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distribution</title> <meta name="description" content="Search results for: Rayleigh distribution"> <meta name="keywords" content="Rayleigh distribution"> <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 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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="Rayleigh distribution"> <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> 5213</div> </div> </div> </div> <h1 class="mt-3 mb-3 text-center" style="font-size:1.6rem;">Search results for: Rayleigh distribution</h1> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">5213</span> A New Distribution and Application on the Lifetime Data</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Gamze%20Ozel">Gamze Ozel</a>, <a href="https://publications.waset.org/abstracts/search?q=Selen%20Cakmakyapan"> Selen Cakmakyapan</a> </p> <p class="card-text"><strong>Abstract:</strong></p> We introduce a new model called the Marshall-Olkin Rayleigh distribution which extends the Rayleigh distribution using Marshall-Olkin transformation and has increasing and decreasing shapes for the hazard rate function. Various structural properties of the new distribution are derived including explicit expressions for the moments, generating and quantile function, some entropy measures, and order statistics are presented. The model parameters are estimated by the method of maximum likelihood and the observed information matrix is determined. The potentiality of the new model is illustrated by means of real life data set. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Marshall-Olkin%20distribution" title="Marshall-Olkin distribution">Marshall-Olkin distribution</a>, <a href="https://publications.waset.org/abstracts/search?q=Rayleigh%20distribution" title=" Rayleigh distribution"> Rayleigh distribution</a>, <a href="https://publications.waset.org/abstracts/search?q=estimation" title=" estimation"> estimation</a>, <a href="https://publications.waset.org/abstracts/search?q=maximum%20likelihood" title=" maximum likelihood "> maximum likelihood </a> </p> <a href="https://publications.waset.org/abstracts/30546/a-new-distribution-and-application-on-the-lifetime-data" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/30546.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">501</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">5212</span> Mixed Convective Heat Transfer in Water-Based Al2O3 Nanofluid in Horizontal Rectangular Duct</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Nur%20Irmawati">Nur Irmawati</a>, <a href="https://publications.waset.org/abstracts/search?q=H.%20A.%20Mohammed"> H. A. Mohammed</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In the present study, mixed convection in a horizontal rectangular duct using Al2O3 is numerically investigated. The effects of different Rayleigh number, Reynolds number and radiation on flow and heat transfer characteristics were studied in detail. This study covers Rayleigh number in the range of 2×106≤Ra≤2×107 and Reynolds number in the range of 100≤Re≤1100. Results reveal that the Nusselt number increases as Reynolds and Rayleigh numbers increase. It was also found that the dimensionless temperature distribution increases as Rayleigh number increases. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=numerical%20simulation" title="numerical simulation">numerical simulation</a>, <a href="https://publications.waset.org/abstracts/search?q=mixed%20convection" title=" mixed convection"> mixed convection</a>, <a href="https://publications.waset.org/abstracts/search?q=horizontal%20rectangular%20duct" title=" horizontal rectangular duct"> horizontal rectangular duct</a>, <a href="https://publications.waset.org/abstracts/search?q=nanofluids" title=" nanofluids"> nanofluids</a> </p> <a href="https://publications.waset.org/abstracts/17914/mixed-convective-heat-transfer-in-water-based-al2o3-nanofluid-in-horizontal-rectangular-duct" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/17914.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">376</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">5211</span> Exponentiated Transmuted Weibull Distribution: A Generalization of the Weibull Probability Distribution</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Abd%20El%20Hady%20N.%20Ebraheim">Abd El Hady N. Ebraheim</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper introduces a new generalization of the two parameter Weibull distribution. To this end, the quadratic rank transmutation map has been used. This new distribution is named exponentiated transmuted Weibull (ETW) distribution. The ETW distribution has the advantage of being capable of modeling various shapes of aging and failure criteria. Furthermore, eleven lifetime distributions such as the Weibull, exponentiated Weibull, Rayleigh and exponential distributions, among others follow as special cases. The properties of the new model are discussed and the maximum likelihood estimation is used to estimate the parameters. Explicit expressions are derived for the quantiles. The moments of the distribution are derived, and the order statistics are examined. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=exponentiated" title="exponentiated">exponentiated</a>, <a href="https://publications.waset.org/abstracts/search?q=inversion%20method" title=" inversion method"> inversion method</a>, <a href="https://publications.waset.org/abstracts/search?q=maximum%20likelihood%20estimation" title=" maximum likelihood estimation"> maximum likelihood estimation</a>, <a href="https://publications.waset.org/abstracts/search?q=transmutation%20map" title=" transmutation map"> transmutation map</a> </p> <a href="https://publications.waset.org/abstracts/3470/exponentiated-transmuted-weibull-distribution-a-generalization-of-the-weibull-probability-distribution" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/3470.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">565</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">5210</span> Selection of Rayleigh Damping Coefficients for Seismic Response Analysis of Soil Layers</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Huai-Feng%20Wang">Huai-Feng Wang</a>, <a href="https://publications.waset.org/abstracts/search?q=Meng-Lin%20Lou"> Meng-Lin Lou</a>, <a href="https://publications.waset.org/abstracts/search?q=Ru-Lin%20Zhang"> Ru-Lin Zhang</a> </p> <p class="card-text"><strong>Abstract:</strong></p> One good analysis method in seismic response analysis is direct time integration, which widely adopts Rayleigh damping. An approach is presented for selection of Rayleigh damping coefficients to be used in seismic analyses to produce a response that is consistent with Modal damping response. In the presented approach, the expression of the error of peak response, acquired through complete quadratic combination method, and Rayleigh damping coefficients was set up and then the coefficients were produced by minimizing the error. Two finite element modes of soil layers, excited by 28 seismic waves, were used to demonstrate the feasibility and validity. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Rayleigh%20damping" title="Rayleigh damping">Rayleigh damping</a>, <a href="https://publications.waset.org/abstracts/search?q=modal%20damping" title=" modal damping"> modal damping</a>, <a href="https://publications.waset.org/abstracts/search?q=damping%20coefficients" title=" damping coefficients"> damping coefficients</a>, <a href="https://publications.waset.org/abstracts/search?q=seismic%20response%20analysis" title=" seismic response analysis"> seismic response analysis</a> </p> <a href="https://publications.waset.org/abstracts/57421/selection-of-rayleigh-damping-coefficients-for-seismic-response-analysis-of-soil-layers" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/57421.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">438</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">5209</span> Influence of Rotation on Rayleigh-Type Wave in Piezoelectric Plate</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Soniya%20Chaudhary">Soniya Chaudhary</a>, <a href="https://publications.waset.org/abstracts/search?q=Sanjeev%20Sahu"> Sanjeev Sahu</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Propagation of Rayleigh-type waves in a rotating piezoelectric plate is investigated. The materials are assumed to be transversely isotropic crystals. The frequency equation have been derived for electrically open and short cases. Effect of rotation and piezoelectricity have been shown. It is also found that piezoelectric material properties have an important effect on Rayleigh wave propagation. The result is relevant to the analysis and design of various acoustic surface wave devices constructed from piezoelectric materials also in SAW devices. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=rotation" title="rotation">rotation</a>, <a href="https://publications.waset.org/abstracts/search?q=frequency%20equation" title=" frequency equation"> frequency equation</a>, <a href="https://publications.waset.org/abstracts/search?q=piezoelectricity" title=" piezoelectricity"> piezoelectricity</a>, <a href="https://publications.waset.org/abstracts/search?q=rayleigh-type%20wave" title=" rayleigh-type wave"> rayleigh-type wave</a> </p> <a href="https://publications.waset.org/abstracts/60606/influence-of-rotation-on-rayleigh-type-wave-in-piezoelectric-plate" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/60606.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">313</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">5208</span> Condition Monitoring of Railway Earthworks using Distributed Rayleigh Sensing</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Andrew%20Hall">Andrew Hall</a>, <a href="https://publications.waset.org/abstracts/search?q=Paul%20Clarkson"> Paul Clarkson</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Climate change is predicted to increase the number of extreme weather events intensifying the strain on Railway Earthworks. This paper describes the use of Distributed Rayleigh Sensing to monitor low frequency activity on a vulnerable earthworks sectionprone to landslides alongside a railway line in Northern Spain. The vulnerable slope is instrumented with conventional slope stability sensors allowing an assessment to be conducted of the application of Distributed Rayleigh Sensing as an earthwork condition monitoring tool to enhance the resilience of railway networks. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=condition%20monitoring" title="condition monitoring">condition monitoring</a>, <a href="https://publications.waset.org/abstracts/search?q=railway%20earthworks" title=" railway earthworks"> railway earthworks</a>, <a href="https://publications.waset.org/abstracts/search?q=distributed%20rayleigh%20sensing" title=" distributed rayleigh sensing"> distributed rayleigh sensing</a>, <a href="https://publications.waset.org/abstracts/search?q=climate%20change" title=" climate change"> climate change</a> </p> <a href="https://publications.waset.org/abstracts/141052/condition-monitoring-of-railway-earthworks-using-distributed-rayleigh-sensing" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/141052.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">206</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">5207</span> OFDM Radar for Detecting a Rayleigh Fluctuating Target in Gaussian Noise</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Mahboobeh%20Eghtesad">Mahboobeh Eghtesad</a>, <a href="https://publications.waset.org/abstracts/search?q=Reza%20Mohseni"> Reza Mohseni</a> </p> <p class="card-text"><strong>Abstract:</strong></p> We develop methods for detecting a target for orthogonal frequency division multiplexing (OFDM) based radars. As a preliminary step we introduce the target and Gaussian noise models in discrete–time form. Then, resorting to match filter (MF) we derive a detector for two different scenarios: a non-fluctuating target and a Rayleigh fluctuating target. It will be shown that a MF is not suitable for Rayleigh fluctuating targets. In this paper we propose a reduced-complexity method based on fast Fourier transfrom (FFT) for such a situation. The proposed method has better detection performance. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=constant%20false%20alarm%20rate%20%28CFAR%29" title="constant false alarm rate (CFAR)">constant false alarm rate (CFAR)</a>, <a href="https://publications.waset.org/abstracts/search?q=match%20filter%20%28MF%29" title=" match filter (MF)"> match filter (MF)</a>, <a href="https://publications.waset.org/abstracts/search?q=fast%20Fourier%20transform%20%28FFT%29" title=" fast Fourier transform (FFT)"> fast Fourier transform (FFT)</a>, <a href="https://publications.waset.org/abstracts/search?q=OFDM%20radars" title=" OFDM radars"> OFDM radars</a>, <a href="https://publications.waset.org/abstracts/search?q=Rayleigh%20fluctuating%20target" title=" Rayleigh fluctuating target"> Rayleigh fluctuating target</a> </p> <a href="https://publications.waset.org/abstracts/5922/ofdm-radar-for-detecting-a-rayleigh-fluctuating-target-in-gaussian-noise" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/5922.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">358</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">5206</span> Performance Comparison of Space-Time Block and Trellis Codes under Rayleigh Channels</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Jing%20Qingfeng">Jing Qingfeng</a>, <a href="https://publications.waset.org/abstracts/search?q=Wu%20Jiajia"> Wu Jiajia</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Due to the crowded orbits and shortage of frequency resources, utilizing of MIMO technology to improve spectrum efficiency and increase the capacity has become a necessary trend of broadband satellite communication. We analyze the main influenced factors and compare the BER performance of space-time block code (STBC) scheme and space-time trellis code (STTC) scheme. This paper emphatically studies the bit error rate (BER) performance of STTC and STBC under Rayleigh channel. The main emphasis is placed on the effects of the factors, such as terminal environment and elevation angles, on the BER performance of STBC and STTC schemes. Simulation results indicate that performance of STTC under Rayleigh channel is obviously improved with the increasing of transmitting and receiving antennas numbers, but the encoder state has little impact on the performance. Under Rayleigh channel, performance of Alamouti code is better than that of STTC. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=MIMO" title="MIMO">MIMO</a>, <a href="https://publications.waset.org/abstracts/search?q=space%20time%20block%20code%20%28STBC%29" title=" space time block code (STBC)"> space time block code (STBC)</a>, <a href="https://publications.waset.org/abstracts/search?q=space%20time%20trellis%20code%20%28STTC%29" title=" space time trellis code (STTC)"> space time trellis code (STTC)</a>, <a href="https://publications.waset.org/abstracts/search?q=Rayleigh%20channel" title=" Rayleigh channel"> Rayleigh channel</a> </p> <a href="https://publications.waset.org/abstracts/45895/performance-comparison-of-space-time-block-and-trellis-codes-under-rayleigh-channels" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/45895.