0 m to 0.40 m, while 1 impact point has an error distance of 1.08 m, primarily due to the weak connection between sensors and the ship cabin structure. The overall localization error of the ship cabin structure is low, meeting the required localization accuracy. ]]></content:encoded> <dc:title>Research on Ellipse-Based Transient Impact Source Localization Methodology for Ship Cabin Structure</dc:title> <dc:creator>Xiufeng Huang</dc:creator> <dc:creator>Rongwu Xu</dc:creator> <dc:creator>Wenjing Yu</dc:creator> <dc:creator>Xuan Ming</dc:creator> <dc:creator>Shiji Wu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020333</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-12</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-12</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>333</prism:startingPage> <prism:doi>10.3390/jmse13020333</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/333</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/331"> <title>JMSE, Vol. 13, Pages 331: CNN-GRU-ATT Method for Resistivity Logging Curve Reconstruction and Fluid Property Identification in Marine Carbonate Reservoirs</title> <link>https://www.mdpi.com/2077-1312/13/2/331</link> <description>Geophysical logging curves are crucial for oil and gas field exploration and development, and curve reconstruction techniques are a key focus of research in this field. This study proposes an inversion model for deep resistivity curves in marine carbonate reservoirs, specifically the Mishrif Formation of the Halfaya Field, by integrating a deep learning model called CNN-GRU-ATT, which combines Convolutional Neural Networks (CNN), Gated Recurrent Units (GRU), and the Attention Mechanism (ATT). Using logging data from the marine carbonate oil layers, the reconstructed deep resistivity curve is compared with actual measurements to determine reservoir fluid properties. The results demonstrate the effectiveness of the CNN-GRU-ATT model in accurately reconstructing deep resistivity curves for carbonate reservoirs within the Mishrif Formation. Notably, the model outperforms alternative methods such as CNN-GRU, GRU, Long Short-Term Memory (LSTM), Multiple Regression, and Random Forest in new wells, exhibiting high accuracy and robust generalization capabilities. In practical applications, the response of the inverted deep resistivity curve can be utilized to identify the reservoir water cut. Specifically, when the model-inverted curve exhibits a higher response compared to the measured curve, it indicates the presence of reservoir water. Additionally, a stable relative position between the two curves suggests the presence of a water layer. Utilizing this method, the oil&amp;ndash;water transition zone can be accurately delineated, achieving a fluid property identification accuracy of 93.14%. This study not only introduces a novel curve reconstruction method but also presents a precise approach to identifying reservoir fluid properties. These findings establish a solid technical foundation for decision-making support in oilfield development.</description> <pubDate>2025-02-12</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 331: CNN-GRU-ATT Method for Resistivity Logging Curve Reconstruction and Fluid Property Identification in Marine Carbonate Reservoirs Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/331">doi: 10.3390/jmse13020331</a> Authors: Jianhong Guo Hengyang Lv Qing Zhao Yuxin Yang Zuomin Zhu Zhansong Zhang Geophysical logging curves are crucial for oil and gas field exploration and development, and curve reconstruction techniques are a key focus of research in this field. This study proposes an inversion model for deep resistivity curves in marine carbonate reservoirs, specifically the Mishrif Formation of the Halfaya Field, by integrating a deep learning model called CNN-GRU-ATT, which combines Convolutional Neural Networks (CNN), Gated Recurrent Units (GRU), and the Attention Mechanism (ATT). Using logging data from the marine carbonate oil layers, the reconstructed deep resistivity curve is compared with actual measurements to determine reservoir fluid properties. The results demonstrate the effectiveness of the CNN-GRU-ATT model in accurately reconstructing deep resistivity curves for carbonate reservoirs within the Mishrif Formation. Notably, the model outperforms alternative methods such as CNN-GRU, GRU, Long Short-Term Memory (LSTM), Multiple Regression, and Random Forest in new wells, exhibiting high accuracy and robust generalization capabilities. In practical applications, the response of the inverted deep resistivity curve can be utilized to identify the reservoir water cut. Specifically, when the model-inverted curve exhibits a higher response compared to the measured curve, it indicates the presence of reservoir water. Additionally, a stable relative position between the two curves suggests the presence of a water layer. Utilizing this method, the oil&amp;ndash;water transition zone can be accurately delineated, achieving a fluid property identification accuracy of 93.14%. This study not only introduces a novel curve reconstruction method but also presents a precise approach to identifying reservoir fluid properties. These findings establish a solid technical foundation for decision-making support in oilfield development. ]]></content:encoded> <dc:title>CNN-GRU-ATT Method for Resistivity Logging Curve Reconstruction and Fluid Property Identification in Marine Carbonate Reservoirs</dc:title> <dc:creator>Jianhong Guo</dc:creator> <dc:creator>Hengyang Lv</dc:creator> <dc:creator>Qing Zhao</dc:creator> <dc:creator>Yuxin Yang</dc:creator> <dc:creator>Zuomin Zhu</dc:creator> <dc:creator>Zhansong Zhang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020331</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-12</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-12</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>331</prism:startingPage> <prism:doi>10.3390/jmse13020331</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/331</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/332"> <title>JMSE, Vol. 13, Pages 332: Earth System Modeling, Data Assimilation, Artificial Intelligence, Deep Learning and Ocean Information Engineering II</title> <link>https://www.mdpi.com/2077-1312/13/2/332</link> <description>The ways in which artificial intelligence, especially deep learning (AIDL) or data-driven methods, can be used to advance sciences are an important and critical topic in the current research landscape [...]</description> <pubDate>2025-02-12</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 332: Earth System Modeling, Data Assimilation, Artificial Intelligence, Deep Learning and Ocean Information Engineering II Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/332">doi: 10.3390/jmse13020332</a> Authors: Shaoqing Zhang Yuxin Zhao Hao Zuo Junyu Dong The ways in which artificial intelligence, especially deep learning (AIDL) or data-driven methods, can be used to advance sciences are an important and critical topic in the current research landscape [...] ]]></content:encoded> <dc:title>Earth System Modeling, Data Assimilation, Artificial Intelligence, Deep Learning and Ocean Information Engineering II</dc:title> <dc:creator>Shaoqing Zhang</dc:creator> <dc:creator>Yuxin Zhao</dc:creator> <dc:creator>Hao Zuo</dc:creator> <dc:creator>Junyu Dong</dc:creator> <dc:identifier>doi: 10.3390/jmse13020332</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-12</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-12</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Editorial</prism:section> <prism:startingPage>332</prism:startingPage> <prism:doi>10.3390/jmse13020332</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/332</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/329"> <title>JMSE, Vol. 13, Pages 329: Establishment of the Unified Maneuvering and Seakeeping Dynamic Model for Submarines Moving in Horizontal Plane near Free Surface</title> <link>https://www.mdpi.com/2077-1312/13/2/329</link> <description>When a submarine moves near the free surface, the lift and drag characteristics that act on it are different compared to when in deep water; for example, waves on the free surface cause submarine motions that are not seen in deep water conditions and lead to changes in speed, fuel efficiency, safety, and maneuverability. To accurately predict the maneuverability of a submarine, it is necessary to consider how both maneuvering and seakeeping performance are affected by free-surface effects during the design stage. In this study, the unified maneuvering and seakeeping dynamic model is proposed. In the maneuvering performance analysis, hydrodynamic forces in the horizontal plane were calculated using STAR-CCM+. In the seakeeping performance analysis, the 6-DOF motions of the submarine and the mean wave drift forces in the horizontal plane were calculated using Ansys AQWA. Since the maneuvering motion component has a relatively long period and the seakeeping motion component has a relatively short period, the unified maneuvering and seakeeping dynamic model for a submarine moving near the surface was established using a two-time-scale approach. Using the established unified maneuvering and seakeeping dynamic model, turning circle simulations were performed in both calm water and in waves. In calm water, there were no significant differences as depth was varied. However, in irregular waves, significant differences were found in the trajectories and motion variables as depth varied. These findings underscore the necessity of accounting for sea surface conditions when operating near the free surface to ensure safety and avoid potentially hazardous scenarios during submarine operations.</description> <pubDate>2025-02-11</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 329: Establishment of the Unified Maneuvering and Seakeeping Dynamic Model for Submarines Moving in Horizontal Plane near Free Surface Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/329">doi: 10.3390/jmse13020329</a> Authors: Aeri Cho Hoang Thien Vu Tien Long Bien Hyeon Kyu Yoon Anh Khoa Vo Thi Thanh Diep Nguyen When a submarine moves near the free surface, the lift and drag characteristics that act on it are different compared to when in deep water; for example, waves on the free surface cause submarine motions that are not seen in deep water conditions and lead to changes in speed, fuel efficiency, safety, and maneuverability. To accurately predict the maneuverability of a submarine, it is necessary to consider how both maneuvering and seakeeping performance are affected by free-surface effects during the design stage. In this study, the unified maneuvering and seakeeping dynamic model is proposed. In the maneuvering performance analysis, hydrodynamic forces in the horizontal plane were calculated using STAR-CCM+. In the seakeeping performance analysis, the 6-DOF motions of the submarine and the mean wave drift forces in the horizontal plane were calculated using Ansys AQWA. Since the maneuvering motion component has a relatively long period and the seakeeping motion component has a relatively short period, the unified maneuvering and seakeeping dynamic model for a submarine moving near the surface was established using a two-time-scale approach. Using the established unified maneuvering and seakeeping dynamic model, turning circle simulations were performed in both calm water and in waves. In calm water, there were no significant differences as depth was varied. However, in irregular waves, significant differences were found in the trajectories and motion variables as depth varied. These findings underscore the necessity of accounting for sea surface conditions when operating near the free surface to ensure safety and avoid potentially hazardous scenarios during submarine operations. ]]></content:encoded> <dc:title>Establishment of the Unified Maneuvering and Seakeeping Dynamic Model for Submarines Moving in Horizontal Plane near Free Surface</dc:title> <dc:creator>Aeri Cho</dc:creator> <dc:creator>Hoang Thien Vu</dc:creator> <dc:creator>Tien Long Bien</dc:creator> <dc:creator>Hyeon Kyu Yoon</dc:creator> <dc:creator>Anh Khoa Vo</dc:creator> <dc:creator>Thi Thanh Diep Nguyen</dc:creator> <dc:identifier>doi: 10.3390/jmse13020329</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-11</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-11</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>329</prism:startingPage> <prism:doi>10.3390/jmse13020329</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/329</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/330"> <title>JMSE, Vol. 13, Pages 330: Analysis of Interference Magnetic Field Characteristics of Underwater Gliders</title> <link>https://www.mdpi.com/2077-1312/13/2/330</link> <description>Underwater gliders are a new type of unmanned underwater vehicle, characterized by high energy efficiency, long endurance, and low operational costs. They hold broad application prospects in fields such as ocean exploration, resource surveying, maritime surveillance, and military defense. This paper takes underwater gliders as the research subject, analyzing the characteristics of magnetic interference signals under different operational conditions. The study found that during full operational states, the motor&amp;rsquo;s operation generates interference signals at 17 Hz; during attitude adjustment, the movement of the moving block generates significant interference magnetic fields, especially during the forward and backward motion of the block, where interference signals at 20 Hz are particularly pronounced. To meet the objective of equipping underwater gliders with magnetic field sensors for underwater target detection, this paper proposes an adaptive filtering method based on the Recursive Least Squares (RLS) algorithm. The experimental results indicate that after filtering with the RLS algorithm, the amplitude of the noise signal has been reduced by over 60%, and it can effectively eliminate the noise components at 17 Hz and 20 Hz caused by the glider&amp;rsquo;s motor. This algorithm achieves an average increase in the signal-to-noise ratio (SNR) of 12 dB, which is equivalent to an approximately 80% improvement in accuracy. It significantly enhances the stability and signal-to-noise ratio of the magnetic field signals of underwater targets. This provides a feasible solution for equipping underwater gliders with magnetic field sensors for underwater target detection, holding important practical engineering significance.</description> <pubDate>2025-02-11</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 330: Analysis of Interference Magnetic Field Characteristics of Underwater Gliders Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/330">doi: 10.3390/jmse13020330</a> Authors: Taotao Xie Dawei Xiao Jiawei Zhang Qing Ji Underwater gliders are a new type of unmanned underwater vehicle, characterized by high energy efficiency, long endurance, and low operational costs. They hold broad application prospects in fields such as ocean exploration, resource surveying, maritime surveillance, and military defense. This paper takes underwater gliders as the research subject, analyzing the characteristics of magnetic interference signals under different operational conditions. The study found that during full operational states, the motor&amp;rsquo;s operation generates interference signals at 17 Hz; during attitude adjustment, the movement of the moving block generates significant interference magnetic fields, especially during the forward and backward motion of the block, where interference signals at 20 Hz are particularly pronounced. To meet the objective of equipping underwater gliders with magnetic field sensors for underwater target detection, this paper proposes an adaptive filtering method based on the Recursive Least Squares (RLS) algorithm. The experimental results indicate that after filtering with the RLS algorithm, the amplitude of the noise signal has been reduced by over 60%, and it can effectively eliminate the noise components at 17 Hz and 20 Hz caused by the glider&amp;rsquo;s motor. This algorithm achieves an average increase in the signal-to-noise ratio (SNR) of 12 dB, which is equivalent to an approximately 80% improvement in accuracy. It significantly enhances the stability and signal-to-noise ratio of the magnetic field signals of underwater targets. This provides a feasible solution for equipping underwater gliders with magnetic field sensors for underwater target detection, holding important practical engineering significance. ]]></content:encoded> <dc:title>Analysis of Interference Magnetic Field Characteristics of Underwater Gliders</dc:title> <dc:creator>Taotao Xie</dc:creator> <dc:creator>Dawei Xiao</dc:creator> <dc:creator>Jiawei Zhang</dc:creator> <dc:creator>Qing Ji</dc:creator> <dc:identifier>doi: 10.3390/jmse13020330</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-11</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-11</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>330</prism:startingPage> <prism:doi>10.3390/jmse13020330</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/330</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/328"> <title>JMSE, Vol. 13, Pages 328: A Novel Approach for the Systematic Evaluation and Optimization of Performance and Emissions in Hybrid Electric Propulsion Systems</title> <link>https://www.mdpi.com/2077-1312/13/2/328</link> <description>In the maritime industry, the adoption of hybrid electric propulsion systems aims to enhance energy efficiency and environmental sustainability. However, this study originates from the fundamental question: &amp;lsquo;Are hybrid systems truly environmentally friendly?&amp;rsquo; Ensuring optimal system performance requires accurate load analysis and an effective energy management system. Existing studies have limitations in addressing real-time load variability, long-term load patterns, and scalability across different operational conditions. To address these, this study proposes a standard load analyzer based on main engine power output data to conduct performance analysis. Using MATLAB/Simulink simulations and Excel VBA-based methods, the system evaluates key performance factors under various operational load conditions. Cross-validation between MATLAB and Excel ensured high accuracy, with a relative error rate below 0.01%. The results showed consistent performance indicators, offering reliable insights across vessel types and scenarios. The system&amp;rsquo;s lightweight design and rapid data acquisition enable effective energy management optimization. However, it has limitations in performing detailed analyses for life cycle assessment, operating expenditures, and capital expenditures. Future advancements in data consolidation and analytical methods will help the tool evolve into a comprehensive tool for multi-dimensional performance evaluation, addressing economic, environmental, and technical aspects.</description> <pubDate>2025-02-11</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 328: A Novel Approach for the Systematic Evaluation and Optimization of Performance and Emissions in Hybrid Electric Propulsion Systems Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/328">doi: 10.3390/jmse13020328</a> Authors: Jayoung Jung Hyeonmin Jeon Heemoon Kim SeongWan Kim In the maritime industry, the adoption of hybrid electric propulsion systems aims to enhance energy efficiency and environmental sustainability. However, this study originates from the fundamental question: &amp;lsquo;Are hybrid systems truly environmentally friendly?&amp;rsquo; Ensuring optimal system performance requires accurate load analysis and an effective energy management system. Existing studies have limitations in addressing real-time load variability, long-term load patterns, and scalability across different operational conditions. To address these, this study proposes a standard load analyzer based on main engine power output data to conduct performance analysis. Using MATLAB/Simulink simulations and Excel VBA-based methods, the system evaluates key performance factors under various operational load conditions. Cross-validation between MATLAB and Excel ensured high accuracy, with a relative error rate below 0.01%. The results showed consistent performance indicators, offering reliable insights across vessel types and scenarios. The system&amp;rsquo;s lightweight design and rapid data acquisition enable effective energy management optimization. However, it has limitations in performing detailed analyses for life cycle assessment, operating expenditures, and capital expenditures. Future advancements in data consolidation and analytical methods will help the tool evolve into a comprehensive tool for multi-dimensional performance evaluation, addressing economic, environmental, and technical aspects. ]]></content:encoded> <dc:title>A Novel Approach for the Systematic Evaluation and Optimization of Performance and Emissions in Hybrid Electric Propulsion Systems</dc:title> <dc:creator>Jayoung Jung</dc:creator> <dc:creator>Hyeonmin Jeon</dc:creator> <dc:creator>Heemoon Kim</dc:creator> <dc:creator>SeongWan Kim</dc:creator> <dc:identifier>doi: 10.3390/jmse13020328</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-11</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-11</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>328</prism:startingPage> <prism:doi>10.3390/jmse13020328</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/328</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/327"> <title>JMSE, Vol. 13, Pages 327: Real-Time Mooring Tension Prediction for Semi-Submersible Aquaculture Platforms by an EEMD-TCN-SA Neural Network Approach</title> <link>https://www.mdpi.com/2077-1312/13/2/327</link> <description>Precise prediction of mooring tension is essential for the safety and operational efficiency of semi-submersible aquaculture platforms. Traditional numerical methods struggle with real-time performance due to the nonlinear and dynamic characteristics of environmental loads. This study proposes a novel neural network approach to enhance real-time forecasting of mooring line responses, combining Ensemble Empirical Mode Decomposition (EEMD), Temporal Convolutional Networks (TCNs), and a Self-Attention (SA) mechanism. The training dataset encompasses time-domain analysis results, including mooring tensions, motion responses, and total structural forces. Firstly, Pearson Correlation Analysis (PCA) is utilized to assess the linear relationships among the hydrodynamic variables. Subsequently, EEMD is applied to decompose the mooring tension data, which is then combined with the highly correlated variables to form the input dataset. Finally, the TCN model is trained to predict the time series, while an SA mechanism is integrated to weigh the significance of different moments within the sequence, thereby further enhancing prediction accuracy. The results demonstrate that the evaluation metrics of the EEMD-TCN-SA model outperform those of other neural network models, effectively predicting mooring tension for semi-submersible platforms and significantly reducing prediction errors.</description> <pubDate>2025-02-11</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 327: Real-Time Mooring Tension Prediction for Semi-Submersible Aquaculture Platforms by an EEMD-TCN-SA Neural Network Approach Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/327">doi: 10.3390/jmse13020327</a> Authors: Changfeng Liu Yu Xin Yu Zhang Yutong Yang Lei Sun Changping Chen Precise prediction of mooring tension is essential for the safety and operational efficiency of semi-submersible aquaculture platforms. Traditional numerical methods struggle with real-time performance due to the nonlinear and dynamic characteristics of environmental loads. This study proposes a novel neural network approach to enhance real-time forecasting of mooring line responses, combining Ensemble Empirical Mode Decomposition (EEMD), Temporal Convolutional Networks (TCNs), and a Self-Attention (SA) mechanism. The training dataset encompasses time-domain analysis results, including mooring tensions, motion responses, and total structural forces. Firstly, Pearson Correlation Analysis (PCA) is utilized to assess the linear relationships among the hydrodynamic variables. Subsequently, EEMD is applied to decompose the mooring tension data, which is then combined with the highly correlated variables to form the input dataset. Finally, the TCN model is trained to predict the time series, while an SA mechanism is integrated to weigh the significance of different moments within the sequence, thereby further enhancing prediction accuracy. The results demonstrate that the evaluation metrics of the EEMD-TCN-SA model outperform those of other neural network models, effectively predicting mooring tension for semi-submersible platforms and significantly reducing prediction errors. ]]></content:encoded> <dc:title>Real-Time Mooring Tension Prediction for Semi-Submersible Aquaculture Platforms by an EEMD-TCN-SA Neural Network Approach</dc:title> <dc:creator>Changfeng Liu</dc:creator> <dc:creator>Yu Xin</dc:creator> <dc:creator>Yu Zhang</dc:creator> <dc:creator>Yutong Yang</dc:creator> <dc:creator>Lei Sun</dc:creator> <dc:creator>Changping Chen</dc:creator> <dc:identifier>doi: 10.3390/jmse13020327</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-11</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-11</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>327</prism:startingPage> <prism:doi>10.3390/jmse13020327</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/327</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/326"> <title>JMSE, Vol. 13, Pages 326: Buoy and Winch Collaborative Control System Based on Deep Reinforcement Learning</title> <link>https://www.mdpi.com/2077-1312/13/2/326</link> <description>The improved control performance of the buoy and winch collaborative control system can enhance the stability of the connection between underwater robots and ground industrial control equipment. To overcome the challenge of mathematical modeling of this control system, this research introduces reinforcement learning and transformer models in the design process. The main contributions include the development of two simulation environments for training DRL agents, designing a reward function to guide the exploration process, proposing a buoy control algorithm based on the discrete soft actor-critic (SAC) algorithm, and proposing a winch cable length prediction algorithm based on a lightweight transformer model. The experiment results demonstrated significant improvements in rewards diagrams, buoy control trajectories, and winch model performance, showcasing the effectiveness of our proposed system. The average error of the buoy tracking trajectories induced by different policies trained in the two environments is less than 0.05, and the evaluation error of the behavior cloning lightweight transformer model is less than 0.03.</description> <pubDate>2025-02-11</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 326: Buoy and Winch Collaborative Control System Based on Deep Reinforcement Learning Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/326">doi: 10.3390/jmse13020326</a> Authors: Yang Gu Jianjun Ni Zaiming Geng Bing Zhao Haowen Yang The improved control performance of the buoy and winch collaborative control system can enhance the stability of the connection between underwater robots and ground industrial control equipment. To overcome the challenge of mathematical modeling of this control system, this research introduces reinforcement learning and transformer models in the design process. The main contributions include the development of two simulation environments for training DRL agents, designing a reward function to guide the exploration process, proposing a buoy control algorithm based on the discrete soft actor-critic (SAC) algorithm, and proposing a winch cable length prediction algorithm based on a lightweight transformer model. The experiment results demonstrated significant improvements in rewards diagrams, buoy control trajectories, and winch model performance, showcasing the effectiveness of our proposed system. The average error of the buoy tracking trajectories induced by different policies trained in the two environments is less than 0.05, and the evaluation error of the behavior cloning lightweight transformer model is less than 0.03. ]]></content:encoded> <dc:title>Buoy and Winch Collaborative Control System Based on Deep Reinforcement Learning</dc:title> <dc:creator>Yang Gu</dc:creator> <dc:creator>Jianjun Ni</dc:creator> <dc:creator>Zaiming Geng</dc:creator> <dc:creator>Bing Zhao</dc:creator> <dc:creator>Haowen Yang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020326</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-11</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-11</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>326</prism:startingPage> <prism:doi>10.3390/jmse13020326</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/326</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/325"> <title>JMSE, Vol. 13, Pages 325: Enhancement Strategy for Port Resilience: Shipping Route Optimization Methods Based on Network Characteristics of Ports</title> <link>https://www.mdpi.com/2077-1312/13/2/325</link> <description>Ports and their affiliated shipping routes are fundamental to the maritime logistics system, crucial for global trade. However, they face risks from natural disasters and human-induced crises. Enhancing port resilience, the ability to quickly recover and maintain operations during disruptions is vital for a robust maritime network. This study focuses on enhancing port resilience by improving the shipping route network, using an innovative link-prediction-based approach. Initially, a multi-dimensional resilience analysis is conducted to identify key low-resilience and bottleneck ports, guiding targeted network optimizations. Then, a novel link prediction algorithm is applied to find potential new shipping connections, significantly enhancing network efficiency, robustness, and port resilience. The optimized network effectively improves the connectivity of critical low-resilience ports with central hub ports and bottleneck ports with surrounding ones. Route diversification mitigates risks and strengthens overall resilience. Key low-resilience ports and bottleneck ports are reduced by an average of 20% and 25%. Finally, practical strategies are proposed. Low-resilience ports should establish direct connections with major hubs, and regional sub-networks can offer support. For bottleneck ports, additional secondary and short distance links should be added to transform them into more integrated hubs, enhancing the network&amp;rsquo;s robustness. These strategies improve the network&amp;rsquo;s operational capacity during crises, ensuring efficient cargo flow.</description> <pubDate>2025-02-10</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 325: Enhancement Strategy for Port Resilience: Shipping Route Optimization Methods Based on Network Characteristics of Ports Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/325">doi: 10.3390/jmse13020325</a> Authors: Xiang Yuan Xinhao He Ports and their affiliated shipping routes are fundamental to the maritime logistics system, crucial for global trade. However, they face risks from natural disasters and human-induced crises. Enhancing port resilience, the ability to quickly recover and maintain operations during disruptions is vital for a robust maritime network. This study focuses on enhancing port resilience by improving the shipping route network, using an innovative link-prediction-based approach. Initially, a multi-dimensional resilience analysis is conducted to identify key low-resilience and bottleneck ports, guiding targeted network optimizations. Then, a novel link prediction algorithm is applied to find potential new shipping connections, significantly enhancing network efficiency, robustness, and port resilience. The optimized network effectively improves the connectivity of critical low-resilience ports with central hub ports and bottleneck ports with surrounding ones. Route diversification mitigates risks and strengthens overall resilience. Key low-resilience ports and bottleneck ports are reduced by an average of 20% and 25%. Finally, practical strategies are proposed. Low-resilience ports should establish direct connections with major hubs, and regional sub-networks can offer support. For bottleneck ports, additional secondary and short distance links should be added to transform them into more integrated hubs, enhancing the network&amp;rsquo;s robustness. These strategies improve the network&amp;rsquo;s operational capacity during crises, ensuring efficient cargo flow. ]]></content:encoded> <dc:title>Enhancement Strategy for Port Resilience: Shipping Route Optimization Methods Based on Network Characteristics of Ports</dc:title> <dc:creator>Xiang Yuan</dc:creator> <dc:creator>Xinhao He</dc:creator> <dc:identifier>doi: 10.3390/jmse13020325</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-10</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-10</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>325</prism:startingPage> <prism:doi>10.3390/jmse13020325</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/325</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/323"> <title>JMSE, Vol. 13, Pages 323: CFD Design Optimisation for the Hydrodynamic Performance of the Novel Fin-Ring Horizontal Axis Hydrokinetic Turbine</title> <link>https://www.mdpi.com/2077-1312/13/2/323</link> <description>In this paper, the aim is to optimise the hydrodynamic performance of the novel fin-ring horizontal axis hydrokinetic turbine (HAHK). The original unique fin-ring turbine is an unconventional marine current turbine that comprises seven concentric rings with 88 connecting cambered fins and a solid centre hub. To begin with, the hydrodynamic performance of the benchmark turbine is evaluated using CFD simulations and is validated against sea-test data available in the literature. Subsequently, three of the turbine design parameters, namely, the fins&amp;rsquo; pitch angle, the fins&amp;rsquo; camber length, and the fins&amp;rsquo; aspect ratio, are optimised for maximum power generation. Further test simulations illustrated the existence of a laminar region of flow in the turbine flow field. The K-kL-&amp;omega; transition-sensitive turbulence model is adopted to capture the influence of transition on the flow field with results compared against those of the fully turbulent K-&amp;epsilon; turbulence model. A final fine-tuning in the turbine design is carried out by increasing the number of fins per ring in the outermost rings to further maximise the generated power. The turbine hydrodynamic performance is assessed by comparison against other conventional hydrokinetic turbines available in the literature. Very satisfactory results are obtained with an increase of about 35% in the turbine-generated CP as compared to that of the benchmark turbine. The turbine performance compares very well with other conventional turbines, especially in terms of higher peak CP values, wider operating TSR range, and less sensitivity to variations in the inflow current speeds.