CINXE.COM

<!DOCTYPE html> <html lang="en" dir="ltr"> <head>  <script async src="https://www.googletagmanager.com/gtag/js?id=G-P63WKM1TM1"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); gtag('config', 'G-P63WKM1TM1'); </script>  <script type="text/javascript" > (function(m,e,t,r,i,k,a){m[i]=m[i]||function(){(m[i].a=m[i].a||[]).push(arguments)}; m[i].l=1*new Date(); for (var j = 0; j < document.scripts.length; j++) {if (document.scripts[j].src === r) { return; }} k=e.createElement(t),a=e.getElementsByTagName(t)[0],k.async=1,k.src=r,a.parentNode.insertBefore(k,a)}) (window, document, "script", "https://mc.yandex.ru/metrika/tag.js", "ym"); ym(55165297, "init", { clickmap:false, trackLinks:true, accurateTrackBounce:true, webvisor:false }); </script> <noscript><div><img src="https://mc.yandex.ru/watch/55165297" style="position:absolute; left:-9999px;" alt="" /></div></noscript>    <title>Search results for: laser doppler velocimeter</title> <meta name="description" content="Search results for: laser doppler velocimeter"> <meta name="keywords" content="laser doppler velocimeter"> <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 Excellence" /> </a> <button class="d-block d-lg-none navbar-toggler ml-auto" type="button" data-toggle="collapse" data-target="#navbarMenu" aria-controls="navbarMenu" aria-expanded="false" aria-label="Toggle navigation"> <span class="navbar-toggler-icon"></span> </button> <div class="w-100"> <div class="d-none d-lg-flex flex-row-reverse"> <form method="get" action="https://waset.org/search" class="form-inline my-2 my-lg-0"> <input class="form-control mr-sm-2" type="search" placeholder="Search Conferences" value="laser doppler velocimeter" name="q" aria-label="Search"> <button class="btn btn-light my-2 my-sm-0" type="submit"><i class="fas fa-search"></i></button> </form> </div> <div class="collapse navbar-collapse mt-1" id="navbarMenu"> <ul class="navbar-nav ml-auto align-items-center" id="mainNavMenu"> <li class="nav-item"> <a class="nav-link" href="https://waset.org/conferences" title="Conferences in 2024/2025/2026">Conferences</a> </li> <li class="nav-item"> <a class="nav-link" href="https://waset.org/disciplines" title="Disciplines">Disciplines</a> </li> <li class="nav-item"> <a class="nav-link" href="https://waset.org/committees" rel="nofollow">Committees</a> </li> <li class="nav-item dropdown"> <a class="nav-link dropdown-toggle" href="#" id="navbarDropdownPublications" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> Publications </a> <div class="dropdown-menu" aria-labelledby="navbarDropdownPublications"> <a class="dropdown-item" href="https://publications.waset.org/abstracts">Abstracts</a> <a class="dropdown-item" href="https://publications.waset.org">Periodicals</a> <a class="dropdown-item" href="https://publications.waset.org/archive">Archive</a> </div> </li> <li class="nav-item"> <a class="nav-link" href="https://waset.org/page/support" title="Support">Support</a> </li> </ul> </div> </div> </nav> </div> </header> <main> <div class="container mt-4"> <div class="row"> <div class="col-md-9 mx-auto"> <form 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="laser doppler velocimeter"> <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> 952</div> </div> </div> </div> <h1 class="mt-3 mb-3 text-center" style="font-size:1.6rem;">Search results for: laser doppler velocimeter</h1> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">952</span> Cold Model Experimental Research on Particle Velocity Distribution in Gas-Solid Circulating Fluidized Bed for Methanol-To-Olefins Process</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Yongzheng%20Li">Yongzheng Li</a>, <a href="https://publications.waset.org/abstracts/search?q=Hongfang%20Ma"> Hongfang Ma</a>, <a href="https://publications.waset.org/abstracts/search?q=Qiwen%20Sun"> Qiwen Sun</a>, <a href="https://publications.waset.org/abstracts/search?q=Haitao%20Zhang"> Haitao Zhang</a>, <a href="https://publications.waset.org/abstracts/search?q=Weiyong%20Ying"> Weiyong Ying</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Radial profiles of particle velocities were investigated in a 6.1 m tall methanol-to-olefins cold model experimental device using a TSI laser Doppler velocimeter. The measurement of axial levels was conducted in the full developed region. The effect of axial level on flow development was not obvious under the same operating condition. Superficial gas velocity and solid circulating rate had significant influence on particle velocity in the center region of the riser. Besides, comparisons between upward, downward and average particle velocity were conducted. The average particle velocity was close to upward velocity and higher than downward velocity in radial locations except the wall region of riser. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=circulating%20fluidized%20bed" title="circulating fluidized bed">circulating fluidized bed</a>, <a href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20velocimeter" title=" laser doppler velocimeter"> laser doppler velocimeter</a>, <a href="https://publications.waset.org/abstracts/search?q=particle%20velocity" title=" particle velocity"> particle velocity</a>, <a href="https://publications.waset.org/abstracts/search?q=radial%20profile" title=" radial profile"> radial profile</a> </p> <a href="https://publications.waset.org/abstracts/25000/cold-model-experimental-research-on-particle-velocity-distribution-in-gas-solid-circulating-fluidized-bed-for-methanol-to-olefins-process" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/25000.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">370</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">951</span> Despiking of Turbulent Flow Data in Gravel Bed Stream </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ratul%20Das">Ratul Das</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The present experimental study insights the decontamination of instantaneous velocity fluctuations captured by Acoustic Doppler Velocimeter (ADV) in gravel-bed streams to ascertain near-bed turbulence for low Reynolds number. The interference between incidental and reflected pulses produce spikes in the ADV data especially in the near-bed flow zone and therefore filtering the data are very essential. Nortek’s Vectrino four-receiver ADV probe was used to capture the instantaneous three-dimensional velocity fluctuations over a non-cohesive bed. A spike removal algorithm based on the acceleration threshold method was applied to note the bed roughness and its influence on velocity fluctuations and velocity power spectra in the carrier fluid. The velocity power spectra of despiked signals with a best combination of velocity threshold (VT) and acceleration threshold (AT) are proposed which ascertained velocity power spectra a satisfactory fit with the Kolmogorov “–5/3 scaling-law” in the inertial sub-range. Also, velocity distributions below the roughness crest level fairly follows a third-degree polynomial series. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=acoustic%20doppler%20velocimeter" title="acoustic doppler velocimeter">acoustic doppler velocimeter</a>, <a href="https://publications.waset.org/abstracts/search?q=gravel-bed" title=" gravel-bed"> gravel-bed</a>, <a href="https://publications.waset.org/abstracts/search?q=spike%20removal" title=" spike removal"> spike removal</a>, <a href="https://publications.waset.org/abstracts/search?q=reynolds%20shear%20stress" title=" reynolds shear stress"> reynolds shear stress</a>, <a href="https://publications.waset.org/abstracts/search?q=near-bed%20turbulence" title=" near-bed turbulence"> near-bed turbulence</a>, <a href="https://publications.waset.org/abstracts/search?q=velocity%20power%20spectra" title=" velocity power spectra"> velocity power spectra</a> </p> <a href="https://publications.waset.org/abstracts/47047/despiking-of-turbulent-flow-data-in-gravel-bed-stream" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/47047.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">299</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">950</span> Diagnosis of Gingivitis Based on Correlations of Laser Doppler Data and Gingival Fluid Cytology</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=A.%20V.%20Belousov">A. V. Belousov</a>, <a href="https://publications.waset.org/abstracts/search?q=Yakushenko"> Yakushenko </a> </p> <p class="card-text"><strong>Abstract:</strong></p> One of the main problems of modern dentistry is development a reliable method to detect inflammation in the gums on the stages of diagnosis and assessment of treatment efficacy. We have proposed a method of gingival fluid intake, which successfully combines accessibility, excluding the impact of the annoying and damaging the gingival sulcus factors and provides reliable results (patent of RF№ 2342956 Method of gingival fluid intake). The objects of the study were students - volunteers of Dentistry Faculty numbering 75 people aged 20-21 years. Cellular composition of gingival fluid was studied using microscope "Olympus CX 31" (Japan) with the calculation of epithelial leukocyte index (ELI). Assessment of gingival micro circulation was performed using the apparatus «LAKK–01» (Lazma, Moscow). Cytological investigation noted the highly informative of epithelial leukocyte index (ELI), which demonstrated changes in the mechanisms of protection gums. The increase of ELI occurs during inhibition mechanisms of phagocytosis and activation of epithelial desquamation. The cytological data correlate with micro circulation indicators obtained by laser Doppler flowmetry. We have identified and confirmed the correlations between parameters laser Doppler flowmetry and data cytology gingival fluid in patients with gingivitis. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=gingivitis" title="gingivitis">gingivitis</a>, <a href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20flowmetry" title=" laser doppler flowmetry"> laser doppler flowmetry</a>, <a href="https://publications.waset.org/abstracts/search?q=gingival%20fluid%20cytology" title=" gingival fluid cytology"> gingival fluid cytology</a>, <a href="https://publications.waset.org/abstracts/search?q=epithelial%20leukocyte%20index%20%28ELI%29" title=" epithelial leukocyte index (ELI)"> epithelial leukocyte index (ELI)</a> </p> <a href="https://publications.waset.org/abstracts/22994/diagnosis-of-gingivitis-based-on-correlations-of-laser-doppler-data-and-gingival-fluid-cytology" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/22994.