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scattering characteristics</title> <meta name="description" content="Search results for: acoustic scattering characteristics"> <meta name="keywords" content="acoustic scattering characteristics"> <meta name="viewport" content="width=device-width, initial-scale=1, minimum-scale=1, maximum-scale=1, user-scalable=no"> <meta charset="utf-8"> <link href="https://cdn.waset.org/favicon.ico" type="image/x-icon" rel="shortcut icon"> <link href="https://cdn.waset.org/static/plugins/bootstrap-4.2.1/css/bootstrap.min.css" rel="stylesheet"> <link href="https://cdn.waset.org/static/plugins/fontawesome/css/all.min.css" rel="stylesheet"> <link href="https://cdn.waset.org/static/css/site.css?v=150220211555" rel="stylesheet"> </head> <body> <header> <div class="container"> <nav class="navbar navbar-expand-lg navbar-light"> <a class="navbar-brand" href="https://waset.org"> <img src="https://cdn.waset.org/static/images/wasetc.png" alt="Open Science Research Excellence" title="Open Science Research 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method="get" action="https://publications.waset.org/abstracts/search"> <div id="custom-search-input"> <div class="input-group"> <i class="fas fa-search"></i> <input type="text" class="search-query" name="q" placeholder="Author, Title, Abstract, Keywords" value="acoustic scattering characteristics"> <input type="submit" class="btn_search" value="Search"> </div> </div> </form> </div> </div> <div class="row mt-3"> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Commenced</strong> in January 2007</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Frequency:</strong> Monthly</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Edition:</strong> International</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Paper Count:</strong> 8161</div> </div> </div> </div> <h1 class="mt-3 mb-3 text-center" style="font-size:1.6rem;">Search results for: acoustic scattering characteristics</h1> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8161</span> Analysis Of Non-uniform Characteristics Of Small Underwater Targets Based On Clustering</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Tianyang%20Xu">Tianyang Xu</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Small underwater targets generally have a non-centrosymmetric geometry, and the acoustic scattering field of the target has spatial inhomogeneity under active sonar detection conditions. In view of the above problems, this paper takes the hemispherical cylindrical shell as the research object, and considers the angle continuity implied in the echo characteristics, and proposes a cluster-driven research method for the non-uniform characteristics of target echo angle. First, the target echo features are extracted, and feature vectors are constructed. Secondly, the t-SNE algorithm is used to improve the internal connection of the feature vector in the low-dimensional feature space and to construct the visual feature space. Finally, the implicit angular relationship between echo features is extracted under unsupervised condition by cluster analysis. The reconstruction results of the local geometric structure of the target corresponding to different categories show that the method can effectively divide the angle interval of the local structure of the target according to the natural acoustic scattering characteristics of the target. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=underwater%20target%3B" title="underwater target;">underwater target;</a>, <a href="https://publications.waset.org/abstracts/search?q=non-uniform%20characteristics%3B" title=" non-uniform characteristics;"> non-uniform characteristics;</a>, <a href="https://publications.waset.org/abstracts/search?q=cluster-driven%20method%3B" title=" cluster-driven method;"> cluster-driven method;</a>, <a href="https://publications.waset.org/abstracts/search?q=acoustic%20scattering%20characteristics" title=" acoustic scattering characteristics"> acoustic scattering characteristics</a> </p> <a href="https://publications.waset.org/abstracts/169602/analysis-of-non-uniform-characteristics-of-small-underwater-targets-based-on-clustering" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/169602.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">132</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8160</span> The Condition Testing of Damaged Plates Using Acoustic Features and Machine Learning</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Kyle%20Saltmarsh">Kyle Saltmarsh</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Acoustic testing possesses many benefits due to its non-destructive nature and practicality. There hence exists many scenarios in which using acoustic testing for condition testing shows powerful feasibility. A wealth of information is contained within the acoustic and vibration characteristics of structures, allowing the development meaningful features for the classification of their respective condition. In this paper, methods, results, and discussions are presented on the use of non-destructive acoustic testing coupled with acoustic feature extraction and machine learning techniques for the condition testing of manufactured circular steel plates subjected to varied levels of damage. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=plates" title="plates">plates</a>, <a href="https://publications.waset.org/abstracts/search?q=deformation" title=" deformation"> deformation</a>, <a href="https://publications.waset.org/abstracts/search?q=acoustic%20features" title=" acoustic features"> acoustic features</a>, <a href="https://publications.waset.org/abstracts/search?q=machine%20learning" title=" machine learning"> machine learning</a> </p> <a href="https://publications.waset.org/abstracts/76911/the-condition-testing-of-damaged-plates-using-acoustic-features-and-machine-learning" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/76911.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">337</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8159</span> The Contribution of Density Fluctuations in Ultrasound Scattering in Cancellous Bone</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=A.%20Elsariti">A. Elsariti</a>, <a href="https://publications.waset.org/abstracts/search?q=T.%20Evans"> T. Evans </a> </p> <p class="card-text"><strong>Abstract:</strong></p> An understanding of the interaction between acoustic waves and cancellous bone is needed in order to realize the full clinical potential of ultrasonic bone measurements. Scattering is likely to be of central importance but has received little attention to date. Few theoretical approaches have been described to explain scattering of ultrasound from bone. In this study, a scattering model based on velocity and density fluctuations in a binary mixture (marrow fat and cortical matrix) was used to estimate the ultrasonic attenuation in cancellous bone as a function of volume fraction. Predicted attenuation and backscatter coefficient were obtained for a range of porosities and scatterer size. At 600 kHZ and for different scatterer size the effect of velocity and density fluctuations in the predicted attenuation was approximately 60% higher than velocity fluctuations. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=ultrasound%20scattering" title="ultrasound scattering">ultrasound scattering</a>, <a href="https://publications.waset.org/abstracts/search?q=sound%20speed" title=" sound speed"> sound speed</a>, <a href="https://publications.waset.org/abstracts/search?q=density%20fluctuations" title=" density fluctuations"> density fluctuations</a>, <a href="https://publications.waset.org/abstracts/search?q=attenuation%20coefficient" title=" attenuation coefficient "> attenuation coefficient </a> </p> <a href="https://publications.waset.org/abstracts/4810/the-contribution-of-density-fluctuations-in-ultrasound-scattering-in-cancellous-bone" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/4810.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">326</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8158</span> Distributed Acoustic Sensing Signal Model under Static Fiber Conditions</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=G.