</description> <pubDate>2025-02-10</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 323: CFD Design Optimisation for the Hydrodynamic Performance of the Novel Fin-Ring Horizontal Axis Hydrokinetic Turbine Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/323">doi: 10.3390/jmse13020323</a> Authors: Mahmoud I. Ibrahim Mar铆a J. Legaz Adel A. Banawan Tamer M. Ahmed In this paper, the aim is to optimise the hydrodynamic performance of the novel fin-ring horizontal axis hydrokinetic turbine (HAHK). The original unique fin-ring turbine is an unconventional marine current turbine that comprises seven concentric rings with 88 connecting cambered fins and a solid centre hub. To begin with, the hydrodynamic performance of the benchmark turbine is evaluated using CFD simulations and is validated against sea-test data available in the literature. Subsequently, three of the turbine design parameters, namely, the fins&amp;rsquo; pitch angle, the fins&amp;rsquo; camber length, and the fins&amp;rsquo; aspect ratio, are optimised for maximum power generation. Further test simulations illustrated the existence of a laminar region of flow in the turbine flow field. The K-kL-&amp;omega; transition-sensitive turbulence model is adopted to capture the influence of transition on the flow field with results compared against those of the fully turbulent K-&amp;epsilon; turbulence model. A final fine-tuning in the turbine design is carried out by increasing the number of fins per ring in the outermost rings to further maximise the generated power. The turbine hydrodynamic performance is assessed by comparison against other conventional hydrokinetic turbines available in the literature. Very satisfactory results are obtained with an increase of about 35% in the turbine-generated CP as compared to that of the benchmark turbine. The turbine performance compares very well with other conventional turbines, especially in terms of higher peak CP values, wider operating TSR range, and less sensitivity to variations in the inflow current speeds. ]]></content:encoded> <dc:title>CFD Design Optimisation for the Hydrodynamic Performance of the Novel Fin-Ring Horizontal Axis Hydrokinetic Turbine</dc:title> <dc:creator>Mahmoud I. Ibrahim</dc:creator> <dc:creator>Mar铆a J. Legaz</dc:creator> <dc:creator>Adel A. Banawan</dc:creator> <dc:creator>Tamer M. Ahmed</dc:creator> <dc:identifier>doi: 10.3390/jmse13020323</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-10</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-10</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>323</prism:startingPage> <prism:doi>10.3390/jmse13020323</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/323</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/324"> <title>JMSE, Vol. 13, Pages 324: New Challenges in Marine Aquaculture Research</title> <link>https://www.mdpi.com/2077-1312/13/2/324</link> <description>Marine aquaculture has witnessed remarkable growth in recent decades, contributing significantly to global food security and economic development [...]</description> <pubDate>2025-02-10</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 324: New Challenges in Marine Aquaculture Research Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/324">doi: 10.3390/jmse13020324</a> Authors: Ana Catarina Matias Carlos Andrade Marine aquaculture has witnessed remarkable growth in recent decades, contributing significantly to global food security and economic development [...] ]]></content:encoded> <dc:title>New Challenges in Marine Aquaculture Research</dc:title> <dc:creator>Ana Catarina Matias</dc:creator> <dc:creator>Carlos Andrade</dc:creator> <dc:identifier>doi: 10.3390/jmse13020324</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-10</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-10</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Editorial</prism:section> <prism:startingPage>324</prism:startingPage> <prism:doi>10.3390/jmse13020324</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/324</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/322"> <title>JMSE, Vol. 13, Pages 322: Reconstruction of the Cenozoic Deformation of the Yinggehai Basin and Beibu Gulf Basin, South China Sea</title> <link>https://www.mdpi.com/2077-1312/13/2/322</link> <description>This study employs structural information and stratigraphic lithology as constraints to conduct balanced restoration on seismic profiles from the Yinggehai Basin (YGB) and the Beibu Gulf Basin (BGB). The reconstruction indicates that the evolutionary periods of the YGB can be classified into five distinct stages: rift stage (56&amp;ndash;36 Ma), fault depression stage (36&amp;ndash;23 Ma), depression stage (23&amp;ndash;15.5 Ma), inversion stage (15.5&amp;ndash;5.3 Ma), and depression stage (5.3&amp;ndash;0 Ma). In contrast, the evolutionary stages of the BGB are categorized into four stages: rift stage (66&amp;ndash;56 Ma), fault depression stage (40&amp;ndash;32 Ma), fault-depression transition stage (32&amp;ndash;23 Ma), and depression stage (23&amp;ndash;0 Ma). The BGB did not experience a tectonic inversion phase similar to that of the YGB, but both have undergone a fault depression stage under the same tectonic background. The rotational extrusion of the Indochina block has accelerated the opening of the rift basins along the northern and western margins of the South China Sea (SCS). The dual subduction processes of the Proto-SCS has led to the opening of the SCS Basin. Within the BGB, a significant increase in the dilatation strain rate (DSR) can be observed over a large area. The transition in the strike-slip nature of the Red River Fault Zone is evidenced by tectonic inversion in the stratigraphy. The tectonic mechanism of the YGB is primarily controlled by the convergence of the India-Eurasia plate, while the evolution of the BGB is governed by the subduction of the Pacific plate, the convergence of the India-Eurasia plate, and the dual subduction of the Proto-SCS.</description> <pubDate>2025-02-10</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 322: Reconstruction of the Cenozoic Deformation of the Yinggehai Basin and Beibu Gulf Basin, South China Sea Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/322">doi: 10.3390/jmse13020322</a> Authors: Jiaxiao Zhao Chenghao Liu Jingjin Zhao Qingjun Xu This study employs structural information and stratigraphic lithology as constraints to conduct balanced restoration on seismic profiles from the Yinggehai Basin (YGB) and the Beibu Gulf Basin (BGB). The reconstruction indicates that the evolutionary periods of the YGB can be classified into five distinct stages: rift stage (56&amp;ndash;36 Ma), fault depression stage (36&amp;ndash;23 Ma), depression stage (23&amp;ndash;15.5 Ma), inversion stage (15.5&amp;ndash;5.3 Ma), and depression stage (5.3&amp;ndash;0 Ma). In contrast, the evolutionary stages of the BGB are categorized into four stages: rift stage (66&amp;ndash;56 Ma), fault depression stage (40&amp;ndash;32 Ma), fault-depression transition stage (32&amp;ndash;23 Ma), and depression stage (23&amp;ndash;0 Ma). The BGB did not experience a tectonic inversion phase similar to that of the YGB, but both have undergone a fault depression stage under the same tectonic background. The rotational extrusion of the Indochina block has accelerated the opening of the rift basins along the northern and western margins of the South China Sea (SCS). The dual subduction processes of the Proto-SCS has led to the opening of the SCS Basin. Within the BGB, a significant increase in the dilatation strain rate (DSR) can be observed over a large area. The transition in the strike-slip nature of the Red River Fault Zone is evidenced by tectonic inversion in the stratigraphy. The tectonic mechanism of the YGB is primarily controlled by the convergence of the India-Eurasia plate, while the evolution of the BGB is governed by the subduction of the Pacific plate, the convergence of the India-Eurasia plate, and the dual subduction of the Proto-SCS. ]]></content:encoded> <dc:title>Reconstruction of the Cenozoic Deformation of the Yinggehai Basin and Beibu Gulf Basin, South China Sea</dc:title> <dc:creator>Jiaxiao Zhao</dc:creator> <dc:creator>Chenghao Liu</dc:creator> <dc:creator>Jingjin Zhao</dc:creator> <dc:creator>Qingjun Xu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020322</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-10</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-10</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>322</prism:startingPage> <prism:doi>10.3390/jmse13020322</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/322</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/321"> <title>JMSE, Vol. 13, Pages 321: Contemporary Issues and Advancements in Coastal Eolianite Research</title> <link>https://www.mdpi.com/2077-1312/13/2/321</link> <description>This review of eolianite research&amp;mdash;following a comprehensive overview earlier this century&amp;mdash;looks at several areas of overlapping research in coastal eolianite deposition, including the following: tectonic setting; carbonate&amp;ndash;sediment type and source areas (carbonate factories); the relationship between relative sea-level change and eolianite deposition; and the evolution of depositional models. Several locations are highlighted in order to emphasize the variety in the eolianite depositional record based on more recent research. In particular, a historical review of eolianite depositional models developed over the last 100-plus years indicates that purely high-stand models of the last century&amp;mdash;developed on steep-sided carbonate platforms&amp;mdash;do not adequately reflect the complex depositional histories found on other coastal shelves. More recent depositional models emphasize high-stand carbonate production followed by the mobilization of shelf sediments during subsequent relative drops in sea level.</description> <pubDate>2025-02-10</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 321: Contemporary Issues and Advancements in Coastal Eolianite Research Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/321">doi: 10.3390/jmse13020321</a> Authors: David H. Backus This review of eolianite research&amp;mdash;following a comprehensive overview earlier this century&amp;mdash;looks at several areas of overlapping research in coastal eolianite deposition, including the following: tectonic setting; carbonate&amp;ndash;sediment type and source areas (carbonate factories); the relationship between relative sea-level change and eolianite deposition; and the evolution of depositional models. Several locations are highlighted in order to emphasize the variety in the eolianite depositional record based on more recent research. In particular, a historical review of eolianite depositional models developed over the last 100-plus years indicates that purely high-stand models of the last century&amp;mdash;developed on steep-sided carbonate platforms&amp;mdash;do not adequately reflect the complex depositional histories found on other coastal shelves. More recent depositional models emphasize high-stand carbonate production followed by the mobilization of shelf sediments during subsequent relative drops in sea level. ]]></content:encoded> <dc:title>Contemporary Issues and Advancements in Coastal Eolianite Research</dc:title> <dc:creator>David H. Backus</dc:creator> <dc:identifier>doi: 10.3390/jmse13020321</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-10</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-10</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Review</prism:section> <prism:startingPage>321</prism:startingPage> <prism:doi>10.3390/jmse13020321</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/321</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/320"> <title>JMSE, Vol. 13, Pages 320: Hydrodynamic Circulation Modelling in the Marine Environment</title> <link>https://www.mdpi.com/2077-1312/13/2/320</link> <description>Modelling hydrodynamic circulation in the marine environment is one of the most challenging topics in the marine sciences [...]</description> <pubDate>2025-02-10</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 320: Hydrodynamic Circulation Modelling in the Marine Environment Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/320">doi: 10.3390/jmse13020320</a> Authors: Yannis Androulidakis Christos Makris Modelling hydrodynamic circulation in the marine environment is one of the most challenging topics in the marine sciences [...] ]]></content:encoded> <dc:title>Hydrodynamic Circulation Modelling in the Marine Environment</dc:title> <dc:creator>Yannis Androulidakis</dc:creator> <dc:creator>Christos Makris</dc:creator> <dc:identifier>doi: 10.3390/jmse13020320</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-10</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-10</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Editorial</prism:section> <prism:startingPage>320</prism:startingPage> <prism:doi>10.3390/jmse13020320</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/320</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/319"> <title>JMSE, Vol. 13, Pages 319: The Effects of Anthropic Structures on Coastline Morphology: A Case Study from the M&aacute;laga Coast (Spain)</title> <link>https://www.mdpi.com/2077-1312/13/2/319</link> <description>The M&amp;aacute;laga coast, in the south of Spain, is a densely populated tourist destination where ports, marinas and coastal protection structures of various typologies (e.g., groins, breakwaters, revetments) and shapes (e.g., &amp;ldquo;Y&amp;rdquo;, &amp;ldquo;L&amp;rdquo;, etc., shaped groins) have been emplaced. Such structures have modified the long- and cross-shore sediment transport and produced changes in beach morphology and the evolution of nearby areas. To characterize the changes related to shore-normal structures, beach erosion/accretion areas close to coastal anthropic structures were measured using a sequence of aerial orthophotos between 1956 and 2019, and the potential littoral sediment transport for the two main littoral transport directions was determined by means of the CMS (Coastal Modeling System). Available data on wave propagation and coastal sediment transport reflect the complex dynamics of the study area, often characterized by the coexistence of opposing longshore transport directions. Accretion was observed on both sides of ports in all studied periods and groins and groups of groins presented mixed results that reflect the heterogeneity of the study area; in certain sectors where the wave regime is bidirectional, changes in the shoreline trend were observed during the study period. The study cases described in this paper emphasize the difficulties in finding clear spatial and temporal trends in the artificially induced erosion/accretion patterns recorded along a heavily modified shoreline.</description> <pubDate>2025-02-09</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 319: The Effects of Anthropic Structures on Coastline Morphology: A Case Study from the M&aacute;laga Coast (Spain) Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/319">doi: 10.3390/jmse13020319</a> Authors: Rosa Molina Giorgio Manno Antonio Contreras de Villar Bismarck Jigena-Antelo Juan Jos茅 Mu帽oz-P茅rez J. Andrew G. Cooper Enzo Pranzini Giorgio Anfuso The M&amp;aacute;laga coast, in the south of Spain, is a densely populated tourist destination where ports, marinas and coastal protection structures of various typologies (e.g., groins, breakwaters, revetments) and shapes (e.g., &amp;ldquo;Y&amp;rdquo;, &amp;ldquo;L&amp;rdquo;, etc., shaped groins) have been emplaced. Such structures have modified the long- and cross-shore sediment transport and produced changes in beach morphology and the evolution of nearby areas. To characterize the changes related to shore-normal structures, beach erosion/accretion areas close to coastal anthropic structures were measured using a sequence of aerial orthophotos between 1956 and 2019, and the potential littoral sediment transport for the two main littoral transport directions was determined by means of the CMS (Coastal Modeling System). Available data on wave propagation and coastal sediment transport reflect the complex dynamics of the study area, often characterized by the coexistence of opposing longshore transport directions. Accretion was observed on both sides of ports in all studied periods and groins and groups of groins presented mixed results that reflect the heterogeneity of the study area; in certain sectors where the wave regime is bidirectional, changes in the shoreline trend were observed during the study period. The study cases described in this paper emphasize the difficulties in finding clear spatial and temporal trends in the artificially induced erosion/accretion patterns recorded along a heavily modified shoreline. ]]></content:encoded> <dc:title>The Effects of Anthropic Structures on Coastline Morphology: A Case Study from the M&amp;aacute;laga Coast (Spain)</dc:title> <dc:creator>Rosa Molina</dc:creator> <dc:creator>Giorgio Manno</dc:creator> <dc:creator>Antonio Contreras de Villar</dc:creator> <dc:creator>Bismarck Jigena-Antelo</dc:creator> <dc:creator>Juan Jos茅 Mu帽oz-P茅rez</dc:creator> <dc:creator>J. Andrew G. Cooper</dc:creator> <dc:creator>Enzo Pranzini</dc:creator> <dc:creator>Giorgio Anfuso</dc:creator> <dc:identifier>doi: 10.3390/jmse13020319</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-09</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-09</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>319</prism:startingPage> <prism:doi>10.3390/jmse13020319</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/319</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/318"> <title>JMSE, Vol. 13, Pages 318: Preliminary Biological Assessments of Some Algae Basis Biomaterials</title> <link>https://www.mdpi.com/2077-1312/13/2/318</link> <description>Four types of algae&amp;mdash;Porphyra umbilicalis, Undaria pinnatifida, Cystoseira barbata, and Chlorella sp.&amp;mdash;were used to obtain crude bioproducts enriched in polysaccharides (four bioproducts) and to create formulations enriched with gold cations (four bioproducts). The bioproducts obtained through aqueous extraction from Cystoseira barbata exhibited significant antioxidant activities and a total polyphenol content of (714.17 &amp;plusmn; 1.26) mg GAE/L. In the bioproducts derived from the aqueous extract of Porphyra umbilicalis and Undaria pinnatifida, combined with gold ions, gold nanoparticles with sizes of less than 34 nm were formed. In vitro tests performed on the Caco-2 tumour cell line with each of the eight bioproducts, after 24 h of exposure, showed that the crude bioproducts containing polysaccharides derived from Porphyra umbilicalis, Undaria pinnatifida, and Chlorella sp. exhibited cytotoxicity against the Caco-2 cell line. In the case of the HepG2 cell line, after 24 h of exposure, the tests indicated that only the crude polysaccharides derived from Cystoseira barbata exhibited cytotoxic effects. These results indicate the protective effect of the algal polysaccharides against the tumourigenesis processes that may occur in the human digestive system. Regarding the bioproducts containing gold, no cytotoxic effect was observed. However, in the case of the two algal bioproducts containing gold nanoparticles with a size of less than 34 nm, they may represent potential raw materials for electrochemical sensors.</description> <pubDate>2025-02-09</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 318: Preliminary Biological Assessments of Some Algae Basis Biomaterials Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/318">doi: 10.3390/jmse13020318</a> Authors: Toader Marian Nicoleta Radu Mariana Voicescu Cristina Lavinia Nistor Lucia Camelia Pirvu Mirela Mihaila Marinela Bostan Four types of algae&amp;mdash;Porphyra umbilicalis, Undaria pinnatifida, Cystoseira barbata, and Chlorella sp.&amp;mdash;were used to obtain crude bioproducts enriched in polysaccharides (four bioproducts) and to create formulations enriched with gold cations (four bioproducts). The bioproducts obtained through aqueous extraction from Cystoseira barbata exhibited significant antioxidant activities and a total polyphenol content of (714.17 &amp;plusmn; 1.26) mg GAE/L. In the bioproducts derived from the aqueous extract of Porphyra umbilicalis and Undaria pinnatifida, combined with gold ions, gold nanoparticles with sizes of less than 34 nm were formed. In vitro tests performed on the Caco-2 tumour cell line with each of the eight bioproducts, after 24 h of exposure, showed that the crude bioproducts containing polysaccharides derived from Porphyra umbilicalis, Undaria pinnatifida, and Chlorella sp. exhibited cytotoxicity against the Caco-2 cell line. In the case of the HepG2 cell line, after 24 h of exposure, the tests indicated that only the crude polysaccharides derived from Cystoseira barbata exhibited cytotoxic effects. These results indicate the protective effect of the algal polysaccharides against the tumourigenesis processes that may occur in the human digestive system. Regarding the bioproducts containing gold, no cytotoxic effect was observed. However, in the case of the two algal bioproducts containing gold nanoparticles with a size of less than 34 nm, they may represent potential raw materials for electrochemical sensors. ]]></content:encoded> <dc:title>Preliminary Biological Assessments of Some Algae Basis Biomaterials</dc:title> <dc:creator>Toader Marian</dc:creator> <dc:creator>Nicoleta Radu</dc:creator> <dc:creator>Mariana Voicescu</dc:creator> <dc:creator>Cristina Lavinia Nistor</dc:creator> <dc:creator>Lucia Camelia Pirvu</dc:creator> <dc:creator>Mirela Mihaila</dc:creator> <dc:creator>Marinela Bostan</dc:creator> <dc:identifier>doi: 10.3390/jmse13020318</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-09</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-09</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>318</prism:startingPage> <prism:doi>10.3390/jmse13020318</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/318</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/317"> <title>JMSE, Vol. 13, Pages 317: Enhanced Minimum Spanning Tree Optimization for Air-Lifted Artificial Upwelling Pipeline Network</title> <link>https://www.mdpi.com/2077-1312/13/2/317</link> <description>Artificial upwelling (AU), a geoengineering technique aimed at transporting nutrient-enriched deep-sea water to the sunlit surface layers through artificial systems, is increasingly recognized as a promising approach to enhance oceanic fertility and stimulate primary marine productivity, thereby bolstering the ocean capacity for carbon sequestration. Several air-lifted AU systems have been implemented in countries such as Norway and China. However, research on the optimization of the air injection pipeline network (AIPN)&amp;mdash;a critical component of the air-lifted AU system&amp;mdash;remains limited. This paper introduces a refined minimum spanning tree algorithm to propose a novel approach for optimizing the AIPN. Furthermore, the bubble-entrained plume loss rate (NBEP) is developed as a model to assess the efficiency of air-lifted AU systems, which is applied to three case studies involving air-lifted AU systems of varying scales. The findings indicate that the enhanced minimum spanning tree algorithm outperforms the conventional Prim&amp;rsquo;s algorithm, leading to an average 87% reduction in NBEP of the optimized AIPN, compared to the AIPN of previous air-lifted AU systems while improving system stability. Consequently, the proposed optimization method for AIPN offers valuable scientific and practical insights for the engineering design of the air-lifted AU systems across diverse scales, offering transformative potential for large-scale carbon sequestration and marine productivity enhancement.</description> <pubDate>2025-02-09</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 317: Enhanced Minimum Spanning Tree Optimization for Air-Lifted Artificial Upwelling Pipeline Network Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/317">doi: 10.3390/jmse13020317</a> Authors: Junjie Zhang Wei Fan Yonggang Zhao Zhiyu Zou Mengjie Qu Ying Chen Artificial upwelling (AU), a geoengineering technique aimed at transporting nutrient-enriched deep-sea water to the sunlit surface layers through artificial systems, is increasingly recognized as a promising approach to enhance oceanic fertility and stimulate primary marine productivity, thereby bolstering the ocean capacity for carbon sequestration. Several air-lifted AU systems have been implemented in countries such as Norway and China. However, research on the optimization of the air injection pipeline network (AIPN)&amp;mdash;a critical component of the air-lifted AU system&amp;mdash;remains limited. This paper introduces a refined minimum spanning tree algorithm to propose a novel approach for optimizing the AIPN. Furthermore, the bubble-entrained plume loss rate (NBEP) is developed as a model to assess the efficiency of air-lifted AU systems, which is applied to three case studies involving air-lifted AU systems of varying scales. The findings indicate that the enhanced minimum spanning tree algorithm outperforms the conventional Prim&amp;rsquo;s algorithm, leading to an average 87% reduction in NBEP of the optimized AIPN, compared to the AIPN of previous air-lifted AU systems while improving system stability. Consequently, the proposed optimization method for AIPN offers valuable scientific and practical insights for the engineering design of the air-lifted AU systems across diverse scales, offering transformative potential for large-scale carbon sequestration and marine productivity enhancement. ]]></content:encoded> <dc:title>Enhanced Minimum Spanning Tree Optimization for Air-Lifted Artificial Upwelling Pipeline Network</dc:title> <dc:creator>Junjie Zhang</dc:creator> <dc:creator>Wei Fan</dc:creator> <dc:creator>Yonggang Zhao</dc:creator> <dc:creator>Zhiyu Zou</dc:creator> <dc:creator>Mengjie Qu</dc:creator> <dc:creator>Ying Chen</dc:creator> <dc:identifier>doi: 10.3390/jmse13020317</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-09</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-09</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>317</prism:startingPage> <prism:doi>10.3390/jmse13020317</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/317</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/316"> <title>JMSE, Vol. 13, Pages 316: Influence of Load Variation on the Flow Field and Stability of the Francis Turbine</title> <link>https://www.mdpi.com/2077-1312/13/2/316</link> <description>With the development of a power system predominantly reliant on new energy sources, turbine generator sets are increasingly required to operate under wide load conditions, resulting in numerous unstable flow phenomena and substantial economic losses for power stations. This study employs the Shear Stress Transport (SST) k-&amp;omega; turbulence model to combine numerical simulations with experimental methods. It calculates the guide vane opening at the rated head of a Francis turbine and examines the internal flow field characteristics and pressure pulsations under various operating conditions. The findings indicate that the entropy production ratio in the draft tube is the highest among all load conditions, ranging from about 72.7% to 95.9%. Energy dissipation in the vaneless zone and the runner increases with greater opening. At 45% and 100% load conditions, the draft tube is mainly influenced by dynamic and static interference, single and double frequencies induced by runner rotation, and low-frequency fluctuations of the vortex and. Under 60% load conditions, pressure fluctuations in the draft tube are primarily caused by the eccentric vortex band, characterized by higher intensity and a frequency of 0.2 fn. Numerical results closely align with experimental observations. The findings provide essential guidance for ensuring the stable operation of power plant units.</description> <pubDate>2025-02-09</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 316: Influence of Load Variation on the Flow Field and Stability of the Francis Turbine Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/316">doi: 10.3390/jmse13020316</a> Authors: Shenhui Li Jiayang Pang Chengmei Dan Wenping Xiang Xutao Yi Xiaobing Liu With the development of a power system predominantly reliant on new energy sources, turbine generator sets are increasingly required to operate under wide load conditions, resulting in numerous unstable flow phenomena and substantial economic losses for power stations. This study employs the Shear Stress Transport (SST) k-&amp;omega; turbulence model to combine numerical simulations with experimental methods. It calculates the guide vane opening at the rated head of a Francis turbine and examines the internal flow field characteristics and pressure pulsations under various operating conditions. The findings indicate that the entropy production ratio in the draft tube is the highest among all load conditions, ranging from about 72.7% to 95.9%. Energy dissipation in the vaneless zone and the runner increases with greater opening. At 45% and 100% load conditions, the draft tube is mainly influenced by dynamic and static interference, single and double frequencies induced by runner rotation, and low-frequency fluctuations of the vortex and. Under 60% load conditions, pressure fluctuations in the draft tube are primarily caused by the eccentric vortex band, characterized by higher intensity and a frequency of 0.2 fn. Numerical results closely align with experimental observations. The findings provide essential guidance for ensuring the stable operation of power plant units. ]]></content:encoded> <dc:title>Influence of Load Variation on the Flow Field and Stability of the Francis Turbine</dc:title> <dc:creator>Shenhui Li</dc:creator> <dc:creator>Jiayang Pang</dc:creator> <dc:creator>Chengmei Dan</dc:creator> <dc:creator>Wenping Xiang</dc:creator> <dc:creator>Xutao Yi</dc:creator> <dc:creator>Xiaobing Liu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020316</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-09</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-09</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>316</prism:startingPage> <prism:doi>10.3390/jmse13020316</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/316</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/315"> <title>JMSE, Vol. 13, Pages 315: The Spatial Distribution Dynamics of Shark Bycatch by the Longline Fishery in the Western and Central Pacific Ocean</title> <link>https://www.mdpi.com/2077-1312/13/2/315</link> <description>Shark bycatch represents a substantial issue in the management of oceanic fisheries. Utilizing data on shark bycatch from the longline fishery, as released by the Western and Central Pacific Fisheries Commission, this study applied the boosted regression tree model to examine the impact of environmental factors on the bycatch per unit effort (BPUE) of key bycatch species, as well as to predict the spatial distribution dynamics of both BPUE and bycatch risk (BR). The findings emphasize that the oxygen concentration, sea surface temperature, and chlorophyll-a concentration are paramount to sharks&amp;rsquo; BPUE. Furthermore, the study compared the variations in environmental preferences across diverse shark species, pinpointing key environmental attributes defining the ecological niches of distinct shark populations. The spatial predictions identified the hotspots of BPUE and BR for the bigeye thresher shark (Alopias superciliosus), longfin mako (Isurus paucus), silky shark (Carcharhinus falciformis), and oceanic whitetip shark (Carcharhinus longimanus) in tropical latitudes (10&amp;deg; S to 15&amp;deg; N), and for the blue shark (Prionace glauca) and shortfin mako (Isurus oxyrinchus) in temperate zones (south of 30&amp;deg; S or north of 30&amp;deg; N). The geometric center analysis indicated that all shark species exhibited large annual fluctuations in BPUE and BR, and most populations displayed significant shifting trends. Several grids (5&amp;deg; &amp;times; 5&amp;deg;) were identified as high-risk areas due to their considerable contribution to bycatch. Furthermore, the geometric centers of BR were observed to shift eastward towards equatorial waters, compared to the geometric centers of BPUE. This underscores the necessity of considering factors beyond BPUE when identifying critical areas for the implementation of area-specific bycatch mitigation measures. The insights derived from this study can enhance and support the development and enforcement of targeted area-based fishery management initiatives.