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">949</span> Turbulent Flow Characteristics and Bed Morphology around Circular Bridge Pier</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Pratik%20Acharya">Pratik Acharya</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Scour is the natural phenomenon brought about by erosive action of the flowing stream in alluvial channels. Frequent scouring around bridge piers may cause damage to the structures. In alluvial channels, a complex interaction between the streamflow and the bed particles results in scouring around piers. Thus, the study of characteristics of flow around piers can give sound knowledge about the scouring process. The present research has been done to investigate the turbulent flow characteristics around bridge piers and corresponding changes in bed morphology. Laboratory experiments were carried out in a tilting flume with a sand bed. The velocities around the pier are measured by Acoustic Doppler Velocimeter. Measurements show that at upstream of the pier velocity and Reynolds stresses are negative near the bed and near the free surface at downstream of the pier. At the downstream of the pier, Reynolds stresses changes rapidly due to the formation of wake vortices. Experimental results show that secondary currents are more predominant at the downstream of the pier. As the flowing stream hits the pier, the flow gets separated in the form of downflow along the face of the pier due to a strong pressure gradient and along the sides of the piers. Separation of flow around the pier leads to scour the bed material and develop the vortex. The downflow hits the bed and removes the bed material, which can be carried forward by the flow circulations along sides of the piers. Eroded bed material is deposited along the centerline at the rear side of the pier and produces hump in the downstream region. Initially, the rate of scouring is high and reduces gradually with increasing time. After a certain limit, equilibrium sets between the erosive capacity of the flowing stream and resistance to the motion by bed particles. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=acoustic%20doppler%20velocimeter" title="acoustic doppler velocimeter">acoustic doppler velocimeter</a>, <a href="https://publications.waset.org/abstracts/search?q=pier" title=" pier"> pier</a>, <a href="https://publications.waset.org/abstracts/search?q=Reynolds%20stress" title=" Reynolds stress"> Reynolds stress</a>, <a href="https://publications.waset.org/abstracts/search?q=scour%20depth" title=" scour depth"> scour depth</a>, <a href="https://publications.waset.org/abstracts/search?q=velocity" title=" velocity"> velocity</a> </p> <a href="https://publications.waset.org/abstracts/127886/turbulent-flow-characteristics-and-bed-morphology-around-circular-bridge-pier" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/127886.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">148</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">948</span> Velocity Distribution in Density Currents Flowing over Rough Beds</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Reza%20Nasrollahpour">Reza Nasrollahpour</a>, <a href="https://publications.waset.org/abstracts/search?q=Mohamad%20Hidayat%20Bin%20Jamal"> Mohamad Hidayat Bin Jamal</a>, <a href="https://publications.waset.org/abstracts/search?q=Zulhilmi%20Bin%20Ismail"> Zulhilmi Bin Ismail</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Density currents are generated when the fluid of one density is released into another fluid with a different density. These currents occur in a variety of natural and man-made environments, and this emphasises the importance of studying them. In most practical cases, the density currents flow over the surfaces which are not plane; however, there have been limited investigations in this regard. This study uses laboratory experiments to analyse the influence of bottom roughness on the velocity distribution within these dense underflows. The currents are analysed over a plane surface and three different configurations of beam-roughened beds. The velocity profiles are collected using Acoustic Doppler Velocimetry technique, and the distribution of velocity within these currents is formulated for the tested beds. The results indicate that the empirical power and Gaussian relations can describe the velocity distribution in the inner and outer regions of the profiles, respectively. Moreover, it is found that the bottom roughness is the primary controlling parameter in the inner region. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=density%20currents" title="density currents">density currents</a>, <a href="https://publications.waset.org/abstracts/search?q=velocity%20profiles" title=" velocity profiles"> velocity profiles</a>, <a href="https://publications.waset.org/abstracts/search?q=Acoustic%20Doppler%20Velocimeter" title=" Acoustic Doppler Velocimeter"> Acoustic Doppler Velocimeter</a>, <a href="https://publications.waset.org/abstracts/search?q=bed%20roughness" title=" bed roughness"> bed roughness</a> </p> <a href="https://publications.waset.org/abstracts/96631/velocity-distribution-in-density-currents-flowing-over-rough-beds" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/96631.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">185</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">947</span> Sympathetic Cooling of Antiprotons with Molecular Anions</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Sebastian%20Gerber">Sebastian Gerber</a>, <a href="https://publications.waset.org/abstracts/search?q=Julian%20Fesel"> Julian Fesel</a>, <a href="https://publications.waset.org/abstracts/search?q=Christian%20Zimmer"> Christian Zimmer</a>, <a href="https://publications.waset.org/abstracts/search?q=Pauline%20Yzombard"> Pauline Yzombard</a>, <a href="https://publications.waset.org/abstracts/search?q=Daniel%20Comparat"> Daniel Comparat</a>, <a href="https://publications.waset.org/abstracts/search?q=Michael%20Doser"> Michael Doser</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Molecular anions play a central role in a wide range of fields: from atmospheric and interstellar science, anionic superhalogens to the chemistry of highly correlated systems. However, up to now the synthesis of negative ions in a controlled manner at ultracold temperatures, relevant for the processes in which they are involved, is currently limited to a few Kelvin by supersonic beam expansion followed by resistive, buffer gas or electron cooling in cryogenic environments. We present a realistic scheme for laser cooling of C2- molecules to sub-Kelvin temperatures, which has so far only been achieved for a few neutral diatomic molecules. The generation of a pulsed source of C2- and subsequent laser cooling techniques of C2- molecules confined in a Penning trap are reviewed. Further, laser cooling of one anionic species would allow to sympathetically cool other molecular anions, electrons and antiprotons that are confined in the same trapping potential. In this presentation the status of the experiment and the feasibility of C2- sympathetic Doppler laser cooling, photo-detachment cooling and AC-Stark Sisyphus cooling will be reviewed. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=antiprotons" title="antiprotons">antiprotons</a>, <a href="https://publications.waset.org/abstracts/search?q=anions" title=" anions"> anions</a>, <a href="https://publications.waset.org/abstracts/search?q=cooling%20of%20ions%20and%20molecules" title=" cooling of ions and molecules"> cooling of ions and molecules</a>, <a href="https://publications.waset.org/abstracts/search?q=Doppler%20cooling" title=" Doppler cooling"> Doppler cooling</a>, <a href="https://publications.waset.org/abstracts/search?q=photo-detachment" title=" photo-detachment"> photo-detachment</a>, <a href="https://publications.waset.org/abstracts/search?q=penning%20trap" title=" penning trap"> penning trap</a>, <a href="https://publications.waset.org/abstracts/search?q=Sisyphus%20cooling" title=" Sisyphus cooling"> Sisyphus cooling</a>, <a href="https://publications.waset.org/abstracts/search?q=sympathetic%20cooling" title=" sympathetic cooling"> sympathetic cooling</a> </p> <a href="https://publications.waset.org/abstracts/60744/sympathetic-cooling-of-antiprotons-with-molecular-anions" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/60744.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">381</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">946</span> Laser Ultrasonic Imaging Based on Synthetic Aperture Focusing Technique Algorithm</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Sundara%20Subramanian%20Karuppasamy">Sundara Subramanian Karuppasamy</a>, <a href="https://publications.waset.org/abstracts/search?q=Che%20Hua%20Yang"> Che Hua Yang</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this work, the laser ultrasound technique has been used for analyzing and imaging the inner defects in metal blocks. To detect the defects in blocks, traditionally the researchers used piezoelectric transducers for the generation and reception of ultrasonic signals. These transducers can be configured into the sparse and phased array. But these two configurations have their drawbacks including the requirement of many transducers, time-consuming calculations, limited bandwidth, and provide confined image resolution. Here, we focus on the non-contact method for generating and receiving the ultrasound to examine the inner defects in aluminum blocks. A Q-switched pulsed laser has been used for the generation and the reception is done by using Laser Doppler Vibrometer (LDV). Based on the Doppler effect, LDV provides a rapid and high spatial resolution way for sensing ultrasonic waves. From the LDV, a series of scanning points are selected which serves as the phased array elements. The side-drilled hole of 10 mm diameter with a depth of 25 mm has been introduced and the defect is interrogated by the linear array of scanning points obtained from the LDV. With the aid of the Synthetic Aperture Focusing Technique (SAFT) algorithm, based on the time-shifting principle the inspected images are generated from the A-scan data acquired from the 1-D linear phased array elements. Thus the defect can be precisely detected with good resolution. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=laser%20ultrasonics" title="laser ultrasonics">laser ultrasonics</a>, <a href="https://publications.waset.org/abstracts/search?q=linear%20phased%20array" title=" linear phased array"> linear phased array</a>, <a href="https://publications.waset.org/abstracts/search?q=nondestructive%20testing" title=" nondestructive testing"> nondestructive testing</a>, <a href="https://publications.waset.org/abstracts/search?q=synthetic%20aperture%20focusing%20technique" title=" synthetic aperture focusing technique"> synthetic aperture focusing technique</a>, <a href="https://publications.waset.org/abstracts/search?q=ultrasonic%20imaging" title=" ultrasonic imaging"> ultrasonic imaging</a> </p> <a href="https://publications.waset.org/abstracts/130962/laser-ultrasonic-imaging-based-on-synthetic-aperture-focusing-technique-algorithm" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/130962.