%20Punithavathy">G. Punithavathy</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The research proposes a statistical model for the distributed acoustic sensor interrogation units that broadcast a laser pulse into the fiber optics, where interactions within the fiber determine the localized acoustic energy that causes light reflections known as backscatter. The backscattered signal's amplitude and phase can be calculated using explicit equations. The created model makes amplitude signal spectrum and autocorrelation predictions that are confirmed by experimental findings. Phase signal characteristics that are useful for researching optical time domain reflectometry (OTDR) system sensing applications are provided and examined, showing good agreement with the experiment. The experiment was successfully done with the use of Python coding. In this research, we can analyze the entire distributed acoustic sensing (DAS) component parts separately. This model assumes that the fiber is in a static condition, meaning that there is no external force or vibration applied to the cable, that means no external acoustic disturbances present. The backscattered signal consists of a random noise component, which is caused by the intrinsic imperfections of the fiber, and a coherent component, which is due to the laser pulse interacting with the fiber. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=distributed%20acoustic%20sensing" title="distributed acoustic sensing">distributed acoustic sensing</a>, <a href="https://publications.waset.org/abstracts/search?q=optical%20fiber%20devices" title=" optical fiber devices"> optical fiber devices</a>, <a href="https://publications.waset.org/abstracts/search?q=optical%20time%20domain%20reflectometry" title=" optical time domain reflectometry"> optical time domain reflectometry</a>, <a href="https://publications.waset.org/abstracts/search?q=Rayleigh%20scattering" title=" Rayleigh scattering"> Rayleigh scattering</a> </p> <a href="https://publications.waset.org/abstracts/170787/distributed-acoustic-sensing-signal-model-under-static-fiber-conditions" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/170787.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">70</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8157</span> Numerical Calculation and Analysis of Fine Echo Characteristics of Underwater Hemispherical Cylindrical Shell</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Hongjian%20Jia">Hongjian Jia</a> </p> <p class="card-text"><strong>Abstract:</strong></p> A finite-length cylindrical shell with a spherical cap is a typical engineering approximation model of actual underwater targets. The research on the omni-directional acoustic scattering characteristics of this target model can provide a favorable basis for the detection and identification of actual underwater targets. The elastic resonance characteristics of the target are the results of the comprehensive effect of the target length, shell-thickness ratio and materials. Under the conditions of different materials and geometric dimensions, the coincidence resonance characteristics of the target have obvious differences. Aiming at this problem, this paper obtains the omni-directional acoustic scattering field of the underwater hemispherical cylindrical shell by numerical calculation and studies the influence of target geometric parameters (length, shell-thickness ratio) and material parameters on the coincidence resonance characteristics of the target in turn. The study found that the formant interval is not a stable value and changes with the incident angle. Among them, the formant interval is less affected by the target length and shell-thickness ratio and is significantly affected by the material properties, which is an effective feature for classifying and identifying targets of different materials. The quadratic polynomial is utilized to fully fit the change relationship between the formant interval and the angle. The results show that the three fitting coefficients of the stainless steel and aluminum targets are significantly different, which can be used as an effective feature parameter to characterize the target materials. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=hemispherical%20cylindrical%20shell%3B" title="hemispherical cylindrical shell;">hemispherical cylindrical shell;</a>, <a href="https://publications.waset.org/abstracts/search?q=fine%20echo%20characteristics%3B" title=" fine echo characteristics;"> fine echo characteristics;</a>, <a href="https://publications.waset.org/abstracts/search?q=geometric%20and%20material%20parameters%3B" title=" geometric and material parameters;"> geometric and material parameters;</a>, <a href="https://publications.waset.org/abstracts/search?q=formant%20interval" title=" formant interval"> formant interval</a> </p> <a href="https://publications.waset.org/abstracts/169606/numerical-calculation-and-analysis-of-fine-echo-characteristics-of-underwater-hemispherical-cylindrical-shell" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/169606.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">109</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8156</span> Light-Scattering Characteristics of Ordered Arrays Nobel Metal Nanoparticles</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Yassine%20Ait-El-Aoud">Yassine Ait-El-Aoud</a>, <a href="https://publications.waset.org/abstracts/search?q=Michael%20Okomoto"> Michael Okomoto</a>, <a href="https://publications.waset.org/abstracts/search?q=Andrew%20M.%20Luce"> Andrew M. Luce</a>, <a href="https://publications.waset.org/abstracts/search?q=Alkim%20Akyurtlu"> Alkim Akyurtlu</a>, <a href="https://publications.waset.org/abstracts/search?q=Richard%20M.%20Osgood%20III"> Richard M. Osgood III</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Light scattering of metal nanoparticles (NPs) has a unique, and technologically important effect on enhancing light absorption in substrates because most of the light scatters into the substrate near the localized plasmon resonance of the NPs. The optical response, such as the resonant frequency and forward- and backward-scattering, can be tuned to trap light over a certain spectral region by adjusting the nanoparticle material size, shape, aggregation state, Metallic vs. insulating state, as well as local environmental conditions. In this work, we examined the light scattering characteristics of ordered arrays of metal nanoparticles and the light trapping, in order to enhance absorption, by measuring the forward- and backward-scattering using a UV/VIS/NIR spectrophotometer. Samples were fabricated using the popular self-assembly process method: dip coating, combined with nanosphere lithography. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=dip%20coating" title="dip coating">dip coating</a>, <a href="https://publications.waset.org/abstracts/search?q=light-scattering" title=" light-scattering"> light-scattering</a>, <a href="https://publications.waset.org/abstracts/search?q=metal%20nanoparticles" title=" metal nanoparticles"> metal nanoparticles</a>, <a href="https://publications.waset.org/abstracts/search?q=nanosphere%20lithography" title=" nanosphere lithography"> nanosphere lithography</a> </p> <a href="https://publications.waset.org/abstracts/58313/light-scattering-characteristics-of-ordered-arrays-nobel-metal-nanoparticles" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/58313.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">328</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8155</span> The Scattering in Flexible Reactive Silencer Containing Rigid Partitioning</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Muhammad%20Afzal">Muhammad Afzal</a>, <a href="https://publications.waset.org/abstracts/search?q=Junaid%20Uzair%20Satti"> Junaid Uzair Satti</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The noise emanating from the ducting of heating, ventilation, and air-conditioning (HVAC) system is often attenuated by using the dissipative silencers. Such devices work well for the high-frequency noise but are less operative in the low-frequency noise range. The present study analyzes a reactive silencer comprising expansion chamber of the elastic membranes partitioned symmetrically by a rigid plate. The Mode-Matching scheme has been developed to solve the governing boundary value problem. The orthogonal and non-orthogonal duct modes of acoustic pressures and normal velocities are matched at interfaces. It enables to recast the differential system into the infinite system of linear algebraic of equations, which is, then truncated and inverted for the solution. The truncated solution is validated through the conservation of energy and reconstruction of matching conditions. The results for scattering energy flux and transmission loss are shown against frequency and the dimensions of the chamber. It is seen that the stop-band of the silencer can be shifted to the broadband by changing the dimensions of the chamber and the properties of the elastic membranes. The modeled reactive silencer is more efficient in low frequency regime where the passive devices are least effective. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=acoustic%20scattering" title="acoustic scattering">acoustic scattering</a>, <a href="https://publications.waset.org/abstracts/search?q=elastic%20membranes%20mode-matching" title=" elastic membranes mode-matching"> elastic membranes mode-matching</a>, <a href="https://publications.waset.org/abstracts/search?q=reactive%20silencer" title=" reactive silencer"> reactive silencer</a> </p> <a href="https://publications.waset.org/abstracts/93009/the-scattering-in-flexible-reactive-silencer-containing-rigid-partitioning" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/93009.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">146</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8154</span> Interpretation of Ultrasonic Backscatter of Linear FM Chirp Pulses from Targets Having Frequency-Dependent Scattering</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Stuart%20Bradley">Stuart Bradley</a>, <a href="https://publications.waset.org/abstracts/search?q=Mathew%20Legg"> Mathew Legg</a>, <a href="https://publications.waset.org/abstracts/search?q=Lilyan%20Panton"> Lilyan Panton</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Ultrasonic remote sensing is a useful tool for assessing the interior structure of complex targets. For these methods, significantly enhanced spatial resolution is obtained if the pulse is coded, for example using a linearly changing frequency during the pulse duration. Such pulses have a time-dependent spectral structure. Interpretation of the backscatter from targets is, therefore, complicated if the scattering is frequency-dependent. While analytic models are well established for steady sinusoidal excitations applied to simple shapes such as spheres, such models do not generally exist for temporally evolving excitations. Therefore, models are developed in the current paper for handling such signals so that the properties of the targets can be quantitatively evaluated while maintaining very high spatial resolution. Laboratory measurements on simple shapes are used to confirm the validity of the models. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=linear%20FM%20chirp" title="linear FM chirp">linear FM chirp</a>, <a href="https://publications.waset.org/abstracts/search?q=time-dependent%20acoustic%20scattering" title=" time-dependent acoustic scattering"> time-dependent acoustic scattering</a>, <a href="https://publications.waset.org/abstracts/search?q=ultrasonic%20remote%20sensing" title=" ultrasonic remote sensing"> ultrasonic remote sensing</a>, <a href="https://publications.waset.org/abstracts/search?q=ultrasonic%20scattering" title=" ultrasonic scattering"> ultrasonic scattering</a> </p> <a href="https://publications.waset.org/abstracts/62723/interpretation-of-ultrasonic-backscatter-of-linear-fm-chirp-pulses-from-targets-having-frequency-dependent-scattering" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/62723.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">316</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8153</span> 3D Numerical Studies on Jets Acoustic Characteristics of Chevron Nozzles for Aerospace Applications</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=R.%20Kanmaniraja">R. Kanmaniraja</a>, <a href="https://publications.waset.org/abstracts/search?q=R.%20Freshipali"> R. Freshipali</a>, <a href="https://publications.waset.org/abstracts/search?q=J.%20Abdullah"> J. Abdullah</a>, <a href="https://publications.waset.org/abstracts/search?q=K.%20Niranjan"> K. Niranjan</a>, <a href="https://publications.waset.org/abstracts/search?q=K.%20Balasubramani"> K. Balasubramani</a>, <a href="https://publications.waset.org/abstracts/search?q=V.%20R.%20Sanal%20Kumar"> V. R. Sanal Kumar</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The present environmental issues have made aircraft jet noise reduction a crucial problem in aero-acoustics research. Acoustic studies reveal that addition of chevrons to the nozzle reduces the sound pressure level reasonably with acceptable reduction in performance. In this paper comprehensive numerical studies on acoustic characteristics of different types of chevron nozzles have been carried out with non-reacting flows for the shape optimization of chevrons in supersonic nozzles for aerospace applications. The numerical studies have been carried out using a validated steady 3D density based, k-ε turbulence model. In this paper chevron with sharp edge, flat edge, round edge and U-type edge are selected for the jet acoustic characterization of supersonic nozzles. We observed that compared to the base model a case with round-shaped chevron nozzle could reduce 4.13% acoustic level with 0.6% thrust loss. We concluded that the prudent selection of the chevron shape will enable an appreciable reduction of the aircraft jet noise without compromising its overall performance. It is evident from the present numerical simulations that k-ε model can predict reasonably well the acoustic level of chevron supersonic nozzles for its shape optimization. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=supersonic%20nozzle" title="supersonic nozzle">supersonic nozzle</a>, <a href="https://publications.waset.org/abstracts/search?q=Chevron" title=" Chevron"> Chevron</a>, <a href="https://publications.waset.org/abstracts/search?q=acoustic%20level" title=" acoustic level"> acoustic level</a>, <a href="https://publications.waset.org/abstracts/search?q=shape%20optimization%20of%20Chevron%20nozzles" title=" shape optimization of Chevron nozzles"> shape optimization of Chevron nozzles</a>, <a href="https://publications.waset.org/abstracts/search?q=jet%20noise%20suppression" title=" jet noise suppression"> jet noise suppression</a> </p> <a href="https://publications.waset.org/abstracts/15252/3d-numerical-studies-on-jets-acoustic-characteristics-of-chevron-nozzles-for-aerospace-applications" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/15252.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">516</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8152</span> Influence of Bragg Reflectors Pairs on Resonance Characteristics of Solidly Mounted Resonators</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Vinita%20Choudhary">Vinita Choudhary</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The solidly mounted resonator (SMR) is a bulk acoustic wave-based device consisting of a piezoelectric layer sandwiched between two electrodes upon Bragg reflectors, which then are attached to a substrate. To transform the effective acoustic impedance of the substrate to a near zero value, the Bragg reflectors are composed of alternating high and low acoustic impedance layers of quarter-wavelength thickness. In this work presents the design and investigation of acoustic Bragg reflectors (ABRs) for solidly mounted bulk acoustic wave resonators through analysis and simulation. This performance of the resonator is analyzed using 1D Mason modeling. The performance parameters are the effect of Bragg pairs number on transmissivity, reflectivity, insertion loss, the electromechanical and quality factor of the 5GHz operating resonator. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=bragg%20reflectors" title="bragg reflectors">bragg reflectors</a>, <a href="https://publications.waset.org/abstracts/search?q=SMR" title=" SMR"> SMR</a>, <a href="https://publications.waset.org/abstracts/search?q=insertion%20loss" title=" insertion loss"> insertion loss</a>, <a href="https://publications.waset.org/abstracts/search?q=quality%20factor" title=" quality factor"> quality factor</a> </p> <a href="https://publications.waset.org/abstracts/164288/influence-of-bragg-reflectors-pairs-on-resonance-characteristics-of-solidly-mounted-resonators" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/164288.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">98</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8151</span> Assessment of the Occupancy’s Effect on Speech Intelligibility in Al-Madinah Holy Mosque</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Wasim%20Orfali">Wasim Orfali</a>, <a href="https://publications.waset.org/abstracts/search?q=Hesham%20Tolba"> Hesham Tolba</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This research investigates the acoustical characteristics of Al-Madinah Holy Mosque. Extensive field measurements were conducted in different locations of Al-Madinah Holy Mosque to characterize its acoustic characteristics. The acoustical characteristics are usually evaluated by the use of objective parameters in unoccupied rooms due to practical considerations. However, under normal conditions, the room occupancy can vary such characteristics due to the effect of the additional sound absorption present in the room or by the change in signal-to-noise ratio. Based on the acoustic measurements carried out in Al-Madinah Holy Mosque with and without occupancy, and the analysis of such measurements, the existence of acoustical deficiencies has been confirmed. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Al-Madinah%20Holy%20Mosque" title="Al-Madinah Holy Mosque">Al-Madinah Holy Mosque</a>, <a href="https://publications.waset.org/abstracts/search?q=mosque%20acoustics" title=" mosque acoustics"> mosque acoustics</a>, <a href="https://publications.waset.org/abstracts/search?q=speech%20intelligibility" title=" speech intelligibility"> speech intelligibility</a>, <a href="https://publications.waset.org/abstracts/search?q=worship%20sound" title=" worship sound"> worship sound</a> </p> <a href="https://publications.waset.org/abstracts/97808/assessment-of-the-occupancys-effect-on-speech-intelligibility-in-al-madinah-holy-mosque" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/97808.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">177</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8150</span> Using Probabilistic Neural Network (PNN) for Extracting Acoustic Microwaves (Bulk Acoustic Waves) in Piezoelectric Material</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Hafdaoui%20Hichem">Hafdaoui Hichem</a>, <a href="https://publications.waset.org/abstracts/search?q=Mehadjebia%20Cherifa"> Mehadjebia Cherifa</a>, <a href="https://publications.waset.org/abstracts/search?q=Benatia%20Djamel"> Benatia Djamel</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this paper, we propose a new method for Bulk detection of an acoustic microwave signal during the propagation of acoustic microwaves in a piezoelectric substrate (Lithium Niobate LiNbO3). We have used the classification by probabilistic neural network (PNN) as a means of numerical analysis in which we classify all the values of the real part and the imaginary part of the coefficient attenuation with the acoustic velocity in order to build a model from which we note the Bulk waves easily. These singularities inform us of presence of Bulk waves in piezoelectric materials. By which we obtain accurate values for each of the coefficient attenuation and acoustic velocity for Bulk waves. This study will be very interesting in modeling and realization of acoustic microwaves devices (ultrasound) based on the propagation of acoustic microwaves. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=piezoelectric%20material" title="piezoelectric material">piezoelectric material</a>, <a href="https://publications.waset.org/abstracts/search?q=probabilistic%20neural%20network%20%28PNN%29" title=" probabilistic neural network (PNN)"> probabilistic neural network (PNN)</a>, <a href="https://publications.waset.org/abstracts/search?q=classification" title=" classification"> classification</a>, <a href="https://publications.waset.org/abstracts/search?q=acoustic%20microwaves" title=" acoustic microwaves"> acoustic microwaves</a>, <a href="https://publications.waset.org/abstracts/search?q=bulk%20waves" title=" bulk waves"> bulk waves</a>, <a href="https://publications.waset.org/abstracts/search?q=the%20attenuation%20coefficient" title=" the attenuation coefficient"> the attenuation coefficient</a> </p> <a href="https://publications.waset.org/abstracts/43264/using-probabilistic-neural-network-pnn-for-extracting-acoustic-microwaves-bulk-acoustic-waves-in-piezoelectric-material" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/43264.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">432</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8149</span> Interaction of Low-Energy Positrons with Mg Atoms: Elastic Scattering, Bound States, and Annihilation</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Mahasen%20M.%20Abdel%20Mageed">Mahasen M. Abdel Mageed</a>, <a href="https://publications.waset.org/abstracts/search?q=H.%20S.%20Zaghloul"> H. S. Zaghloul</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Annihilations, phase shifts, scattering lengths, and elastic cross sections of low energy positrons scattering from magnesium atoms were studied using the least-squares variational method (LSVM). The possibility of positron binding to the magnesium atoms is investigated. A trial wavefunction is suggested to represent e+-Mg elastic scattering and scattering parameters were derived to estimate the binding energy and annihilation rates. The trial function is taken to depend on several adjustable parameters and is improved iteratively by increasing the number of terms. The present results have the same behavior as reported semi-empirical, theoretical, and experimental results. Especially, the estimated positive scattering length supports the possibility of positron-magnesium bound state system that was confirmed in previous experimental and theoretical work. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=bound%20wavefunction" title="bound wavefunction">bound wavefunction</a>, <a href="https://publications.waset.org/abstracts/search?q=positron%20annihilation" title=" positron annihilation"> positron annihilation</a>, <a href="https://publications.waset.org/abstracts/search?q=scattering%20phase%20shift" title=" scattering phase shift"> scattering phase shift</a>, <a href="https://publications.waset.org/abstracts/search?q=scattering%20length" title=" scattering length"> scattering length</a> </p> <a href="https://publications.waset.org/abstracts/20154/interaction-of-low-energy-positrons-with-mg-atoms-elastic-scattering-bound-states-and-annihilation" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/20154.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">555</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8148</span> Embedded System of Signal Processing on FPGA: Underwater Application Architecture</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Abdelkader%20Elhanaoui">Abdelkader Elhanaoui</a>, <a href="https://publications.waset.org/abstracts/search?q=Mhamed%20Hadji"> Mhamed Hadji</a>, <a href="https://publications.waset.org/abstracts/search?q=Rachid%20Skouri"> Rachid Skouri</a>, <a href="https://publications.waset.org/abstracts/search?q=Said%20Agounad"> Said Agounad</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The purpose of this paper is to study the phenomenon of acoustic scattering by using a new method. The signal processing (Fast Fourier Transform FFT Inverse Fast Fourier Transform iFFT and BESSEL functions) is widely applied to obtain information with high precision accuracy. Signal processing has a wider implementation in general-purpose pro-cessors. Our interest was focused on the use of FPGAs (Field-Programmable Gate Ar-rays) in order to minimize the computational complexity in single processor architecture, then be accelerated on FPGA and meet real-time and energy efficiency requirements. Gen-eral-purpose processors are not efficient for signal processing. We implemented the acous-tic backscattered signal processing model on the Altera DE-SOC board and compared it to Odroid xu4. By comparison, the computing latency of Odroid xu4 and FPGA is 60 sec-onds and 3 seconds, respectively. The detailed SoC FPGA-based system has shown that acoustic spectra are performed up to 20 times faster than the Odroid xu4 implementation. FPGA-based system of processing algorithms is realized with an absolute error of about 10⁻³. This study underlines the increasing importance of embedded systems in underwater acoustics, especially in non-destructive testing. It is possible to obtain information related to the detection and characterization of submerged cells. So we have achieved good exper-imental results in real-time and energy efficiency. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=DE1%20FPGA" title="DE1 FPGA">DE1 FPGA</a>, <a href="https://publications.waset.org/abstracts/search?q=acoustic%20scattering" title=" acoustic scattering"> acoustic scattering</a>, <a href="https://publications.waset.org/abstracts/search?q=form%20function" title=" form function"> form function</a>, <a href="https://publications.waset.org/abstracts/search?q=signal%20processing" title=" signal processing"> signal processing</a>, <a href="https://publications.waset.org/abstracts/search?q=non-destructive%20testing" title=" non-destructive testing"> non-destructive testing</a> </p> <a href="https://publications.waset.org/abstracts/162313/embedded-system-of-signal-processing-on-fpga-underwater-application-architecture" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/162313.