</description> <pubDate>2025-02-08</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 315: The Spatial Distribution Dynamics of Shark Bycatch by the Longline Fishery in the Western and Central Pacific Ocean Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/315">doi: 10.3390/jmse13020315</a> Authors: Shengyao Xia Jiaqi Wang Xiaodi Gao Yiwei Yang Heyang Huang Shark bycatch represents a substantial issue in the management of oceanic fisheries. Utilizing data on shark bycatch from the longline fishery, as released by the Western and Central Pacific Fisheries Commission, this study applied the boosted regression tree model to examine the impact of environmental factors on the bycatch per unit effort (BPUE) of key bycatch species, as well as to predict the spatial distribution dynamics of both BPUE and bycatch risk (BR). The findings emphasize that the oxygen concentration, sea surface temperature, and chlorophyll-a concentration are paramount to sharks&amp;rsquo; BPUE. Furthermore, the study compared the variations in environmental preferences across diverse shark species, pinpointing key environmental attributes defining the ecological niches of distinct shark populations. The spatial predictions identified the hotspots of BPUE and BR for the bigeye thresher shark (Alopias superciliosus), longfin mako (Isurus paucus), silky shark (Carcharhinus falciformis), and oceanic whitetip shark (Carcharhinus longimanus) in tropical latitudes (10&amp;deg; S to 15&amp;deg; N), and for the blue shark (Prionace glauca) and shortfin mako (Isurus oxyrinchus) in temperate zones (south of 30&amp;deg; S or north of 30&amp;deg; N). The geometric center analysis indicated that all shark species exhibited large annual fluctuations in BPUE and BR, and most populations displayed significant shifting trends. Several grids (5&amp;deg; &amp;times; 5&amp;deg;) were identified as high-risk areas due to their considerable contribution to bycatch. Furthermore, the geometric centers of BR were observed to shift eastward towards equatorial waters, compared to the geometric centers of BPUE. This underscores the necessity of considering factors beyond BPUE when identifying critical areas for the implementation of area-specific bycatch mitigation measures. The insights derived from this study can enhance and support the development and enforcement of targeted area-based fishery management initiatives. ]]></content:encoded> <dc:title>The Spatial Distribution Dynamics of Shark Bycatch by the Longline Fishery in the Western and Central Pacific Ocean</dc:title> <dc:creator>Shengyao Xia</dc:creator> <dc:creator>Jiaqi Wang</dc:creator> <dc:creator>Xiaodi Gao</dc:creator> <dc:creator>Yiwei Yang</dc:creator> <dc:creator>Heyang Huang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020315</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-08</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-08</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>315</prism:startingPage> <prism:doi>10.3390/jmse13020315</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/315</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/314"> <title>JMSE, Vol. 13, Pages 314: Bacterial Carbon Demand and Primary Production in a Posidonia&nbsp;oceanica System: A Re-Evaluation of Carbon Fluxes</title> <link>https://www.mdpi.com/2077-1312/13/2/314</link> <description>An earlier ecosystemic study on carbon balance calculations of a Posidonia oceanica system in the Bay of Calvi [Corsica, France], indicated that the bacterial carbon demand [BCD] between May and October [Temp &amp;gt; 18 &amp;deg;C] in the seagrass meadow could not be sustained by net leaf production of P. oceanica and its epiphytes [NPP]. Hence, the system was clearly heterotrophic as only one autotrophic region was recorded, namely the depth range from 0&amp;ndash;10 m. Already published data on the production of algal macrophytes and Cymodocea nodosa meadows and their mapping in the Bay of Calvi allowed a re-evaluation of the carbon budgets for each specific depth range. It was shown that C. nodosa could contribute significantly to covering the bacterial carbon demand of the P. oceanica system and that a positive carbon balance could be obtained for the seagrass meadow due to this carbon input when the temperature was higher than 18 &amp;deg;C, even though the depth ranges between 21&amp;ndash;30 m and 31&amp;ndash;38 m were negative. The overall trend indicates that the system cannot rely on the phytoplanktonic production of the water column, as BCD is higher than phytoplanktonic carbon production. When integrating BCD and net primary production [NPP] of the water column in summer we noticed a lack of some 97.6 to 104.3 tons of carbon which is not covered by the seagrasses leaf production and the algal macrophytes. The obtained data indicate clearly that other carbon carbon-producing compartments like the microphytobenthos, the NPP of rhizome epiphytes, and the detrital carbon import into the Bay of Calvi need to be investigated.</description> <pubDate>2025-02-08</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 314: Bacterial Carbon Demand and Primary Production in a Posidonia&nbsp;oceanica System: A Re-Evaluation of Carbon Fluxes Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/314">doi: 10.3390/jmse13020314</a> Authors: Branko Velimirov Markus Weinbauer An earlier ecosystemic study on carbon balance calculations of a Posidonia oceanica system in the Bay of Calvi [Corsica, France], indicated that the bacterial carbon demand [BCD] between May and October [Temp &amp;gt; 18 &amp;deg;C] in the seagrass meadow could not be sustained by net leaf production of P. oceanica and its epiphytes [NPP]. Hence, the system was clearly heterotrophic as only one autotrophic region was recorded, namely the depth range from 0&amp;ndash;10 m. Already published data on the production of algal macrophytes and Cymodocea nodosa meadows and their mapping in the Bay of Calvi allowed a re-evaluation of the carbon budgets for each specific depth range. It was shown that C. nodosa could contribute significantly to covering the bacterial carbon demand of the P. oceanica system and that a positive carbon balance could be obtained for the seagrass meadow due to this carbon input when the temperature was higher than 18 &amp;deg;C, even though the depth ranges between 21&amp;ndash;30 m and 31&amp;ndash;38 m were negative. The overall trend indicates that the system cannot rely on the phytoplanktonic production of the water column, as BCD is higher than phytoplanktonic carbon production. When integrating BCD and net primary production [NPP] of the water column in summer we noticed a lack of some 97.6 to 104.3 tons of carbon which is not covered by the seagrasses leaf production and the algal macrophytes. The obtained data indicate clearly that other carbon carbon-producing compartments like the microphytobenthos, the NPP of rhizome epiphytes, and the detrital carbon import into the Bay of Calvi need to be investigated. ]]></content:encoded> <dc:title>Bacterial Carbon Demand and Primary Production in a Posidonia&amp;nbsp;oceanica System: A Re-Evaluation of Carbon Fluxes</dc:title> <dc:creator>Branko Velimirov</dc:creator> <dc:creator>Markus Weinbauer</dc:creator> <dc:identifier>doi: 10.3390/jmse13020314</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-08</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-08</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>314</prism:startingPage> <prism:doi>10.3390/jmse13020314</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/314</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/313"> <title>JMSE, Vol. 13, Pages 313: A New Expression for a Goda Type Breaker Index Formula in Spectral Wave Models</title> <link>https://www.mdpi.com/2077-1312/13/2/313</link> <description>The breaker index in contemporary spectral wave models is a vital parameter in studying depth-induced wave breaking, which is an important mechanism in coastal engineering. In the previous study, the authors modified a Goda type breaker index formula and parameterized it in a spectral wave model. Although this parameterization model can accurately simulate nearshore wave height variations under various laboratory and field conditions, the computation of deep-water wave conditions in the formula necessitates reverse calculation based on the incident waves, thus limiting its applicability. To solve this problem, a new expression for this Goda type breaker index is rederived, enabling its applicability to simulate breaking waves caused by variable wave conditions on open boundaries and wind field inputs in the whole computational region. The model&amp;rsquo;s capability to simulate wave heights in laboratory and field experiments is comparable to that of the original formula.</description> <pubDate>2025-02-07</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 313: A New Expression for a Goda Type Breaker Index Formula in Spectral Wave Models Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/313">doi: 10.3390/jmse13020313</a> Authors: Zereng Chen Qinghe Zhang Yang Nie The breaker index in contemporary spectral wave models is a vital parameter in studying depth-induced wave breaking, which is an important mechanism in coastal engineering. In the previous study, the authors modified a Goda type breaker index formula and parameterized it in a spectral wave model. Although this parameterization model can accurately simulate nearshore wave height variations under various laboratory and field conditions, the computation of deep-water wave conditions in the formula necessitates reverse calculation based on the incident waves, thus limiting its applicability. To solve this problem, a new expression for this Goda type breaker index is rederived, enabling its applicability to simulate breaking waves caused by variable wave conditions on open boundaries and wind field inputs in the whole computational region. The model&amp;rsquo;s capability to simulate wave heights in laboratory and field experiments is comparable to that of the original formula. ]]></content:encoded> <dc:title>A New Expression for a Goda Type Breaker Index Formula in Spectral Wave Models</dc:title> <dc:creator>Zereng Chen</dc:creator> <dc:creator>Qinghe Zhang</dc:creator> <dc:creator>Yang Nie</dc:creator> <dc:identifier>doi: 10.3390/jmse13020313</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-07</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-07</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Technical Note</prism:section> <prism:startingPage>313</prism:startingPage> <prism:doi>10.3390/jmse13020313</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/313</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/312"> <title>JMSE, Vol. 13, Pages 312: Thresholding Dolphin Whistles Based on Signal Correlation and Impulsive Noise Features Under Stationary Wavelet Transform</title> <link>https://www.mdpi.com/2077-1312/13/2/312</link> <description>The time&amp;ndash;frequency characteristics of dolphin whistle signals under diverse ecological conditions and during environmental changes are key research topics that focus on the adaptive and response mechanisms of dolphins to the marine environment. To enhance the quality and utilization of passive acoustic monitoring (PAM) recorded dolphin whistles, the challenges faced by current wavelet thresholding methods in achieving precise threshold denoising under low signal-to-noise ratio (SNR) are confronted. This paper presents a thresholding denoising method based on stationary wavelet transform (SWT), utilizing suppression impulsive and autocorrelation function (SI-ACF) to select precise thresholds. This method introduces a denoising metric &amp;rho;, based on the correlation of whistle signals, which facilitates precise threshold estimation under low SNR without requiring prior information. Additionally, it exploits the high amplitude and broadband characteristics of impulsive noise, and utilizes the multi-resolution information of the wavelet domain to remove impulsive noise through a multi-level sliding window approach. The SI-ACF method was validated using both simulated and real whistle datasets. Simulated signals were employed to evaluate the method&amp;rsquo;s denoising performance under three types of typical underwater noise. Real whistles were used to confirm its applicability in real scenarios. The test results show the SI-ACF method effectively eliminates noise, improves whistle signal spectrogram visualization, and enhances the accuracy of automated whistle detection, highlighting its potential for whistle signal preprocessing under low SNR.</description> <pubDate>2025-02-07</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 312: Thresholding Dolphin Whistles Based on Signal Correlation and Impulsive Noise Features Under Stationary Wavelet Transform Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/312">doi: 10.3390/jmse13020312</a> Authors: Xiang Zhou Ru Wu Wen Chen Meiling Dai Peibin Zhu Xiaomei Xu The time&amp;ndash;frequency characteristics of dolphin whistle signals under diverse ecological conditions and during environmental changes are key research topics that focus on the adaptive and response mechanisms of dolphins to the marine environment. To enhance the quality and utilization of passive acoustic monitoring (PAM) recorded dolphin whistles, the challenges faced by current wavelet thresholding methods in achieving precise threshold denoising under low signal-to-noise ratio (SNR) are confronted. This paper presents a thresholding denoising method based on stationary wavelet transform (SWT), utilizing suppression impulsive and autocorrelation function (SI-ACF) to select precise thresholds. This method introduces a denoising metric &amp;rho;, based on the correlation of whistle signals, which facilitates precise threshold estimation under low SNR without requiring prior information. Additionally, it exploits the high amplitude and broadband characteristics of impulsive noise, and utilizes the multi-resolution information of the wavelet domain to remove impulsive noise through a multi-level sliding window approach. The SI-ACF method was validated using both simulated and real whistle datasets. Simulated signals were employed to evaluate the method&amp;rsquo;s denoising performance under three types of typical underwater noise. Real whistles were used to confirm its applicability in real scenarios. The test results show the SI-ACF method effectively eliminates noise, improves whistle signal spectrogram visualization, and enhances the accuracy of automated whistle detection, highlighting its potential for whistle signal preprocessing under low SNR. ]]></content:encoded> <dc:title>Thresholding Dolphin Whistles Based on Signal Correlation and Impulsive Noise Features Under Stationary Wavelet Transform</dc:title> <dc:creator>Xiang Zhou</dc:creator> <dc:creator>Ru Wu</dc:creator> <dc:creator>Wen Chen</dc:creator> <dc:creator>Meiling Dai</dc:creator> <dc:creator>Peibin Zhu</dc:creator> <dc:creator>Xiaomei Xu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020312</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-07</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-07</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>312</prism:startingPage> <prism:doi>10.3390/jmse13020312</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/312</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/311"> <title>JMSE, Vol. 13, Pages 311: Assessing the Impacts of the Israeli&ndash;Palestinian Conflict on Global Sea Transportation: From the View of Mass Tanker Trajectories</title> <link>https://www.mdpi.com/2077-1312/13/2/311</link> <description>Sea transportation plays a vital role in global trade, and studying the impact of emergencies on global sea transportation is essential to ensure the stability of trade. At present, the conflict between Palestine and Israel has attracted extensive attention worldwide. However, there is a lack of specific research on the impact of conflict on shipping, particularly on global shipping costs. By using the global vessel trajectory data of tankers from the Automatic Identification System (AIS) and taking the global sea transportation of large tankers as an example, this paper quantifies and visualizes the changes in global sea transportation before and after conflicts from a data-driven perspective. Firstly, the complete vessel trajectory, as well as the port of departure and the port of destination are extracted. Then, from the perspective of shipping cost and vessel traffic flow, we evaluate the vessel traffic flow changes caused by the conflict by using the route distance to replace the shipping costs and quantify the cost increase for the relevant countries caused by the vessel detour based on the shipping cost increment index. The research results show that after the outbreak of the conflict, the number of vessels passing through the Red Sea area has decreased significantly. About 3.1% of global vessels were affected, with global sea transportation costs of large tankers increasing by about 0.0825%. This study takes the Israeli&amp;ndash;Palestinian conflict as an example and analyzes the impact of emergencies on the global sea transportation situation of tankers based on AIS data. The research results reveal the characteristics of international shipping to a certain extent and provide guidance for global sea transportation route planning.</description> <pubDate>2025-02-07</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 311: Assessing the Impacts of the Israeli&ndash;Palestinian Conflict on Global Sea Transportation: From the View of Mass Tanker Trajectories Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/311">doi: 10.3390/jmse13020311</a> Authors: Bing Zhang Xiaohui Chen Haiyan Liu Lin Ye Ran Zhang Yunpeng Zhao Sea transportation plays a vital role in global trade, and studying the impact of emergencies on global sea transportation is essential to ensure the stability of trade. At present, the conflict between Palestine and Israel has attracted extensive attention worldwide. However, there is a lack of specific research on the impact of conflict on shipping, particularly on global shipping costs. By using the global vessel trajectory data of tankers from the Automatic Identification System (AIS) and taking the global sea transportation of large tankers as an example, this paper quantifies and visualizes the changes in global sea transportation before and after conflicts from a data-driven perspective. Firstly, the complete vessel trajectory, as well as the port of departure and the port of destination are extracted. Then, from the perspective of shipping cost and vessel traffic flow, we evaluate the vessel traffic flow changes caused by the conflict by using the route distance to replace the shipping costs and quantify the cost increase for the relevant countries caused by the vessel detour based on the shipping cost increment index. The research results show that after the outbreak of the conflict, the number of vessels passing through the Red Sea area has decreased significantly. About 3.1% of global vessels were affected, with global sea transportation costs of large tankers increasing by about 0.0825%. This study takes the Israeli&amp;ndash;Palestinian conflict as an example and analyzes the impact of emergencies on the global sea transportation situation of tankers based on AIS data. The research results reveal the characteristics of international shipping to a certain extent and provide guidance for global sea transportation route planning. ]]></content:encoded> <dc:title>Assessing the Impacts of the Israeli&amp;ndash;Palestinian Conflict on Global Sea Transportation: From the View of Mass Tanker Trajectories</dc:title> <dc:creator>Bing Zhang</dc:creator> <dc:creator>Xiaohui Chen</dc:creator> <dc:creator>Haiyan Liu</dc:creator> <dc:creator>Lin Ye</dc:creator> <dc:creator>Ran Zhang</dc:creator> <dc:creator>Yunpeng Zhao</dc:creator> <dc:identifier>doi: 10.3390/jmse13020311</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-07</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-07</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>311</prism:startingPage> <prism:doi>10.3390/jmse13020311</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/311</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/310"> <title>JMSE, Vol. 13, Pages 310: Hydrodynamics Model Identification and Model-Based Control Application of a New Type of AUV</title> <link>https://www.mdpi.com/2077-1312/13/2/310</link> <description>The hydrodynamic coefficients of underwater robots can be used to evaluate their maneuverability and motion stability and to design motion controllers, thereby reducing experimental time and costs. In this paper, an Autonomous Underwater Vehicle (AUV) with a negative-lift profile is designed. The spatially constrained motion method, combined with neural networks, is utilized to identify all the hydrodynamic coefficients in the standard hydrodynamic equations of the AUV. Subsequently, based on the goodness-of-fit, the significance of the hydrodynamic coefficients is evaluated to yield a simplified hydrodynamic equation. Given the cost constraints, it was not feasible to obtain precise experimental data on hydrodynamic coefficients to validate the accuracy of the CFD calculation method. Therefore, the hydrodynamic coefficients were used to construct a dynamic model for the AUV, and an MPC controller was designed based on this model. Finally, simulations and pool tests were conducted on the AUV, and a comparative analysis of the simulation results with the pool test results revealed that although there were certain errors in the calculation of the hydrodynamic coefficients, the controller constructed within this margin of error was still capable of effectively controlling the AUV. This fully demonstrates the feasibility and applicability of using CFD methods to calculate hydrodynamic coefficients and establishing model predictive control methods based on these coefficients in practical applications.</description> <pubDate>2025-02-07</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 310: Hydrodynamics Model Identification and Model-Based Control Application of a New Type of AUV Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/310">doi: 10.3390/jmse13020310</a> Authors: Lunyang Lin Yuxiang Chen Hong Xiong Chunliang Yu Hong Zhu Yiyang Xing Guodong Zheng The hydrodynamic coefficients of underwater robots can be used to evaluate their maneuverability and motion stability and to design motion controllers, thereby reducing experimental time and costs. In this paper, an Autonomous Underwater Vehicle (AUV) with a negative-lift profile is designed. The spatially constrained motion method, combined with neural networks, is utilized to identify all the hydrodynamic coefficients in the standard hydrodynamic equations of the AUV. Subsequently, based on the goodness-of-fit, the significance of the hydrodynamic coefficients is evaluated to yield a simplified hydrodynamic equation. Given the cost constraints, it was not feasible to obtain precise experimental data on hydrodynamic coefficients to validate the accuracy of the CFD calculation method. Therefore, the hydrodynamic coefficients were used to construct a dynamic model for the AUV, and an MPC controller was designed based on this model. Finally, simulations and pool tests were conducted on the AUV, and a comparative analysis of the simulation results with the pool test results revealed that although there were certain errors in the calculation of the hydrodynamic coefficients, the controller constructed within this margin of error was still capable of effectively controlling the AUV. This fully demonstrates the feasibility and applicability of using CFD methods to calculate hydrodynamic coefficients and establishing model predictive control methods based on these coefficients in practical applications. ]]></content:encoded> <dc:title>Hydrodynamics Model Identification and Model-Based Control Application of a New Type of AUV</dc:title> <dc:creator>Lunyang Lin</dc:creator> <dc:creator>Yuxiang Chen</dc:creator> <dc:creator>Hong Xiong</dc:creator> <dc:creator>Chunliang Yu</dc:creator> <dc:creator>Hong Zhu</dc:creator> <dc:creator>Yiyang Xing</dc:creator> <dc:creator>Guodong Zheng</dc:creator> <dc:identifier>doi: 10.3390/jmse13020310</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-07</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-07</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>310</prism:startingPage> <prism:doi>10.3390/jmse13020310</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/310</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/309"> <title>JMSE, Vol. 13, Pages 309: Artificial Fish Reef Site Evaluation Based on Multi-Source High-Resolution Acoustic Images</title> <link>https://www.mdpi.com/2077-1312/13/2/309</link> <description>Marine geophysical and geological investigations are crucial for evaluating the construction suitability of artificial fish reefs (AFRs). Key factors such as seabed topography, geomorphology, sub-bottom structure, and sediment type significantly influence AFR design and site selection. Challenges such as material sinking, sediment instability, and scouring effects should be critically considered and addressed in the construction of AFR, particularly in areas with soft mud or dynamic environments. In this study, detailed investigations were conducted approximately seven months after the deployment of reef materials in the AFR experimental zones around Xiaoguan Island, located in the western South Yellow Sea, China. Based on morphological factors, using data from multibeam echosounders and side-scan sonar, the study area was divided into three geomorphic zones, namely, the tidal flat (TF), underwater erosion-accumulation slope (UEABS), and inclined erosion-accumulation shelf plain (IEASP) zones. The focus of this study was on the UEABS and IEASP experimental zones, where reef materials (concrete or stone blocks) were deployed seven months earlier. The comprehensive interpretation results of multi-source high-resolution acoustic images showed that the average settlement of individual reefs in the UEABS experimental zone was 0.49 m, and their surrounding seabed experienced little to no scouring. This suggested the formation of an effective range and height, making the zone suitable for AFR construction. However, in the IEASP experimental zone, the seabed sediment consisted of soft mud, causing the reef materials to sink into the seabed after deployment, preventing the formation of an effective range and height, and rendering the area unsuitable for AFR construction. These findings provided valuable scientific guidance for AFR construction in the study area and other similar coastal regions.</description> <pubDate>2025-02-07</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 309: Artificial Fish Reef Site Evaluation Based on Multi-Source High-Resolution Acoustic Images Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/309">doi: 10.3390/jmse13020309</a> Authors: Fangqi Wang Yikai Feng Senbo Liu Yilan Chen Jisheng Ding Marine geophysical and geological investigations are crucial for evaluating the construction suitability of artificial fish reefs (AFRs). Key factors such as seabed topography, geomorphology, sub-bottom structure, and sediment type significantly influence AFR design and site selection. Challenges such as material sinking, sediment instability, and scouring effects should be critically considered and addressed in the construction of AFR, particularly in areas with soft mud or dynamic environments. In this study, detailed investigations were conducted approximately seven months after the deployment of reef materials in the AFR experimental zones around Xiaoguan Island, located in the western South Yellow Sea, China. Based on morphological factors, using data from multibeam echosounders and side-scan sonar, the study area was divided into three geomorphic zones, namely, the tidal flat (TF), underwater erosion-accumulation slope (UEABS), and inclined erosion-accumulation shelf plain (IEASP) zones. The focus of this study was on the UEABS and IEASP experimental zones, where reef materials (concrete or stone blocks) were deployed seven months earlier. The comprehensive interpretation results of multi-source high-resolution acoustic images showed that the average settlement of individual reefs in the UEABS experimental zone was 0.49 m, and their surrounding seabed experienced little to no scouring. This suggested the formation of an effective range and height, making the zone suitable for AFR construction. However, in the IEASP experimental zone, the seabed sediment consisted of soft mud, causing the reef materials to sink into the seabed after deployment, preventing the formation of an effective range and height, and rendering the area unsuitable for AFR construction. These findings provided valuable scientific guidance for AFR construction in the study area and other similar coastal regions. ]]></content:encoded> <dc:title>Artificial Fish Reef Site Evaluation Based on Multi-Source High-Resolution Acoustic Images</dc:title> <dc:creator>Fangqi Wang</dc:creator> <dc:creator>Yikai Feng</dc:creator> <dc:creator>Senbo Liu</dc:creator> <dc:creator>Yilan Chen</dc:creator> <dc:creator>Jisheng Ding</dc:creator> <dc:identifier>doi: 10.3390/jmse13020309</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-07</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-07</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>309</prism:startingPage> <prism:doi>10.3390/jmse13020309</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/309</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/308"> <title>JMSE, Vol. 13, Pages 308: Submarine Slides and Their Influence on Gas Hydrate and Shallow Gas in the Pearl River Mouth Basin</title> <link>https://www.mdpi.com/2077-1312/13/2/308</link> <description>Submarine slides, gas hydrates, shallow gas, and volcanoes considered to be potential geohazards have been well delineated using three-dimensional (3D) seismic data and well log data in the Pearl River Mouth Basin, South China Sea. Seismic characteristics, distribution maps, and controlling factors of these geohazards have been well analyzed showing the influence of regional tectonics and sedimentary processes. Recently, shallow gas and gas hydrates are confirmed by drilling expeditions, which are considered important unconventional resources. Moreover, the mapped features of various geohazards show the spatial overlays and that they are connected each other. To delineate well the relationships between gas hydrates, shallow gas, and the potential geological features such as submarine slides, gas chimneys, faults, and volcanoes, the seismic attributes and interpretations are displayed using 3D seismic data to show the interplay between them. Gas hydrates and shallow gas occur and are widely distributed above sills, volcanoes, gas chimneys, and faults within the submarine slides and migrating canyon because large amount of hydrocarbon gas can migrate from the deep layer to the shallow layer along different pathways. This study aims to show the correlation among various geological bodies and their effects on shallow gas and gas hydrate distributions.</description> <pubDate>2025-02-07</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 308: Submarine Slides and Their Influence on Gas Hydrate and Shallow Gas in the Pearl River Mouth Basin Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/308">doi: 10.3390/jmse13020308</a> Authors: Jiapeng Jin Jinzi Hu Lixia Li Jie Li Zhenyu Zhu Xiujuan Wang Jilin Zhou Wenlong Wang Submarine slides, gas hydrates, shallow gas, and volcanoes considered to be potential geohazards have been well delineated using three-dimensional (3D) seismic data and well log data in the Pearl River Mouth Basin, South China Sea. Seismic characteristics, distribution maps, and controlling factors of these geohazards have been well analyzed showing the influence of regional tectonics and sedimentary processes. Recently, shallow gas and gas hydrates are confirmed by drilling expeditions, which are considered important unconventional resources. Moreover, the mapped features of various geohazards show the spatial overlays and that they are connected each other. To delineate well the relationships between gas hydrates, shallow gas, and the potential geological features such as submarine slides, gas chimneys, faults, and volcanoes, the seismic attributes and interpretations are displayed using 3D seismic data to show the interplay between them. Gas hydrates and shallow gas occur and are widely distributed above sills, volcanoes, gas chimneys, and faults within the submarine slides and migrating canyon because large amount of hydrocarbon gas can migrate from the deep layer to the shallow layer along different pathways. This study aims to show the correlation among various geological bodies and their effects on shallow gas and gas hydrate distributions. ]]></content:encoded> <dc:title>Submarine Slides and Their Influence on Gas Hydrate and Shallow Gas in the Pearl River Mouth Basin</dc:title> <dc:creator>Jiapeng Jin</dc:creator> <dc:creator>Jinzi Hu</dc:creator> <dc:creator>Lixia Li</dc:creator> <dc:creator>Jie Li</dc:creator> <dc:creator>Zhenyu Zhu</dc:creator> <dc:creator>Xiujuan Wang</dc:creator> <dc:creator>Jilin Zhou</dc:creator> <dc:creator>Wenlong Wang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020308</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-07</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-07</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>308</prism:startingPage> <prism:doi>10.3390/jmse13020308</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/308</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/307"> <title>JMSE, Vol. 13, Pages 307: Time-Domain Simulation of Coupled Motions for Five Fishing Vessels Moored Side-by-Side in a Harbor</title> <link>https://www.mdpi.com/2077-1312/13/2/307</link> <description>With the rapid development and accelerated utilization of marine resources, multi-body floating systems have become extensively used in practical applications. This study examines the coupled motions of a side-by-side anchoring system for five fishing vessels in a harbor using ANSYS-AQWA. The system is connected by hawsers and equipped with fenders to reduce collisions between the vessels. It is designed to operate in the sheltered wind-wave combined environment within Ningbo Zhoushan Port, China. Considering the diverse types and quantities of fishing vessels in the anchorage area, this paper proposes a mixed arrangement of three large-scale fishing vessels in the middle and two small-scale vessels on both sides. The time-domain analysis is performed on this system under the combined effects of wind and waves, calculating the motion responses of the five fishing vessels along with the mechanical loads at the hawsers, fenders, and moorings. The results indicate that the maximum loads on these mechanical components remain well within the safe working limits, ensuring reliable operation. In addition, the impact of varying wind-wave angles on the coupled motions of the fishing vessel system are studied. As the wind-wave angle increases, the surge motion of the fishing vessels gradually decreases, while the sway motion intensifies. The forces on the hawsers, fenders, and mooring system exhibit distinct characteristics at different angles.