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">349</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">5205</span> Measurement of Rayleigh Scattering Cross-Section of ₆₀Nd K X-Rays Elements with 26 ≤ Z≤ 90</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Govind%20Sharma">Govind Sharma</a>, <a href="https://publications.waset.org/abstracts/search?q=Harpreet%20S.%20Kainth"> Harpreet S. Kainth</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Rayleigh scattering differential cross sections have been measured for the 36.84 keV (60Nd Kα2), 37.36 keV (60Nd Kα1) and 42.27 keV (60Nd Kβ1,3) X-rays. These measurements have been done in 44 elements with 22 ≤ Z ≤ 90 at an angle of 1390. The measurements are performed by using a radiation source consisting of an annular 60Nd foil excited by the 59.54 KeV γ-ray photons from 241Am radioactive source. The Nd Kα2, Kβ1,3 X-ray photons from the 60Nd annular foil (secondary photon source) are made to scatter from the target and the scattered photons are detected using Canberra made low energy Germanium (LEGe) detector. The measured Rayleigh scattering cross sections are compared with the theoretical MF, MFASF and the SM values. The noticeable deviations are observed from the MF, MFASF and SM values for 36.84 keV (60Nd Kα2), 37.36 keV (60Nd Kα1) and 42.27 keV (60Nd Kβ1,3) X-rays. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Photon-electron%20interaction" title="Photon-electron interaction">Photon-electron interaction</a>, <a href="https://publications.waset.org/abstracts/search?q=Rayleigh%20scattering" title=" Rayleigh scattering"> Rayleigh scattering</a>, <a href="https://publications.waset.org/abstracts/search?q=X-ray%20fluorescence" title=" X-ray fluorescence"> X-ray fluorescence</a>, <a href="https://publications.waset.org/abstracts/search?q=X-ray" title=" X-ray "> X-ray </a> </p> <a href="https://publications.waset.org/abstracts/79355/measurement-of-rayleigh-scattering-cross-section-of-60nd-k-x-rays-elements-with-26-z-90" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/79355.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">387</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">5204</span> Maximum Likelihood Estimation Methods on a Two-Parameter Rayleigh Distribution under Progressive Type-Ii Censoring</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Daniel%20Fundi%20Murithi">Daniel Fundi Murithi</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Data from economic, social, clinical, and industrial studies are in some way incomplete or incorrect due to censoring. Such data may have adverse effects if used in the estimation problem. We propose the use of Maximum Likelihood Estimation (MLE) under a progressive type-II censoring scheme to remedy this problem. In particular, maximum likelihood estimates (MLEs) for the location (µ) and scale (λ) parameters of two Parameter Rayleigh distribution are realized under a progressive type-II censoring scheme using the Expectation-Maximization (EM) and the Newton-Raphson (NR) algorithms. These algorithms are used comparatively because they iteratively produce satisfactory results in the estimation problem. The progressively type-II censoring scheme is used because it allows the removal of test units before the termination of the experiment. Approximate asymptotic variances and confidence intervals for the location and scale parameters are derived/constructed. The efficiency of EM and the NR algorithms is compared given root mean squared error (RMSE), bias, and the coverage rate. The simulation study showed that in most sets of simulation cases, the estimates obtained using the Expectation-maximization algorithm had small biases, small variances, narrower/small confidence intervals width, and small root of mean squared error compared to those generated via the Newton-Raphson (NR) algorithm. Further, the analysis of a real-life data set (data from simple experimental trials) showed that the Expectation-Maximization (EM) algorithm performs better compared to Newton-Raphson (NR) algorithm in all simulation cases under the progressive type-II censoring scheme. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=expectation-maximization%20algorithm" title="expectation-maximization algorithm">expectation-maximization algorithm</a>, <a href="https://publications.waset.org/abstracts/search?q=maximum%20likelihood%20estimation" title=" maximum likelihood estimation"> maximum likelihood estimation</a>, <a href="https://publications.waset.org/abstracts/search?q=Newton-Raphson%20method" title=" Newton-Raphson method"> Newton-Raphson method</a>, <a href="https://publications.waset.org/abstracts/search?q=two-parameter%20Rayleigh%20distribution" title=" two-parameter Rayleigh distribution"> two-parameter Rayleigh distribution</a>, <a href="https://publications.waset.org/abstracts/search?q=progressive%20type-II%20censoring" title=" progressive type-II censoring"> progressive type-II censoring</a> </p> <a href="https://publications.waset.org/abstracts/122112/maximum-likelihood-estimation-methods-on-a-two-parameter-rayleigh-distribution-under-progressive-type-ii-censoring" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/122112.