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">134</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">945</span> Radar-Based Classification of Pedestrian and Dog Using High-Resolution Raw Range-Doppler Signatures</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=C.%20Mayr">C. Mayr</a>, <a href="https://publications.waset.org/abstracts/search?q=J.%20Periya"> J. Periya</a>, <a href="https://publications.waset.org/abstracts/search?q=A.%20Kariminezhad"> A. Kariminezhad</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this paper, we developed a learning framework for the classification of vulnerable road users (VRU) by their range-Doppler signatures. The frequency-modulated continuous-wave (FMCW) radar raw data is first pre-processed to obtain robust object range-Doppler maps per coherent time interval. The complex-valued range-Doppler maps captured from our outdoor measurements are further fed into a convolutional neural network (CNN) to learn the classification. This CNN has gone through a hyperparameter optimization process for improved learning. By learning VRU range-Doppler signatures, the three classes 'pedestrian', 'dog', and 'noise' are classified with an average accuracy of almost 95%. Interestingly, this classification accuracy holds for a combined longitudinal and lateral object trajectories. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=machine%20learning" title="machine learning">machine learning</a>, <a href="https://publications.waset.org/abstracts/search?q=radar" title=" radar"> radar</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=autonomous%20driving" title=" autonomous driving"> autonomous driving</a> </p> <a href="https://publications.waset.org/abstracts/139166/radar-based-classification-of-pedestrian-and-dog-using-high-resolution-raw-range-doppler-signatures" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/139166.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">246</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">944</span> Laser-Hole Boring into Overdense Targets: A Detailed Study on Laser and Target Properties</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Florian%20Wagner">Florian Wagner</a>, <a href="https://publications.waset.org/abstracts/search?q=Christoph%20Schmidt"> Christoph Schmidt</a>, <a href="https://publications.waset.org/abstracts/search?q=Vincent%20Bagnoud"> Vincent Bagnoud</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Understanding the interaction of ultra-intense laser pulses with overcritical targets is of major interest for many applications such as laser-driven ion acceleration, fast ignition in the frame of inertial confinement fusion or high harmonic generation and the creation of attosecond pulses. One particular aspect of this interaction is the shift of the critical surface, where the laser pulse is stopped and the absorption is at maximum, due to the radiation pressure induced by the laser pulse, also referred to as laser hole boring. We investigate laser-hole boring experimentally by measuring the backscattered spectrum which is doppler-broadened because of the movement of the reflecting surface. Using the high-power, high-energy laser system PHELIX in Darmstadt, we gathered an extensive set of data for different laser intensities ranging from 10^18 W/cm2 to 10^21 W/cm2, two different levels of the nanosecond temporal contrast (10^6 vs. 10^11), elliptical and linear polarization and varying target configurations. In this contribution we discuss how the maximum velocity of the critical surface depends on these parameters. In particular we show that by increasing the temporal contrast the maximum hole boring velocity is decreased by more than a factor of three. Our experimental findings are backed by a basic analytical model based on momentum and mass conservation as well as particle in cell simulations. These results are of particular importance for fast ignition since they contribute to a better understanding of the transport of the ignitor pulse into the overdense region. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=laser-hole%20boring" title="laser-hole boring">laser-hole boring</a>, <a href="https://publications.waset.org/abstracts/search?q=interaction%20of%20ultra-intense%20lasers%20with%20overcritical%20targets" title=" interaction of ultra-intense lasers with overcritical targets"> interaction of ultra-intense lasers with overcritical targets</a>, <a href="https://publications.waset.org/abstracts/search?q=fast%20ignition" title=" fast ignition"> fast ignition</a>, <a href="https://publications.waset.org/abstracts/search?q=relativistic%20laser%20motter%20interaction" title=" relativistic laser motter interaction"> relativistic laser motter interaction</a> </p> <a href="https://publications.waset.org/abstracts/45345/laser-hole-boring-into-overdense-targets-a-detailed-study-on-laser-and-target-properties" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/45345.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">405</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">943</span> Innovative Technologies Functional Methods of Dental Research</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Sergey%20N.%20Ermoliev">Sergey N. Ermoliev</a>, <a href="https://publications.waset.org/abstracts/search?q=Margarita%20A.%20Belousova"> Margarita A. Belousova</a>, <a href="https://publications.waset.org/abstracts/search?q=Aida%20D.%20Goncharenko"> Aida D. Goncharenko</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Application of the diagnostic complex of highly informative functional methods (electromyography, reodentography, laser Doppler flowmetry, reoperiodontography, vital computer capillaroscopy, optical tissue oximetry, laser fluorescence diagnosis) allows to perform a multifactorial analysis of the dental status and to prescribe complex etiopathogenetic treatment. Introduction. It is necessary to create a complex of innovative highly informative and safe functional diagnostic methods for improvement of the quality of patient treatment by the early detection of stomatologic diseases. The purpose of the present study was to investigate the etiology and pathogenesis of functional disorders identified in the pathology of hard tissue, dental pulp, periodontal, oral mucosa and chewing function, and the creation of new approaches to the diagnosis of dental diseases. Material and methods. 172 patients were examined. Density of hard tissues of the teeth and jaw bone was studied by intraoral ultrasonic densitometry (USD). Electromyographic activity of masticatory muscles was assessed by electromyography (EMG). Functional state of dental pulp vessels assessed by reodentography (RDG) and laser Doppler flowmetry (LDF). Reoperiodontography method (RPG) studied regional blood flow in the periodontal tissues. Microcirculatory vascular periodontal studied by vital computer capillaroscopy (VCC) and laser Doppler flowmetry (LDF). The metabolic level of the mucous membrane was determined by optical tissue oximetry (OTO) and laser fluorescence diagnosis (LFD). Results and discussion. The results obtained revealed changes in mineral density of hard tissues of the teeth and jaw bone, the bioelectric activity of masticatory muscles, regional blood flow and microcirculation in the dental pulp and periodontal tissues. LDF and OTO methods estimated fluctuations of saturation level and oxygen transport in microvasculature of periodontal tissues. With LFD identified changes in the concentration of enzymes (nicotinamide, flavins, lipofuscin, porphyrins) involved in metabolic processes Conclusion. Our preliminary results confirmed feasibility and safety the of intraoral ultrasound densitometry technique in the density of bone tissue of periodontium. Conclusion. Application of the diagnostic complex of above mentioned highly informative functional methods allows to perform a multifactorial analysis of the dental status and to prescribe complex etiopathogenetic treatment. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=electromyography%20%28EMG%29" title="electromyography (EMG)">electromyography (EMG)</a>, <a href="https://publications.waset.org/abstracts/search?q=reodentography%20%28RDG%29" title=" reodentography (RDG)"> reodentography (RDG)</a>, <a href="https://publications.waset.org/abstracts/search?q=laser%20Doppler%20flowmetry%20%28LDF%29" title=" laser Doppler flowmetry (LDF)"> laser Doppler flowmetry (LDF)</a>, <a href="https://publications.waset.org/abstracts/search?q=reoperiodontography%20method%20%28RPG%29" title=" reoperiodontography method (RPG)"> reoperiodontography method (RPG)</a>, <a href="https://publications.waset.org/abstracts/search?q=vital%20computer%20capillaroscopy%20%28VCC%29" title=" vital computer capillaroscopy (VCC)"> vital computer capillaroscopy (VCC)</a>, <a href="https://publications.waset.org/abstracts/search?q=optical%20tissue%20oximetry%20%28OTO%29" title=" optical tissue oximetry (OTO)"> optical tissue oximetry (OTO)</a>, <a href="https://publications.waset.org/abstracts/search?q=laser%20fluorescence%20diagnosis%20%28LFD%29" title=" laser fluorescence diagnosis (LFD)"> laser fluorescence diagnosis (LFD)</a> </p> <a href="https://publications.waset.org/abstracts/21954/innovative-technologies-functional-methods-of-dental-research" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/21954.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">280</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">942</span> Experimental and Numerical Study of Thermal Effects in Variable Density Turbulent Jets </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=DRIS%20Mohammed%20El-Amine">DRIS Mohammed El-Amine</a>, <a href="https://publications.waset.org/abstracts/search?q=BOUNIF%20Abdelhamid"> BOUNIF Abdelhamid</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper considers an experimental and numerical investigation of variable density in axisymmetric turbulent free jets. Special attention is paid to the study of the scalar dissipation rate. In this case, dynamic field equations are coupled to scalar field equations by the density which can vary by the thermal effect (jet heating). The numerical investigation is based on the first and second order turbulence models. For the discretization of the equations system characterizing the flow, the finite volume method described by Patankar (1980) was used. The experimental study was conducted in order to evaluate dynamical characteristics of a heated axisymmetric air flow using the Laser Doppler Anemometer (LDA) which is a very accurate optical measurement method. Experimental and numerical results are compared and discussed. This comparison do not show large difference and the results obtained are in general satisfactory. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Scalar%20dissipation%20rate" title="Scalar dissipation rate">Scalar dissipation rate</a>, <a href="https://publications.waset.org/abstracts/search?q=thermal%20effects" title=" thermal effects"> thermal effects</a>, <a href="https://publications.waset.org/abstracts/search?q=turbulent%20axisymmetric%20jets" title=" turbulent axisymmetric jets"> turbulent axisymmetric jets</a>, <a href="https://publications.waset.org/abstracts/search?q=second%20order%20modelling" title=" second order modelling"> second order modelling</a>, <a href="https://publications.waset.org/abstracts/search?q=Velocimetry%20Laser%20Doppler." title=" Velocimetry Laser Doppler."> Velocimetry Laser Doppler.</a> </p> <a href="https://publications.waset.org/abstracts/19513/experimental-and-numerical-study-of-thermal-effects-in-variable-density-turbulent-jets" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/19513.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">450</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">941</span> Frequency Modulation Continuous Wave Radar Human Fall Detection Based on Time-Varying Range-Doppler Features</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Xiang%20Yu">Xiang Yu</a>, <a href="https://publications.waset.org/abstracts/search?q=Chuntao%20Feng"> Chuntao Feng</a>, <a href="https://publications.waset.org/abstracts/search?q=Lu%20Yang"> Lu Yang</a>, <a href="https://publications.waset.org/abstracts/search?q=Meiyang%20Song"> Meiyang Song</a>, <a href="https://publications.waset.org/abstracts/search?q=Wenhao%20Zhou"> Wenhao Zhou</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The existing two-dimensional micro-Doppler features extraction ignores the correlation information between the spatial and temporal dimension features. For the range-Doppler map, the time dimension is introduced, and a frequency modulation continuous wave (FMCW) radar human fall detection algorithm based on time-varying range-Doppler features is proposed. Firstly, the range-Doppler sequence maps are generated from the echo signals of the continuous motion of the human body collected by the radar. Then the three-dimensional data cube composed of multiple frames of range-Doppler maps is input into the three-dimensional Convolutional Neural Network (3D CNN). The spatial and temporal features of time-varying range-Doppler are extracted by the convolution layer and pool layer at the same time. Finally, the extracted spatial and temporal features are input into the fully connected layer for classification. The experimental results show that the proposed fall detection algorithm has a detection accuracy of 95.66%. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=FMCW%20radar" title="FMCW radar">FMCW radar</a>, <a href="https://publications.waset.org/abstracts/search?q=fall%20detection" title=" fall detection"> fall detection</a>, <a href="https://publications.waset.org/abstracts/search?q=3D%20CNN" title=" 3D CNN"> 3D CNN</a>, <a href="https://publications.waset.org/abstracts/search?q=time-varying%20range-doppler%20features" title=" time-varying range-doppler features"> time-varying range-doppler features</a> </p> <a href="https://publications.waset.org/abstracts/150637/frequency-modulation-continuous-wave-radar-human-fall-detection-based-on-time-varying-range-doppler-features" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/150637.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">123</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">940</span> Investigation of the Unbiased Characteristic of Doppler Frequency to Different Antenna Array Geometries</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Somayeh%20Komeylian">Somayeh Komeylian</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Array signal processing techniques have been recently developing in a variety application of the performance enhancement of receivers by refraining the power of jamming and interference signals. In this scenario, biases induced to the antenna array receiver degrade significantly the accurate estimation of the carrier phase. Owing to the integration of frequency becomes the carrier phase, we have obtained the unbiased doppler frequency for the high precision estimation of carrier phase. The unbiased characteristic of Doppler frequency to the power jamming and the other interference signals allows achieving the highly accurate estimation of phase carrier. In this study, we have rigorously investigated the unbiased characteristic of Doppler frequency to the variation of the antenna array geometries. The simulation results have efficiently verified that the Doppler frequency remains also unbiased and accurate to the variation of antenna array geometries. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=array%20signal%20processing" title="array signal processing">array signal processing</a>, <a href="https://publications.waset.org/abstracts/search?q=unbiased%20doppler%20frequency" title=" unbiased doppler frequency"> unbiased doppler frequency</a>, <a href="https://publications.waset.org/abstracts/search?q=GNSS" title=" GNSS"> GNSS</a>, <a href="https://publications.waset.org/abstracts/search?q=carrier%20phase" title=" carrier phase"> carrier phase</a>, <a href="https://publications.waset.org/abstracts/search?q=and%20slowly%20fluctuating%20point%20target" title=" and slowly fluctuating point target"> and slowly fluctuating point target</a> </p> <a href="https://publications.waset.org/abstracts/129148/investigation-of-the-unbiased-characteristic-of-doppler-frequency-to-different-antenna-array-geometries" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/129148.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">159</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">939</span> Clinical Parameters Response to Low Level Laser Versus Monochromatic Near Infrared Photo Energy in Diabetic Patient with Peripheral Neuropathy</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Abeer%20Ahmed%20Abdehameed">Abeer Ahmed Abdehameed </a> </p> <p class="card-text"><strong>Abstract:</strong></p> Background: Diabetic sensorimotor polyneuropathy (DSP) is one of the most common micro vascular complications of type 2 diabetes. Loss of sensation is thought to contribute to lake of static and dynamic stability and increased risk of falling. Purpose: The purpose of this study was to compare the effects of low level laser (LLL) and monochromatic near infrared photo energy (MIRE) on pain , cutaneous sensation, static stability and index of lower limb blood flow in diabetic with peripheral neuropathy. Methods: Forty subjects with diabetic peripheral neuropathy were recruited for study. They were divided into two groups: The ( MIRE) group that included (20) patients and (LLL) group included (20) patients. All patients in the study had been subjected to various physical assessment procedures including pain, cutaneous sensation, Doppler flow meter and static stability assessments. The baseline measurements were followed by treatment sessions that conducted twice a week for 6 successive weeks. Results: The statistical analysis of the data had revealed significant improvement of the pain in both groups, with significant improvement in cutaneous sensation and static balance in (MIRE) group compared to (LLL) group; on the other hand results showed no significant differences on lower limb blood flow in both groups. Conclusion: Low level laser and monochromatic near infrared therapy can improve painful symptoms in patients with diabetic neuropathy. On the other hand (MIRE) is useful in improving cutaneous sensation and static stability in patients with diabetic neuropathy. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=diabetic%20neuropathy" title="diabetic neuropathy">diabetic neuropathy</a>, <a href="https://publications.waset.org/abstracts/search?q=doppler%20flow%20meter" title=" doppler flow meter"> doppler flow meter</a>, <a href="https://publications.waset.org/abstracts/search?q=low%20level%20laser" title=" low level laser"> low level laser</a>, <a href="https://publications.waset.org/abstracts/search?q=monochromatic%20near%20infrared%20photo%20energy" title=" monochromatic near infrared photo energy"> monochromatic near infrared photo energy</a> </p> <a href="https://publications.waset.org/abstracts/31260/clinical-parameters-response-to-low-level-laser-versus-monochromatic-near-infrared-photo-energy-in-diabetic-patient-with-peripheral-neuropathy" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/31260.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">314</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">938</span> Distant Speech Recognition Using Laser Doppler Vibrometer</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Yunbin%20Deng">Yunbin Deng</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Most existing applications of automatic speech recognition relies on cooperative subjects at a short distance to a microphone. Standoff speech recognition using microphone arrays can extend the subject to sensor distance somewhat, but it is still limited to only a few feet. As such, most deployed applications of standoff speech recognitions are limited to indoor use at short range. Moreover, these applications require air passway between the subject and the sensor to achieve reasonable signal to noise ratio. This study reports long range (50 feet) automatic speech recognition experiments using a Laser Doppler Vibrometer (LDV) sensor. This study shows that the LDV sensor modality can extend the speech acquisition standoff distance far beyond microphone arrays to hundreds of feet. In addition, LDV enables 'listening' through the windows for uncooperative subjects. This enables new capabilities in automatic audio and speech intelligence, surveillance, and reconnaissance (ISR) for law enforcement, homeland security and counter terrorism applications. The Polytec LDV model OFV-505 is used in this study. To investigate the impact of different vibrating materials, five parallel LDV speech corpora, each consisting of 630 speakers, are collected from the vibrations of a glass window, a metal plate, a plastic box, a wood slate, and a concrete wall. These are the common materials the application could encounter in a daily life. These data were compared with the microphone counterpart to manifest the impact of various materials on the spectrum of the LDV speech signal. State of the art deep neural network modeling approaches is used to conduct continuous speaker independent speech recognition on these LDV speech datasets. Preliminary phoneme recognition results using time-delay neural network, bi-directional long short term memory, and model fusion shows great promise of using LDV for long range speech recognition. To author’s best knowledge, this is the first time an LDV is reported for long distance speech recognition application. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=covert%20speech%20acquisition" title="covert speech acquisition">covert speech acquisition</a>, <a href="https://publications.waset.org/abstracts/search?q=distant%20speech%20recognition" title=" distant speech recognition"> distant speech recognition</a>, <a href="https://publications.waset.org/abstracts/search?q=DSR" title=" DSR"> DSR</a>, <a href="https://publications.waset.org/abstracts/search?q=laser%20Doppler%20vibrometer" title=" laser Doppler vibrometer"> laser Doppler vibrometer</a>, <a href="https://publications.waset.org/abstracts/search?q=LDV" title=" LDV"> LDV</a>, <a href="https://publications.waset.org/abstracts/search?q=speech%20intelligence%20surveillance%20and%20reconnaissance" title=" speech intelligence surveillance and reconnaissance"> speech intelligence surveillance and reconnaissance</a>, <a href="https://publications.waset.org/abstracts/search?q=ISR" title=" ISR"> ISR</a> </p> <a href="https://publications.waset.org/abstracts/99091/distant-speech-recognition-using-laser-doppler-vibrometer" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/99091.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">179</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">937</span> Airborne SAR Data Analysis for Impact of Doppler Centroid on Image Quality and Registration Accuracy</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Chhabi%20Nigam">Chhabi Nigam</a>, <a href="https://publications.waset.org/abstracts/search?q=S.%20Ramakrishnan"> S. Ramakrishnan</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper brings out the analysis of the airborne Synthetic Aperture Radar (SAR) data to study the impact of Doppler centroid on Image quality and geocoding accuracy from the perspective of Stripmap mode of data acquisition. Although in Stripmap mode of data acquisition radar beam points at 90 degrees broad side (side looking), shift in the Doppler centroid is invariable due to platform motion. In-accurate estimation of Doppler centroid leads to poor image quality and image miss-registration. The effect of Doppler centroid is analyzed in this paper using multiple sets of data collected from airborne platform. Occurrences of ghost (ambiguous) targets and their power levels have been analyzed that impacts appropriate choice of PRF. Effect of aircraft attitudes (roll, pitch and yaw) on the Doppler centroid is also analyzed with the collected data sets. Various stages of the RDA (Range Doppler Algorithm) algorithm used for image formation in Stripmap mode, range compression, Doppler centroid estimation, azimuth compression, range cell migration correction are analyzed to find the performance limits and the dependence of the imaging geometry on the final image. The ability of Doppler centroid estimation to enhance the imaging accuracy for registration are also illustrated in this paper. The paper also tries to bring out the processing of low squint SAR data, the challenges and the performance limits imposed by the imaging geometry and the platform dynamics on the final image quality metrics. Finally, the effect on various terrain types, including land, water and bright scatters is also presented. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=ambiguous%20target" title="ambiguous target">ambiguous target</a>, <a href="https://publications.waset.org/abstracts/search?q=Doppler%20Centroid" title=" Doppler Centroid"> Doppler Centroid</a>, <a href="https://publications.waset.org/abstracts/search?q=image%20registration" title=" image registration"> image registration</a>, <a href="https://publications.waset.org/abstracts/search?q=Airborne%20SAR" title=" Airborne SAR"> Airborne SAR</a> </p> <a href="https://publications.waset.org/abstracts/62254/airborne-sar-data-analysis-for-impact-of-doppler-centroid-on-image-quality-and-registration-accuracy" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/62254.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">218</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">936</span> The Effect of Inlet Baffle Position in Improving the Efficiency of Oil and Water Gravity Separator Tanks </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Haitham%20A.%20Hussein">Haitham A. Hussein</a>, <a href="https://publications.waset.org/abstracts/search?q=Rozi%20Abdullah"> Rozi Abdullah</a>, <a href="https://publications.waset.org/abstracts/search?q=Issa%20Saket"> Issa Saket</a>, <a href="https://publications.waset.org/abstracts/search?q=Md.%20Azlin"> Md. Azlin</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The gravitational effect has been extensively applied to separate oil from water in water and wastewater treatment systems. The maximum oil globules removal efficiency is improved by obtaining the best flow uniformity in separator tanks. This study used 2D computational fluid dynamics (CFD) to investigate the effect of different inlet baffle positions inside the separator tank. Laboratory experiment has been conducted, and the measured velocity fields which were by Nortek Acoustic Doppler Velocimeter (ADV) are used to verify the CFD model. Computational investigation results indicated that the construction of an inlet baffle in a suitable location provides the minimum recirculation zone volume, creates the best flow uniformity, and dissipates kinetic energy in the oil and water separator tank. Useful formulas were predicted to design the oil and water separator tanks geometry based on an experimental model. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=oil%2Fwater%20separator%20tanks" title="oil/water separator tanks">oil/water separator tanks</a>, <a href="https://publications.waset.org/abstracts/search?q=inlet%20baffles" title=" inlet baffles"> inlet baffles</a>, <a href="https://publications.waset.org/abstracts/search?q=CFD" title=" CFD"> CFD</a>, <a href="https://publications.waset.org/abstracts/search?q=VOF" title=" VOF"> VOF</a> </p> <a href="https://publications.waset.org/abstracts/52725/the-effect-of-inlet-baffle-position-in-improving-the-efficiency-of-oil-and-water-gravity-separator-tanks" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/52725.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">367</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">935</span> Wobbled Laser Beam Welding for Macro-to Micro-Fabrication Process</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Farzad%20Vakili-Farahani">Farzad Vakili-Farahani</a>, <a href="https://publications.waset.org/abstracts/search?q=Joern%20Lungershausen"> Joern Lungershausen</a>, <a href="https://publications.waset.org/abstracts/search?q=Kilian%20Wasmer"> Kilian Wasmer</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Wobbled laser beam welding, fast oscillations of a tiny laser beam within a designed path (weld geometry) during the laser pulse illumination, opens new possibilities to improve the marco-to micro-manufacturing process. The present work introduces the wobbled laser beam welding as a robust welding strategy for improving macro-to micro-fabrication process, e.g., the laser processing for gap-bridging and packaging industry. The typical requisites and relevant equipment for the development of a wobbled laser processing unit are addressed, including a suitable laser source, light delivery system, optics, proper beam deflection system and the design geometry. In addition, experiments have been carried out on titanium plate to compare the results of wobbled laser welding with conventional pulsed laser welding. As compared to the pulsed laser welding, the wobbled laser welding offers a much greater fusion area (i.e. additional molten material) while minimizing the HAZ and provides a better confinement of the material microstructural changes. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=wobbled%20laser%20beam%20welding" title="wobbled laser beam welding">wobbled laser beam welding</a>, <a href="https://publications.waset.org/abstracts/search?q=wobbling%20function" title=" wobbling function"> wobbling function</a>, <a href="https://publications.waset.org/abstracts/search?q=beam%20oscillation" title=" beam oscillation"> beam oscillation</a>, <a href="https://publications.waset.org/abstracts/search?q=micro%20welding" title=" micro welding"> micro welding</a> </p> <a href="https://publications.waset.org/abstracts/56603/wobbled-laser-beam-welding-for-macro-to-micro-fabrication-process" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/56603.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">934</span> Laser Beam Bending via Lenses</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Remzi%20Yildirim">Remzi Yildirim</a>, <a href="https://publications.waset.org/abstracts/search?q=Fatih.%20V.%20%C3%87elebi"> Fatih. V. Çelebi</a>, <a href="https://publications.waset.org/abstracts/search?q=H.%20Haldun%20G%C3%B6kta%C5%9F"> H. Haldun Göktaş</a>, <a href="https://publications.waset.org/abstracts/search?q=A.%20Behzat%20%C5%9Eahin"> A. Behzat Şahin</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This study is about a single component cylindrical structured lens with gradient curve which we used for bending laser beams. It operates under atmospheric conditions and bends the laser beam independent of temperature, pressure, polarity, polarization, magnetic field, electric field, radioactivity, and gravity. A single piece cylindrical lens that can bend laser beams is invented. Lenses are made of transparent, tinted or colored glasses and used for undermining or absorbing the energy of the laser beams. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=laser" title="laser">laser</a>, <a href="https://publications.waset.org/abstracts/search?q=bending" title=" bending"> bending</a>, <a href="https://publications.waset.org/abstracts/search?q=lens" title=" lens"> lens</a>, <a href="https://publications.waset.org/abstracts/search?q=light" title=" light"> light</a>, <a href="https://publications.waset.org/abstracts/search?q=nonlinear%20optics" title=" nonlinear optics"> nonlinear optics</a> </p> <a href="https://publications.waset.org/abstracts/22254/laser-beam-bending-via-lenses" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/22254.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">488</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">933</span> Laser Light Bending via Lenses</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Remzi%20Yildirim">Remzi Yildirim</a>, <a href="https://publications.waset.org/abstracts/search?q=Fatih%20V.