</description> <pubDate>2025-02-07</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 307: Time-Domain Simulation of Coupled Motions for Five Fishing Vessels Moored Side-by-Side in a Harbor Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/307">doi: 10.3390/jmse13020307</a> Authors: Xuran Men Jinlong He Bo Jiao Guibing Zhu Haihua Lin Hongyuan Sun With the rapid development and accelerated utilization of marine resources, multi-body floating systems have become extensively used in practical applications. This study examines the coupled motions of a side-by-side anchoring system for five fishing vessels in a harbor using ANSYS-AQWA. The system is connected by hawsers and equipped with fenders to reduce collisions between the vessels. It is designed to operate in the sheltered wind-wave combined environment within Ningbo Zhoushan Port, China. Considering the diverse types and quantities of fishing vessels in the anchorage area, this paper proposes a mixed arrangement of three large-scale fishing vessels in the middle and two small-scale vessels on both sides. The time-domain analysis is performed on this system under the combined effects of wind and waves, calculating the motion responses of the five fishing vessels along with the mechanical loads at the hawsers, fenders, and moorings. The results indicate that the maximum loads on these mechanical components remain well within the safe working limits, ensuring reliable operation. In addition, the impact of varying wind-wave angles on the coupled motions of the fishing vessel system are studied. As the wind-wave angle increases, the surge motion of the fishing vessels gradually decreases, while the sway motion intensifies. The forces on the hawsers, fenders, and mooring system exhibit distinct characteristics at different angles. ]]></content:encoded> <dc:title>Time-Domain Simulation of Coupled Motions for Five Fishing Vessels Moored Side-by-Side in a Harbor</dc:title> <dc:creator>Xuran Men</dc:creator> <dc:creator>Jinlong He</dc:creator> <dc:creator>Bo Jiao</dc:creator> <dc:creator>Guibing Zhu</dc:creator> <dc:creator>Haihua Lin</dc:creator> <dc:creator>Hongyuan Sun</dc:creator> <dc:identifier>doi: 10.3390/jmse13020307</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-07</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-07</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>307</prism:startingPage> <prism:doi>10.3390/jmse13020307</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/307</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/306"> <title>JMSE, Vol. 13, Pages 306: Underwater Target Localization Method Based on Uniform Linear Electrode Array</title> <link>https://www.mdpi.com/2077-1312/13/2/306</link> <description>The underwater electric field signal can be excited by underwater vehicles, such as the shaft-rate electric field and the corrosion electric field. The electric field signature of each vehicle exhibits significant differences in time and frequency domain, which can be exploited to determine target positions. In this paper, a novel passive localization method for underwater targets is presented, leveraging a uniform linear electrode array (ULEA). The ULEA manifold along the axial direction is derived from the electric field propagation in an infinite lossy medium, which provides the nonlinear mapping relationship between the target position and the voltage data acquired by the ULEA. In order to locate the targets, the multiple signal classification (MUSIC) algorithm is applied. Then, capitalizing on the rotational invariance of matrix operations and exploiting the symmetry inherent in the ULEA, we streamline the six-dimensional spatial spectral scanning onto a two-dimensional plane, providing azimuth and distance information for the targets. This method significantly reduces computational overhead. To validate the efficacy of our proposed method, we devise a localization system and conduct a simulation environment to estimate targets. Results show that our method achieves satisfactory direction and reliable distance estimations, even in scenarios with low signal-to-noise ratios.</description> <pubDate>2025-02-06</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 306: Underwater Target Localization Method Based on Uniform Linear Electrode Array Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/306">doi: 10.3390/jmse13020306</a> Authors: Wenjing Shang Feixiang Gao Jiahui Liu Yunhe Pang Sergey V. Volvenko Vladimir M. Olshanskiy Yidong Xu The underwater electric field signal can be excited by underwater vehicles, such as the shaft-rate electric field and the corrosion electric field. The electric field signature of each vehicle exhibits significant differences in time and frequency domain, which can be exploited to determine target positions. In this paper, a novel passive localization method for underwater targets is presented, leveraging a uniform linear electrode array (ULEA). The ULEA manifold along the axial direction is derived from the electric field propagation in an infinite lossy medium, which provides the nonlinear mapping relationship between the target position and the voltage data acquired by the ULEA. In order to locate the targets, the multiple signal classification (MUSIC) algorithm is applied. Then, capitalizing on the rotational invariance of matrix operations and exploiting the symmetry inherent in the ULEA, we streamline the six-dimensional spatial spectral scanning onto a two-dimensional plane, providing azimuth and distance information for the targets. This method significantly reduces computational overhead. To validate the efficacy of our proposed method, we devise a localization system and conduct a simulation environment to estimate targets. Results show that our method achieves satisfactory direction and reliable distance estimations, even in scenarios with low signal-to-noise ratios. ]]></content:encoded> <dc:title>Underwater Target Localization Method Based on Uniform Linear Electrode Array</dc:title> <dc:creator>Wenjing Shang</dc:creator> <dc:creator>Feixiang Gao</dc:creator> <dc:creator>Jiahui Liu</dc:creator> <dc:creator>Yunhe Pang</dc:creator> <dc:creator>Sergey V. Volvenko</dc:creator> <dc:creator>Vladimir M. Olshanskiy</dc:creator> <dc:creator>Yidong Xu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020306</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-06</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-06</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>306</prism:startingPage> <prism:doi>10.3390/jmse13020306</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/306</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/305"> <title>JMSE, Vol. 13, Pages 305: Comparative Analysis of the Alternative Energy: Case of Reducing GHG Emissions of Estonian Pilot Fleet</title> <link>https://www.mdpi.com/2077-1312/13/2/305</link> <description>The FuelEU Maritime Regulation, part of the European Union&amp;rsquo;s (EU&amp;rsquo;s) Fit for 55 initiative, aims to achieve significant reductions in greenhouse gas (GHG) emissions within the maritime sector. This study assesses the feasibility of alternative fuels for the Estonian pilot fleet using a Well-to-Wake (WtW) life cycle assessment (LCA) methodology. Operational data from 18 vessels, sourced from the Estonian State Fleet&amp;rsquo;s records, were analyzed, including technical specifications, fuel consumption patterns, and operational scenarios. The study focused on marine diesel oil (MDO), biomethane, hydrogen, biodiesel, ammonia, and hydrotreated vegetable oil (HVO), each presenting distinct trade-offs. Biomethane achieved a 59% GHG emissions reduction but required a volumetric storage capacity up to 353% higher compared to MDO. Biodiesel reduced GHG emissions by 41.2%, offering moderate compatibility with existing systems while requiring up to 23% larger storage volumes. HVO demonstrated a 43.6% emissions reduction with seamless integration into existing marine engines. Ammonia showed strong potential for long-term decarbonization, but its adoption is hindered by low energy density and complex storage requirements. This research underscores the importance of a holistic evaluation of alternative fuels, taking into account technical, economic, and environmental factors specific to regional and operational contexts. The findings offer a quantitative basis for policymakers and maritime stakeholders to develop effective decarbonization strategies for the Baltic Sea region.</description> <pubDate>2025-02-06</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 305: Comparative Analysis of the Alternative Energy: Case of Reducing GHG Emissions of Estonian Pilot Fleet Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/305">doi: 10.3390/jmse13020305</a> Authors: Riina Otsason Andres Laasma Yi千it G眉lmez Jonne Kotta Ulla Tapaninen The FuelEU Maritime Regulation, part of the European Union&amp;rsquo;s (EU&amp;rsquo;s) Fit for 55 initiative, aims to achieve significant reductions in greenhouse gas (GHG) emissions within the maritime sector. This study assesses the feasibility of alternative fuels for the Estonian pilot fleet using a Well-to-Wake (WtW) life cycle assessment (LCA) methodology. Operational data from 18 vessels, sourced from the Estonian State Fleet&amp;rsquo;s records, were analyzed, including technical specifications, fuel consumption patterns, and operational scenarios. The study focused on marine diesel oil (MDO), biomethane, hydrogen, biodiesel, ammonia, and hydrotreated vegetable oil (HVO), each presenting distinct trade-offs. Biomethane achieved a 59% GHG emissions reduction but required a volumetric storage capacity up to 353% higher compared to MDO. Biodiesel reduced GHG emissions by 41.2%, offering moderate compatibility with existing systems while requiring up to 23% larger storage volumes. HVO demonstrated a 43.6% emissions reduction with seamless integration into existing marine engines. Ammonia showed strong potential for long-term decarbonization, but its adoption is hindered by low energy density and complex storage requirements. This research underscores the importance of a holistic evaluation of alternative fuels, taking into account technical, economic, and environmental factors specific to regional and operational contexts. The findings offer a quantitative basis for policymakers and maritime stakeholders to develop effective decarbonization strategies for the Baltic Sea region. ]]></content:encoded> <dc:title>Comparative Analysis of the Alternative Energy: Case of Reducing GHG Emissions of Estonian Pilot Fleet</dc:title> <dc:creator>Riina Otsason</dc:creator> <dc:creator>Andres Laasma</dc:creator> <dc:creator>Yi千it G眉lmez</dc:creator> <dc:creator>Jonne Kotta</dc:creator> <dc:creator>Ulla Tapaninen</dc:creator> <dc:identifier>doi: 10.3390/jmse13020305</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-06</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-06</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>305</prism:startingPage> <prism:doi>10.3390/jmse13020305</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/305</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/304"> <title>JMSE, Vol. 13, Pages 304: Preliminary Investigation of the Spatial-Temporal Characteristics and Vertical Dynamics of Internal Solitary Waves in the South China Sea from SWOT Data</title> <link>https://www.mdpi.com/2077-1312/13/2/304</link> <description>Internal waves are crucial for understanding oceanographic parameters such as spatiotemporal distribution and energy transfer. They significantly impact ocean circulation, marine ecosystems, and offshore operations. However, studying internal waves is challenging due to their dynamic nature and the need for effective observation methods. This study investigated nonlinear internal solitary waves (ISWs) in the South China Sea using SSHa data from the SWOT satellite mission (Cycles 2 to 20). The distribution patterns and seasonal variations in ISWs were analyzed, revealing that ISWs are more frequently observed in summer while being rarely detected in winter. By combining SSHa observations with a Mode-1 vertical structure model, the isopycnal displacement, velocity fields, and energy characteristics of ISWs were reconstructed. The results show a maximum isopycnal displacement of 160 m at 400 m depth and peak kinetic energy near the surface (~2000 J/m3) and potential energy at a depth of around 300 m (~9000 J/m3). These findings highlight the vertical variability of ISWs and demonstrate the capability of SWOT data in capturing their fine-scale evolution, providing new opportunities for oceanic research and enhancing our understanding of internal waves&amp;rsquo; impact on marine environments and ocean circulation.</description> <pubDate>2025-02-06</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 304: Preliminary Investigation of the Spatial-Temporal Characteristics and Vertical Dynamics of Internal Solitary Waves in the South China Sea from SWOT Data Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/304">doi: 10.3390/jmse13020304</a> Authors: Zhikuan Pan Zhenhe Zhai Qi Li Qianqian Li Lin Wu Lifeng Bao Internal waves are crucial for understanding oceanographic parameters such as spatiotemporal distribution and energy transfer. They significantly impact ocean circulation, marine ecosystems, and offshore operations. However, studying internal waves is challenging due to their dynamic nature and the need for effective observation methods. This study investigated nonlinear internal solitary waves (ISWs) in the South China Sea using SSHa data from the SWOT satellite mission (Cycles 2 to 20). The distribution patterns and seasonal variations in ISWs were analyzed, revealing that ISWs are more frequently observed in summer while being rarely detected in winter. By combining SSHa observations with a Mode-1 vertical structure model, the isopycnal displacement, velocity fields, and energy characteristics of ISWs were reconstructed. The results show a maximum isopycnal displacement of 160 m at 400 m depth and peak kinetic energy near the surface (~2000 J/m3) and potential energy at a depth of around 300 m (~9000 J/m3). These findings highlight the vertical variability of ISWs and demonstrate the capability of SWOT data in capturing their fine-scale evolution, providing new opportunities for oceanic research and enhancing our understanding of internal waves&amp;rsquo; impact on marine environments and ocean circulation. ]]></content:encoded> <dc:title>Preliminary Investigation of the Spatial-Temporal Characteristics and Vertical Dynamics of Internal Solitary Waves in the South China Sea from SWOT Data</dc:title> <dc:creator>Zhikuan Pan</dc:creator> <dc:creator>Zhenhe Zhai</dc:creator> <dc:creator>Qi Li</dc:creator> <dc:creator>Qianqian Li</dc:creator> <dc:creator>Lin Wu</dc:creator> <dc:creator>Lifeng Bao</dc:creator> <dc:identifier>doi: 10.3390/jmse13020304</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-06</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-06</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>304</prism:startingPage> <prism:doi>10.3390/jmse13020304</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/304</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/303"> <title>JMSE, Vol. 13, Pages 303: Integrated Navigation Algorithm for Autonomous Underwater Vehicle Based on Linear Kalman Filter, Thrust Model, and Propeller Tachometer</title> <link>https://www.mdpi.com/2077-1312/13/2/303</link> <description>For the purpose of reducing the cost, size, and weight of the integrated navigation system of an AUV (autonomous underwater vehicle), and improving the stealth of this system, an integrated navigation algorithm based on a propeller tachometer is proposed. The algorithm consists of five steps: &amp;#9312; establishing the resistance model of AUV, &amp;#9313; establishing the thrust model, &amp;#9314; utilizing the measured speeds obtained from the AUV&amp;rsquo;s voyage trials for calibration, &amp;#9315; discrimination and replacement of outliers from the tachometer measurements, and &amp;#9316; establishing a linear Kalman filter (LKF) with water currents as state variables. This paper provides the modeling procedure, formula derivations, model parameters, and algorithm process, etc. Through research and analysis, the proposed algorithm&amp;rsquo;s accuracy has been improved. The specific values of the localization error are detailed in the main text. Therefore, the proposed algorithm has high accuracy, a strong anti-interference capability, and good robustness. Moreover, it exhibits certain adaptability to complex environments and value for practical engineering.</description> <pubDate>2025-02-06</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 303: Integrated Navigation Algorithm for Autonomous Underwater Vehicle Based on Linear Kalman Filter, Thrust Model, and Propeller Tachometer Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/303">doi: 10.3390/jmse13020303</a> Authors: Haosu Zhang Yueying Cai Jin Yue Wei Mu Shiyin Zhou Defei Jin Lingji Xu For the purpose of reducing the cost, size, and weight of the integrated navigation system of an AUV (autonomous underwater vehicle), and improving the stealth of this system, an integrated navigation algorithm based on a propeller tachometer is proposed. The algorithm consists of five steps: &amp;#9312; establishing the resistance model of AUV, &amp;#9313; establishing the thrust model, &amp;#9314; utilizing the measured speeds obtained from the AUV&amp;rsquo;s voyage trials for calibration, &amp;#9315; discrimination and replacement of outliers from the tachometer measurements, and &amp;#9316; establishing a linear Kalman filter (LKF) with water currents as state variables. This paper provides the modeling procedure, formula derivations, model parameters, and algorithm process, etc. Through research and analysis, the proposed algorithm&amp;rsquo;s accuracy has been improved. The specific values of the localization error are detailed in the main text. Therefore, the proposed algorithm has high accuracy, a strong anti-interference capability, and good robustness. Moreover, it exhibits certain adaptability to complex environments and value for practical engineering. ]]></content:encoded> <dc:title>Integrated Navigation Algorithm for Autonomous Underwater Vehicle Based on Linear Kalman Filter, Thrust Model, and Propeller Tachometer</dc:title> <dc:creator>Haosu Zhang</dc:creator> <dc:creator>Yueying Cai</dc:creator> <dc:creator>Jin Yue</dc:creator> <dc:creator>Wei Mu</dc:creator> <dc:creator>Shiyin Zhou</dc:creator> <dc:creator>Defei Jin</dc:creator> <dc:creator>Lingji Xu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020303</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-06</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-06</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>303</prism:startingPage> <prism:doi>10.3390/jmse13020303</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/303</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/302"> <title>JMSE, Vol. 13, Pages 302: A Low-Power Consumption Deepwater Subsea Electric Gate Valve Actuator, Part A: Prototype and Test</title> <link>https://www.mdpi.com/2077-1312/13/2/302</link> <description>All-electric systems represent the current development trend in subsea control systems, and the subsea electric gate valve actuator is the core equipment item in all-electric subsea control systems. To solve the problems of the traditional subsea electric gate valve actuator with low safety, poor reliability, and high energy consumption, in this paper, a new subsea electric gate valve actuator configuration concept is proposed, where the actuator has a redundant drive, a low-power holding function, a fail-safe shutdown mechanism, an emergency operation capability, and other functions. An actuator prototype was developed, an actuator integration test system was constructed, and the prototype actuator was combined with a standard subsea gate valve, an all-electric subsea control module, and other equipment to conduct several functional tests. The test results show that the actuator functions and performance indicators meet the designed requirements. Compared with the existing actuators, in addition to high reliability and safety, the driving power consumption can be reduced by 5% and holding power consumption can be reduced by 40%.</description> <pubDate>2025-02-06</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 302: A Low-Power Consumption Deepwater Subsea Electric Gate Valve Actuator, Part A: Prototype and Test Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/302">doi: 10.3390/jmse13020302</a> Authors: Wenlong Zhang Peng Jia Huailiang Zheng Gang Wang Tao Wang Xiangyu Wang Feihong Yun Mengxuan Wu All-electric systems represent the current development trend in subsea control systems, and the subsea electric gate valve actuator is the core equipment item in all-electric subsea control systems. To solve the problems of the traditional subsea electric gate valve actuator with low safety, poor reliability, and high energy consumption, in this paper, a new subsea electric gate valve actuator configuration concept is proposed, where the actuator has a redundant drive, a low-power holding function, a fail-safe shutdown mechanism, an emergency operation capability, and other functions. An actuator prototype was developed, an actuator integration test system was constructed, and the prototype actuator was combined with a standard subsea gate valve, an all-electric subsea control module, and other equipment to conduct several functional tests. The test results show that the actuator functions and performance indicators meet the designed requirements. Compared with the existing actuators, in addition to high reliability and safety, the driving power consumption can be reduced by 5% and holding power consumption can be reduced by 40%. ]]></content:encoded> <dc:title>A Low-Power Consumption Deepwater Subsea Electric Gate Valve Actuator, Part A: Prototype and Test</dc:title> <dc:creator>Wenlong Zhang</dc:creator> <dc:creator>Peng Jia</dc:creator> <dc:creator>Huailiang Zheng</dc:creator> <dc:creator>Gang Wang</dc:creator> <dc:creator>Tao Wang</dc:creator> <dc:creator>Xiangyu Wang</dc:creator> <dc:creator>Feihong Yun</dc:creator> <dc:creator>Mengxuan Wu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020302</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-06</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-06</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>302</prism:startingPage> <prism:doi>10.3390/jmse13020302</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/302</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/301"> <title>JMSE, Vol. 13, Pages 301: Shallow Gas Distribution Influenced by the Interface of Sedimentary Facies in the Southwest of the Qiongdongnan Basin</title> <link>https://www.mdpi.com/2077-1312/13/2/301</link> <description>Shallow gas, with huge resources, has been confirmed using three dimensional (3D) seismic data and more than 20 drilling sites in the deep water of the LS36 gas field, the Qiongdongnan Basin, the South China Sea. The interface of sedimentary facies in the southern boundary of the basin controls the distribution within the basin of clastic sediments coming from the north and west of the land uplifted. In this study, seismic data and geophysical attributes were used to investigate the controlling effect of the interface of sedimentary facies on the distribution of shallow gas within the basin. Our study shows that the shallow gas is mainly distributed in the Quaternary Ledong Formation in the southwest of the Qiongdongnan Basin, which was observed from acoustic impedance, amplitude versus offset (AVO), and seismic interpretations. The channelized submarine fans that onlap the interface of the sedimentary facies are distributed in a vertically stacked manner and are the main reservoirs for the shallow gas. Therefore, these sedimentary studies show that the sand-rich sediments are distributed along the interface of the sedimentary facies from the southwest to the northeast and are limited to the shallow gas within the basin. The Central Canyon provides an important deep gas source, while the flank of the canyon, gas chimney, and normal faults related to basement uplift provide pathways for vertical and lateral gas migration to form the shallow gas. This study shows that shallow gas may be widely distributed in other marginal sea basins, and sedimentary systems should be further studied in the future.</description> <pubDate>2025-02-06</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 301: Shallow Gas Distribution Influenced by the Interface of Sedimentary Facies in the Southwest of the Qiongdongnan Basin Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/301">doi: 10.3390/jmse13020301</a> Authors: Taotao Yang Xiaohan Li Jiapeng Jin Jianwei Chen Zhi Gong Li Zhao Wenlong Wang Bo Liu Jinzi Hu Wenlu Wang Xiujuan Wang Shallow gas, with huge resources, has been confirmed using three dimensional (3D) seismic data and more than 20 drilling sites in the deep water of the LS36 gas field, the Qiongdongnan Basin, the South China Sea. The interface of sedimentary facies in the southern boundary of the basin controls the distribution within the basin of clastic sediments coming from the north and west of the land uplifted. In this study, seismic data and geophysical attributes were used to investigate the controlling effect of the interface of sedimentary facies on the distribution of shallow gas within the basin. Our study shows that the shallow gas is mainly distributed in the Quaternary Ledong Formation in the southwest of the Qiongdongnan Basin, which was observed from acoustic impedance, amplitude versus offset (AVO), and seismic interpretations. The channelized submarine fans that onlap the interface of the sedimentary facies are distributed in a vertically stacked manner and are the main reservoirs for the shallow gas. Therefore, these sedimentary studies show that the sand-rich sediments are distributed along the interface of the sedimentary facies from the southwest to the northeast and are limited to the shallow gas within the basin. The Central Canyon provides an important deep gas source, while the flank of the canyon, gas chimney, and normal faults related to basement uplift provide pathways for vertical and lateral gas migration to form the shallow gas. This study shows that shallow gas may be widely distributed in other marginal sea basins, and sedimentary systems should be further studied in the future. ]]></content:encoded> <dc:title>Shallow Gas Distribution Influenced by the Interface of Sedimentary Facies in the Southwest of the Qiongdongnan Basin</dc:title> <dc:creator>Taotao Yang</dc:creator> <dc:creator>Xiaohan Li</dc:creator> <dc:creator>Jiapeng Jin</dc:creator> <dc:creator>Jianwei Chen</dc:creator> <dc:creator>Zhi Gong</dc:creator> <dc:creator>Li Zhao</dc:creator> <dc:creator>Wenlong Wang</dc:creator> <dc:creator>Bo Liu</dc:creator> <dc:creator>Jinzi Hu</dc:creator> <dc:creator>Wenlu Wang</dc:creator> <dc:creator>Xiujuan Wang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020301</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-06</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-06</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>301</prism:startingPage> <prism:doi>10.3390/jmse13020301</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/301</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/299"> <title>JMSE, Vol. 13, Pages 299: Quantitative Assessment of Vessel Traffic Service Center Workload: Development and Validation of the Vessel Traffic Service Operator Workload Index (VOWI)</title> <link>https://www.mdpi.com/2077-1312/13/2/299</link> <description>This study addresses the critical challenge of lacking quantitative measures for objective evaluation of vessel traffic service (VTS) operator workload, where current uniform staffing approaches fail to reflect center-specific operational characteristics. The VTS Operator Workload Index (VOWI) model was developed using the Delphi&amp;ndash;AHP methodology to determine the relative importance of key factors including traffic, sea area characteristics, port facilities, and weather conditions, which formed the basis for calculating both center-wide and per-operator workload indices. Factor analysis revealed that traffic factors showed the highest importance at 0.4627, followed by sea area (0.1960), port facilities (0.1916), and weather (0.1497) factors. Application of the VOWI model to 19 VTS centers in South Korea demonstrated that per-operator workload at Busan, Incheon, and Ulsan VTS was up to three times higher than at other centers. This finding indicates that the current uniform staffing approach based on sector count inadequately reflects each center&amp;rsquo;s actual operational characteristics. The VOWI model provides objective criteria for efficient personnel management in VTS centers and is expected to contribute to improving VTS service quality.</description> <pubDate>2025-02-06</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 299: Quantitative Assessment of Vessel Traffic Service Center Workload: Development and Validation of the Vessel Traffic Service Operator Workload Index (VOWI) Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/299">doi: 10.3390/jmse13020299</a> Authors: Gil-Ho Shin Chae-Uk Song Daewon Kim This study addresses the critical challenge of lacking quantitative measures for objective evaluation of vessel traffic service (VTS) operator workload, where current uniform staffing approaches fail to reflect center-specific operational characteristics. The VTS Operator Workload Index (VOWI) model was developed using the Delphi&amp;ndash;AHP methodology to determine the relative importance of key factors including traffic, sea area characteristics, port facilities, and weather conditions, which formed the basis for calculating both center-wide and per-operator workload indices. Factor analysis revealed that traffic factors showed the highest importance at 0.4627, followed by sea area (0.1960), port facilities (0.1916), and weather (0.1497) factors. Application of the VOWI model to 19 VTS centers in South Korea demonstrated that per-operator workload at Busan, Incheon, and Ulsan VTS was up to three times higher than at other centers. This finding indicates that the current uniform staffing approach based on sector count inadequately reflects each center&amp;rsquo;s actual operational characteristics. The VOWI model provides objective criteria for efficient personnel management in VTS centers and is expected to contribute to improving VTS service quality. ]]></content:encoded> <dc:title>Quantitative Assessment of Vessel Traffic Service Center Workload: Development and Validation of the Vessel Traffic Service Operator Workload Index (VOWI)</dc:title> <dc:creator>Gil-Ho Shin</dc:creator> <dc:creator>Chae-Uk Song</dc:creator> <dc:creator>Daewon Kim</dc:creator> <dc:identifier>doi: 10.3390/jmse13020299</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-06</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-06</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>299</prism:startingPage> <prism:doi>10.3390/jmse13020299</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/299</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/300"> <title>JMSE, Vol. 13, Pages 300: Water Depth Correction-Based Classification Combination Method for Extracting Shallow Sea Reef Geomorphological Information: A Case Study of Xisha Chau and Zhaoshu Island</title> <link>https://www.mdpi.com/2077-1312/13/2/300</link> <description>Remote sensing monitoring and geomorphologic change analysis of coral reefs are of great practical significance for the ecological protection and sustainable development of coral reef area resources. A WBMD scheme is proposed to better extract coral reef information from island environments of Xisha, China. Satellite imagery, after preprocessing, is subjected to water depth correction to mitigate the influence of water depth on reflectance. A maximum likelihood classification model is then used for geomorphological classification, followed by refinement through a decision tree classification model, forming the WBMD scheme. The overall accuracy of geomorphological classification for Xisha Chau and Zhaoshu Island based on the WBMD scheme was 97.07% and 95.07%. Using this scheme to analyze the geomorphology of Xisha Chau and Zhaoshu Island from 2014 to 2018 reveals that the degradation of coral reef on Xisha Chau is mainly distributed in the lagoon slope and around the lagoon, and the lagoon area on Zhaoshu Island has been shrinking year by year, while the area of the gray sand island has increased, and the areas of other geomorphological types exhibit fluctuating changes. Previous studies on coral reefs have indicated that coral reefs are mainly distributed in the lagoon slope area, where significant coral reef degradation has also been observed, raising an alarm for coral reef conservation efforts in China.</description> <pubDate>2025-02-06</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 300: Water Depth Correction-Based Classification Combination Method for Extracting Shallow Sea Reef Geomorphological Information: A Case Study of Xisha Chau and Zhaoshu Island Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/300">doi: 10.3390/jmse13020300</a> Authors: Zhigang Lu Weidong Zhu Daxing Lei Yi Zhu Yifan Chen Zilin Yue Zhongqiang Wu Remote sensing monitoring and geomorphologic change analysis of coral reefs are of great practical significance for the ecological protection and sustainable development of coral reef area resources. A WBMD scheme is proposed to better extract coral reef information from island environments of Xisha, China. Satellite imagery, after preprocessing, is subjected to water depth correction to mitigate the influence of water depth on reflectance. A maximum likelihood classification model is then used for geomorphological classification, followed by refinement through a decision tree classification model, forming the WBMD scheme. The overall accuracy of geomorphological classification for Xisha Chau and Zhaoshu Island based on the WBMD scheme was 97.07% and 95.07%. Using this scheme to analyze the geomorphology of Xisha Chau and Zhaoshu Island from 2014 to 2018 reveals that the degradation of coral reef on Xisha Chau is mainly distributed in the lagoon slope and around the lagoon, and the lagoon area on Zhaoshu Island has been shrinking year by year, while the area of the gray sand island has increased, and the areas of other geomorphological types exhibit fluctuating changes. Previous studies on coral reefs have indicated that coral reefs are mainly distributed in the lagoon slope area, where significant coral reef degradation has also been observed, raising an alarm for coral reef conservation efforts in China. ]]></content:encoded> <dc:title>Water Depth Correction-Based Classification Combination Method for Extracting Shallow Sea Reef Geomorphological Information: A Case Study of Xisha Chau and Zhaoshu Island</dc:title> <dc:creator>Zhigang Lu</dc:creator> <dc:creator>Weidong Zhu</dc:creator> <dc:creator>Daxing Lei</dc:creator> <dc:creator>Yi Zhu</dc:creator> <dc:creator>Yifan Chen</dc:creator> <dc:creator>Zilin Yue</dc:creator> <dc:creator>Zhongqiang Wu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020300</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-06</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-06</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>300</prism:startingPage> <prism:doi>10.3390/jmse13020300</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/300</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/298"> <title>JMSE, Vol. 13, Pages 298: Storm Surge Clusters, Multi-Peak Storms and Their Effect on the Performance of the Maeslant Storm Surge Barrier (The Netherlands)</title> <link>https://www.mdpi.com/2077-1312/13/2/298</link> <description>Storm surge barriers are crucial for the flood protection of the Netherlands and other deltas. In the Netherlands, the reliability of flood defenses is typically assessed based on extreme water levels and wave height statistics. Yet, in the case of operated flood defenses, such as storm surge barriers, the temporal clustering of successive events may be just as important. This study investigates the evolution and associated flood risk of clusters of successive storm tide peaks at the Maeslant Storm Surge Barrier in the Netherlands. Two mechanisms are considered. Multi-peak storm surge events, as a consequence of tidal movement on top of the surge, are studied by means of stochastic storm tide events. Clusters of storm tides resulting from different, but related storms are investigated by means of time series analysis of a long sea-level record. We conclude that the tendency of extreme storm tide peaks to cluster is especially related to the seasonality in storm activity. In the current situation, the occurrence of clusters of storm tide peaks have only a minor influence of the flood risk in the area behind the Maeslant Storm Surge Barrier. We envision, however, that this influence is likely to increase with sea-level rise. The numbers are, however, uncertain due to the strong sensitivity to assumptions, model choices and the applied data set. More insight into the statistics of the time evolution of extreme sea water levels is needed to better understand and ultimately to reduce these uncertainties.