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">163</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">5203</span> Analysis of Three-Dimensional Longitudinal Rolls Induced by Double Diffusive Poiseuille-Rayleigh-Benard Flows in Rectangular Channels</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=O.%20Rahli">O. Rahli</a>, <a href="https://publications.waset.org/abstracts/search?q=N.%20Mimouni"> N. Mimouni</a>, <a href="https://publications.waset.org/abstracts/search?q=R.%20Bennacer"> R. Bennacer</a>, <a href="https://publications.waset.org/abstracts/search?q=K.%20Bouhadef"> K. Bouhadef</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This numerical study investigates the travelling wave’s appearance and the behavior of Poiseuille-Rayleigh-Benard (PRB) flow induced in 3D thermosolutale mixed convection (TSMC) in horizontal rectangular channels. The governing equations are discretized by using a control volume method with third order Quick scheme in approximating the advection terms. Simpler algorithm is used to handle coupling between the momentum and continuity equations. To avoid the excessively high computer time, full approximation storage (FAS) with full multigrid (FMG) method is used to solve the problem. For a broad range of dimensionless controlling parameters, the contribution of this work is to analyzing the flow regimes of the steady longitudinal thermoconvective rolls (noted R//) for both thermal and mass transfer (TSMC). The transition from the opposed volume forces to cooperating ones, considerably affects the birth and the development of the longitudinal rolls. The heat and mass transfers distribution are also examined. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=heat%20and%20mass%20transfer" title="heat and mass transfer">heat and mass transfer</a>, <a href="https://publications.waset.org/abstracts/search?q=mixed%20convection" title=" mixed convection"> mixed convection</a>, <a href="https://publications.waset.org/abstracts/search?q=poiseuille-rayleigh-benard%20flow" title=" poiseuille-rayleigh-benard flow"> poiseuille-rayleigh-benard flow</a>, <a href="https://publications.waset.org/abstracts/search?q=rectangular%20duct" title=" rectangular duct"> rectangular duct</a> </p> <a href="https://publications.waset.org/abstracts/51259/analysis-of-three-dimensional-longitudinal-rolls-induced-by-double-diffusive-poiseuille-rayleigh-benard-flows-in-rectangular-channels" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/51259.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">298</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">5202</span> Quantification of Effects of Structure-Soil-Structure Interactions on Urban Environment under Rayleigh Wave Loading</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Neeraj%20Kumar">Neeraj Kumar</a>, <a href="https://publications.waset.org/abstracts/search?q=J.%20P.%20Narayan"> J. P. Narayan</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The effects of multiple Structure-Soil-Structure Interactions (SSSI) on the seismic wave-field is generally disregarded by earthquake engineers, particularly the surface waves which cause more damage to buildings. Closely built high rise buildings exchange substantial seismic energy with each other and act as a full-coupled dynamic system. In this paper, SSI effects on the building responses and the free field motion due to a small city consisting 25- homogenous buildings blocks of 10-storey are quantified. The rocking and translational behavior of building under Rayleigh wave loading is studied for different dimensions of the building. The obtained dynamic parameters of buildings revealed a reduction in building roof drift with an increase in number of buildings ahead of the considered building. The strain developed by vertical component of Rayleigh may cause tension in structural components of building. A matching of fundamental frequency of building for the horizontal component of Rayleigh wave with that for vertically incident SV-wave is obtained. Further, the fundamental frequency of building for the vertical vibration is approximately twice to that for horizontal vibration. The city insulation has caused a reduction of amplitude of Rayleigh wave up to 19.3% and 21.6% in the horizontal and vertical components, respectively just outside the city. Further, the insulating effect of city was very large at fundamental frequency of buildings for both the horizontal and vertical components. Therefore, it is recommended to consider the insulating effects of city falling in the path of Rayleigh wave propagation in seismic hazard assessment for an area. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=structure-soil-structure%20interactions" title="structure-soil-structure interactions">structure-soil-structure interactions</a>, <a href="https://publications.waset.org/abstracts/search?q=Rayleigh%20wave%20propagation" title=" Rayleigh wave propagation"> Rayleigh wave propagation</a>, <a href="https://publications.waset.org/abstracts/search?q=finite%20difference%20simulation" title=" finite difference simulation"> finite difference simulation</a>, <a href="https://publications.waset.org/abstracts/search?q=dynamic%20response%20of%20buildings" title=" dynamic response of buildings"> dynamic response of buildings</a> </p> <a href="https://publications.waset.org/abstracts/75186/quantification-of-effects-of-structure-soil-structure-interactions-on-urban-environment-under-rayleigh-wave-loading" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/75186.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">215</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">5201</span> Influence of Initial Stress and Corrugation on Rayleigh-Type Wave in Piezomagnetic Half-Space</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Abhinav%20Singhal">Abhinav Singhal</a>, <a href="https://publications.waset.org/abstracts/search?q=Sanjeev%20A.%20Sahu"> Sanjeev A. Sahu</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Propagation of Rayleigh-type surface waves in an initially stressed piezomagnetic half- space with irregular boundary is investigated. The materials are assumed to be transversely isotropic crystals. The dispersion relations have been derived for electrically open and short cases. Effect of initial stress and corrugation have been shown graphically. It is also found that piezomagnetic material properties have an important effect on wave propagation. The result is relevant to the analysis and design of various acoustic surface wave devices constructed from piezomagnetic materials. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=corrugation" title="corrugation">corrugation</a>, <a href="https://publications.waset.org/abstracts/search?q=frequency%20equation" title=" frequency equation"> frequency equation</a>, <a href="https://publications.waset.org/abstracts/search?q=piezomagnetic" title=" piezomagnetic"> piezomagnetic</a>, <a href="https://publications.waset.org/abstracts/search?q=rayleigh-type%20wave" title=" rayleigh-type wave"> rayleigh-type wave</a> </p> <a href="https://publications.waset.org/abstracts/58182/influence-of-initial-stress-and-corrugation-on-rayleigh-type-wave-in-piezomagnetic-half-space" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/58182.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">266</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">5200</span> Effect of Loose Bonding and Corrugated Boundary Surface on Propagation of Rayleigh-Type Wave</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Kshitish%20Ch.%20Mistri">Kshitish Ch. Mistri</a>, <a href="https://publications.waset.org/abstracts/search?q=Abhishek%20Kumar%20Singh"> Abhishek Kumar Singh</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The effect of undulatory boundary surface of a medium as well as the degree of bonding between two consecutive mediums, on the propagation of surface waves is an unavoidable matter of fact. Therefore, this paper investigates the propagation of Rayleigh-type wave in a corrugated fibre-reinforced layer overlying an initially stressed orthotropic half-space under gravity. Also, the two mediums are assumed to be loosely (or imperfectly) bonded. Numerical computation of the obtained frequency equation has been carried out which aids to analyze the influence of corrugation, loose bonding, initial stress and gravity on the phase velocity of Rayleigh-type wave. Moreover, the presence and absence of corrugation, loose bonding and initial stress are also discussed in a comparative manner. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=corrugated%20boundary%20surface" title="corrugated boundary surface">corrugated boundary surface</a>, <a href="https://publications.waset.org/abstracts/search?q=fibre-reinforced%20layer" title=" fibre-reinforced layer"> fibre-reinforced layer</a>, <a href="https://publications.waset.org/abstracts/search?q=initial%20stress" title=" initial stress"> initial stress</a>, <a href="https://publications.waset.org/abstracts/search?q=loose%20bonding" title=" loose bonding"> loose bonding</a>, <a href="https://publications.waset.org/abstracts/search?q=orthotropic%20half-space" title=" orthotropic half-space"> orthotropic half-space</a>, <a href="https://publications.waset.org/abstracts/search?q=Rayleigh-type%20wave" title=" Rayleigh-type wave"> Rayleigh-type wave</a> </p> <a href="https://publications.waset.org/abstracts/60386/effect-of-loose-bonding-and-corrugated-boundary-surface-on-propagation-of-rayleigh-type-wave" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/60386.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">276</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">5199</span> Structural Element Vibration Analysis with finite element method: Use of Rayleigh Quotient</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Houari%20Boumediene%20University%20of%20Science">Houari Boumediene University of Science</a>, <a href="https://publications.waset.org/abstracts/search?q=Technology.">Technology.