%20%C3%87elebi"> Fatih V. Çelebi</a>, <a href="https://publications.waset.org/abstracts/search?q=H.%20Haldun%20G%C3%B6kta%C5%9F"> H. Haldun Göktaş</a>, <a href="https://publications.waset.org/abstracts/search?q=A.%20Behzat%20%C5%9Eahin"> A. Behzat Şahin</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This study is about a single component cylindrical structured lens with gradient curve which we used for bending laser beams. It operates under atmospheric conditions and bends the laser beam independent of temperature, pressure, polarity, polarization, magnetic field, electric field, radioactivity, and gravity. A single piece cylindrical lens that can bend laser beams is invented. Lenses are made of transparent, tinted or colored glasses and used for undermining or absorbing the energy of the laser beams. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=laser" title="laser">laser</a>, <a href="https://publications.waset.org/abstracts/search?q=bending" title=" bending"> bending</a>, <a href="https://publications.waset.org/abstracts/search?q=lens" title=" lens"> lens</a>, <a href="https://publications.waset.org/abstracts/search?q=light" title=" light"> light</a>, <a href="https://publications.waset.org/abstracts/search?q=nonlinear%20optics" title=" nonlinear optics"> nonlinear optics</a> </p> <a href="https://publications.waset.org/abstracts/22251/laser-light-bending-via-lenses" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/22251.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">703</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">932</span> Experimental and Computational Investigations of Baffle Position Effects on ‎the Performance of Oil and Water Separator Tanks</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Haitham%20A.%20Hussein">Haitham A. Hussein</a>, <a href="https://publications.waset.org/abstracts/search?q=Rozi%20Abdullah%E2%80%8F%E2%80%8E"> Rozi Abdullah‏‎</a>, <a href="https://publications.waset.org/abstracts/search?q=Md%20Azlin%20Md%20Said%20%E2%80%8E"> Md Azlin Md Said ‎</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Gravity separator tanks are used to separate oil from water in treatment units. Achieving the best flow ‎uniformity in a separator tank will improve the maximum removal efficiency of oil globules from water. ‎In this study, the effect on hydraulic performance of different baffle structure positions inside a tank ‎was investigated. Experimental data and 2D computation fluid dynamics were used for analysis. In the ‎numerical model, two-phase flow (drift flux model) was used to validate one-phase flow. For ‎laboratory measurements, the velocity fields were measured using an acoustic Doppler velocimeter. The ‎measurements were compared with the result of the computational model. The results of the ‎experimental and computational simulations indicate that the best location of a baffle structure is ‎achieved when the standard deviation of the velocity profile and the volume of the circulation zone ‎inside the tank are minimized.‎ <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=gravity%20separator%20tanks" title="gravity separator tanks">gravity separator tanks</a>, <a href="https://publications.waset.org/abstracts/search?q=CFD" title=" CFD"> CFD</a>, <a href="https://publications.waset.org/abstracts/search?q=baffle%20position" title=" baffle position"> baffle position</a>, <a href="https://publications.waset.org/abstracts/search?q=two%20phase%20flow" title=" two phase flow"> two phase flow</a>, <a href="https://publications.waset.org/abstracts/search?q=ADV" title=" ADV"> ADV</a>, <a href="https://publications.waset.org/abstracts/search?q=oil%20droplet" title=" oil droplet"> oil droplet</a> </p> <a href="https://publications.waset.org/abstracts/13318/experimental-and-computational-investigations-of-baffle-position-effects-on-the-performance-of-oil-and-water-separator-tanks" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/13318.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">931</span> Hole Characteristics of Percussion and Single Pulse Laser-Incised Radiata Pine and the Effects of Wood Anatomy on Laser-Incision</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Subhasisa%20Nath">Subhasisa Nath</a>, <a href="https://publications.waset.org/abstracts/search?q=David%20Waugh"> David Waugh</a>, <a href="https://publications.waset.org/abstracts/search?q=Graham%20Ormondroyd"> Graham Ormondroyd</a>, <a href="https://publications.waset.org/abstracts/search?q=Morwenna%20Spear"> Morwenna Spear</a>, <a href="https://publications.waset.org/abstracts/search?q=Andy%20Pitman"> Andy Pitman</a>, <a href="https://publications.waset.org/abstracts/search?q=Paul%20Mason"> Paul Mason</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Wood is one of the most sustainable and environmentally favourable materials and is chemically treated in timber industries to maximise durability. To increase the chemical preservative uptake and retention by the wood, current limiting incision technologies are commonly used. This work reports the effects of single pulse CO2 laser-incision and frequency tripled Nd:YAG percussion laser-incision on the characteristics of laser-incised holes in the Radiata Pine. The laser-incision studies were based on changing laser wavelengths, energies and focal planes to conclude on an optimised combination for the laser-incision of Radiata Pine. The laser pulse duration had a dominant effect over laser power in controlling hole aspect ratio in CO2 laser-incision. A maximum depth of ~ 30 mm was measured with a laser power output of 170 W and a pulse duration of 80 ms. However, increased laser power led to increased carbonisation of holes. The carbonisation effect was reduced during laser-incision in the ultra-violet (UV) regime. Deposition of a foamy phase on the laser-incised hole wall was evident irrespective of laser radiation wavelength and energy. A maximum hole depth of ~20 mm was measured in the percussion laser-incision in the UV regime (355 nm) with a pulse energy of 320 mJ. The radial and tangential faces had a significant effect on laser-incision efficiency for all laser wavelengths. The laser-incised hole shapes and circularities were affected by the wood anatomy (earlywoods and latewoods in the structure). Subsequently, the mechanism of laser-incision is proposed by analysing the internal structure of laser-incised holes. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=CO2%20Laser" title="CO2 Laser">CO2 Laser</a>, <a href="https://publications.waset.org/abstracts/search?q=Nd%3A%20YAG%20laser" title=" Nd: YAG laser"> Nd: YAG laser</a>, <a href="https://publications.waset.org/abstracts/search?q=incision" title=" incision"> incision</a>, <a href="https://publications.waset.org/abstracts/search?q=drilling" title=" drilling"> drilling</a>, <a href="https://publications.waset.org/abstracts/search?q=wood" title=" wood"> wood</a>, <a href="https://publications.waset.org/abstracts/search?q=hole%20characteristics" title=" hole characteristics"> hole characteristics</a> </p> <a href="https://publications.waset.org/abstracts/138450/hole-characteristics-of-percussion-and-single-pulse-laser-incised-radiata-pine-and-the-effects-of-wood-anatomy-on-laser-incision" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/138450.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">930</span> Enhancing of Laser Imaging by Using Ultrasound Effect</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Hayder%20Raad%20Hafuze">Hayder Raad Hafuze</a>, <a href="https://publications.waset.org/abstracts/search?q=Munqith%20Saleem%20Dawood"> Munqith Saleem Dawood</a>, <a href="https://publications.waset.org/abstracts/search?q=Jamal%20Abdul%20Jabbar"> Jamal Abdul Jabbar </a> </p> <p class="card-text"><strong>Abstract:</strong></p> The effect of using both ultrasounds with laser in medical imaging of the biological tissue has been studied in this paper. Different wave lengths of incident laser light (405 nm, 532 nm, 650 nm, 808 nm and 1064 nm) were used with different ultrasound frequencies (1MHz and 3.3MHz). The results showed that, the change of acoustic intensity enhance the laser penetration of the tissue for different thickness. The existence of the ideal Raman-Nath diffraction pattern were investigated in terms of phase delay and incident angle. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=tissue" title="tissue">tissue</a>, <a href="https://publications.waset.org/abstracts/search?q=laser" title=" laser"> laser</a>, <a href="https://publications.waset.org/abstracts/search?q=ultrasound" title=" ultrasound"> ultrasound</a>, <a href="https://publications.waset.org/abstracts/search?q=effect" title=" effect"> effect</a>, <a href="https://publications.waset.org/abstracts/search?q=imaging" title=" imaging "> imaging </a> </p> <a href="https://publications.waset.org/abstracts/45517/enhancing-of-laser-imaging-by-using-ultrasound-effect" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/45517.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">433</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">929</span> Hydrodynamic Characterisation of a Hydraulic Flume with Sheared Flow</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Daniel%20Rowe">Daniel Rowe</a>, <a href="https://publications.waset.org/abstracts/search?q=Christopher%20R.%20Vogel"> Christopher R. Vogel</a>, <a href="https://publications.waset.org/abstracts/search?q=Richard%20H.%20J.