</description> <pubDate>2025-02-06</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 298: Storm Surge Clusters, Multi-Peak Storms and Their Effect on the Performance of the Maeslant Storm Surge Barrier (The Netherlands) Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/298">doi: 10.3390/jmse13020298</a> Authors: Alexander M. R. Bakker Dion L. T. Rovers Leslie F. Mooyaart Storm surge barriers are crucial for the flood protection of the Netherlands and other deltas. In the Netherlands, the reliability of flood defenses is typically assessed based on extreme water levels and wave height statistics. Yet, in the case of operated flood defenses, such as storm surge barriers, the temporal clustering of successive events may be just as important. This study investigates the evolution and associated flood risk of clusters of successive storm tide peaks at the Maeslant Storm Surge Barrier in the Netherlands. Two mechanisms are considered. Multi-peak storm surge events, as a consequence of tidal movement on top of the surge, are studied by means of stochastic storm tide events. Clusters of storm tides resulting from different, but related storms are investigated by means of time series analysis of a long sea-level record. We conclude that the tendency of extreme storm tide peaks to cluster is especially related to the seasonality in storm activity. In the current situation, the occurrence of clusters of storm tide peaks have only a minor influence of the flood risk in the area behind the Maeslant Storm Surge Barrier. We envision, however, that this influence is likely to increase with sea-level rise. The numbers are, however, uncertain due to the strong sensitivity to assumptions, model choices and the applied data set. More insight into the statistics of the time evolution of extreme sea water levels is needed to better understand and ultimately to reduce these uncertainties. ]]></content:encoded> <dc:title>Storm Surge Clusters, Multi-Peak Storms and Their Effect on the Performance of the Maeslant Storm Surge Barrier (The Netherlands)</dc:title> <dc:creator>Alexander M. R. Bakker</dc:creator> <dc:creator>Dion L. T. Rovers</dc:creator> <dc:creator>Leslie F. Mooyaart</dc:creator> <dc:identifier>doi: 10.3390/jmse13020298</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-06</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-06</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>298</prism:startingPage> <prism:doi>10.3390/jmse13020298</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/298</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/297"> <title>JMSE, Vol. 13, Pages 297: Research on Water-Entry Hydrodynamics for a Cross-Wing Underwater Vehicle</title> <link>https://www.mdpi.com/2077-1312/13/2/297</link> <description>The optimization of the water-entry strategy for cross-wing underwater vehicles has become a research hotspot in the field of engineering, and its water-entry process is quite different from that of wedges and cylinders. In order to address this problem, a water-entry numerical model for the cross-wing underwater vehicle was first established based on the CFD method. The governing equations and boundary conditions of the dynamic model were defined, along with the basic principles of discretization and turbulent flow of the governing equations. The overset mesh and the VOF multiphase flow model were introduced, and a mesh size independence analysis of the numerical model was conducted. Furthermore, the numerical results were compared with the experimental results to ensure the accuracy of the numerical model. The research focused on the cross-wing underwater vehicle&amp;rsquo;s impact with calm water and regular waves, respectively. The results show that: (1) the numerical simulations are in good agreement with the experimental results (the maximum predictive error is less than 10%), which verifies the accuracy of the numerical model in this paper; (2) when the cross-wing underwater vehicle impacts calm water, the slamming pressure curve firstly shows a trend of increasing, reaching a peak, and then decreasing sharply, and finally stabilizes. As the water-entry velocity increases, the peak slamming pressure exhibits a gradual increase; (3) during the water entry of the cross-wing underwater vehicle into calm water, the acceleration profile demonstrates a trend of initial increase, followed by a decrease, another increase, and then a subsequent decrease as the entry velocity continues to rise. It should be noted that there are two peaks in the acceleration, with the first peak being significantly smaller than that of the second; (4) when the cross-wing underwater vehicle impacts a regular wave, the slamming pressure is lowest when impacting the crest and highest when impacting the trough.</description> <pubDate>2025-02-05</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 297: Research on Water-Entry Hydrodynamics for a Cross-Wing Underwater Vehicle Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/297">doi: 10.3390/jmse13020297</a> Authors: Yunsai Chen Haozhen Pang Dong Zhang Zhang Shi Qinghua Jiang The optimization of the water-entry strategy for cross-wing underwater vehicles has become a research hotspot in the field of engineering, and its water-entry process is quite different from that of wedges and cylinders. In order to address this problem, a water-entry numerical model for the cross-wing underwater vehicle was first established based on the CFD method. The governing equations and boundary conditions of the dynamic model were defined, along with the basic principles of discretization and turbulent flow of the governing equations. The overset mesh and the VOF multiphase flow model were introduced, and a mesh size independence analysis of the numerical model was conducted. Furthermore, the numerical results were compared with the experimental results to ensure the accuracy of the numerical model. The research focused on the cross-wing underwater vehicle&amp;rsquo;s impact with calm water and regular waves, respectively. The results show that: (1) the numerical simulations are in good agreement with the experimental results (the maximum predictive error is less than 10%), which verifies the accuracy of the numerical model in this paper; (2) when the cross-wing underwater vehicle impacts calm water, the slamming pressure curve firstly shows a trend of increasing, reaching a peak, and then decreasing sharply, and finally stabilizes. As the water-entry velocity increases, the peak slamming pressure exhibits a gradual increase; (3) during the water entry of the cross-wing underwater vehicle into calm water, the acceleration profile demonstrates a trend of initial increase, followed by a decrease, another increase, and then a subsequent decrease as the entry velocity continues to rise. It should be noted that there are two peaks in the acceleration, with the first peak being significantly smaller than that of the second; (4) when the cross-wing underwater vehicle impacts a regular wave, the slamming pressure is lowest when impacting the crest and highest when impacting the trough. ]]></content:encoded> <dc:title>Research on Water-Entry Hydrodynamics for a Cross-Wing Underwater Vehicle</dc:title> <dc:creator>Yunsai Chen</dc:creator> <dc:creator>Haozhen Pang</dc:creator> <dc:creator>Dong Zhang</dc:creator> <dc:creator>Zhang Shi</dc:creator> <dc:creator>Qinghua Jiang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020297</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-05</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-05</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>297</prism:startingPage> <prism:doi>10.3390/jmse13020297</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/297</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/296"> <title>JMSE, Vol. 13, Pages 296: RUL Prediction for Lithium Battery Systems in Fuel Cell Ships Based on Adaptive Modal Enhancement Networks</title> <link>https://www.mdpi.com/2077-1312/13/2/296</link> <description>With the widespread application of fuel cell technology in the fields of transportation and energy, Battery Management Systems (BMSs) have become one of the key technologies for ensuring system stability and extending battery lifespan. As an auxiliary power source in fuel cell systems, the prediction of the Remaining Useful Life (RUL) of lithium-ion batteries is crucial for enhancing the reliability and efficiency of fuel cell ships. However, due to the complex degradation mechanisms of lithium batteries and the actual noisy operating conditions, particularly capacity regeneration noise, accurate RUL prediction remains a challenge. To address this issue, this paper proposes a lithium battery RUL prediction method based on an Adaptive Modal Enhancement Network (RIME-VMD-SEInformer). By incorporating an improved Variational Mode Decomposition (VMD) technique, the RIME algorithm is used to optimize decomposition parameters for the adaptive extraction of key modes from the signal. The Squeeze-and-Excitation Networks (SEAttention) module is employed to enhance the accuracy of feature extraction, and the sparse attention mechanism of Informer is utilized to efficiently model long-term dependencies in time series. This results in a comprehensive prediction framework that spans signal decomposition, feature enhancement, and time-series modeling. The method is validated on several public datasets, and the results demonstrate that each component of the RIME-VMD-SEInformer framework is both necessary and justifiable, leading to improved performance. The model outperforms the state-of-the-art models, with a MAPE of only 0.00837 on the B0005 dataset, representing a 59.96% reduction compared to other algorithms, showcasing outstanding prediction performance.</description> <pubDate>2025-02-05</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 296: RUL Prediction for Lithium Battery Systems in Fuel Cell Ships Based on Adaptive Modal Enhancement Networks Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/296">doi: 10.3390/jmse13020296</a> Authors: Yifan Liu Huabiao Jin Xiangguo Yang Telu Tang Jiaxin Luo Lei Han Junting Lang Weixin Zhao With the widespread application of fuel cell technology in the fields of transportation and energy, Battery Management Systems (BMSs) have become one of the key technologies for ensuring system stability and extending battery lifespan. As an auxiliary power source in fuel cell systems, the prediction of the Remaining Useful Life (RUL) of lithium-ion batteries is crucial for enhancing the reliability and efficiency of fuel cell ships. However, due to the complex degradation mechanisms of lithium batteries and the actual noisy operating conditions, particularly capacity regeneration noise, accurate RUL prediction remains a challenge. To address this issue, this paper proposes a lithium battery RUL prediction method based on an Adaptive Modal Enhancement Network (RIME-VMD-SEInformer). By incorporating an improved Variational Mode Decomposition (VMD) technique, the RIME algorithm is used to optimize decomposition parameters for the adaptive extraction of key modes from the signal. The Squeeze-and-Excitation Networks (SEAttention) module is employed to enhance the accuracy of feature extraction, and the sparse attention mechanism of Informer is utilized to efficiently model long-term dependencies in time series. This results in a comprehensive prediction framework that spans signal decomposition, feature enhancement, and time-series modeling. The method is validated on several public datasets, and the results demonstrate that each component of the RIME-VMD-SEInformer framework is both necessary and justifiable, leading to improved performance. The model outperforms the state-of-the-art models, with a MAPE of only 0.00837 on the B0005 dataset, representing a 59.96% reduction compared to other algorithms, showcasing outstanding prediction performance. ]]></content:encoded> <dc:title>RUL Prediction for Lithium Battery Systems in Fuel Cell Ships Based on Adaptive Modal Enhancement Networks</dc:title> <dc:creator>Yifan Liu</dc:creator> <dc:creator>Huabiao Jin</dc:creator> <dc:creator>Xiangguo Yang</dc:creator> <dc:creator>Telu Tang</dc:creator> <dc:creator>Jiaxin Luo</dc:creator> <dc:creator>Lei Han</dc:creator> <dc:creator>Junting Lang</dc:creator> <dc:creator>Weixin Zhao</dc:creator> <dc:identifier>doi: 10.3390/jmse13020296</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-05</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-05</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>296</prism:startingPage> <prism:doi>10.3390/jmse13020296</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/296</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/295"> <title>JMSE, Vol. 13, Pages 295: A Two-Decade Overview of the Environmental Carrying Capacity in Bah&iacute;a Santa Maria&ndash;La Reforma Coastal Lagoon System</title> <link>https://www.mdpi.com/2077-1312/13/2/295</link> <description>Santa Mar&amp;iacute;a Bay&amp;ndash;La Reforma (SMBLR), with its 58,300 ha is one of Mexico&amp;rsquo;s most extensive estuarine lagoon systems. It is made up of islands, estuaries, and mangrove areas, which provide a vital part of the habitat and refuge of a significant number of birds, fish, amphibians, reptiles, and mammals. The fishing of blue and brown shrimp, marine and estuarine fish, as well as the exploitation of crab and bivalve mollusks, represent an important economic value for the communities that live there and for the state of Sinaloa, Mexico. This state ranked second in fisheries production and first in aquaculture production by 2023. However, the biological richness of this ecosystem has historically been threatened by economic activities such as agriculture, livestock, and aquaculture that, via watersheds, translate into continuous inputs of nutrients and other pollutants. This has led to modifications to the system such as changes in the structure of pelagic and benthic communities, mainly in response to eutrophication. To understand the dynamics of nutrient inputs to the ecosystem, this work presents a comparative analysis of the system&amp;rsquo;s carrying capacity and the magnitude of the main economic activities from 2007 to 2019. We found that during each season of the year and its transitions, the system functions as a nitrogen and phosphorus sink, which is associated with autotrophic net ecosystem metabolism and nitrogen fixation processes. We suggest that while water residence times in SMBLR are short, these are strongly influenced by the high volumes of water and nutrient loads determined by the spatio-temporal variations in hydrological drainage from the basins of influence of the system. The discharge of agriculture and aquaculture drains into SMBLR are areas of concern due to the high amount of nutrients. Although SMBLR is mostly an autotrophic system, there are signs that the carrying capacity during some seasons has been exceeded, and adverse ecological and socioeconomic effects in the basin are evident.</description> <pubDate>2025-02-05</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 295: A Two-Decade Overview of the Environmental Carrying Capacity in Bah&iacute;a Santa Maria&ndash;La Reforma Coastal Lagoon System Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/295">doi: 10.3390/jmse13020295</a> Authors: Omar Calvario-Mart铆nez Julio Medina-Galvan Virginia P. Dom铆nguez-Jim茅nez Rosalba Alonso-Rodr铆guez Miguel A. S谩nchez-Rodr铆guez Paulina M. Reyes-Velarde Miguel Betancourt-Lozano David Serrano-Hern谩ndez Santa Mar&amp;iacute;a Bay&amp;ndash;La Reforma (SMBLR), with its 58,300 ha is one of Mexico&amp;rsquo;s most extensive estuarine lagoon systems. It is made up of islands, estuaries, and mangrove areas, which provide a vital part of the habitat and refuge of a significant number of birds, fish, amphibians, reptiles, and mammals. The fishing of blue and brown shrimp, marine and estuarine fish, as well as the exploitation of crab and bivalve mollusks, represent an important economic value for the communities that live there and for the state of Sinaloa, Mexico. This state ranked second in fisheries production and first in aquaculture production by 2023. However, the biological richness of this ecosystem has historically been threatened by economic activities such as agriculture, livestock, and aquaculture that, via watersheds, translate into continuous inputs of nutrients and other pollutants. This has led to modifications to the system such as changes in the structure of pelagic and benthic communities, mainly in response to eutrophication. To understand the dynamics of nutrient inputs to the ecosystem, this work presents a comparative analysis of the system&amp;rsquo;s carrying capacity and the magnitude of the main economic activities from 2007 to 2019. We found that during each season of the year and its transitions, the system functions as a nitrogen and phosphorus sink, which is associated with autotrophic net ecosystem metabolism and nitrogen fixation processes. We suggest that while water residence times in SMBLR are short, these are strongly influenced by the high volumes of water and nutrient loads determined by the spatio-temporal variations in hydrological drainage from the basins of influence of the system. The discharge of agriculture and aquaculture drains into SMBLR are areas of concern due to the high amount of nutrients. Although SMBLR is mostly an autotrophic system, there are signs that the carrying capacity during some seasons has been exceeded, and adverse ecological and socioeconomic effects in the basin are evident. ]]></content:encoded> <dc:title>A Two-Decade Overview of the Environmental Carrying Capacity in Bah&amp;iacute;a Santa Maria&amp;ndash;La Reforma Coastal Lagoon System</dc:title> <dc:creator>Omar Calvario-Mart铆nez</dc:creator> <dc:creator>Julio Medina-Galvan</dc:creator> <dc:creator>Virginia P. Dom铆nguez-Jim茅nez</dc:creator> <dc:creator>Rosalba Alonso-Rodr铆guez</dc:creator> <dc:creator>Miguel A. S谩nchez-Rodr铆guez</dc:creator> <dc:creator>Paulina M. Reyes-Velarde</dc:creator> <dc:creator>Miguel Betancourt-Lozano</dc:creator> <dc:creator>David Serrano-Hern谩ndez</dc:creator> <dc:identifier>doi: 10.3390/jmse13020295</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-05</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-05</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>295</prism:startingPage> <prism:doi>10.3390/jmse13020295</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/295</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/294"> <title>JMSE, Vol. 13, Pages 294: Development and Operation of a Free-Fall Type Glass Sphere Underwater Observation System with Suspended Cable in the Seto Inland Sea</title> <link>https://www.mdpi.com/2077-1312/13/2/294</link> <description>We have developed a free-fall type glass sphere underwater observation system with suspended cable. The developed observation system is quite simple to construct and is able to operate at deep sea because the system is structured by glass sphere. The glass sphere has high endurability. Due to no motion system like thrusters, the position of a free-fall type underwater observation system is not clear. And hence, we propose the operation of a free-fall type underwater observation system with a suspended cable like a zipline. To make the position of the system more precise, an inertial measurement unit (IMU) is installed inside the system. A router is also installed inside the system to obtain underwater pictures via a LAN cable. The observation system, which is named UWOS (Under Water Observation System), was operated in the Seto Inland Sea. It was found that the UWOS indicates the possibility of a free-fall type glass sphere underwater observation system with a suspended cable.</description> <pubDate>2025-02-05</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 294: Development and Operation of a Free-Fall Type Glass Sphere Underwater Observation System with Suspended Cable in the Seto Inland Sea Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/294">doi: 10.3390/jmse13020294</a> Authors: Taisei Atsumi Yuki Shin Takumi Ishiyama Masaki Furuya Yousuke Hayashi Yoshikazu Koike We have developed a free-fall type glass sphere underwater observation system with suspended cable. The developed observation system is quite simple to construct and is able to operate at deep sea because the system is structured by glass sphere. The glass sphere has high endurability. Due to no motion system like thrusters, the position of a free-fall type underwater observation system is not clear. And hence, we propose the operation of a free-fall type underwater observation system with a suspended cable like a zipline. To make the position of the system more precise, an inertial measurement unit (IMU) is installed inside the system. A router is also installed inside the system to obtain underwater pictures via a LAN cable. The observation system, which is named UWOS (Under Water Observation System), was operated in the Seto Inland Sea. It was found that the UWOS indicates the possibility of a free-fall type glass sphere underwater observation system with a suspended cable. ]]></content:encoded> <dc:title>Development and Operation of a Free-Fall Type Glass Sphere Underwater Observation System with Suspended Cable in the Seto Inland Sea</dc:title> <dc:creator>Taisei Atsumi</dc:creator> <dc:creator>Yuki Shin</dc:creator> <dc:creator>Takumi Ishiyama</dc:creator> <dc:creator>Masaki Furuya</dc:creator> <dc:creator>Yousuke Hayashi</dc:creator> <dc:creator>Yoshikazu Koike</dc:creator> <dc:identifier>doi: 10.3390/jmse13020294</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-05</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-05</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>294</prism:startingPage> <prism:doi>10.3390/jmse13020294</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/294</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/293"> <title>JMSE, Vol. 13, Pages 293: Contact and Non-Contact Measurements of Chlorophyll-a in Water Based on Laser Spectroscopy</title> <link>https://www.mdpi.com/2077-1312/13/2/293</link> <description>Chlorophyll-a fluorescence detection is an important technique for monitoring water quality. In this paper, we proposed an approach that employs the ratio of fluorescence to Raman obtained from contact and non-contact laser-induced fluorescence detection methods as the key for the detection of Chlorophyll-a in water. At first, extracted Chlorophyll-a solutions were prepared, and each sample was tested using two detection methods. The true values of the samples were measured in the laboratory using spectrophotometry. Then, the detection system was calibrated through the linear fitting of Chlorophyll-a and the fluorescence&amp;ndash;Raman ratio. The linear correlation coefficients of contact and non-contact detection were 0.9453 and 0.9401, respectively. Finally, we tested the actual water samples in two ways, and compared the test results with the value measured using the national standard method. The root mean square error (RMSE) of contact and non-contact detection was 0.16 and 0.23, respectively. The results show that the two detection methods have high accuracy and sensitivity, and preliminary preparation of samples is not required. Compared with contact detection, the non-contact detection results had higher accuracy and stronger anti-interference, but the maintenance cost was higher because the probe is vulnerable to wear. The advantage of non-contact detection is that it avoids sample contamination and is easy to apply over large areas of water. In the future, it can be used for the real-time monitoring of algal biomass in water by selecting the appropriate detection method according to the requirements of the application.</description> <pubDate>2025-02-04</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 293: Contact and Non-Contact Measurements of Chlorophyll-a in Water Based on Laser Spectroscopy Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/293">doi: 10.3390/jmse13020293</a> Authors: Xiuyue Dong Xiaohua Che Zhaoshuo Tian Chlorophyll-a fluorescence detection is an important technique for monitoring water quality. In this paper, we proposed an approach that employs the ratio of fluorescence to Raman obtained from contact and non-contact laser-induced fluorescence detection methods as the key for the detection of Chlorophyll-a in water. At first, extracted Chlorophyll-a solutions were prepared, and each sample was tested using two detection methods. The true values of the samples were measured in the laboratory using spectrophotometry. Then, the detection system was calibrated through the linear fitting of Chlorophyll-a and the fluorescence&amp;ndash;Raman ratio. The linear correlation coefficients of contact and non-contact detection were 0.9453 and 0.9401, respectively. Finally, we tested the actual water samples in two ways, and compared the test results with the value measured using the national standard method. The root mean square error (RMSE) of contact and non-contact detection was 0.16 and 0.23, respectively. The results show that the two detection methods have high accuracy and sensitivity, and preliminary preparation of samples is not required. Compared with contact detection, the non-contact detection results had higher accuracy and stronger anti-interference, but the maintenance cost was higher because the probe is vulnerable to wear. The advantage of non-contact detection is that it avoids sample contamination and is easy to apply over large areas of water. In the future, it can be used for the real-time monitoring of algal biomass in water by selecting the appropriate detection method according to the requirements of the application. ]]></content:encoded> <dc:title>Contact and Non-Contact Measurements of Chlorophyll-a in Water Based on Laser Spectroscopy</dc:title> <dc:creator>Xiuyue Dong</dc:creator> <dc:creator>Xiaohua Che</dc:creator> <dc:creator>Zhaoshuo Tian</dc:creator> <dc:identifier>doi: 10.3390/jmse13020293</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-04</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-04</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>293</prism:startingPage> <prism:doi>10.3390/jmse13020293</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/293</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/292"> <title>JMSE, Vol. 13, Pages 292: Remote Sensing Tools for Monitoring Marine Phanerogams: A Review of Sentinel and Landsat Applications</title> <link>https://www.mdpi.com/2077-1312/13/2/292</link> <description>Seagrasses play a pivotal role in maintaining marine ecosystems, supporting biodiversity, and preventing sediment loss during storms. Their capacity for photosynthesis and growth is linked to light availability in the continental shelf waters. Satellite platforms such as Landsat (USGS) and Sentinel (ESA) provide accessible imagery for the monitoring of these submerged plants. This study employed the PRISMA methodology to conduct a systematic review of the literature, with the objective of identifying articles focused on these seagrasses and their detection via satellite imagery. The identified methodologies included the use of vegetation and water indices, which were validated through empirical observations, as well as supervised classification algorithms, such as Random Forest, Maximum Likelihood, and Support Vector Machine. These approaches were applied to Mediterranean and other coastal regions, revealing changes in seagrass cover due to anchor damage in tourist areas and trawling scars that resemble plough marks. Such tools are vital for informing management actions, such as the implementation of restrictions on anchoring and bottom trawling, in order to protect these vulnerable ecosystems. By enabling targeted interventions, this approach facilitates the preservation of seagrass meadows, which are also critical for carbon sequestration and the sustainability of marine habitats.</description> <pubDate>2025-02-04</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 292: Remote Sensing Tools for Monitoring Marine Phanerogams: A Review of Sentinel and Landsat Applications Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/292">doi: 10.3390/jmse13020292</a> Authors: Noelia Campillo-Tamarit Juan V铆ctor Molner Juan M. Soria Seagrasses play a pivotal role in maintaining marine ecosystems, supporting biodiversity, and preventing sediment loss during storms. Their capacity for photosynthesis and growth is linked to light availability in the continental shelf waters. Satellite platforms such as Landsat (USGS) and Sentinel (ESA) provide accessible imagery for the monitoring of these submerged plants. This study employed the PRISMA methodology to conduct a systematic review of the literature, with the objective of identifying articles focused on these seagrasses and their detection via satellite imagery. The identified methodologies included the use of vegetation and water indices, which were validated through empirical observations, as well as supervised classification algorithms, such as Random Forest, Maximum Likelihood, and Support Vector Machine. These approaches were applied to Mediterranean and other coastal regions, revealing changes in seagrass cover due to anchor damage in tourist areas and trawling scars that resemble plough marks. Such tools are vital for informing management actions, such as the implementation of restrictions on anchoring and bottom trawling, in order to protect these vulnerable ecosystems. By enabling targeted interventions, this approach facilitates the preservation of seagrass meadows, which are also critical for carbon sequestration and the sustainability of marine habitats. ]]></content:encoded> <dc:title>Remote Sensing Tools for Monitoring Marine Phanerogams: A Review of Sentinel and Landsat Applications</dc:title> <dc:creator>Noelia Campillo-Tamarit</dc:creator> <dc:creator>Juan V铆ctor Molner</dc:creator> <dc:creator>Juan M. Soria</dc:creator> <dc:identifier>doi: 10.3390/jmse13020292</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-04</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-04</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Review</prism:section> <prism:startingPage>292</prism:startingPage> <prism:doi>10.3390/jmse13020292</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/292</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/291"> <title>JMSE, Vol. 13, Pages 291: Species Identification and Frequency Characteristic of Japanese Anchovy (Engraulis japonicus) Using Hydro-Acoustics</title> <link>https://www.mdpi.com/2077-1312/13/2/291</link> <description>In this study, the KRM (Kirchhoff-ray mode) model was used to identify the acoustic scattering characteristics of anchovies according to frequency, and the school detection method and dB-difference method were used to identify the acoustic signals of Japanese anchovy on the echogram. The TS (target strength) values of anchovies were checked in the echograms of areas where more than 95% of anchovies were collected to establish frequency range. In addition, the parameter values were set by estimating the size of the anchovy school from the echogram, and the echo signal of the anchovy was identified by school detection using the set parameter values. The results showed that the average TS fluctuations of anchovies were larger for small-sized anchovies (5.5 cm) than for large-sized anchovies (16.9 cm), but TS fluctuations after frequency 130 kHz showed similar trends. Species identification analysis identified only the echo signal of anchovies in the echograms, with depths of 20&amp;ndash;70 m for anchovies and 90&amp;ndash;110 m for other fish species.</description> <pubDate>2025-02-04</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 291: Species Identification and Frequency Characteristic of Japanese Anchovy (Engraulis japonicus) Using Hydro-Acoustics Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/291">doi: 10.3390/jmse13020291</a> Authors: Geunchang Park Tohru Mukai Kyounghoon Lee In this study, the KRM (Kirchhoff-ray mode) model was used to identify the acoustic scattering characteristics of anchovies according to frequency, and the school detection method and dB-difference method were used to identify the acoustic signals of Japanese anchovy on the echogram. The TS (target strength) values of anchovies were checked in the echograms of areas where more than 95% of anchovies were collected to establish frequency range. In addition, the parameter values were set by estimating the size of the anchovy school from the echogram, and the echo signal of the anchovy was identified by school detection using the set parameter values. The results showed that the average TS fluctuations of anchovies were larger for small-sized anchovies (5.5 cm) than for large-sized anchovies (16.9 cm), but TS fluctuations after frequency 130 kHz showed similar trends. Species identification analysis identified only the echo signal of anchovies in the echograms, with depths of 20&amp;ndash;70 m for anchovies and 90&amp;ndash;110 m for other fish species. ]]></content:encoded> <dc:title>Species Identification and Frequency Characteristic of Japanese Anchovy (Engraulis japonicus) Using Hydro-Acoustics</dc:title> <dc:creator>Geunchang Park</dc:creator> <dc:creator>Tohru Mukai</dc:creator> <dc:creator>Kyounghoon Lee</dc:creator> <dc:identifier>doi: 10.3390/jmse13020291</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-04</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-04</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>291</prism:startingPage> <prism:doi>10.3390/jmse13020291</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/291</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/290"> <title>JMSE, Vol. 13, Pages 290: Observations and Numerical Modelling of the Sumatra Tsunami of 28 March 2005</title> <link>https://www.mdpi.com/2077-1312/13/2/290</link> <description>On 28 March 2005, a major Mw 8.6 earthquake occurred near Nias and Simeulueislands, in the vicinity of northwestern Sumatra (Indonesia). The earthquake generated a significant tsunami. Although it was not as destructive as the 2004 Sumatra tsunami, the 2005 event was of sufficient strength to be recorded by tide gauges throughout the entire Indian Ocean. We selected 12 records for analysis, most from open-ocean islands but also some from continental stations. The maximum wave heights were measured at Salalah (Oman) (87 cm), Colombo (Sri Lanka), Pointe La Rue (Seychelles) and Rodrigues Island (53&amp;ndash;54 cm). The dominant wave periods, estimated from frequency&amp;ndash;time (f-t) diagrams, were 60&amp;ndash;66 min, 40&amp;ndash;48 min, and 20 min, which we assume are associated with the 2005 tsunami source. From the same stations, we calculated the mean ratio of the 2004 to 2005 tsunami heights as 5.11 &amp;plusmn; 0.60, with the maximum and minimum heights to the west and south of the source region as 9.0 and 2.49, respectively. We also used these data to estimate the mean energy index, E0 = 65 cm2, for the 2005 tsunami, which was 16 times smaller than for the 2004 event. The USGS seismic solution was used to construct a numerical model of the 2005 tsunami and to simulate the tsunami waveforms for all 12 tide gauge stations. The results of the numerical computations were in general agreement with the observations and enabled us to map the spatial wave field of the event. To estimate the influence of location and orientation of the source area on the propagating tsunami waves, we undertook a set of additional numerical experiments and found that this influence is substantial and that these factors explain some of the differences between the physical properties of the 2004 and 2005 events.