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">79</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8147</span> Analysis of Combined Heat Transfer through the Core Materials of VIPs with Various Scattering Properties</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Jaehyug%20Lee">Jaehyug Lee</a>, <a href="https://publications.waset.org/abstracts/search?q=Tae-Ho%20Song"> Tae-Ho Song</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Vacuum insulation panel (VIP) can achieve very low thermal conductivity by evacuating its inner space. Heat transfer in the core materials of highly-evacuated VIP occurs by conduction through the solid structure and radiation through the pore. The effect of various scattering modes in combined conduction-radiation in VIP is investigated through numerical analysis. The discrete ordinates interpolation method (DOIM) incorporated with the commercial code FLUENT® is employed. It is found that backward scattering is more effective in reducing the total heat transfer while isotropic scattering is almost identical with pure absorbing/emitting case of the same optical thickness. For a purely scattering medium, the results agree well with additive solution with diffusion approximation, while a modified term is added in the effect of optical thickness to backward scattering is employed. For other scattering phase functions, it is also confirmed that backwardly scattering phase function gives a lower effective thermal conductivity. Thus, the materials with backward scattering properties, with radiation shields are desirable to lower the thermal conductivity of VIPs. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=combined%20conduction%20and%20radiation" title="combined conduction and radiation">combined conduction and radiation</a>, <a href="https://publications.waset.org/abstracts/search?q=discrete%20ordinates%20interpolation%20method" title=" discrete ordinates interpolation method"> discrete ordinates interpolation method</a>, <a href="https://publications.waset.org/abstracts/search?q=scattering%20phase%20function" title=" scattering phase function"> scattering phase function</a>, <a href="https://publications.waset.org/abstracts/search?q=vacuum%20insulation%20panel" title=" vacuum insulation panel"> vacuum insulation panel</a> </p> <a href="https://publications.waset.org/abstracts/19426/analysis-of-combined-heat-transfer-through-the-core-materials-of-vips-with-various-scattering-properties" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/19426.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">366</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8146</span> Regularities of Changes in the Fractal Dimension of Acoustic Emission Signals in the Stages Close to the Destruction of Structural Materials When Exposed to Low-Cycle Loaded</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Phyo%20Wai%20Aung">Phyo Wai Aung</a>, <a href="https://publications.waset.org/abstracts/search?q=Sysoev%20Oleg%20Evgenevich"> Sysoev Oleg Evgenevich</a>, <a href="https://publications.waset.org/abstracts/search?q=Boris%20Necolavet%20Maryin"> Boris Necolavet Maryin</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The article deals with theoretical problems of correlation of processes of microstructure changes of structural materials under cyclic loading and acoustic emission. The ways of the evolution of a microstructure under the influence of cyclic loading are shown depending on the structure of the initial crystal structure of the material. The spectra of the frequency characteristics of acoustic emission signals are experimentally obtained when testing titanium samples for cyclic loads. Changes in the fractal dimension of the acoustic emission signals in the selected frequency bands during the evolution of the microstructure of structural materials from the action of cyclic loads, as well as in the destruction of samples, are studied. The experimental samples were made of VT-20 structural material widely used in aircraft and rocket engineering. The article shows the striving of structural materials for synergistic stability and reduction of the fractal dimension of acoustic emission signals, in accordance with the degradation of the microstructure, which occurs as a result of fatigue processes from the action of low cycle loads. As a result of the research, the frequency range of acoustic emission signals of 100-270 kHz is determined, in which the fractal dimension of the signals, it is possible to most reliably predict the durability of structural materials. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=cyclic%20loadings" title="cyclic loadings">cyclic loadings</a>, <a href="https://publications.waset.org/abstracts/search?q=material%20structure%20changing" title=" material structure changing"> material structure changing</a>, <a href="https://publications.waset.org/abstracts/search?q=acoustic%20emission" title=" acoustic emission"> acoustic emission</a>, <a href="https://publications.waset.org/abstracts/search?q=fractal%20dimension" title=" fractal dimension"> fractal dimension</a> </p> <a href="https://publications.waset.org/abstracts/90632/regularities-of-changes-in-the-fractal-dimension-of-acoustic-emission-signals-in-the-stages-close-to-the-destruction-of-structural-materials-when-exposed-to-low-cycle-loaded" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/90632.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">262</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8145</span> Stimulated Raman Scattering of Ultra Intense Hollow Gaussian Beam</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Prerana%20Sharma">Prerana Sharma</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Effect of relativistic nonlinearity on stimulated Raman scattering of the propagating laser beam carrying null intensity in center (hollow Gaussian beam) by excited plasma wave are studied in a collisionless plasma. The construction of the equations is done employing the fluid theory which is developed with partial differential equation and Maxwell’s equations. The analysis is done using eikonal method. The phenonmenon of Stimulated Raman scattering is shown along with the excitation of seed plasma wave. The power of plasma wave and back reflectivity is observed for higher order of hollow Gaussian beam. Back reflectivity is studied numerically for various orders of HGLB with different value of plasma density, laser power and beam radius. Numerical analysis shows that these parameters play vital role on reflectivity characteristics. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Hollow%20Gaussian%20beam" title="Hollow Gaussian beam">Hollow Gaussian beam</a>, <a href="https://publications.waset.org/abstracts/search?q=relativistic%20nonlinearity" title=" relativistic nonlinearity"> relativistic nonlinearity</a>, <a href="https://publications.waset.org/abstracts/search?q=plasma%20physics" title=" plasma physics"> plasma physics</a>, <a href="https://publications.waset.org/abstracts/search?q=Raman%20scattering" title=" Raman scattering"> Raman scattering</a> </p> <a href="https://publications.waset.org/abstracts/15768/stimulated-raman-scattering-of-ultra-intense-hollow-gaussian-beam" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/15768.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">638</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8144</span> Effects of Charge Fluctuating Positive Dust on Linear Dust-Acoustic Waves </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Sanjit%20Kumar%20Paul">Sanjit Kumar Paul</a>, <a href="https://publications.waset.org/abstracts/search?q=A.%20A.%20Mamun"> A. A. Mamun</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20R.%20Amin"> M. R. Amin</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The Linear propagation of the dust-acoustic wave in a dusty plasma consisting of Boltzmann distributed electrons and ions and mobile charge fluctuating positive dust grains has been investigated by employing the reductive perturbation method. It has been shown that the dust charge fluctuation is a source of dissipation and its responsible for the formation of the dust-acoustic waves in such a dusty plasma. The basic features of such dust-acoustic waves have been identified. It has been proposed to design a new laboratory experiment which will be able to identify the basic features of the dust-acoustic waves predicted in this theoretical investigation. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=dust%20acoustic%20waves" title="dust acoustic waves">dust acoustic waves</a>, <a href="https://publications.waset.org/abstracts/search?q=dusty%20plasma" title=" dusty plasma"> dusty plasma</a>, <a href="https://publications.waset.org/abstracts/search?q=Boltzmann%20distributed%20electrons" title=" Boltzmann distributed electrons"> Boltzmann distributed electrons</a>, <a href="https://publications.waset.org/abstracts/search?q=charge%20fluctuation" title=" charge fluctuation"> charge fluctuation</a> </p> <a href="https://publications.waset.org/abstracts/8380/effects-of-charge-fluctuating-positive-dust-on-linear-dust-acoustic-waves" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/8380.