%20Willden"> Richard H. J. Willden</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The University of Oxford’s recirculating water flume is a combined wave and current test tank with a 1 m depth, 1.1 m width, and 10 m long working section, and is capable of flow speeds up to 1 ms−1 . This study documents the hydrodynamic characteristics of the facility in preparation for experimental testing of horizontal axis tidal stream turbine models. The turbine to be tested has a rotor diameter of 0.6 m and is a modified version of one of two model-scale turbines tested in previous experimental campaigns. An Acoustic Doppler Velocimeter (ADV) was used to measure the flow at high temporal resolution at various locations throughout the flume, enabling the spatial uniformity and turbulence flow parameters to be investigated. The mean velocity profiles exhibited high levels of spatial uniformity at the design speed of the flume, 0.6 ms−1 , with variations in the three-dimensional velocity components on the order of ±1% at the 95% confidence level, along with a modest streamwise acceleration through the measurement domain, a target 5 m working section of the flume. A high degree of uniformity was also apparent for the turbulence intensity, with values ranging between 1-2% across the intended swept area of the turbine rotor. The integral scales of turbulence exhibited a far higher degree of variation throughout the water column, particularly in the streamwise and vertical scales. This behaviour is believed to be due to the high signal noise content leading to decorrelation in the sampling records. To achieve more realistic levels of vertical velocity shear in the flume, a simple procedure to practically generate target vertical shear profiles in open-channel flows is described. Here, the authors arranged a series of non-uniformly spaced parallel bars placed across the width of the flume and normal to the onset flow. By adjusting the resistance grading across the height of the working section, the downstream profiles could be modified accordingly, characterised by changes in the velocity profile power law exponent, 1/n. Considering the significant temporal variation in a tidal channel, the choice of the exponent denominator, n = 6 and n = 9, effectively provides an achievable range around the much-cited value of n = 7 observed at many tidal sites. The resulting flow profiles, which we intend to use in future turbine tests, have been characterised in detail. The results indicate non-uniform vertical shear across the survey area and reveal substantial corner flows, arising from the differential shear between the target vertical and cross-stream shear profiles throughout the measurement domain. In vertically sheared flow, the rotor-equivalent turbulence intensity ranges between 3.0-3.8% throughout the measurement domain for both bar arrangements, while the streamwise integral length scale grows from a characteristic dimension on the order of the bar width, similar to the flow downstream of a turbulence-generating grid. The experimental tests are well-defined and repeatable and serve as a reference for other researchers who wish to undertake similar investigations. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=acoustic%20doppler%20Velocimeter" title="acoustic doppler Velocimeter">acoustic doppler Velocimeter</a>, <a href="https://publications.waset.org/abstracts/search?q=experimental%20hydrodynamics" title=" experimental hydrodynamics"> experimental hydrodynamics</a>, <a href="https://publications.waset.org/abstracts/search?q=open-channel%20flow" title=" open-channel flow"> open-channel flow</a>, <a href="https://publications.waset.org/abstracts/search?q=shear%20profiles" title=" shear profiles"> shear profiles</a>, <a href="https://publications.waset.org/abstracts/search?q=tidal%20stream%20turbines" title=" tidal stream turbines"> tidal stream turbines</a> </p> <a href="https://publications.waset.org/abstracts/178015/hydrodynamic-characterisation-of-a-hydraulic-flume-with-sheared-flow" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/178015.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">86</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">928</span> Comparative Study of Bending Angle in Laser Forming Process Using Artificial Neural Network and Fuzzy Logic System</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=M.%20Hassani">M. Hassani</a>, <a href="https://publications.waset.org/abstracts/search?q=Y.%20Hassani"> Y. Hassani</a>, <a href="https://publications.waset.org/abstracts/search?q=N.%20Ajudanioskooei"> N. Ajudanioskooei</a>, <a href="https://publications.waset.org/abstracts/search?q=N.%20N.%20Benvid"> N. N. Benvid</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Laser Forming process as a non-contact thermal forming process is widely used to forming and bending of metallic and non-metallic sheets. In this process, according to laser irradiation along a specific path, sheet is bent. One of the most important output parameters in laser forming is bending angle that depends on process parameters such as physical and mechanical properties of materials, laser power, laser travel speed and the number of scan passes. In this paper, Artificial Neural Network and Fuzzy Logic System were used to predict of bending angle in laser forming process. Inputs to these models were laser travel speed and laser power. The comparison between artificial neural network and fuzzy logic models with experimental results has been shown both of these models have high ability to prediction of bending angles with minimum errors. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=artificial%20neural%20network" title="artificial neural network">artificial neural network</a>, <a href="https://publications.waset.org/abstracts/search?q=bending%20angle" title=" bending angle"> bending angle</a>, <a href="https://publications.waset.org/abstracts/search?q=fuzzy%20logic" title=" fuzzy logic"> fuzzy logic</a>, <a href="https://publications.waset.org/abstracts/search?q=laser%20forming" title=" laser forming"> laser forming</a> </p> <a href="https://publications.waset.org/abstracts/34045/comparative-study-of-bending-angle-in-laser-forming-process-using-artificial-neural-network-and-fuzzy-logic-system" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/34045.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">597</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">927</span> Optimum Er: YAG Laser Parameters for Orthodontic Composite Debonding: An in vitro Study</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Mohammad%20Zamzam">Mohammad Zamzam</a>, <a href="https://publications.waset.org/abstracts/search?q=Wesam%20Bachir"> Wesam Bachir</a>, <a href="https://publications.waset.org/abstracts/search?q=Imad%20Asaad"> Imad Asaad </a> </p> <p class="card-text"><strong>Abstract:</strong></p> Several studies have produced estimates of Er:YAG laser parameters and specifications but there is still insufficient data for reliable selection of laser parameters. As a consequence, there is a heightened need for ideal specifications of Er:YAG laser to reduce the amount of enamel ablation. The objective of this paper is to investigate the influence of Er:YAG laser parameters, energy level and pulse duration, on orthodontic composite removal after bracket debonding. The sample consisted of 45 cuboids of orthodontic composite made by plastic moulds. The samples were divided into three groups, each was irradiated with Er:YAG laser set at different energy levels and three values for pulse durations (50 µs, 100 µs, and 300 µs). Geometrical parameters (depth and area) of cavities formed by laser irradiation were determined. ANCOVA test showed statistically significant difference (p < 0.0.5) between the groups indicating a potential effect of laser pulse duration on the geometrical parameters after controlling laser energy level. A post-hoc Bonferroni test ranked the 50µ Er:YAG laser pulse as the most influential factor for all geometrical parameters in removing remnant composite from enamel surface. Also, 300 mJ laser pulses caused the largest removal of the composite. The results of the present study demonstrated the efficacy of 50 µs and 300 mJ Er:YAG laser pulse for removal of remnant orthodontic composite. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=enamel" title="enamel">enamel</a>, <a href="https://publications.waset.org/abstracts/search?q=Er%3AYAG" title=" Er:YAG"> Er:YAG</a>, <a href="https://publications.waset.org/abstracts/search?q=geometrical%20parameters" title=" geometrical parameters"> geometrical parameters</a>, <a href="https://publications.waset.org/abstracts/search?q=orthodontic%20composite" title=" orthodontic composite"> orthodontic composite</a>, <a href="https://publications.waset.org/abstracts/search?q=remnant%20composite" title=" remnant composite"> remnant composite</a> </p> <a href="https://publications.waset.org/abstracts/6666/optimum-er-yag-laser-parameters-for-orthodontic-composite-debonding-an-in-vitro-study" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/6666.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">553</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">926</span> To Study the Effect of Optic Fibre Laser Cladding of Cast Iron with Silicon Carbide on Wear Rate</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Kshitij%20Sawke">Kshitij Sawke</a>, <a href="https://publications.waset.org/abstracts/search?q=Pradnyavant%20Kamble"> Pradnyavant Kamble</a>, <a href="https://publications.waset.org/abstracts/search?q=Shrikant%20Patil"> Shrikant Patil</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The study investigates the effect on wear rate of laser clad of cast iron with silicon carbide. Metal components fail their desired use because they wear, which causes them to lose their functionality. The laser has been used as a heating source to create a melt pool over the surface of cast iron, and then a layer of hard silicon carbide is deposited. Various combinations of power and feed rate of laser have experimented. A suitable range of laser processing parameters was identified. Wear resistance and wear rate properties were evaluated and the result showed that the wear resistance of the laser treated samples was exceptional to that of the untreated samples. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=laser%20clad" title="laser clad">laser clad</a>, <a href="https://publications.waset.org/abstracts/search?q=processing%20parameters" title=" processing parameters"> processing parameters</a>, <a href="https://publications.waset.org/abstracts/search?q=wear%20rate" title=" wear rate"> wear rate</a>, <a href="https://publications.waset.org/abstracts/search?q=wear%20resistance" title=" wear resistance"> wear resistance</a> </p> <a href="https://publications.waset.org/abstracts/76458/to-study-the-effect-of-optic-fibre-laser-cladding-of-cast-iron-with-silicon-carbide-on-wear-rate" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/76458.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">257</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">925</span> Effect of Laser Input Energy on the Laser Joining of Polyethylene Terephthalate to Titanium</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Y.%20J.%20Chen">Y. J. Chen</a>, <a href="https://publications.waset.org/abstracts/search?q=T.%20M.%20Yue"> T. M. Yue</a>, <a href="https://publications.waset.org/abstracts/search?q=Z.%20N.%20Guo"> Z. N. Guo</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper reports the effects of laser energy on the characteristics of bubbles generated in the weld zone and the formation of new chemical bonds at the Polyethylene Terephthalate (PET)/Ti joint interface in laser joining of PET to Ti. The samples were produced by using different laser energies ranging from 1.5 J – 6 J in steps of 1.5 J, while all other joining parameters remained unchanged. The types of chemical bonding at the joint interface were analysed by the x-ray photoelectron spectroscopy (XPS) depth-profiling method. The results show that the characteristics of the bubbles and the thickness of the chemically bonded interface, which contains the laser generated bonds of Ti–C and Ti–O, increase markedly with increasing laser energy input. The tensile failure load of the joint depends on the combined effect of the amount and distribution of the bubbles formed and the chemical bonding intensity of the joint interface. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=laser%20direct%20joining" title="laser direct joining">laser direct joining</a>, <a href="https://publications.waset.org/abstracts/search?q=Ti%2FPET%20interface" title=" Ti/PET interface"> Ti/PET interface</a>, <a href="https://publications.waset.org/abstracts/search?q=laser%20energy" title=" laser energy"> laser energy</a>, <a href="https://publications.waset.org/abstracts/search?q=XPS%20depth%20profiling" title=" XPS depth profiling"> XPS depth profiling</a>, <a href="https://publications.waset.org/abstracts/search?q=chemical%20bond" title=" chemical bond"> chemical bond</a>, <a href="https://publications.waset.org/abstracts/search?q=tensile%20failure%20load" title=" tensile failure load"> tensile failure load</a> </p> <a href="https://publications.waset.org/abstracts/52818/effect-of-laser-input-energy-on-the-laser-joining-of-polyethylene-terephthalate-to-titanium" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/52818.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">211</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">924</span> Laser Irradiated GeSn Photodetector for Improved Infrared Photodetection</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Patrik%20Scajev">Patrik Scajev</a>, <a href="https://publications.waset.org/abstracts/search?q=Pavels%20Onufrijevs"> Pavels Onufrijevs</a>, <a href="https://publications.waset.org/abstracts/search?q=Algirdas%20Mekys"> Algirdas Mekys</a>, <a href="https://publications.waset.org/abstracts/search?q=Tadas%20Malinauskas"> Tadas Malinauskas</a>, <a href="https://publications.waset.org/abstracts/search?q=Dominykas%20Augulis"> Dominykas Augulis</a>, <a href="https://publications.waset.org/abstracts/search?q=Liudvikas%20Subacius"> Liudvikas Subacius</a>, <a href="https://publications.waset.org/abstracts/search?q=Kuo-Chih%20Lee"> Kuo-Chih Lee</a>, <a href="https://publications.waset.org/abstracts/search?q=Jevgenijs%20Kaupuzs"> Jevgenijs Kaupuzs</a>, <a href="https://publications.waset.org/abstracts/search?q=Arturs%20Medvids"> Arturs Medvids</a>, <a href="https://publications.waset.org/abstracts/search?q=Hung%20Hsiang%20Cheng"> Hung Hsiang Cheng </a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this study, we focused on the optoelectronic properties of the photodiodes prepared by using 200 nm thick Ge₀.₉₅Sn₀.₀₅ epitaxial layers on Ge/n-Si substrate with aluminum contacts. Photodiodes were formed on non-irradiated and Nd: YAG laser irradiated Ge₀.₉₅Sn₀.₀₅ layers. The samples were irradiated by pulsed Nd: YAG laser with 136.7-462.6 MW/cm² intensity. The photodiodes were characterized by using short laser pulses with the wavelength in the 2.0-2.6 μm range. The laser-irradiated diode was found more sensitive in the long-wavelength range due to laser-induced Sn atoms redistribution providing formation of graded bandgap structure. Sub-millisecond photocurrent relaxation in the diodes revealed their suitability for image sensors. Our findings open the perspective for improving the photo-sensitivity of GeSn alloys in the mid-infrared by pulsed laser processing. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=GeSn" title="GeSn">GeSn</a>, <a href="https://publications.waset.org/abstracts/search?q=laser%20processing" title=" laser processing"> laser processing</a>, <a href="https://publications.waset.org/abstracts/search?q=photodetector" title=" photodetector"> photodetector</a>, <a href="https://publications.waset.org/abstracts/search?q=infrared" title=" infrared"> infrared</a> </p> <a href="https://publications.waset.org/abstracts/131848/laser-irradiated-gesn-photodetector-for-improved-infrared-photodetection" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/131848.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">153</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">923</span> Self-Action Effects of a Non-Gaussian Laser Beam Through Plasma </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Sandeep%20Kumar">Sandeep Kumar</a>, <a href="https://publications.waset.org/abstracts/search?q=Naveen%20Gupta"> Naveen Gupta</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The propagation of the Non-Gaussian laser beam results in strong self-focusing as compare to the Gaussian laser beam, which helps to achieve a prerequisite of the plasma-based electron, Terahertz generation, and higher harmonic generations. The theoretical investigation on the evolution of non-Gaussian laser beam through the collisional plasma with ramped density has been presented. The non-uniform irradiance over the cross-section of the laser beam results in redistribution of the carriers that modifies the optical response of the plasma in such a way that the plasma behaves like a converging lens to the laser beam. The formulation is based on finding a semi-analytical solution of the nonlinear Schrodinger wave equation (NLSE) with the help of variational theory. It has been observed that the decentred parameter ‘q’ of laser and wavenumber of ripples of medium contribute to providing the required conditions for the improvement of self-focusing. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=non-Gaussian%20beam" title="non-Gaussian beam">non-Gaussian beam</a>, <a href="https://publications.waset.org/abstracts/search?q=collisional%20plasma" title=" collisional plasma"> collisional plasma</a>, <a href="https://publications.waset.org/abstracts/search?q=variational%20theory" title=" variational theory"> variational theory</a>, <a href="https://publications.waset.org/abstracts/search?q=self-focusing" title=" self-focusing"> self-focusing</a> </p> <a href="https://publications.waset.org/abstracts/124754/self-action-effects-of-a-non-gaussian-laser-beam-through-plasma" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/124754.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">195</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=laser%20doppler%20velocimeter&page=2">2</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20velocimeter&page=3">3</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20velocimeter&page=4">4</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20velocimeter&page=5">5</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20velocimeter&page=6">6</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20velocimeter&page=7">7</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20velocimeter&page=8">8</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20velocimeter&page=9">9</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20velocimeter&page=10">10</a></li> <li class="page-item disabled"><span class="page-link">...</span></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20velocimeter&page=31">31</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20velocimeter&page=32">32</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=laser%20doppler%20velocimeter&page=2" rel="next">&rsaquo;</a></li> </ul> </div> </main> <footer> <div id="infolinks" class="pt-3 pb-2"> <div class="container"> <div style="background-color:#f5f5f5;" class="p-3"> <div class="row"> <div class="col-md-2"> <ul class="list-unstyled"> About <li><a href="https://waset.org/page/support">About Us</a></li> <li><a href="https://waset.org/page/support#legal-information">Legal</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/WASET-16th-foundational-anniversary.pdf">WASET celebrates its 16th foundational anniversary</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Account <li><a href="https://waset.org/profile">My Account</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Explore <li><a href="https://waset.org/disciplines">Disciplines</a></li> <li><a href="https://waset.org/conferences">Conferences</a></li> <li><a href="https://waset.org/conference-programs">Conference Program</a></li> <li><a href="https://waset.org/committees">Committees</a></li> <li><a href="https://publications.waset.org">Publications</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Research <li><a href="https://publications.waset.org/abstracts">Abstracts</a></li> <li><a href="https://publications.waset.org">Periodicals</a></li> <li><a href="https://publications.waset.org/archive">Archive</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Open Science <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Open-Science-Philosophy.pdf">Open Science Philosophy</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Open-Science-Award.pdf">Open Science Award</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Open-Society-Open-Science-and-Open-Innovation.pdf">Open Innovation</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Postdoctoral-Fellowship-Award.pdf">Postdoctoral Fellowship Award</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Scholarly-Research-Review.pdf">Scholarly Research Review</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Support <li><a href="https://waset.org/page/support">Support</a></li> <li><a href="https://waset.org/profile/messages/create">Contact Us</a></li> <li><a href="https://waset.org/profile/messages/create">Report Abuse</a></li> </ul> </div> </div> </div> </div> </div> <div class="container text-center"> <hr style="margin-top:0;margin-bottom:.3rem;"> <a href="https://creativecommons.org/licenses/by/4.0/" target="_blank" class="text-muted small">Creative Commons Attribution 4.0 International License</a> <div id="copy" class="mt-2">© 2024 World Academy of Science, Engineering and Technology</div> </div> </footer> <a href="javascript:" id="return-to-top"><i class="fas fa-arrow-up"></i></a> <div class="modal" id="modal-template"> <div class="modal-dialog"> <div class="modal-content"> <div class="row m-0 mt-1"> <div class="col-md-12"> <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">×</span></button> </div> </div> <div class="modal-body"></div> </div> </div> </div> <script src="https://cdn.waset.org/static/plugins/jquery-3.3.1.min.js"></script> <script src="https://cdn.waset.org/static/plugins/bootstrap-4.2.1/js/bootstrap.bundle.min.js"></script> <script src="https://cdn.waset.org/static/js/site.js?v=150220211556"></script> <script> jQuery(document).ready(function() { /*jQuery.get("https://publications.waset.org/xhr/user-menu", function (response) { jQuery('#mainNavMenu').append(response); });*/ jQuery.get({ url: "https://publications.waset.org/xhr/user-menu", cache: false }).then(function(response){ jQuery('#mainNavMenu').append(response); }); }); </script> </body> </html>