</description> <pubDate>2025-02-04</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 290: Observations and Numerical Modelling of the Sumatra Tsunami of 28 March 2005 Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/290">doi: 10.3390/jmse13020290</a> Authors: Alisa Medvedeva Alexander Rabinovich On 28 March 2005, a major Mw 8.6 earthquake occurred near Nias and Simeulueislands, in the vicinity of northwestern Sumatra (Indonesia). The earthquake generated a significant tsunami. Although it was not as destructive as the 2004 Sumatra tsunami, the 2005 event was of sufficient strength to be recorded by tide gauges throughout the entire Indian Ocean. We selected 12 records for analysis, most from open-ocean islands but also some from continental stations. The maximum wave heights were measured at Salalah (Oman) (87 cm), Colombo (Sri Lanka), Pointe La Rue (Seychelles) and Rodrigues Island (53&amp;ndash;54 cm). The dominant wave periods, estimated from frequency&amp;ndash;time (f-t) diagrams, were 60&amp;ndash;66 min, 40&amp;ndash;48 min, and 20 min, which we assume are associated with the 2005 tsunami source. From the same stations, we calculated the mean ratio of the 2004 to 2005 tsunami heights as 5.11 &amp;plusmn; 0.60, with the maximum and minimum heights to the west and south of the source region as 9.0 and 2.49, respectively. We also used these data to estimate the mean energy index, E0 = 65 cm2, for the 2005 tsunami, which was 16 times smaller than for the 2004 event. The USGS seismic solution was used to construct a numerical model of the 2005 tsunami and to simulate the tsunami waveforms for all 12 tide gauge stations. The results of the numerical computations were in general agreement with the observations and enabled us to map the spatial wave field of the event. To estimate the influence of location and orientation of the source area on the propagating tsunami waves, we undertook a set of additional numerical experiments and found that this influence is substantial and that these factors explain some of the differences between the physical properties of the 2004 and 2005 events. ]]></content:encoded> <dc:title>Observations and Numerical Modelling of the Sumatra Tsunami of 28 March 2005</dc:title> <dc:creator>Alisa Medvedeva</dc:creator> <dc:creator>Alexander Rabinovich</dc:creator> <dc:identifier>doi: 10.3390/jmse13020290</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-04</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-04</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>290</prism:startingPage> <prism:doi>10.3390/jmse13020290</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/290</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/289"> <title>JMSE, Vol. 13, Pages 289: Design and Demonstration of an Underwater High-Stability Rapid Cross-Domain Unpowered Vehicle</title> <link>https://www.mdpi.com/2077-1312/13/2/289</link> <description>Unpowered vehicles are designed for subaquatic operation and are capable of operating rapidly cross-domain. This paper presents a refined and optimized design for a high-stability rapid cross-domain unpowered vehicle. The use of a compact, uniquely configured gas generator maximizes the rapidity of the ascent phase, achieving an average underwater speed of more than 3.5 m/s, all without the need for an additional propulsion system. To enhance the stability of the unpowered vehicle during the cross-domain phase, a recoil compensation deceleration device (RCDD) was engineered. This device, which uses a combination of springs and electromagnets, significantly increases both the launch capability and the attitude adjustment capability, by 50%. Furthermore, to facilitate rapid launch in real marine environments and investigate the attitudes before and after crossing domains, a rapid cross-domain launch mechanism is introduced. Through multiple sea trials, the results indicate that the unpowered vehicle can complete the launch process within 4 s under sea state 3 conditions. The unpowered vehicle provides an effective solution for rapid cross-domain operation in complex marine environments.</description> <pubDate>2025-02-04</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 289: Design and Demonstration of an Underwater High-Stability Rapid Cross-Domain Unpowered Vehicle Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/289">doi: 10.3390/jmse13020289</a> Authors: Zhiyi Yang Kaiyan Hou Yu Cui Lu Liu Jinglong Wen Haozhe Zhang Zujiang Yuan Dan Liu Chenyang Xue Unpowered vehicles are designed for subaquatic operation and are capable of operating rapidly cross-domain. This paper presents a refined and optimized design for a high-stability rapid cross-domain unpowered vehicle. The use of a compact, uniquely configured gas generator maximizes the rapidity of the ascent phase, achieving an average underwater speed of more than 3.5 m/s, all without the need for an additional propulsion system. To enhance the stability of the unpowered vehicle during the cross-domain phase, a recoil compensation deceleration device (RCDD) was engineered. This device, which uses a combination of springs and electromagnets, significantly increases both the launch capability and the attitude adjustment capability, by 50%. Furthermore, to facilitate rapid launch in real marine environments and investigate the attitudes before and after crossing domains, a rapid cross-domain launch mechanism is introduced. Through multiple sea trials, the results indicate that the unpowered vehicle can complete the launch process within 4 s under sea state 3 conditions. The unpowered vehicle provides an effective solution for rapid cross-domain operation in complex marine environments. ]]></content:encoded> <dc:title>Design and Demonstration of an Underwater High-Stability Rapid Cross-Domain Unpowered Vehicle</dc:title> <dc:creator>Zhiyi Yang</dc:creator> <dc:creator>Kaiyan Hou</dc:creator> <dc:creator>Yu Cui</dc:creator> <dc:creator>Lu Liu</dc:creator> <dc:creator>Jinglong Wen</dc:creator> <dc:creator>Haozhe Zhang</dc:creator> <dc:creator>Zujiang Yuan</dc:creator> <dc:creator>Dan Liu</dc:creator> <dc:creator>Chenyang Xue</dc:creator> <dc:identifier>doi: 10.3390/jmse13020289</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-04</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-04</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>289</prism:startingPage> <prism:doi>10.3390/jmse13020289</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/289</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/288"> <title>JMSE, Vol. 13, Pages 288: Spatial Distribution of Illex argentinus in Different Life Stages of Mesoscale Eddies in Patagonian Waters</title> <link>https://www.mdpi.com/2077-1312/13/2/288</link> <description>Mesoscale eddies are known to influence the abundance and distribution of oceanic cephalopods. However, little is known about these effects in the southwest Atlantic Ocean. Therefore, this study analyzed the variations in environmental conditions and the resource abundance, spatial distribution, and habitat suitability of Illex argentinus within different life stages of cyclonic (CE) and anticyclonic (AE) eddies in Patagonian waters. From a comparison of squid abundance between CEs and AEs at each life stage, it was found that I. argentinus gradually increased in abundance after eddy formation, that abundance peaked during eddy maturation and that it subsequently decreased during the eddies&amp;rsquo; decay phase. Spatially, squid resources in AEs were primarily concentrated in the northwest and southeast peripheral regions of the eddy, while in CEs, resources were more concentrated in the outer regions, on the western side of the eddy. Environmental factor analysis revealed that sea surface temperature (SST) and temperature at 200 m depth (T200m) in both CEs and AEs reached their lowest values during the intensification and maturation phases of the eddies. Chlorophyll a (Chl-a) concentrations were significantly higher in CEs than in AEs from the formation to the maturation phase; however, during eddy decay, Chl-a concentrations were higher in AEs. According to a comparison of the suitability index (SI) for each environmental factor and the habitat suitability index (HSI) model, SISST, SIT200m, and SIChl-a in AEs increased and then decreased with eddy evolution, with optimal SI values occurring during the intensification phase. In CEs, SISST and SIT200m also increased and then decreased, with optimal SISST and SIT200m occurring during the intensification and maturation phases, respectively, with little variation in SIChl-a across the life cycle of CEs. The HSI in both types of eddies gradually increased from the formation phase, reached a peak during maturation, and significantly decreased during eddy decay. Overall, this study indicated that habitat suitability and resource abundance for I. argentinus were highest during the maturation phase of the eddies.</description> <pubDate>2025-02-04</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 288: Spatial Distribution of Illex argentinus in Different Life Stages of Mesoscale Eddies in Patagonian Waters Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/288">doi: 10.3390/jmse13020288</a> Authors: Lichuan Zhang Ping Zhang Zhong Zhang Wei Yu Mesoscale eddies are known to influence the abundance and distribution of oceanic cephalopods. However, little is known about these effects in the southwest Atlantic Ocean. Therefore, this study analyzed the variations in environmental conditions and the resource abundance, spatial distribution, and habitat suitability of Illex argentinus within different life stages of cyclonic (CE) and anticyclonic (AE) eddies in Patagonian waters. From a comparison of squid abundance between CEs and AEs at each life stage, it was found that I. argentinus gradually increased in abundance after eddy formation, that abundance peaked during eddy maturation and that it subsequently decreased during the eddies&amp;rsquo; decay phase. Spatially, squid resources in AEs were primarily concentrated in the northwest and southeast peripheral regions of the eddy, while in CEs, resources were more concentrated in the outer regions, on the western side of the eddy. Environmental factor analysis revealed that sea surface temperature (SST) and temperature at 200 m depth (T200m) in both CEs and AEs reached their lowest values during the intensification and maturation phases of the eddies. Chlorophyll a (Chl-a) concentrations were significantly higher in CEs than in AEs from the formation to the maturation phase; however, during eddy decay, Chl-a concentrations were higher in AEs. According to a comparison of the suitability index (SI) for each environmental factor and the habitat suitability index (HSI) model, SISST, SIT200m, and SIChl-a in AEs increased and then decreased with eddy evolution, with optimal SI values occurring during the intensification phase. In CEs, SISST and SIT200m also increased and then decreased, with optimal SISST and SIT200m occurring during the intensification and maturation phases, respectively, with little variation in SIChl-a across the life cycle of CEs. The HSI in both types of eddies gradually increased from the formation phase, reached a peak during maturation, and significantly decreased during eddy decay. Overall, this study indicated that habitat suitability and resource abundance for I. argentinus were highest during the maturation phase of the eddies. ]]></content:encoded> <dc:title>Spatial Distribution of Illex argentinus in Different Life Stages of Mesoscale Eddies in Patagonian Waters</dc:title> <dc:creator>Lichuan Zhang</dc:creator> <dc:creator>Ping Zhang</dc:creator> <dc:creator>Zhong Zhang</dc:creator> <dc:creator>Wei Yu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020288</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-04</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-04</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>288</prism:startingPage> <prism:doi>10.3390/jmse13020288</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/288</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/287"> <title>JMSE, Vol. 13, Pages 287: A Prediction of Estuary Wetland Vegetation with Satellite Images</title> <link>https://www.mdpi.com/2077-1312/13/2/287</link> <description>Estuarine wetlands are the transition zone between marine, freshwater, and terrestrial ecosystems and are more ecologically fragile. In recent years, the spread of exotic vegetation, specifically Spartina alterniflora, in the Yellow River estuary wetlands has significantly encroached upon the habitats of native species such as Phragmites australis, Suaeda glauca Bunge, and Tamarix chinensis Lour. With advances in land prediction modeling, predicting wetland vegetation distribution can aid management and decision-making for ecological restoration. We selected the core area as the study object and coupled the hydrological model MIKE 21 with the PLUS model to predict the potential future distribution of invasive and dominant species in the region. (1) Based on the fine classification results from satellite images of GF1/G2/G5, we gained an understanding of the changes in wetland vegetation types in the core area of the reserve in 2018 and 2020. (2) Using public data such as ERA5 and GEO as input for basic environmental data, using MIKE 21 to provide high-spatial-resolution hydrodynamic parameters for the PLUS model as an environmental driver, we modeled the spatial distribution of various wetland vegetation in the Yellow River estuary wetland in Dongying under different artificial restoration measures. (3) We predicted the 2022 distribution of typical vegetation in the region, used the classification results of GF6 as the actual distribution, compared the spatial distribution with the actual distribution, and obtained a kappa coefficient of 0.78; the predicted values of the model are highly consistent with the true values. This study combines the fine classification results of vegetation based on hyperspectral remote sensing, the construction of a coupled model, and the prediction effect of typical species, providing a reference for constructing and optimizing the vegetation prediction model of estuarine wetlands. It also allows scientific and effective decision-making for the management of ecological restoration of delta wetlands.</description> <pubDate>2025-02-04</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 287: A Prediction of Estuary Wetland Vegetation with Satellite Images Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/287">doi: 10.3390/jmse13020287</a> Authors: Min Yang Bin Guo Ning Gao Yang Yu Xiaoli Song Yanfeng Gu Estuarine wetlands are the transition zone between marine, freshwater, and terrestrial ecosystems and are more ecologically fragile. In recent years, the spread of exotic vegetation, specifically Spartina alterniflora, in the Yellow River estuary wetlands has significantly encroached upon the habitats of native species such as Phragmites australis, Suaeda glauca Bunge, and Tamarix chinensis Lour. With advances in land prediction modeling, predicting wetland vegetation distribution can aid management and decision-making for ecological restoration. We selected the core area as the study object and coupled the hydrological model MIKE 21 with the PLUS model to predict the potential future distribution of invasive and dominant species in the region. (1) Based on the fine classification results from satellite images of GF1/G2/G5, we gained an understanding of the changes in wetland vegetation types in the core area of the reserve in 2018 and 2020. (2) Using public data such as ERA5 and GEO as input for basic environmental data, using MIKE 21 to provide high-spatial-resolution hydrodynamic parameters for the PLUS model as an environmental driver, we modeled the spatial distribution of various wetland vegetation in the Yellow River estuary wetland in Dongying under different artificial restoration measures. (3) We predicted the 2022 distribution of typical vegetation in the region, used the classification results of GF6 as the actual distribution, compared the spatial distribution with the actual distribution, and obtained a kappa coefficient of 0.78; the predicted values of the model are highly consistent with the true values. This study combines the fine classification results of vegetation based on hyperspectral remote sensing, the construction of a coupled model, and the prediction effect of typical species, providing a reference for constructing and optimizing the vegetation prediction model of estuarine wetlands. It also allows scientific and effective decision-making for the management of ecological restoration of delta wetlands. ]]></content:encoded> <dc:title>A Prediction of Estuary Wetland Vegetation with Satellite Images</dc:title> <dc:creator>Min Yang</dc:creator> <dc:creator>Bin Guo</dc:creator> <dc:creator>Ning Gao</dc:creator> <dc:creator>Yang Yu</dc:creator> <dc:creator>Xiaoli Song</dc:creator> <dc:creator>Yanfeng Gu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020287</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-04</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-04</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>287</prism:startingPage> <prism:doi>10.3390/jmse13020287</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/287</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/286"> <title>JMSE, Vol. 13, Pages 286: Study on Sound Field Properties of Parametric Array Under the Influence of Underwater Waveguide Interface Scattering Based on Non-Paraxial Model&mdash;Theory and Experiment</title> <link>https://www.mdpi.com/2077-1312/13/2/286</link> <description>This paper theoretically and experimentally studies the effect of underwater waveguide interface scattering on the nonlinear sound field characteristics of parametric array (PA) radiation. Based on the image source method, the components of the sound field in the waveguide are first analyzed. Then, a non-paraxial model is developed to account for the influence of interface scattering. This model enables accurate calculation of the wide-angle sound field. The impact of the sound source depth and the interface reflection coefficient on the distribution of the difference-frequency wave (DFW) sound field in the waveguide is studied. The interface alters the phase distribution of the DFW&amp;rsquo;s virtual source density function, thereby affecting the sound field accumulation process. Waveguide interfaces with different absorption coefficients influence the amplitude oscillation caused by interface reflection and change the sidelobe size of the DFW beam. The DFW sound field distribution is measured at three typical frequencies. Simulation and experimental results show that the attenuation of the DFW&amp;rsquo;s axial sound pressure level in the waveguide oscillates, and the DFW&amp;rsquo;s beamwidth gradually widens as the frequency decreases. The calculated results from the proposed model agree well with the measured data, with average errors along the sound axis and depth being less than 3 dB and 6 dB, respectively. This demonstrates the model&amp;rsquo;s superior applicability compared to the existing free-field model.</description> <pubDate>2025-02-04</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 286: Study on Sound Field Properties of Parametric Array Under the Influence of Underwater Waveguide Interface Scattering Based on Non-Paraxial Model&mdash;Theory and Experiment Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/286">doi: 10.3390/jmse13020286</a> Authors: Yuan Cao Jie Shi Jiangyi Zhang Yuezhu Cheng Haokang Shi This paper theoretically and experimentally studies the effect of underwater waveguide interface scattering on the nonlinear sound field characteristics of parametric array (PA) radiation. Based on the image source method, the components of the sound field in the waveguide are first analyzed. Then, a non-paraxial model is developed to account for the influence of interface scattering. This model enables accurate calculation of the wide-angle sound field. The impact of the sound source depth and the interface reflection coefficient on the distribution of the difference-frequency wave (DFW) sound field in the waveguide is studied. The interface alters the phase distribution of the DFW&amp;rsquo;s virtual source density function, thereby affecting the sound field accumulation process. Waveguide interfaces with different absorption coefficients influence the amplitude oscillation caused by interface reflection and change the sidelobe size of the DFW beam. The DFW sound field distribution is measured at three typical frequencies. Simulation and experimental results show that the attenuation of the DFW&amp;rsquo;s axial sound pressure level in the waveguide oscillates, and the DFW&amp;rsquo;s beamwidth gradually widens as the frequency decreases. The calculated results from the proposed model agree well with the measured data, with average errors along the sound axis and depth being less than 3 dB and 6 dB, respectively. This demonstrates the model&amp;rsquo;s superior applicability compared to the existing free-field model. ]]></content:encoded> <dc:title>Study on Sound Field Properties of Parametric Array Under the Influence of Underwater Waveguide Interface Scattering Based on Non-Paraxial Model&amp;mdash;Theory and Experiment</dc:title> <dc:creator>Yuan Cao</dc:creator> <dc:creator>Jie Shi</dc:creator> <dc:creator>Jiangyi Zhang</dc:creator> <dc:creator>Yuezhu Cheng</dc:creator> <dc:creator>Haokang Shi</dc:creator> <dc:identifier>doi: 10.3390/jmse13020286</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-04</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-04</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>286</prism:startingPage> <prism:doi>10.3390/jmse13020286</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/286</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/285"> <title>JMSE, Vol. 13, Pages 285: Projecting Barrier Beach Vulnerability to Waves and Sea-Level Rise Under Climate Change</title> <link>https://www.mdpi.com/2077-1312/13/2/285</link> <description>Long-term impacts of sea-level changes and trends in storm magnitude and frequency along the Mediterranean coasts are key aspects of effective coastal adaptation strategies. In enclosed basins such as a gulf, this requires a step beyond global and regional analysis toward high-resolution modeling of hazards and vulnerabilities at different time scales. We present the compound future projection of static (relative sea level) and dynamic (wind-wave) impacts on the geomorphological evolution of a vulnerable sandy coastal plan located in south Sardinia (west Mediterranean Sea). Based on local temporal trends in Hs (8 mm yr&amp;minus;1) and sea level (5.4 mm yr&amp;minus;1), a 2-year return time flood scenario at 2100 shows the flattening of the submerged morphologies triggering the process of marine embayment. The research proposes adaptation strategies to be adopted to design the projected new coastal area under vulnerabilities at local and territorial scales.</description> <pubDate>2025-02-03</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 285: Projecting Barrier Beach Vulnerability to Waves and Sea-Level Rise Under Climate Change Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/285">doi: 10.3390/jmse13020285</a> Authors: Andrea Sulis Fabrizio Antonioli Andrea Atzeni Andrea Carboni Giacomo Deiana Paolo E. Orr霉 Valeria Lo Presti Silvia Serreli Long-term impacts of sea-level changes and trends in storm magnitude and frequency along the Mediterranean coasts are key aspects of effective coastal adaptation strategies. In enclosed basins such as a gulf, this requires a step beyond global and regional analysis toward high-resolution modeling of hazards and vulnerabilities at different time scales. We present the compound future projection of static (relative sea level) and dynamic (wind-wave) impacts on the geomorphological evolution of a vulnerable sandy coastal plan located in south Sardinia (west Mediterranean Sea). Based on local temporal trends in Hs (8 mm yr&amp;minus;1) and sea level (5.4 mm yr&amp;minus;1), a 2-year return time flood scenario at 2100 shows the flattening of the submerged morphologies triggering the process of marine embayment. The research proposes adaptation strategies to be adopted to design the projected new coastal area under vulnerabilities at local and territorial scales. ]]></content:encoded> <dc:title>Projecting Barrier Beach Vulnerability to Waves and Sea-Level Rise Under Climate Change</dc:title> <dc:creator>Andrea Sulis</dc:creator> <dc:creator>Fabrizio Antonioli</dc:creator> <dc:creator>Andrea Atzeni</dc:creator> <dc:creator>Andrea Carboni</dc:creator> <dc:creator>Giacomo Deiana</dc:creator> <dc:creator>Paolo E. Orr霉</dc:creator> <dc:creator>Valeria Lo Presti</dc:creator> <dc:creator>Silvia Serreli</dc:creator> <dc:identifier>doi: 10.3390/jmse13020285</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-03</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-03</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>285</prism:startingPage> <prism:doi>10.3390/jmse13020285</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/285</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/283"> <title>JMSE, Vol. 13, Pages 283: A Semi-Analytical Method to Design a Dynamic Vibration Absorber for Coupled Plate Structures of Offshore Platforms</title> <link>https://www.mdpi.com/2077-1312/13/2/283</link> <description>Coupled plate structures composed of stiffened plates and sub-plates have been widely used in marine engineering practice. Meanwhile, the low-frequency multi-linear spectrum vibration control of the coupled stiffened plate structures has become necessary and meaningful. However, the design efficiency of the dynamic vibration absorber of the corresponding structure is still low. In the present study, a mathematical model of coupled plate structures and a dynamic vibration absorber is introduced to improve design efficiency. Subsequently, an experiment is designed to verify the effectiveness and advantages of the current method. The reliability of the current mathematical model is verified by comparing it with modal experiment results. Moreover, the equivalent mass solution efficiency is greatly improved by comparing it with FEM. Finally, a comparison experiment of the dynamic vibration absorber has also been conducted to further verify the effectiveness of the current method. The semi-analytical method proposed in the current research may be useful when designing dynamic vibration absorbers for the coupled plate structures of offshore platforms.</description> <pubDate>2025-02-03</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 283: A Semi-Analytical Method to Design a Dynamic Vibration Absorber for Coupled Plate Structures of Offshore Platforms Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/283">doi: 10.3390/jmse13020283</a> Authors: Yuan Du Fuxin Jia Yang Tang Jiajun Zheng Yucheng Zou Yong Ma Coupled plate structures composed of stiffened plates and sub-plates have been widely used in marine engineering practice. Meanwhile, the low-frequency multi-linear spectrum vibration control of the coupled stiffened plate structures has become necessary and meaningful. However, the design efficiency of the dynamic vibration absorber of the corresponding structure is still low. In the present study, a mathematical model of coupled plate structures and a dynamic vibration absorber is introduced to improve design efficiency. Subsequently, an experiment is designed to verify the effectiveness and advantages of the current method. The reliability of the current mathematical model is verified by comparing it with modal experiment results. Moreover, the equivalent mass solution efficiency is greatly improved by comparing it with FEM. Finally, a comparison experiment of the dynamic vibration absorber has also been conducted to further verify the effectiveness of the current method. The semi-analytical method proposed in the current research may be useful when designing dynamic vibration absorbers for the coupled plate structures of offshore platforms. ]]></content:encoded> <dc:title>A Semi-Analytical Method to Design a Dynamic Vibration Absorber for Coupled Plate Structures of Offshore Platforms</dc:title> <dc:creator>Yuan Du</dc:creator> <dc:creator>Fuxin Jia</dc:creator> <dc:creator>Yang Tang</dc:creator> <dc:creator>Jiajun Zheng</dc:creator> <dc:creator>Yucheng Zou</dc:creator> <dc:creator>Yong Ma</dc:creator> <dc:identifier>doi: 10.3390/jmse13020283</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-03</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-03</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>283</prism:startingPage> <prism:doi>10.3390/jmse13020283</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/283</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/282"> <title>JMSE, Vol. 13, Pages 282: Optimization of Key Parameters of Fracturing Flooding Development in Offshore Reservoirs with Low Permeability Based on Numerical Modeling Approach</title> <link>https://www.mdpi.com/2077-1312/13/2/282</link> <description>Fracturing flooding is a new technology that combines traditional conventional water drive, chemical drive, and hydraulic fracturing technologies and injects water under proximity fracture pressure to increase the wave area. It is currently applied in onshore low-permeability oilfields with good results, but the research on the design method of fracturing flooding in offshore low-permeability reservoirs is still lacking. Numerical simulation studies of well fracturing flooding are needed to optimize the key parameters of fracturing flooding development. This study simulates the real-time fracture dynamic expansion process of micro-level fracture expansion for hydraulic fracturing, combines it with a numerical simulation of well pressure-driving, and finally optimizes the parameters of hydraulic flooding. By studying the fracture expansion law, this study determined that the total amount of injection volume had a large influence on both fracture half-length and inflow capacity; the larger the injection rate, the larger the fracture half-length, but the inflow capacity was basically unchanged. It was also found that multiple rounds of fracturing flooding had no effect on fracture morphology or length. In studying the key fracturing flooding parameters in oil wells, it was concluded that the higher the total injection amount, the higher the oil increase in fracturing flooding and the wider the wave area of pressure-driving. Moreover, the higher the displacement, the higher the pressure near the bottom of the well, but there was little difference in the spreading area; in addition, the longer the well shut-in time, the higher the early oil production. Finally, these results were combined with the fracture expansion mechanism model and A21 well model, and the analysis of fracturing flooding parameters based on the simulation results allowed for the following recommendations to be made: the total amount of fracturing flooding injection should be 15,000 m3, the injection rate should be 6 m3/min, the simmering time should be 3&amp;ndash;7 days, and only one round of fracturing flooding is required. The mechanism of fracture expansion revealed in this paper can guide the design of fracturing flooding programs in the process of reservoir fracturing flooding development, which is of some significance to the development of the fracturing flooding of offshore reservoirs with low permeability.