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">637</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8143</span> Thermodynamic Trends in Co-Based Alloys via Inelastic Neutron Scattering</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Paul%20Stonaha">Paul Stonaha</a>, <a href="https://publications.waset.org/abstracts/search?q=Mariia%20Romashchenko"> Mariia Romashchenko</a>, <a href="https://publications.waset.org/abstracts/search?q=Xaio%20Xu"> Xaio Xu</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Magnetic shape memory alloys (MSMAs) are promising technological materials for a range of fields, from biomaterials to energy harvesting. We have performed inelastic neutron scattering on two powder samples of cobalt-based high-entropy MSMAs across a range of temperatures in an effort to compare calculations of thermodynamic properties (entropy, specific heat, etc.) to the measured ones. The measurements were correct for multiphonon scattering and multiple scattering contributions. We present herein the neutron-weighted vibrational density of states. Future work will utilize DFT calculations of the disordered lattice to correct for the neutron weighting and retrieve the true thermodynamical properties. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=neutron%20scattering" title="neutron scattering">neutron scattering</a>, <a href="https://publications.waset.org/abstracts/search?q=vibrational%20dynamics" title=" vibrational dynamics"> vibrational dynamics</a>, <a href="https://publications.waset.org/abstracts/search?q=computational%20physics" title=" computational physics"> computational physics</a>, <a href="https://publications.waset.org/abstracts/search?q=material%20science" title=" material science"> material science</a> </p> <a href="https://publications.waset.org/abstracts/189169/thermodynamic-trends-in-co-based-alloys-via-inelastic-neutron-scattering" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/189169.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">32</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8142</span> Dipole and Quadrupole Scattering of Ultra Short Pulses on Metal Nanospheres</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Sergey%20Svita">Sergey Svita</a>, <a href="https://publications.waset.org/abstracts/search?q=Valeriy%20Astapenko"> Valeriy Astapenko</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The presentation is devoted to the theoretical analysis of ultrashort electromagnetic pulses (USP) scattering on metallic nanospheres in a dielectric medium in the vicinity of surface plasmon resonance due to excitation of dipole and quadrupole surface plasmons. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=surface%20plasmon" title="surface plasmon">surface plasmon</a>, <a href="https://publications.waset.org/abstracts/search?q=scattering" title=" scattering"> scattering</a>, <a href="https://publications.waset.org/abstracts/search?q=metallic%20%20nanosphere" title=" metallic nanosphere"> metallic nanosphere</a> </p> <a href="https://publications.waset.org/abstracts/27368/dipole-and-quadrupole-scattering-of-ultra-short-pulses-on-metal-nanospheres" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/27368.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">379</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8141</span> Acoustic Characteristics of Ḫijaiyaḫ Letters Pronunciation by Indonesian Native Speaker</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Romi%20Hardiyansyah">Romi Hardiyansyah</a>, <a href="https://publications.waset.org/abstracts/search?q=Raden%20Sugeng%20Joko%20Sarwono"> Raden Sugeng Joko Sarwono</a>, <a href="https://publications.waset.org/abstracts/search?q=Agus%20Samsi"> Agus Samsi</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Indonesian people have a mother language but not Arabic. Meanwhile, they must be able to pronounce the Arabic because Islam is the biggest religion in Indonesia. Arabic is composed by ḫijaiyaḫ letters which has its own pronunciation. Sound production process in humans can be divided into three physiological processes, namely: the formation of airflow from the lungs, the change in airflow from the lungs into the sound, and articulation (the modulation/sound setting into a specific sound). Ḫijaiyaḫ letters has its own articulation, some of which seem strange for most people in Indonesia. Those letters come out from the middle and upper throat so that the letters has its own acoustic characteristics. Acoustic characteristics of voice can be observed by source-filter approach that has parameters: pitch, formant, and formant bandwidth. Pitch is the basic tone in every human being. Formant is the resonance frequency of the human voice. Formant bandwidth is the time-width of a formant. After recording the sound from 21 subjects, data is processed by software Praat version 5.3.39. The analysis showed that each pronunciation, syakal (vowel changer), and the place of discharge letters has the same timbre which are determined by third and fourth formant. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=%E1%B8%ABijaiya%E1%B8%AB" title="ḫijaiyaḫ">ḫijaiyaḫ</a>, <a href="https://publications.waset.org/abstracts/search?q=articulation" title=" articulation"> articulation</a>, <a href="https://publications.waset.org/abstracts/search?q=pitch" title=" pitch"> pitch</a>, <a href="https://publications.waset.org/abstracts/search?q=formant" title=" formant"> formant</a>, <a href="https://publications.waset.org/abstracts/search?q=formant%20bandwidth" title=" formant bandwidth"> formant bandwidth</a>, <a href="https://publications.waset.org/abstracts/search?q=timbre" title=" timbre"> timbre</a> </p> <a href="https://publications.waset.org/abstracts/36324/acoustic-characteristics-of-ijaiya-letters-pronunciation-by-indonesian-native-speaker" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/36324.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">396</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8140</span> On the Study of the Electromagnetic Scattering by Large Obstacle Based on the Method of Auxiliary Sources</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Hidouri%20Sami">Hidouri Sami</a>, <a href="https://publications.waset.org/abstracts/search?q=Aguili%20Taoufik"> Aguili Taoufik</a> </p> <p class="card-text"><strong>Abstract:</strong></p> We consider fast and accurate solutions of scattering problems by large perfectly conducting objects (PEC) formulated by an optimization of the Method of Auxiliary Sources (MAS). We present various techniques used to reduce the total computational cost of the scattering problem. The first technique is based on replacing the object by an array of finite number of small (PEC) object with the same shape. The second solution reduces the problem on considering only the half of the object.These two solutions are compared to results from the reference bibliography. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=method%20of%20auxiliary%20sources" title="method of auxiliary sources">method of auxiliary sources</a>, <a href="https://publications.waset.org/abstracts/search?q=scattering" title=" scattering"> scattering</a>, <a href="https://publications.waset.org/abstracts/search?q=large%20object" title=" large object"> large object</a>, <a href="https://publications.waset.org/abstracts/search?q=RCS" title=" RCS"> RCS</a>, <a href="https://publications.waset.org/abstracts/search?q=computational%20resources" title=" computational resources"> computational resources</a> </p> <a href="https://publications.waset.org/abstracts/38516/on-the-study-of-the-electromagnetic-scattering-by-large-obstacle-based-on-the-method-of-auxiliary-sources" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/38516.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">241</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8139</span> ReS, Resonant String Shell: Development of an Acoustic Shell for Outdoor Chamber Music Concerts</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Serafino%20Di%20Rosario">Serafino Di Rosario</a> </p> <p class="card-text"><strong>Abstract:</strong></p> ReS is a sustainable hand-built temporary acoustic shell, developed since 2011 and built during the architectural workshop at Villa Pennisi in Musica in Acireale, Sicily, each year since 2012. The design concept aims to provide a portable structure by reducing the on-site construction problems and the skills required by the builders together with maximizing the acoustic performance for the audience and the musicians. The shell is built using only wood, recycled for the most part, and can be built and dismantled by non-specialized workers in just three days. This paper describes the research process, which spans over four years and presents the final results in form of acoustic simulations performed by acoustic modeling software and real world measurements. ReS is developed by the ReS team who has been presented with the Peter Lord Award in 2015 by the Institute of Acoustics in the UK. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=acoustic%20shell" title="acoustic shell">acoustic shell</a>, <a href="https://publications.waset.org/abstracts/search?q=outdoor%20natural%20amplification" title=" outdoor natural amplification"> outdoor natural amplification</a>, <a href="https://publications.waset.org/abstracts/search?q=computational%20design" title=" computational design"> computational design</a>, <a href="https://publications.waset.org/abstracts/search?q=room%20acoustics" title=" room acoustics"> room acoustics</a> </p> <a href="https://publications.waset.org/abstracts/67117/res-resonant-string-shell-development-of-an-acoustic-shell-for-outdoor-chamber-music-concerts" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/67117.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">228</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8138</span> Numerical Study on Vortex-Driven Pressure Oscillation and Roll Torque Characteristics in a SRM with Two Inhibitors</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ji-Seok%20Hong">Ji-Seok Hong</a>, <a href="https://publications.waset.org/abstracts/search?q=Hee-Jang%20Moon"> Hee-Jang Moon</a>, <a href="https://publications.waset.org/abstracts/search?q=Hong-Gye%20Sung"> Hong-Gye Sung</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The details of flow structures and the coupling mechanism between vortex shedding and acoustic excitation in a solid rocket motor with two inhibitors have been investigated using 3D Large Eddy Simulation (LES) and Proper Orthogonal Decomposition (POD) analysis. The oscillation frequencies and vortex shedding periods from two inhibitors compare reasonably well with the experimental data and numerical result. A total of four different locations of the rear inhibitor has been numerically tested to characterize the coupling relation of vortex shedding frequency and acoustic mode. The major source of triggering pressure oscillation in the combustor is the resonance with the acoustic longitudinal half mode. It was observed that the counter-rotating vortices in the nozzle flow produce roll torque. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=large%20eddy%20simulation" title="large eddy simulation">large eddy simulation</a>, <a href="https://publications.waset.org/abstracts/search?q=proper%20orthogonal%20decomposition" title=" proper orthogonal decomposition"> proper orthogonal decomposition</a>, <a href="https://publications.waset.org/abstracts/search?q=SRM%20instability" title=" SRM instability"> SRM instability</a>, <a href="https://publications.waset.org/abstracts/search?q=flow-acoustic%20coupling" title=" flow-acoustic coupling"> flow-acoustic coupling</a> </p> <a href="https://publications.waset.org/abstracts/1480/numerical-study-on-vortex-driven-pressure-oscillation-and-roll-torque-characteristics-in-a-srm-with-two-inhibitors" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/1480.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">565</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8137</span> Analytical Solutions for Geodesic Acoustic Eigenmodes in Tokamak Plasmas</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Victor%20I.%20Ilgisonis">Victor I. Ilgisonis</a>, <a href="https://publications.waset.org/abstracts/search?q=Ludmila%20V.%20Konovaltseva"> Ludmila V. Konovaltseva</a>, <a href="https://publications.waset.org/abstracts/search?q=Vladimir%20P.%20Lakhin"> Vladimir P. Lakhin</a>, <a href="https://publications.waset.org/abstracts/search?q=Ekaterina%20A.%20Sorokina"> Ekaterina A. Sorokina</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The analytical solutions for geodesic acoustic eigenmodes in tokamak plasmas with circular concentric magnetic surfaces are found. In the frame of ideal magnetohydrodynamics the dispersion relation taking into account the toroidal coupling between electrostatic perturbations and electromagnetic perturbations with poloidal mode number |m| = 2 is derived. In the absence of such a coupling the dispersion relation gives the standard continuous spectrum of geodesic acoustic modes. The analysis of the existence of global eigenmodes for plasma equilibria with both off-axis and on-axis maximum of the local geodesic acoustic frequency is performed. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=tokamak" title="tokamak">tokamak</a>, <a href="https://publications.waset.org/abstracts/search?q=MHD" title=" MHD"> MHD</a>, <a href="https://publications.waset.org/abstracts/search?q=geodesic%20acoustic%20mode" title=" geodesic acoustic mode"> geodesic acoustic mode</a>, <a href="https://publications.waset.org/abstracts/search?q=eigenmode" title=" eigenmode"> eigenmode</a> </p> <a href="https://publications.waset.org/abstracts/11335/analytical-solutions-for-geodesic-acoustic-eigenmodes-in-tokamak-plasmas" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/11335.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">734</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8136</span> Multi-Sender MAC Protocol Based on Temporal Reuse in Underwater Acoustic Networks</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Dongwon%20Lee">Dongwon Lee</a>, <a href="https://publications.waset.org/abstracts/search?q=Sunmyeng%20Kim"> Sunmyeng Kim</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Underwater acoustic networks (UANs) have become a very active research area in recent years. Compared with wireless networks, UANs are characterized by the limited bandwidth, long propagation delay and high channel dynamic in acoustic modems, which pose challenges to the design of medium access control (MAC) protocol. The characteristics severely affect network performance. In this paper, we study a MS-MAC (Multi-Sender MAC) protocol in order to improve network performance. The proposed protocol exploits temporal reuse by learning the propagation delays to neighboring nodes. A source node locally calculates the transmission schedules of its neighboring nodes and itself based on the propagation delays to avoid collisions. Performance evaluation is conducted using simulation, and confirms that the proposed protocol significantly outperforms the previous protocol in terms of throughput. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=acoustic%20channel" title="acoustic channel">acoustic channel</a>, <a href="https://publications.waset.org/abstracts/search?q=MAC" title=" MAC"> MAC</a>, <a href="https://publications.waset.org/abstracts/search?q=temporal%20reuse" title=" temporal reuse"> temporal reuse</a>, <a href="https://publications.waset.org/abstracts/search?q=UAN" title=" UAN"> UAN</a> </p> <a href="https://publications.waset.org/abstracts/43015/multi-sender-mac-protocol-based-on-temporal-reuse-in-underwater-acoustic-networks" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/43015.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">348</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8135</span> Test Research on Damage Initiation and Development of a Concrete Beam Using Acoustic Emission Technology</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Xiang%20Wang">Xiang Wang</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In order to validate the efficiency of recognizing the damage initiation and development of a concrete beam using acoustic emission technology, a concrete beam is built and tested in the laboratory. The acoustic emission signals are analyzed based on both parameter and wave information, which is also compared with the beam deflection measured by displacement sensors. The results indicate that using acoustic emission technology can detect damage initiation and development effectively, especially in the early stage of the damage development, which can not be detected by the common monitoring technology. Furthermore, the positioning of the damage based on the acoustic emission signals can be proved to be reasonable. This job can be an important attempt for the future long-time monitoring of the real concrete structure. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=acoustic%20emission%20technology" title="acoustic emission technology">acoustic emission technology</a>, <a href="https://publications.waset.org/abstracts/search?q=concrete%20beam" title=" concrete beam"> concrete beam</a>, <a href="https://publications.waset.org/abstracts/search?q=parameter%20analysis" title=" parameter analysis"> parameter analysis</a>, <a href="https://publications.waset.org/abstracts/search?q=wave%20analysis" title=" wave analysis"> wave analysis</a>, <a href="https://publications.waset.org/abstracts/search?q=positioning" title=" positioning"> positioning</a> </p> <a href="https://publications.waset.org/abstracts/108497/test-research-on-damage-initiation-and-development-of-a-concrete-beam-using-acoustic-emission-technology" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/108497.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">141</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8134</span> Experimental Approach for Determining Hemi-Anechoic Characteristics of Engineering Acoustical Test Chambers</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Santiago%20Montoya-Ospina">Santiago Montoya-Ospina</a>, <a href="https://publications.waset.org/abstracts/search?q=Ra%C3%BAl%20E.%20Jim%C3%A9nez-Mej%C3%ADa"> Raúl E. Jiménez-Mejía</a>, <a href="https://publications.waset.org/abstracts/search?q=Rosa%20Elvira%20Correa%20Guti%C3%A9rrez"> Rosa Elvira Correa Gutiérrez</a> </p> <p class="card-text"><strong>Abstract:</strong></p> An experimental methodology is proposed for determining hemi-anechoic characteristics of an engineering acoustic room built at the facilities of Universidad Nacional de Colombia to evaluate the free-field conditions inside the chamber. Experimental results were compared with theoretical ones in both, the source and the sound propagation inside the chamber. Acoustic source was modeled by using monopole radiation pattern from punctual sources and the image method was considered for dealing with the reflective plane of the room, that means, the floor without insulation. Finite-difference time-domain (FDTD) method was implemented to calculate the sound pressure value at every spatial point of the chamber. Comparison between theoretical and experimental data yields to minimum error, giving satisfactory results for the hemi-anechoic characterization of the chamber. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=acoustic%20impedance" title="acoustic impedance">acoustic impedance</a>, <a href="https://publications.waset.org/abstracts/search?q=finite-difference%20time-domain" title=" finite-difference time-domain"> finite-difference time-domain</a>, <a href="https://publications.waset.org/abstracts/search?q=hemi-anechoic%20characterization" title=" hemi-anechoic characterization"> hemi-anechoic characterization</a> </p> <a href="https://publications.waset.org/abstracts/86159/experimental-approach-for-determining-hemi-anechoic-characteristics-of-engineering-acoustical-test-chambers" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/86159.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">162</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8133</span> Mueller Matrix Polarimetry for Analysis Scattering Biological Fluid Media</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=S.%20Cherif">S. Cherif</a>, <a href="https://publications.waset.org/abstracts/search?q=A.%20Medjahed"> A. Medjahed</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20Bouafia"> M. Bouafia</a>, <a href="https://publications.waset.org/abstracts/search?q=A.%20Manallah"> A. Manallah</a> </p> <p class="card-text"><strong>Abstract:</strong></p> A light wave is characterized by 4 characteristics: its amplitude, its frequency, its phase and the direction of polarization of its luminous vector (the electric field). It is in this last characteristic that we will be interested. The polarization of the light was introduced in order to describe the vectorial behavior of the light; it describes the way in which the electric field evolves in a point of space. Our work consists in studying diffusing mediums. Different types of biological fluids were selected to study the evolution of each with increasing scattering power of the medium, and in the same time to make a comparison between them. When crossing these mediums, the light undergoes modifications and/or deterioration of its initial state of polarization. This phenomenon is related to the properties of the medium, the idea is to compare the characteristics of the entering and outgoing light from the studied medium by a white light. The advantage of this model is that it is experimentally accessible workable intensity measurements with CCD sensors and allows operation in 2D. The latter information is used to discriminate some physical properties of the studied areas. We chose four types of milk to study the evolution of each with increasing scattering power of the medium. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=light%20polarization" title="light polarization">light polarization</a>, <a href="https://publications.waset.org/abstracts/search?q=Mueller%20matrix" title=" Mueller matrix"> Mueller matrix</a>, <a href="https://publications.waset.org/abstracts/search?q=Mueller%20images" title=" Mueller images"> Mueller images</a>, <a href="https://publications.waset.org/abstracts/search?q=diffusing%20medium" title=" diffusing medium"> diffusing medium</a>, <a href="https://publications.waset.org/abstracts/search?q=milk" title=" milk "> milk </a> </p> <a href="https://publications.waset.org/abstracts/26216/mueller-matrix-polarimetry-for-analysis-scattering-biological-fluid-media" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/26216.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">330</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">8132</span> Effects of Positron Concentration and Temperature on Ion-Acoustic Solitons in Magnetized Electron-Positron-Ion Plasma</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=S.%20K.%20Jain">S. K. Jain</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20K.%20Mishra"> M. K. Mishra</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Oblique propagation of ion-acoustic solitons in magnetized electron-positron-ion (EPI) plasma with warm adiabatic ions and isothermal electrons has been studied. Korteweg-de Vries (KdV) equation using reductive perturbation method has been derived for the system, which admits an obliquely propagating soliton solution. It is found that for the selected set of parameter values, the system supports only compressive solitons. Investigations reveal that an increase in positron concentration diminishes the amplitude as well as the width of the soliton. It is also found that the temperature ratio of electron to positron (γ) affects the amplitude of the solitary wave. An external magnetic field do not affect the amplitude of ion-acoustic solitons, but obliqueness angle (θ), the angle between wave vector and magnetic field affects the amplitude. The amplitude of the ion-acoustic solitons increases with increase in angle of obliqueness. Magnetization and obliqueness drastically affect the width of the soliton. An increase in ionic temperature decreases the amplitude and width. For the fixed set of parameters, profiles have been drawn to study the combined effect with variation of two parameters on the characteristics of the ion-acoustic solitons (i.e., amplitude and width). The result may be applicable to plasma in the laboratory as well as in the magnetospheric region of the earth. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=ion-acoustic%20solitons" title="ion-acoustic solitons">ion-acoustic solitons</a>, <a href="https://publications.waset.org/abstracts/search?q=Korteweg-de%20Vries%20%28KdV%29%20equation" title=" Korteweg-de Vries (KdV) equation"> Korteweg-de Vries (KdV) equation</a>, <a href="https://publications.waset.org/abstracts/search?q=magnetized%20electron-positron-ion%20%28EPI%29%20plasma" title=" magnetized electron-positron-ion (EPI) plasma"> magnetized electron-positron-ion (EPI) plasma</a>, <a href="https://publications.waset.org/abstracts/search?q=reductive%20perturbation%20method" title=" reductive perturbation method"> reductive perturbation method</a> </p> <a href="https://publications.waset.org/abstracts/48847/effects-of-positron-concentration-and-temperature-on-ion-acoustic-solitons-in-magnetized-electron-positron-ion-plasma" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/48847.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">293</span> </span> </div> </div> <ul class="pagination"> <li class="page-item disabled"><span class="page-link">&lsaquo;</span></li> <li class="page-item active"><span class="page-link">1</span></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=acoustic%20scattering%20characteristics&page=2">2</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=acoustic%20scattering%20characteristics&page=3">3</a></li> <li class="page-item"><a class="page-link" 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