</description> <pubDate>2025-02-01</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 282: Optimization of Key Parameters of Fracturing Flooding Development in Offshore Reservoirs with Low Permeability Based on Numerical Modeling Approach Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/282">doi: 10.3390/jmse13020282</a> Authors: Zitong Zhao Shan Jiang Ting Lei Jinwei Wang Yafei Zhang Fracturing flooding is a new technology that combines traditional conventional water drive, chemical drive, and hydraulic fracturing technologies and injects water under proximity fracture pressure to increase the wave area. It is currently applied in onshore low-permeability oilfields with good results, but the research on the design method of fracturing flooding in offshore low-permeability reservoirs is still lacking. Numerical simulation studies of well fracturing flooding are needed to optimize the key parameters of fracturing flooding development. This study simulates the real-time fracture dynamic expansion process of micro-level fracture expansion for hydraulic fracturing, combines it with a numerical simulation of well pressure-driving, and finally optimizes the parameters of hydraulic flooding. By studying the fracture expansion law, this study determined that the total amount of injection volume had a large influence on both fracture half-length and inflow capacity; the larger the injection rate, the larger the fracture half-length, but the inflow capacity was basically unchanged. It was also found that multiple rounds of fracturing flooding had no effect on fracture morphology or length. In studying the key fracturing flooding parameters in oil wells, it was concluded that the higher the total injection amount, the higher the oil increase in fracturing flooding and the wider the wave area of pressure-driving. Moreover, the higher the displacement, the higher the pressure near the bottom of the well, but there was little difference in the spreading area; in addition, the longer the well shut-in time, the higher the early oil production. Finally, these results were combined with the fracture expansion mechanism model and A21 well model, and the analysis of fracturing flooding parameters based on the simulation results allowed for the following recommendations to be made: the total amount of fracturing flooding injection should be 15,000 m3, the injection rate should be 6 m3/min, the simmering time should be 3&amp;ndash;7 days, and only one round of fracturing flooding is required. The mechanism of fracture expansion revealed in this paper can guide the design of fracturing flooding programs in the process of reservoir fracturing flooding development, which is of some significance to the development of the fracturing flooding of offshore reservoirs with low permeability. ]]></content:encoded> <dc:title>Optimization of Key Parameters of Fracturing Flooding Development in Offshore Reservoirs with Low Permeability Based on Numerical Modeling Approach</dc:title> <dc:creator>Zitong Zhao</dc:creator> <dc:creator>Shan Jiang</dc:creator> <dc:creator>Ting Lei</dc:creator> <dc:creator>Jinwei Wang</dc:creator> <dc:creator>Yafei Zhang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020282</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-01</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-01</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>282</prism:startingPage> <prism:doi>10.3390/jmse13020282</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/282</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/284"> <title>JMSE, Vol. 13, Pages 284: Probability Stability Evaluation of Coral Reef Limestone Reef Slopes Under Earthquake</title> <link>https://www.mdpi.com/2077-1312/13/2/284</link> <description>With the rapid development of island construction and the frequent occurrence of natural disasters, the stability of coral reef slopes is attracting increasing attention. This study aims to assess the dynamic stability and instability risks of coral reef slopes under different earthquake intensities. Geological data were integrated, and the Newmark method and finite element analysis were employed for probabilistic stability assessment and permanent displacement evaluation, leading to the development of a validated model for slope stability assessment. The study explored the effects of varying earthquake intensities on slope stability. Results indicate that the stratified structure significantly influences stability. Reef limestone slopes exhibited higher stability, whereas multi-layered slopes, due to looseness, were less stable. Both slope types remained stable under static conditions. Earthquake intensity substantially impacted stability, with multi-layered slopes showing instability probabilities of 48% and 100% under peak ground accelerations (PGA) of 0.3 g and 0.4 g. Under extreme seismic conditions, the permanent displacement of multi-layered coral reef slopes significantly increased. This study aims to fill the gap in previous research by incorporating the random distribution of stratigraphic parameters, conducting probabilistic stability analysis based on the random distribution of geological parameters, and thereby providing references for island reef engineering construction.</description> <pubDate>2025-02-01</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 284: Probability Stability Evaluation of Coral Reef Limestone Reef Slopes Under Earthquake Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/284">doi: 10.3390/jmse13020284</a> Authors: Ruize Ma Baifeng Ji Longya Zhang Shuang Pan Kaimeng Hu With the rapid development of island construction and the frequent occurrence of natural disasters, the stability of coral reef slopes is attracting increasing attention. This study aims to assess the dynamic stability and instability risks of coral reef slopes under different earthquake intensities. Geological data were integrated, and the Newmark method and finite element analysis were employed for probabilistic stability assessment and permanent displacement evaluation, leading to the development of a validated model for slope stability assessment. The study explored the effects of varying earthquake intensities on slope stability. Results indicate that the stratified structure significantly influences stability. Reef limestone slopes exhibited higher stability, whereas multi-layered slopes, due to looseness, were less stable. Both slope types remained stable under static conditions. Earthquake intensity substantially impacted stability, with multi-layered slopes showing instability probabilities of 48% and 100% under peak ground accelerations (PGA) of 0.3 g and 0.4 g. Under extreme seismic conditions, the permanent displacement of multi-layered coral reef slopes significantly increased. This study aims to fill the gap in previous research by incorporating the random distribution of stratigraphic parameters, conducting probabilistic stability analysis based on the random distribution of geological parameters, and thereby providing references for island reef engineering construction. ]]></content:encoded> <dc:title>Probability Stability Evaluation of Coral Reef Limestone Reef Slopes Under Earthquake</dc:title> <dc:creator>Ruize Ma</dc:creator> <dc:creator>Baifeng Ji</dc:creator> <dc:creator>Longya Zhang</dc:creator> <dc:creator>Shuang Pan</dc:creator> <dc:creator>Kaimeng Hu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020284</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-02-01</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-02-01</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>284</prism:startingPage> <prism:doi>10.3390/jmse13020284</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/284</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/281"> <title>JMSE, Vol. 13, Pages 281: A Comparative Analysis of Growth, Survival, and Combining Ability Based on Diallel Crosses Among Three Selected Lines of the Fujian Oyster Crassostrea angulata with Normal, Golden, and Black Shell Colors</title> <link>https://www.mdpi.com/2077-1312/13/2/281</link> <description>Crossing between selected lines could combine the additive genetic variance accumulated within the lines and the non-additive genetic variance between the lines in the genetic improvement of aquatic animals, thus obtaining progeny with favorable traits. However, the value of this breeding strategy has not been investigated in the Fujian oyster Crassostrea angulata due to the lack of available sufficiently selected lines. In this study, a complete 3 &amp;times; 3 diallel cross was established between the normal (N), golden (G), and black (B) shell lines of C. angulata. The growth (shell height and living weight) and survival of three purebred groups and six hybrid groups under three environments (Luoyu, Jiangkou, and Houhai) were comprehensively evaluated during the larval and grow-out stages. The general combining ability (GCA) of the parental lines and the specific combining ability (SCA) of the hybrid groups were also estimated. The shell heights of the hybrid groups were significantly lower than those of their parental groups on day 25, exhibiting negative heterosis (MPH: &amp;minus;13.01 to &amp;minus;1.45; HPH: &amp;minus;16.69 to &amp;minus;5.76). Meanwhile, the survival rates of the hybrids were significantly higher than those of the parental groups. A negative value of SCA was recorded for NG (N&amp;#9792; &amp;times; G&amp;#9794;) (&amp;minus;0.031), which was in line with its lower survival rate on day 25. Significant heterosis was observed in the growth and survival of each hybrid group during the grow-out stage. The shell height and living weight of the hybrid groups were significantly higher in Houhai than in Luoyu and Jiangkou, but the survival rate in Houhai was significantly lower than in the other two sites. BG (B&amp;#9792; &amp;times; G&amp;#9794;) and GB (G&amp;#9792; &amp;times; B&amp;#9794;) had higher SCA values than the other four groups, which was consistent with their superior traits. The heterosis of shell height, living weight, and survival rate of BG was significantly greater than in the other five hybrid groups, which could be used as potential parents for breeding high-quality diploid and triploid Fujian oysters. This study demonstrated that the traits of C. angulata could be significantly improved by crossing between different selected lines, providing a reference for evaluating the utilization value of non-additive genetic effects (heterosis) between selected lines in bivalves.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 281: A Comparative Analysis of Growth, Survival, and Combining Ability Based on Diallel Crosses Among Three Selected Lines of the Fujian Oyster Crassostrea angulata with Normal, Golden, and Black Shell Colors Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/281">doi: 10.3390/jmse13020281</a> Authors: Yuanxin Liang Hong Hu Zhenzong Pan Chengxun Xu Qi Li Crossing between selected lines could combine the additive genetic variance accumulated within the lines and the non-additive genetic variance between the lines in the genetic improvement of aquatic animals, thus obtaining progeny with favorable traits. However, the value of this breeding strategy has not been investigated in the Fujian oyster Crassostrea angulata due to the lack of available sufficiently selected lines. In this study, a complete 3 &amp;times; 3 diallel cross was established between the normal (N), golden (G), and black (B) shell lines of C. angulata. The growth (shell height and living weight) and survival of three purebred groups and six hybrid groups under three environments (Luoyu, Jiangkou, and Houhai) were comprehensively evaluated during the larval and grow-out stages. The general combining ability (GCA) of the parental lines and the specific combining ability (SCA) of the hybrid groups were also estimated. The shell heights of the hybrid groups were significantly lower than those of their parental groups on day 25, exhibiting negative heterosis (MPH: &amp;minus;13.01 to &amp;minus;1.45; HPH: &amp;minus;16.69 to &amp;minus;5.76). Meanwhile, the survival rates of the hybrids were significantly higher than those of the parental groups. A negative value of SCA was recorded for NG (N&amp;#9792; &amp;times; G&amp;#9794;) (&amp;minus;0.031), which was in line with its lower survival rate on day 25. Significant heterosis was observed in the growth and survival of each hybrid group during the grow-out stage. The shell height and living weight of the hybrid groups were significantly higher in Houhai than in Luoyu and Jiangkou, but the survival rate in Houhai was significantly lower than in the other two sites. BG (B&amp;#9792; &amp;times; G&amp;#9794;) and GB (G&amp;#9792; &amp;times; B&amp;#9794;) had higher SCA values than the other four groups, which was consistent with their superior traits. The heterosis of shell height, living weight, and survival rate of BG was significantly greater than in the other five hybrid groups, which could be used as potential parents for breeding high-quality diploid and triploid Fujian oysters. This study demonstrated that the traits of C. angulata could be significantly improved by crossing between different selected lines, providing a reference for evaluating the utilization value of non-additive genetic effects (heterosis) between selected lines in bivalves. ]]></content:encoded> <dc:title>A Comparative Analysis of Growth, Survival, and Combining Ability Based on Diallel Crosses Among Three Selected Lines of the Fujian Oyster Crassostrea angulata with Normal, Golden, and Black Shell Colors</dc:title> <dc:creator>Yuanxin Liang</dc:creator> <dc:creator>Hong Hu</dc:creator> <dc:creator>Zhenzong Pan</dc:creator> <dc:creator>Chengxun Xu</dc:creator> <dc:creator>Qi Li</dc:creator> <dc:identifier>doi: 10.3390/jmse13020281</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>281</prism:startingPage> <prism:doi>10.3390/jmse13020281</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/281</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/280"> <title>JMSE, Vol. 13, Pages 280: The Impact of Ekman Pumping and Transport on Dosidicus gigas (Jumbo Flying Squid) Fishing Ground by Chinese Jiggers off the Coast of Peru</title> <link>https://www.mdpi.com/2077-1312/13/2/280</link> <description>Upwelling is often associated with high productivity, biodiversity, and fishery resource abundance. This study employed a generalized additive model (GAM) to analyze the effects of Ekman pumping and transport on the abundance and distribution of jumbo flying squid (Dosidicus gigas) using wind field data and Chinese commercial fishing catch data off Peru from 2012 to 2020. The results indicate that the spatial distribution of Ekman pumping and transport exhibited significant monthly variation and exerted a considerable impact on the abundance and distribution of D. gigas. Ekman pumping fluctuated between 4.98 &amp;times; 10&amp;minus;9 to 6.84 &amp;times; 10&amp;minus;7 m/s, with the strongest upwelling effects observed from February to March and October to December. Ekman transport varied from 0.89 to 2.56 m3/s and peaked in August. The GAM results indicate that the catch per unit effort (CPUE) of D. gigas was significantly affected by Ekman pumping, while the latitudinal gravity centers (LATG) of D. gigas were significantly influenced by Ekman transport and chlorophyll-a concentration (Chl-a). Both hydrodynamic processes had a significant influence on Chl-a. Ekman pumping contributed greatly to upwelling formation, significantly increasing Chl-a concentration in the northern region, while strong Ekman transport pushed high-Chl-a coastal waters offshore in the central and southern regions when Ekman pumping was weaker, resulting in increasing offshore Chl-a concentrations. Furthermore, Chl-a concentration was significantly positively correlated with Ekman pumping after a two-month lag. An El Ni&amp;ntilde;o weakened the intensity of Ekman pumping, leading to notable declines in Chl-a concentration and D. gigas CPUE. These findings demonstrate that Ekman pumping and transport significantly influence the distribution of Chl-a, to which D. gigas is sensitive, influencing the abundance and distribution of this species off the coast of Peru.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 280: The Impact of Ekman Pumping and Transport on Dosidicus gigas (Jumbo Flying Squid) Fishing Ground by Chinese Jiggers off the Coast of Peru Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/280">doi: 10.3390/jmse13020280</a> Authors: Xingnan Fang Xin Zhang Xinjun Chen Wei Yu Upwelling is often associated with high productivity, biodiversity, and fishery resource abundance. This study employed a generalized additive model (GAM) to analyze the effects of Ekman pumping and transport on the abundance and distribution of jumbo flying squid (Dosidicus gigas) using wind field data and Chinese commercial fishing catch data off Peru from 2012 to 2020. The results indicate that the spatial distribution of Ekman pumping and transport exhibited significant monthly variation and exerted a considerable impact on the abundance and distribution of D. gigas. Ekman pumping fluctuated between 4.98 &amp;times; 10&amp;minus;9 to 6.84 &amp;times; 10&amp;minus;7 m/s, with the strongest upwelling effects observed from February to March and October to December. Ekman transport varied from 0.89 to 2.56 m3/s and peaked in August. The GAM results indicate that the catch per unit effort (CPUE) of D. gigas was significantly affected by Ekman pumping, while the latitudinal gravity centers (LATG) of D. gigas were significantly influenced by Ekman transport and chlorophyll-a concentration (Chl-a). Both hydrodynamic processes had a significant influence on Chl-a. Ekman pumping contributed greatly to upwelling formation, significantly increasing Chl-a concentration in the northern region, while strong Ekman transport pushed high-Chl-a coastal waters offshore in the central and southern regions when Ekman pumping was weaker, resulting in increasing offshore Chl-a concentrations. Furthermore, Chl-a concentration was significantly positively correlated with Ekman pumping after a two-month lag. An El Ni&amp;ntilde;o weakened the intensity of Ekman pumping, leading to notable declines in Chl-a concentration and D. gigas CPUE. These findings demonstrate that Ekman pumping and transport significantly influence the distribution of Chl-a, to which D. gigas is sensitive, influencing the abundance and distribution of this species off the coast of Peru. ]]></content:encoded> <dc:title>The Impact of Ekman Pumping and Transport on Dosidicus gigas (Jumbo Flying Squid) Fishing Ground by Chinese Jiggers off the Coast of Peru</dc:title> <dc:creator>Xingnan Fang</dc:creator> <dc:creator>Xin Zhang</dc:creator> <dc:creator>Xinjun Chen</dc:creator> <dc:creator>Wei Yu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020280</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>280</prism:startingPage> <prism:doi>10.3390/jmse13020280</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/280</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/278"> <title>JMSE, Vol. 13, Pages 278: Enhancing Underwater Acoustic Target Recognition Through Advanced Feature Fusion and Deep Learning</title> <link>https://www.mdpi.com/2077-1312/13/2/278</link> <description>Underwater Acoustic Target Recognition (UATR) is critical to maritime traffic management and ocean monitoring. However, underwater acoustic analysis is fraught with difficulties. The underwater environment is highly complex, with ambient noise, variable water conditions (such as temperature and salinity), and multi-path propagation of acoustic signals. These factors make it challenging to accurately acquire and analyze target features. Traditional UATR methods struggle with feature fusion representations and model generalization. This study introduces a novel high-dimensional feature fusion method, CM3F, grounded in signal analysis and brain-like features, and integrates it with the Boundary-Aware Hybrid Transformer Network (BAHTNet), a deep-learning architecture tailored for UATR. BAHTNet comprises CBCARM and XCAT modules, leveraging a Kan network for classification and a large-margin aware focal (LMF) loss function for predictive losses. Experimental results on real-world datasets demonstrate the model&amp;rsquo;s robust generalization capabilities, achieving 99.8% accuracy on the ShipsEar dataset and 94.57% accuracy on the Deepship dataset. These findings underscore the potential of BAHTNet to significantly improve UATR performance.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 278: Enhancing Underwater Acoustic Target Recognition Through Advanced Feature Fusion and Deep Learning Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/278">doi: 10.3390/jmse13020278</a> Authors: Yanghong Zhao Guohao Xie Haoyu Chen Mingsong Chen Li Huang Underwater Acoustic Target Recognition (UATR) is critical to maritime traffic management and ocean monitoring. However, underwater acoustic analysis is fraught with difficulties. The underwater environment is highly complex, with ambient noise, variable water conditions (such as temperature and salinity), and multi-path propagation of acoustic signals. These factors make it challenging to accurately acquire and analyze target features. Traditional UATR methods struggle with feature fusion representations and model generalization. This study introduces a novel high-dimensional feature fusion method, CM3F, grounded in signal analysis and brain-like features, and integrates it with the Boundary-Aware Hybrid Transformer Network (BAHTNet), a deep-learning architecture tailored for UATR. BAHTNet comprises CBCARM and XCAT modules, leveraging a Kan network for classification and a large-margin aware focal (LMF) loss function for predictive losses. Experimental results on real-world datasets demonstrate the model&amp;rsquo;s robust generalization capabilities, achieving 99.8% accuracy on the ShipsEar dataset and 94.57% accuracy on the Deepship dataset. These findings underscore the potential of BAHTNet to significantly improve UATR performance. ]]></content:encoded> <dc:title>Enhancing Underwater Acoustic Target Recognition Through Advanced Feature Fusion and Deep Learning</dc:title> <dc:creator>Yanghong Zhao</dc:creator> <dc:creator>Guohao Xie</dc:creator> <dc:creator>Haoyu Chen</dc:creator> <dc:creator>Mingsong Chen</dc:creator> <dc:creator>Li Huang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020278</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>278</prism:startingPage> <prism:doi>10.3390/jmse13020278</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/278</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/279"> <title>JMSE, Vol. 13, Pages 279: Innovations in Wave Energy: A Case Study of TALOS-WEC&rsquo;s Multi-Axis Technology</title> <link>https://www.mdpi.com/2077-1312/13/2/279</link> <description>The technologically advanced learning ocean system&amp;mdash;wave energy converter (TALOS-WEC) project addresses the urgent need for sustainable and efficient energy solutions by leveraging the vast potential of wave energy. This project presents a pioneering approach to wave energy capture through its unique multi-axis and omnidirectional point absorber design. Featuring a fully enclosed power take-off (PTO) system, the TALOS-WEC harnesses energy across six degrees of freedom (DoFs) using an innovative internal reaction mass (IRM) mechanism. This configuration enables efficient energy extraction from the relative motion between the IRM and the hull, aiming for energy conversion efficiencies ranging between 75&amp;ndash;80% under optimal conditions, while ensuring enhanced durability in harsh marine environments. The system&amp;rsquo;s adaptability is reflected in its versatile geometric configurations, including triangular, octagonal, and circular designs, customised for diverse marine conditions. Developed at Lancaster University, UK, and supported by international collaborations, the TALOS-WEC project emphasises cutting-edge advancements in hydrodynamic modelling, geometric optimisation, and control systems. Computational methodologies leverage hybrid frequency-time domain models and advanced panel codes (WAMIT, HAMS, and NEMOH) to address non-linearities in the PTO system, ensuring precise simulations and optimal performance. Structured work packages (WPs) guide the project, addressing critical aspects such as energy capture optimisation, reliability enhancement, and cost-effectiveness through innovative monitoring and control strategies. This paper provides a comprehensive overview of the TALOS-WEC, detailing its conceptual design, development, and validation. Findings demonstrate TALOS&amp;rsquo;s potential to achieve scalable, efficient, and robust wave energy conversion, contributing to the broader advancement of renewable energy technologies. The results underscore the TALOS-WEC&amp;rsquo;s role as a cutting-edge solution for harnessing oceanic energy resources, offering perspectives into its commercial viability and future scalability.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 279: Innovations in Wave Energy: A Case Study of TALOS-WEC&rsquo;s Multi-Axis Technology Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/279">doi: 10.3390/jmse13020279</a> Authors: Fatemeh Nasr Esfahani Wanan Sheng Xiandong Ma Carrie M. Hall George Aggidis The technologically advanced learning ocean system&amp;mdash;wave energy converter (TALOS-WEC) project addresses the urgent need for sustainable and efficient energy solutions by leveraging the vast potential of wave energy. This project presents a pioneering approach to wave energy capture through its unique multi-axis and omnidirectional point absorber design. Featuring a fully enclosed power take-off (PTO) system, the TALOS-WEC harnesses energy across six degrees of freedom (DoFs) using an innovative internal reaction mass (IRM) mechanism. This configuration enables efficient energy extraction from the relative motion between the IRM and the hull, aiming for energy conversion efficiencies ranging between 75&amp;ndash;80% under optimal conditions, while ensuring enhanced durability in harsh marine environments. The system&amp;rsquo;s adaptability is reflected in its versatile geometric configurations, including triangular, octagonal, and circular designs, customised for diverse marine conditions. Developed at Lancaster University, UK, and supported by international collaborations, the TALOS-WEC project emphasises cutting-edge advancements in hydrodynamic modelling, geometric optimisation, and control systems. Computational methodologies leverage hybrid frequency-time domain models and advanced panel codes (WAMIT, HAMS, and NEMOH) to address non-linearities in the PTO system, ensuring precise simulations and optimal performance. Structured work packages (WPs) guide the project, addressing critical aspects such as energy capture optimisation, reliability enhancement, and cost-effectiveness through innovative monitoring and control strategies. This paper provides a comprehensive overview of the TALOS-WEC, detailing its conceptual design, development, and validation. Findings demonstrate TALOS&amp;rsquo;s potential to achieve scalable, efficient, and robust wave energy conversion, contributing to the broader advancement of renewable energy technologies. The results underscore the TALOS-WEC&amp;rsquo;s role as a cutting-edge solution for harnessing oceanic energy resources, offering perspectives into its commercial viability and future scalability. ]]></content:encoded> <dc:title>Innovations in Wave Energy: A Case Study of TALOS-WEC&amp;rsquo;s Multi-Axis Technology</dc:title> <dc:creator>Fatemeh Nasr Esfahani</dc:creator> <dc:creator>Wanan Sheng</dc:creator> <dc:creator>Xiandong Ma</dc:creator> <dc:creator>Carrie M. Hall</dc:creator> <dc:creator>George Aggidis</dc:creator> <dc:identifier>doi: 10.3390/jmse13020279</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Review</prism:section> <prism:startingPage>279</prism:startingPage> <prism:doi>10.3390/jmse13020279</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/279</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/277"> <title>JMSE, Vol. 13, Pages 277: Quantitative Real-Time Polymerase Chain Reaction (PCR) Assay for Rapid Monitoring of the Harmful Algal Bloom Species Cochlodinium polykrikoides</title> <link>https://www.mdpi.com/2077-1312/13/2/277</link> <description>Harmful blooms of the dinoflagellate Cochlodinium polykrikoides (Margalefidinium polykrikoides) had detrimental aquacultural and economic effects globally, and to reduce the damage caused by these blooms, early biomonitoring and quantitative analysis of C. polykrikoides are of the utmost importance. Here, for the detection of C. polykrikoides using quantitative real-time polymerase chain reactions, we developed specific primers targeting the large subunit ribosomal DNA (LSU rDNA) and evaluated their applicability in the field during the occurrence of a C. polykrikoides bloom. The specific primers not only accurately detected C. polykirkoides but also had a detection performance comparable with that obtained using microscopic observations. Accordingly, we developed a system that can be used in the field and applied when red tides occur, with accurate results being obtained more than five times more rapidly than those obtained based on microscopic analysis. Collectively, our findings indicate that the C. polykrikoides bloom detection system developed in this study can be applied to rapidly detect and accurately quantify C. polykrikoides in environmental samples. Data obtained using this system could be used as a basis for developing prompt monitoring and warning systems for the early detection of C. polykrikoides blooms in the field.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 277: Quantitative Real-Time Polymerase Chain Reaction (PCR) Assay for Rapid Monitoring of the Harmful Algal Bloom Species Cochlodinium polykrikoides Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/277">doi: 10.3390/jmse13020277</a> Authors: Min-Jeong Kim Hyun-Jung Kim Joon Sang Park Donhyug Kang Sungho Cho Hansoo Kim Seung Ho Baek Jordan Jun Chul Park Jeonghoon Han Kang Eun Kim Seung Won Jung Harmful blooms of the dinoflagellate Cochlodinium polykrikoides (Margalefidinium polykrikoides) had detrimental aquacultural and economic effects globally, and to reduce the damage caused by these blooms, early biomonitoring and quantitative analysis of C. polykrikoides are of the utmost importance. Here, for the detection of C. polykrikoides using quantitative real-time polymerase chain reactions, we developed specific primers targeting the large subunit ribosomal DNA (LSU rDNA) and evaluated their applicability in the field during the occurrence of a C. polykrikoides bloom. The specific primers not only accurately detected C. polykirkoides but also had a detection performance comparable with that obtained using microscopic observations. Accordingly, we developed a system that can be used in the field and applied when red tides occur, with accurate results being obtained more than five times more rapidly than those obtained based on microscopic analysis. Collectively, our findings indicate that the C. polykrikoides bloom detection system developed in this study can be applied to rapidly detect and accurately quantify C. polykrikoides in environmental samples. Data obtained using this system could be used as a basis for developing prompt monitoring and warning systems for the early detection of C. polykrikoides blooms in the field. ]]></content:encoded> <dc:title>Quantitative Real-Time Polymerase Chain Reaction (PCR) Assay for Rapid Monitoring of the Harmful Algal Bloom Species Cochlodinium polykrikoides</dc:title> <dc:creator>Min-Jeong Kim</dc:creator> <dc:creator>Hyun-Jung Kim</dc:creator> <dc:creator>Joon Sang Park</dc:creator> <dc:creator>Donhyug Kang</dc:creator> <dc:creator>Sungho Cho</dc:creator> <dc:creator>Hansoo Kim</dc:creator> <dc:creator>Seung Ho Baek</dc:creator> <dc:creator>Jordan Jun Chul Park</dc:creator> <dc:creator>Jeonghoon Han</dc:creator> <dc:creator>Kang Eun Kim</dc:creator> <dc:creator>Seung Won Jung</dc:creator> <dc:identifier>doi: 10.3390/jmse13020277</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>277</prism:startingPage> <prism:doi>10.3390/jmse13020277</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/277</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/276"> <title>JMSE, Vol. 13, Pages 276: System Identification and Navigation of an Underactuated Underwater Vehicle Based on LSTM</title> <link>https://www.mdpi.com/2077-1312/13/2/276</link> <description>Modeling and system identification are critical for the design, simulation, and navigation of underwater vehicles. This study presents a six degree-of-freedom (DoF) nonlinear model for a finless underactuated underwater vehicle, incorporating port-starboard symmetry and cross-flow terms. Then, hydrodynamic damping parameters are identified using an optimized Extended Kalman Filter (EKF), establishing a steady validation framework for computational fluid dynamics (CFD) simulation coefficients. Additionally, system identification is further enhanced with a Long Short-Term Memory (LSTM) neural network and a comprehensive dataset construction method, enabling time-series predictions of linear and angular velocities. To mitigate position divergence in dead reckoning (DR) caused by LSTM, a Nonlinear Explicit Complementary Filter (NECF) is integrated for attitude estimation, providing accurate yaw computation and reliable localization without dependence on acoustic sensors or machine vision. Finally, validation and evaluation are conducted to demonstrate model accuracy, EKF convergence, and the reliability of LSTM-based navigation.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 276: System Identification and Navigation of an Underactuated Underwater Vehicle Based on LSTM Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/276">doi: 10.3390/jmse13020276</a> Authors: Changhao Li Zetao Hu Desheng Zhang Xin Wang Modeling and system identification are critical for the design, simulation, and navigation of underwater vehicles. This study presents a six degree-of-freedom (DoF) nonlinear model for a finless underactuated underwater vehicle, incorporating port-starboard symmetry and cross-flow terms. Then, hydrodynamic damping parameters are identified using an optimized Extended Kalman Filter (EKF), establishing a steady validation framework for computational fluid dynamics (CFD) simulation coefficients. Additionally, system identification is further enhanced with a Long Short-Term Memory (LSTM) neural network and a comprehensive dataset construction method, enabling time-series predictions of linear and angular velocities. To mitigate position divergence in dead reckoning (DR) caused by LSTM, a Nonlinear Explicit Complementary Filter (NECF) is integrated for attitude estimation, providing accurate yaw computation and reliable localization without dependence on acoustic sensors or machine vision. Finally, validation and evaluation are conducted to demonstrate model accuracy, EKF convergence, and the reliability of LSTM-based navigation. ]]></content:encoded> <dc:title>System Identification and Navigation of an Underactuated Underwater Vehicle Based on LSTM</dc:title> <dc:creator>Changhao Li</dc:creator> <dc:creator>Zetao Hu</dc:creator> <dc:creator>Desheng Zhang</dc:creator> <dc:creator>Xin Wang</dc:creator> <dc:identifier>doi: 10.3390/jmse13020276</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>276</prism:startingPage> <prism:doi>10.3390/jmse13020276</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/276</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/275"> <title>JMSE, Vol. 13, Pages 275: Numerical Simulation Study of the Motion Characteristics of Autonomous Underwater Vehicles During Mooring Lurking Procedure</title> <link>https://www.mdpi.com/2077-1312/13/2/275</link> <description>A two-dimensional coupled dynamics model for a moored autonomous underwater vehicle (AUV) was developed using the lumped mass method for mooring cable dynamics and the Newton-Euler method for rigid body dynamics. This model enables the integrated simulation of AUV motion, flow field interactions, and mooring cable behavior. The study investigates the effects of varying ocean current velocities and mooring cable lengths on AUV motion responses. The results indicate that under the influence of mooring forces, the AUV stabilizes near its equilibrium position after release and undergoes periodic oscillatory motion. Specifically, when the X-direction oscillation completes two cycles and the Y-direction oscillation completes four cycles, the AUV demonstrates an 8-shaped trajectory, with maximum motion amplitudes observed. These findings provide insights into the dynamic behavior of moored AUVs in ocean environments, contributing to the design and operation of long-term underwater monitoring systems.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 275: Numerical Simulation Study of the Motion Characteristics of Autonomous Underwater Vehicles During Mooring Lurking Procedure Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/275">doi: 10.3390/jmse13020275</a> Authors: Yuyang Hu Zhaoyong Mao Bo Cheng Bo Li Wenlong Tian A two-dimensional coupled dynamics model for a moored autonomous underwater vehicle (AUV) was developed using the lumped mass method for mooring cable dynamics and the Newton-Euler method for rigid body dynamics. This model enables the integrated simulation of AUV motion, flow field interactions, and mooring cable behavior. The study investigates the effects of varying ocean current velocities and mooring cable lengths on AUV motion responses. The results indicate that under the influence of mooring forces, the AUV stabilizes near its equilibrium position after release and undergoes periodic oscillatory motion. Specifically, when the X-direction oscillation completes two cycles and the Y-direction oscillation completes four cycles, the AUV demonstrates an 8-shaped trajectory, with maximum motion amplitudes observed. These findings provide insights into the dynamic behavior of moored AUVs in ocean environments, contributing to the design and operation of long-term underwater monitoring systems. ]]></content:encoded> <dc:title>Numerical Simulation Study of the Motion Characteristics of Autonomous Underwater Vehicles During Mooring Lurking Procedure</dc:title> <dc:creator>Yuyang Hu</dc:creator> <dc:creator>Zhaoyong Mao</dc:creator> <dc:creator>Bo Cheng</dc:creator> <dc:creator>Bo Li</dc:creator> <dc:creator>Wenlong Tian</dc:creator> <dc:identifier>doi: 10.3390/jmse13020275</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>275</prism:startingPage> <prism:doi>10.3390/jmse13020275</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/275</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/272"> <title>JMSE, Vol. 13, Pages 272: Enhanced MILP Approach for Long-Term Multi-Vessel Maritime Inventory Routing with Application to Antarctic Logistics</title> <link>https://www.mdpi.com/2077-1312/13/2/272</link> <description>The maritime inventory routing problem (MIRP) integrates vessel routing and inventory management over a planning horizon to optimize logistical operations in marine environments. While existing models predominantly address short-term planning with single vessels, this research advances the field by presenting a tightened mixed-integer linear programming (MILP) model designed for long-term planning with multiple vessels. The proposed model leverages an improved mathematical formulation and state-of-the-art optimization solvers to enhance computational performance. To demonstrate its applicability, the model was evaluated using benchmark instances from the literature and new instances derived from the logistics of Chilean scientific bases in Antarctica, a challenging and underexplored maritime environment. The results show computational time reductions of up to 98% for small to medium-sized instances, achieved through the incorporation of valid inequalities into the model and the use of advanced hardware and solvers. For larger instances, optimal or near-optimal solutions were achieved within one hour for a planning horizon of 60 time units, with optimality gaps below 24.7% for a 120-time-unit horizon. These findings highlight the potential of the model to support decision-making in complex maritime logistics scenarios, extending its application to long-term, multi-vessel operations in remote and environmentally sensitive regions. The proposed framework provides a valuable tool for enhancing the sustainability and efficiency of maritime logistics systems.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 272: Enhanced MILP Approach for Long-Term Multi-Vessel Maritime Inventory Routing with Application to Antarctic Logistics Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/272">doi: 10.3390/jmse13020272</a> Authors: Dagoberto Cifuentes-Lobos Lorena Pradenas Victor Parada The maritime inventory routing problem (MIRP) integrates vessel routing and inventory management over a planning horizon to optimize logistical operations in marine environments. While existing models predominantly address short-term planning with single vessels, this research advances the field by presenting a tightened mixed-integer linear programming (MILP) model designed for long-term planning with multiple vessels. The proposed model leverages an improved mathematical formulation and state-of-the-art optimization solvers to enhance computational performance. To demonstrate its applicability, the model was evaluated using benchmark instances from the literature and new instances derived from the logistics of Chilean scientific bases in Antarctica, a challenging and underexplored maritime environment. The results show computational time reductions of up to 98% for small to medium-sized instances, achieved through the incorporation of valid inequalities into the model and the use of advanced hardware and solvers. For larger instances, optimal or near-optimal solutions were achieved within one hour for a planning horizon of 60 time units, with optimality gaps below 24.7% for a 120-time-unit horizon. These findings highlight the potential of the model to support decision-making in complex maritime logistics scenarios, extending its application to long-term, multi-vessel operations in remote and environmentally sensitive regions. The proposed framework provides a valuable tool for enhancing the sustainability and efficiency of maritime logistics systems. ]]></content:encoded> <dc:title>Enhanced MILP Approach for Long-Term Multi-Vessel Maritime Inventory Routing with Application to Antarctic Logistics</dc:title> <dc:creator>Dagoberto Cifuentes-Lobos</dc:creator> <dc:creator>Lorena Pradenas</dc:creator> <dc:creator>Victor Parada</dc:creator> <dc:identifier>doi: 10.3390/jmse13020272</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>272</prism:startingPage> <prism:doi>10.3390/jmse13020272</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/272</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/273"> <title>JMSE, Vol. 13, Pages 273: Coupled Aerodynamic&ndash;Hydrodynamic Analysis of Spar-Type Floating Foundations with Normal and Lightweight Concrete for Offshore Wind Energy in Colombia</title> <link>https://www.mdpi.com/2077-1312/13/2/273</link> <description>Foundations for offshore wind turbines come in various types, with spar-type floating foundations being the most promising for different depths. This research analyzed the hydrodynamic&amp;ndash;mechanical response of a 5 MW spar-type floating foundation under conditions typical of the Colombian Caribbean following the DNV standard. Two types of concrete were evaluated through numerical modeling: one with normal density (2400 kg/m3) and another with lightweight density (1900 kg/m3). Based on the hydrodynamic and structural dynamic response, it was concluded that the variation in concrete density only affected pitch rotation, with better performance observed in the lightweight concrete, achieving maximum rotations of 10&amp;deg;. The coupled model between QBlade and Aqwa was validated by code-to-code comparisons with QBlade&amp;rsquo;s fully coupled system with its ocean module. This study contributes to offshore engineering in Colombia by providing a detailed methodology for developing a coupled simulation, serving as a reference for both academia and industry amid the ongoing and projected wind energy development initiatives in the country.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 273: Coupled Aerodynamic&ndash;Hydrodynamic Analysis of Spar-Type Floating Foundations with Normal and Lightweight Concrete for Offshore Wind Energy in Colombia Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/273">doi: 10.3390/jmse13020273</a> Authors: Jose Calder贸n Andr茅s Guzm谩n William G贸mez Foundations for offshore wind turbines come in various types, with spar-type floating foundations being the most promising for different depths. This research analyzed the hydrodynamic&amp;ndash;mechanical response of a 5 MW spar-type floating foundation under conditions typical of the Colombian Caribbean following the DNV standard. Two types of concrete were evaluated through numerical modeling: one with normal density (2400 kg/m3) and another with lightweight density (1900 kg/m3). Based on the hydrodynamic and structural dynamic response, it was concluded that the variation in concrete density only affected pitch rotation, with better performance observed in the lightweight concrete, achieving maximum rotations of 10&amp;deg;. The coupled model between QBlade and Aqwa was validated by code-to-code comparisons with QBlade&amp;rsquo;s fully coupled system with its ocean module. This study contributes to offshore engineering in Colombia by providing a detailed methodology for developing a coupled simulation, serving as a reference for both academia and industry amid the ongoing and projected wind energy development initiatives in the country. ]]></content:encoded> <dc:title>Coupled Aerodynamic&amp;ndash;Hydrodynamic Analysis of Spar-Type Floating Foundations with Normal and Lightweight Concrete for Offshore Wind Energy in Colombia</dc:title> <dc:creator>Jose Calder贸n</dc:creator> <dc:creator>Andr茅s Guzm谩n</dc:creator> <dc:creator>William G贸mez</dc:creator> <dc:identifier>doi: 10.3390/jmse13020273</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>273</prism:startingPage> <prism:doi>10.3390/jmse13020273</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/273</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/271"> <title>JMSE, Vol. 13, Pages 271: Effects of Oxygen Enrichment and Air Humidification on the Combustion and Emissions of the Biodiesel Marine Diesel Engine</title> <link>https://www.mdpi.com/2077-1312/13/2/271</link> <description>With increasingly strict emission regulations, research on diesel engine combustion and emissions is urgently needed. This study conducted computational fluid dynamics modeling on diesel engines. The effects of intake humidity and oxygen concentration of a diesel engine on the combustion emission of biodiesel were studied. The results indicate that when the humidity ratio is below 0.4 (WR = 0.4), intake humidification has a certain promoting effect on the combustion reaction process. Water molecule pyrolysis can promote the pyrolysis of biodiesel, and the peak pressure in the cylinder slightly increases. As the intake humidification ratio increases, the cylinder temperature decreases, and the oxygen concentration also decreases due to the increase in water molecular weight. The combustion reaction process is suppressed, and the cylinder pressure decreases. When the humidity ratio is 1 (WR = 1), the peak pressure decreases by 2.61% compared to when it is not humidified (WR = 0). The concentration of O radicals decreases with an increase in humidity ratio. When WR = 1.0, the emissions of NOx decreased by 55.02%, but with the decrease in oxygen concentration in the high-temperature area, the emissions of soot increased. The results indicate that as the oxygen concentration increases, the cylinder pressure and average temperature increase, the ignition-delay time decreases, the heat-release rate increases, and it ultimately leads to an increase in NOx emissions.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 271: Effects of Oxygen Enrichment and Air Humidification on the Combustion and Emissions of the Biodiesel Marine Diesel Engine Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/271">doi: 10.3390/jmse13020271</a> Authors: Peng Geng Xiong Hu Xiaohu Lin With increasingly strict emission regulations, research on diesel engine combustion and emissions is urgently needed. This study conducted computational fluid dynamics modeling on diesel engines. The effects of intake humidity and oxygen concentration of a diesel engine on the combustion emission of biodiesel were studied. The results indicate that when the humidity ratio is below 0.4 (WR = 0.4), intake humidification has a certain promoting effect on the combustion reaction process. Water molecule pyrolysis can promote the pyrolysis of biodiesel, and the peak pressure in the cylinder slightly increases. As the intake humidification ratio increases, the cylinder temperature decreases, and the oxygen concentration also decreases due to the increase in water molecular weight. The combustion reaction process is suppressed, and the cylinder pressure decreases. When the humidity ratio is 1 (WR = 1), the peak pressure decreases by 2.61% compared to when it is not humidified (WR = 0). The concentration of O radicals decreases with an increase in humidity ratio. When WR = 1.0, the emissions of NOx decreased by 55.02%, but with the decrease in oxygen concentration in the high-temperature area, the emissions of soot increased. The results indicate that as the oxygen concentration increases, the cylinder pressure and average temperature increase, the ignition-delay time decreases, the heat-release rate increases, and it ultimately leads to an increase in NOx emissions. ]]></content:encoded> <dc:title>Effects of Oxygen Enrichment and Air Humidification on the Combustion and Emissions of the Biodiesel Marine Diesel Engine</dc:title> <dc:creator>Peng Geng</dc:creator> <dc:creator>Xiong Hu</dc:creator> <dc:creator>Xiaohu Lin</dc:creator> <dc:identifier>doi: 10.3390/jmse13020271</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>271</prism:startingPage> <prism:doi>10.3390/jmse13020271</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/271</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/274"> <title>JMSE, Vol. 13, Pages 274: Inlet Passage Hydraulic Performance Optimization of Coastal Drainage Pump System Based on Machine Learning Algorithms</title> <link>https://www.mdpi.com/2077-1312/13/2/274</link> <description>The axial-flow pump system has been widely applied to coastal drainage pump stations, but the hydraulic performance optimization based on the contraction angles of the inlet passage has not been studied. This paper combined the computational fluid dynamics (CFD) method, machine learning (ML) algorithms and genetic algorithm (GA) to find the optimal contraction angles of the inlet passage. The 125 sets of comprehensive objective function were obtained by the CFD method. Three contraction angles and comprehensive objective function values were regressed by three ML algorithms. After hyperparameter optimization, the Gaussian process regression (GPR) model had the highest R2 = 0.958 in the test set and had the strongest generalization ability among the three models. The impact degree of the three contraction angles on the objective function of the GPR model was investigated by the Sobol sensitivity analysis method; the results indicated that the order of impact degree from high to low was &amp;theta;3&amp;gt;&amp;theta;2&amp;gt;&amp;theta;1. The optimal objective function values of the GPR model and corresponding contraction angles were searched through GA; the maximum objective function value was 0.963 and corresponding contraction angles were &amp;theta;1=13.34&amp;deg;, &amp;theta;2=28.36&amp;deg; and &amp;theta;3=3.64&amp;deg;, respectively. The results of this study can provide reference for the optimization of inlet passages in coastal drainage pump systems.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 274: Inlet Passage Hydraulic Performance Optimization of Coastal Drainage Pump System Based on Machine Learning Algorithms Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/274">doi: 10.3390/jmse13020274</a> Authors: Tao Jiang Weigang Lu Linguang Lu Lei Xu Wang Xi Jianfeng Liu Ye Zhu The axial-flow pump system has been widely applied to coastal drainage pump stations, but the hydraulic performance optimization based on the contraction angles of the inlet passage has not been studied. This paper combined the computational fluid dynamics (CFD) method, machine learning (ML) algorithms and genetic algorithm (GA) to find the optimal contraction angles of the inlet passage. The 125 sets of comprehensive objective function were obtained by the CFD method. Three contraction angles and comprehensive objective function values were regressed by three ML algorithms. After hyperparameter optimization, the Gaussian process regression (GPR) model had the highest R2 = 0.958 in the test set and had the strongest generalization ability among the three models. The impact degree of the three contraction angles on the objective function of the GPR model was investigated by the Sobol sensitivity analysis method; the results indicated that the order of impact degree from high to low was &amp;theta;3&amp;gt;&amp;theta;2&amp;gt;&amp;theta;1. The optimal objective function values of the GPR model and corresponding contraction angles were searched through GA; the maximum objective function value was 0.963 and corresponding contraction angles were &amp;theta;1=13.34&amp;deg;, &amp;theta;2=28.36&amp;deg; and &amp;theta;3=3.64&amp;deg;, respectively. The results of this study can provide reference for the optimization of inlet passages in coastal drainage pump systems. ]]></content:encoded> <dc:title>Inlet Passage Hydraulic Performance Optimization of Coastal Drainage Pump System Based on Machine Learning Algorithms</dc:title> <dc:creator>Tao Jiang</dc:creator> <dc:creator>Weigang Lu</dc:creator> <dc:creator>Linguang Lu</dc:creator> <dc:creator>Lei Xu</dc:creator> <dc:creator>Wang Xi</dc:creator> <dc:creator>Jianfeng Liu</dc:creator> <dc:creator>Ye Zhu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020274</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>274</prism:startingPage> <prism:doi>10.3390/jmse13020274</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/274</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/270"> <title>JMSE, Vol. 13, Pages 270: Dynamic Characteristics of Bidirectional Misaligned Marine Water-Lubricated Bearings Considering Turbulence, Surface Roughness and Bush Deformation</title> <link>https://www.mdpi.com/2077-1312/13/2/270</link> <description>The marine water-lubricated bearing&amp;rsquo;s (WLBs) dynamic properties are essential for ensuring the shaft system&amp;rsquo;s operational dependability. The coupled model of mixed lubrication and turbulence under the impact of bidirectional misalignment is proposed in this research, and the perturbation equations of marine WLBs with 32 coefficients are derived. The finite difference method (FDM) is used to solve the steady-state and perturbation equations, and the impacts of turbulence, bearing bush deformation, surface roughness, and bidirectional shaft misalignment on the dynamic characteristics of the WLBs are systematically investigated. The results reveal that under mixed lubrication, surface roughness and the turbulence effect can both greatly improve the stiffness and damping of the bearings, but that there is a threshold phenomenon for the turbulence effect&amp;rsquo;s influence on these properties. Neglecting the elastic deformation of the bush may lead to an overestimation of the bearings&amp;rsquo; stiffness and damping, causing substantial inaccuracies in conditions of heavy load or declined Young&amp;rsquo;s modulus. The 32 coefficients of the WLB exhibit considerable variation with the misalignment angle; hence, a more comprehensive dynamic model should be developed for misaligned marine WLBs. The study&amp;rsquo;s findings provide valuable insights for rotor dynamics research and optimal design of lubrication performance in marine WLBs.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 270: Dynamic Characteristics of Bidirectional Misaligned Marine Water-Lubricated Bearings Considering Turbulence, Surface Roughness and Bush Deformation Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/270">doi: 10.3390/jmse13020270</a> Authors: Ziqi Chen Ji Wang Rui Li Yujun Liu The marine water-lubricated bearing&amp;rsquo;s (WLBs) dynamic properties are essential for ensuring the shaft system&amp;rsquo;s operational dependability. The coupled model of mixed lubrication and turbulence under the impact of bidirectional misalignment is proposed in this research, and the perturbation equations of marine WLBs with 32 coefficients are derived. The finite difference method (FDM) is used to solve the steady-state and perturbation equations, and the impacts of turbulence, bearing bush deformation, surface roughness, and bidirectional shaft misalignment on the dynamic characteristics of the WLBs are systematically investigated. The results reveal that under mixed lubrication, surface roughness and the turbulence effect can both greatly improve the stiffness and damping of the bearings, but that there is a threshold phenomenon for the turbulence effect&amp;rsquo;s influence on these properties. Neglecting the elastic deformation of the bush may lead to an overestimation of the bearings&amp;rsquo; stiffness and damping, causing substantial inaccuracies in conditions of heavy load or declined Young&amp;rsquo;s modulus. The 32 coefficients of the WLB exhibit considerable variation with the misalignment angle; hence, a more comprehensive dynamic model should be developed for misaligned marine WLBs. The study&amp;rsquo;s findings provide valuable insights for rotor dynamics research and optimal design of lubrication performance in marine WLBs. ]]></content:encoded> <dc:title>Dynamic Characteristics of Bidirectional Misaligned Marine Water-Lubricated Bearings Considering Turbulence, Surface Roughness and Bush Deformation</dc:title> <dc:creator>Ziqi Chen</dc:creator> <dc:creator>Ji Wang</dc:creator> <dc:creator>Rui Li</dc:creator> <dc:creator>Yujun Liu</dc:creator> <dc:identifier>doi: 10.3390/jmse13020270</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>270</prism:startingPage> <prism:doi>10.3390/jmse13020270</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/270</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/269"> <title>JMSE, Vol. 13, Pages 269: Nonlinear Model Predictive Control Energy Management Strategy for Hybrid Power Ships Based on Working Condition Identification</title> <link>https://www.mdpi.com/2077-1312/13/2/269</link> <description>Hybrid power technology for ships is an effective way to promote the green and low-carbon development of the maritime industry. The development of pattern recognition technology provides new research ideas for the rational allocation and utilization of energy in hybrid power ships. To reduce fuel consumption, a nonlinear model predictive control energy management strategy based on working condition identification is proposed for optimal energy management to solve the problem of real-time optimal adjustment of generators and batteries. The core of the strategy is to identify the ship&amp;rsquo;s working conditions and the nonlinear model predictive control algorithm. Firstly, to achieve the working condition identification task, a ship working condition dataset based on a hybrid supply power ship data is constructed. The labeled dataset is trained using deep learning techniques. Secondly, based on the identification results, a nonlinear model predictive control algorithm is designed to adjust the generator speed and the battery current to achieve energy optimization control under constraints. Finally, the effectiveness of the proposed strategy in optimizing energy control and reducing fuel consumption is verified through simulation. The proposed strategy can reduce the generator fuel consumption by 5.5% under no noise disturbance when compared with conventional predictive control. Under 10% noise disturbance, it is still able to reduce the fuel consumption by 2.6%.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 269: Nonlinear Model Predictive Control Energy Management Strategy for Hybrid Power Ships Based on Working Condition Identification Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/269">doi: 10.3390/jmse13020269</a> Authors: Yucheng Yan Zhichao Chen Diju Gao Hybrid power technology for ships is an effective way to promote the green and low-carbon development of the maritime industry. The development of pattern recognition technology provides new research ideas for the rational allocation and utilization of energy in hybrid power ships. To reduce fuel consumption, a nonlinear model predictive control energy management strategy based on working condition identification is proposed for optimal energy management to solve the problem of real-time optimal adjustment of generators and batteries. The core of the strategy is to identify the ship&amp;rsquo;s working conditions and the nonlinear model predictive control algorithm. Firstly, to achieve the working condition identification task, a ship working condition dataset based on a hybrid supply power ship data is constructed. The labeled dataset is trained using deep learning techniques. Secondly, based on the identification results, a nonlinear model predictive control algorithm is designed to adjust the generator speed and the battery current to achieve energy optimization control under constraints. Finally, the effectiveness of the proposed strategy in optimizing energy control and reducing fuel consumption is verified through simulation. The proposed strategy can reduce the generator fuel consumption by 5.5% under no noise disturbance when compared with conventional predictive control. Under 10% noise disturbance, it is still able to reduce the fuel consumption by 2.6%. ]]></content:encoded> <dc:title>Nonlinear Model Predictive Control Energy Management Strategy for Hybrid Power Ships Based on Working Condition Identification</dc:title> <dc:creator>Yucheng Yan</dc:creator> <dc:creator>Zhichao Chen</dc:creator> <dc:creator>Diju Gao</dc:creator> <dc:identifier>doi: 10.3390/jmse13020269</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>269</prism:startingPage> <prism:doi>10.3390/jmse13020269</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/269</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/268"> <title>JMSE, Vol. 13, Pages 268: Effect of a Compression Ratio Increase and High-Flow-Rate Injection on the Combustion Characteristics of an Ammonia Direct Injection Spark-Ignited Engine</title> <link>https://www.mdpi.com/2077-1312/13/2/268</link> <description>Despite efforts to use ammonia as a fuel, there remain problems with low combustion speeds and high unburned ammonia (NH3) emissions. Therefore, methods to compensate for slow combustion speeds and stabilize combustion have been studied. This study aims to analyze how increasing the compression ratio affects engine performance to enhance thermal efficiency and reduce unburned emissions in a high-pressure ammonia direct injection spark-ignited engine. In addition, by applying a high-flow-rate (HFR) injector, an improvement in the combustion of ammonia fuel and exhaust gas emissions is observed through changes in the air&amp;ndash;fuel mixture formation of high-pressure directly injected ammonia fuel. Compared with the existing compression ratio, the incomplete combustion loss due to unburned NH3 increases significantly, and the thermal efficiency does not increase under an increased compression ratio. When HFR injectors are applied with an increase in the compression ratio, the net work increases by 4.7%, as incomplete combustion and energy losses of fuel are reduced by reducing the amount of unburned NH3.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 268: Effect of a Compression Ratio Increase and High-Flow-Rate Injection on the Combustion Characteristics of an Ammonia Direct Injection Spark-Ignited Engine Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/268">doi: 10.3390/jmse13020268</a> Authors: Cheolwoong Park Ilpum Jang Jeongwoo Lee Minki Kim Chansoo Park Yongrae Kim Young Choi Despite efforts to use ammonia as a fuel, there remain problems with low combustion speeds and high unburned ammonia (NH3) emissions. Therefore, methods to compensate for slow combustion speeds and stabilize combustion have been studied. This study aims to analyze how increasing the compression ratio affects engine performance to enhance thermal efficiency and reduce unburned emissions in a high-pressure ammonia direct injection spark-ignited engine. In addition, by applying a high-flow-rate (HFR) injector, an improvement in the combustion of ammonia fuel and exhaust gas emissions is observed through changes in the air&amp;ndash;fuel mixture formation of high-pressure directly injected ammonia fuel. Compared with the existing compression ratio, the incomplete combustion loss due to unburned NH3 increases significantly, and the thermal efficiency does not increase under an increased compression ratio. When HFR injectors are applied with an increase in the compression ratio, the net work increases by 4.7%, as incomplete combustion and energy losses of fuel are reduced by reducing the amount of unburned NH3. ]]></content:encoded> <dc:title>Effect of a Compression Ratio Increase and High-Flow-Rate Injection on the Combustion Characteristics of an Ammonia Direct Injection Spark-Ignited Engine</dc:title> <dc:creator>Cheolwoong Park</dc:creator> <dc:creator>Ilpum Jang</dc:creator> <dc:creator>Jeongwoo Lee</dc:creator> <dc:creator>Minki Kim</dc:creator> <dc:creator>Chansoo Park</dc:creator> <dc:creator>Yongrae Kim</dc:creator> <dc:creator>Young Choi</dc:creator> <dc:identifier>doi: 10.3390/jmse13020268</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>268</prism:startingPage> <prism:doi>10.3390/jmse13020268</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/268</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <item rdf:about="https://www.mdpi.com/2077-1312/13/2/267"> <title>JMSE, Vol. 13, Pages 267: Numerical Simulation on Hybrid Lifting Operation of Polymetallic Nodules and Rare-Earth Elements-Rich Mud by Air-Lift Pump in Deep Sea Around Minamitorishima Island</title> <link>https://www.mdpi.com/2077-1312/13/2/267</link> <description>Polymetallic nodules and REE-rich mud under the seabed of 5500&amp;ndash;5700 m water depth around Minamitorishima island are promising and attractive for exploration and development. Following our previous research, numerical analysis was used to investigate the unsteady flow characteristics and the lifting performance of a commercial production system using an air-lift pump for hybrid lifting, lifting both polymetallic nodules and REE-rich mud. Gas&amp;ndash;liquid&amp;ndash;solid three-phase flow and gas&amp;ndash;liquid two-phase flow in the system were analyzed using the one-dimensional drift&amp;ndash;flux model. First, the reliability of the schemes and program was verified by comparing the numerical results with the experimental ones. Next, numerical simulations were conducted, in which the model&amp;rsquo;s dimensions were related to a commercial production system operated in the deep sea around Minamitorishima island, and the conditions fit the expected production rate. The results revealed the unsteady flow characteristics under the operations, such as start-up, shut-down, feed of polymetallic nodules and REE-rich mud, and those associated with disturbances, such as feed rate fluctuations. We demonstrate that the program and the schemes can simulate the unsteady flow characteristics and the lifting performance of a commercial production system with an air-lift pump well, and they can derive useful information and know-how in advance for the safe and continuous operation of the system.</description> <pubDate>2025-01-31</pubDate> <content:encoded><![CDATA[ JMSE, Vol. 13, Pages 267: Numerical Simulation on Hybrid Lifting Operation of Polymetallic Nodules and Rare-Earth Elements-Rich Mud by Air-Lift Pump in Deep Sea Around Minamitorishima Island Journal of Marine Science and Engineering <a href="https://www.mdpi.com/2077-1312/13/2/267">doi: 10.3390/jmse13020267</a> Authors: Yoshiyuki Shimizu Masatoshi Sugihara Koichiro Fujinaga Kentaro Nakamura Yasuhiro Kato Polymetallic nodules and REE-rich mud under the seabed of 5500&amp;ndash;5700 m water depth around Minamitorishima island are promising and attractive for exploration and development. Following our previous research, numerical analysis was used to investigate the unsteady flow characteristics and the lifting performance of a commercial production system using an air-lift pump for hybrid lifting, lifting both polymetallic nodules and REE-rich mud. Gas&amp;ndash;liquid&amp;ndash;solid three-phase flow and gas&amp;ndash;liquid two-phase flow in the system were analyzed using the one-dimensional drift&amp;ndash;flux model. First, the reliability of the schemes and program was verified by comparing the numerical results with the experimental ones. Next, numerical simulations were conducted, in which the model&amp;rsquo;s dimensions were related to a commercial production system operated in the deep sea around Minamitorishima island, and the conditions fit the expected production rate. The results revealed the unsteady flow characteristics under the operations, such as start-up, shut-down, feed of polymetallic nodules and REE-rich mud, and those associated with disturbances, such as feed rate fluctuations. We demonstrate that the program and the schemes can simulate the unsteady flow characteristics and the lifting performance of a commercial production system with an air-lift pump well, and they can derive useful information and know-how in advance for the safe and continuous operation of the system. ]]></content:encoded> <dc:title>Numerical Simulation on Hybrid Lifting Operation of Polymetallic Nodules and Rare-Earth Elements-Rich Mud by Air-Lift Pump in Deep Sea Around Minamitorishima Island</dc:title> <dc:creator>Yoshiyuki Shimizu</dc:creator> <dc:creator>Masatoshi Sugihara</dc:creator> <dc:creator>Koichiro Fujinaga</dc:creator> <dc:creator>Kentaro Nakamura</dc:creator> <dc:creator>Yasuhiro Kato</dc:creator> <dc:identifier>doi: 10.3390/jmse13020267</dc:identifier> <dc:source>Journal of Marine Science and Engineering</dc:source> <dc:date>2025-01-31</dc:date> <prism:publicationName>Journal of Marine Science and Engineering</prism:publicationName> <prism:publicationDate>2025-01-31</prism:publicationDate> <prism:volume>13</prism:volume> <prism:number>2</prism:number> <prism:section>Article</prism:section> <prism:startingPage>267</prism:startingPage> <prism:doi>10.3390/jmse13020267</prism:doi> <prism:url>https://www.mdpi.com/2077-1312/13/2/267</prism:url> <cc:license rdf:resource="CC BY 4.0"/> </item> <cc:License rdf:about="https://creativecommons.org/licenses/by/4.0/"> <cc:permits rdf:resource="https://creativecommons.org/ns#Reproduction" /> <cc:permits rdf:resource="https://creativecommons.org/ns#Distribution" /> <cc:permits rdf:resource="https://creativecommons.org/ns#DerivativeWorks" /> </cc:License> </rdf:RDF>