</a> </p> <p class="card-text"><strong>Abstract:</strong></p> "Various methods are typically used in the dynamic analysis of transversely vibrating beams. To achieve this, numerical methods are used to solve the general eigenvalue problem. The equations of equilibrium, which describe the motion, are derived from a fourth-order differential equation. Our study is based on the finite element method, and the results of the investigation are the vibration frequencies obtained using the Jacobi method. Two types of elementary mass matrices are considered: one representing a uniform distribution of mass along the element and the other consisting of concentrated masses located at fixed points whose number increases progressively with equal distances at each evaluation stage. The beams studied have different boundary constraints, representing several classical situations. Comparisons are made for beams where the distributed mass is replaced by n concentrated masses. As expected, the first calculation stage involves determining the lowest number of beam parts that gives a frequency comparable to that obtained from the Rayleigh formula. The obtained values are then compared to theoretical results based on the assumptions of the Bernoulli-Euler theory. These steps are repeated for the second type of mass representation in the same manner." <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=finite%20element%20method" title="finite element method">finite element method</a>, <a href="https://publications.waset.org/abstracts/search?q=bernouilli%20eulertheory" title=" bernouilli eulertheory"> bernouilli eulertheory</a>, <a href="https://publications.waset.org/abstracts/search?q=structural%20analysis" title=" structural analysis"> structural analysis</a>, <a href="https://publications.waset.org/abstracts/search?q=vibration%20analysis" title=" vibration analysis"> vibration analysis</a>, <a href="https://publications.waset.org/abstracts/search?q=rayleigh%20quotient" title=" rayleigh quotient"> rayleigh quotient</a> </p> <a href="https://publications.waset.org/abstracts/163627/structural-element-vibration-analysis-with-finite-element-method-use-of-rayleigh-quotient" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/163627.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">92</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">5198</span> Tracking the Effect of Ibutilide on Amplitude and Frequency of Fibrillatory Intracardiac Electrograms Using the Regression Analysis</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=H.%20Hajimolahoseini">H. Hajimolahoseini</a>, <a href="https://publications.waset.org/abstracts/search?q=J.%20Hashemi"> J. Hashemi</a>, <a href="https://publications.waset.org/abstracts/search?q=D.%20Redfearn"> D. Redfearn</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Background: Catheter ablation is an effective therapy for symptomatic atrial fibrillation (AF). The intracardiac electrocardiogram (IEGM) collected during this procedure contains precious information that has not been explored to its full capacity. Novel processing techniques allow looking at these recordings from different perspectives which can lead to improved therapeutic approaches. In our previous study, we showed that variation in amplitude measured through Shannon Entropy could be used as an AF recurrence risk stratification factor in patients who received Ibutilide before the electrograms were recorded. The aim of this study is to further investigate the effect of Ibutilide on characteristics of the recorded signals from the left atrium (LA) of a patient with persistent AF before and after administration of the drug. Methods: The IEGMs collected from different intra-atrial sites of 12 patients were studied and compared before and after Ibutilide administration. First, the before and after Ibutilide IEGMs that were recorded within a Euclidian distance of 3 mm in LA were selected as pairs for comparison. For every selected pair of IEGMs, the Probability Distribution Function (PDF) of the amplitude in time domain and magnitude in frequency domain was estimated using the regression analysis. The PDF represents the relative likelihood of a variable falling within a specific range of values. Results: Our observations showed that in time domain, the PDF of amplitudes was fitted to a Gaussian distribution while in frequency domain, it was fitted to a Rayleigh distribution. Our observations also revealed that after Ibutilide administration, the IEGMs would have significantly narrower short-tailed PDFs both in time and frequency domains. Conclusion: This study shows that the PDFs of the IEGMs before and after administration of Ibutilide represents significantly different properties, both in time and frequency domains. Hence, by fitting the PDF of IEGMs in time domain to a Gaussian distribution or in frequency domain to a Rayleigh distribution, the effect of Ibutilide can easily be tracked using the statistics of their PDF (e.g., standard deviation) while this is difficult through the waveform of IEGMs itself. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=atrial%20fibrillation" title="atrial fibrillation">atrial fibrillation</a>, <a href="https://publications.waset.org/abstracts/search?q=catheter%20ablation" title=" catheter ablation"> catheter ablation</a>, <a href="https://publications.waset.org/abstracts/search?q=probability%20distribution%20function" title=" probability distribution function"> probability distribution function</a>, <a href="https://publications.waset.org/abstracts/search?q=time-frequency%20characteristics" title=" time-frequency characteristics"> time-frequency characteristics</a> </p> <a href="https://publications.waset.org/abstracts/80384/tracking-the-effect-of-ibutilide-on-amplitude-and-frequency-of-fibrillatory-intracardiac-electrograms-using-the-regression-analysis" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/80384.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">5197</span> Effect of Two Radial Fins on Heat Transfer and Flow Structure in a Horizontal Annulus</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Anas%20El%20Amraoui">Anas El Amraoui</a>, <a href="https://publications.waset.org/abstracts/search?q=Abdelkhalek%20Cheddadi"> Abdelkhalek Cheddadi</a>, <a href="https://publications.waset.org/abstracts/search?q=Mohammed%20Touhami%20Ouazzani"> Mohammed Touhami Ouazzani</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Laminar natural convection in a cylindrical annular cavity filled with air and provided with two fins is studied numerically using the discretization of the governing equations with the Centered Finite Difference method based on the Alternating Direction Implicit (ADI) scheme. The fins are attached to the inner cylinder of radius <em>r<sub>i</sub></em> (hot wall of temperature <em>T<sub>i</sub></em>). The outer cylinder of radius <em>r<sub>o</sub></em> is maintained at a temperature <em>T<sub>o</sub></em> (<em>T<sub>o</sub></em> < <em>T<sub>i</sub></em>). Two values of the dimensionless thickness of the fins are considered: 0.015 and 0.203. We consider a low fin height equal to 0.078 and medium fin heights equal to 0.093 and 0.203. The position of the fin is 0.82π and the radius ratio is equal to 2. The effect of Rayleigh number, <em>Ra</em>, on the flow structure and heat transfer is analyzed for a range of <em>Ra</em> from 10<sup>3</sup> to 10<sup>4</sup>. The results for established flow structures and heat transfer at low height indicate that the flow regime that occurs is unicellular for all <em>Ra</em> and fin thickness; in addition, the heat transfer rate increases with increasing Rayleigh number and is the same for both thicknesses. At median fin heights 0.093 and 0.203, the increase of Rayleigh number leads to transitions of flow structure which correspond to significant variations of the heat transfer. The critical Rayleigh numbers, <em>Ra<sub>c.app</sub></em> and <em>Ra<sub>c.disp</sub></em> corresponding to the appearance of the bicellular flow regime and its disappearance, are determined and their influence on the change of heat transfer rate is analyzed. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=natural%20convection" title="natural convection">natural convection</a>, <a href="https://publications.waset.org/abstracts/search?q=fins" title=" fins"> fins</a>, <a href="https://publications.waset.org/abstracts/search?q=critical%20Rayleigh%20number" title=" critical Rayleigh number"> critical Rayleigh number</a>, <a href="https://publications.waset.org/abstracts/search?q=heat%20transfer" title=" heat transfer"> heat transfer</a>, <a href="https://publications.waset.org/abstracts/search?q=fluid%20flow%20regime" title=" fluid flow regime"> fluid flow regime</a>, <a href="https://publications.waset.org/abstracts/search?q=horizontal%20annulus" title=" horizontal annulus"> horizontal annulus</a> </p> <a href="https://publications.waset.org/abstracts/116576/effect-of-two-radial-fins-on-heat-transfer-and-flow-structure-in-a-horizontal-annulus" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/116576.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">403</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">5196</span> Numerical Analysis of Multiplicity and Transition Phenomena in Natural Convection</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Hadi%20Kafil">Hadi Kafil</a>, <a href="https://publications.waset.org/abstracts/search?q=Ali%20Ecder"> Ali Ecder</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Heat transfer by natural convection in two-dimensional and three-dimensional axisymmetric enclosure fitted with partially heated vertical walls is investigated numerically. The range of Rayleigh number is varied from 10³ until convective flow becomes unstable. This research focuses on multiplicity and transition phenomena in natural convection and is based on a parametric analysis to study the onset of bifurcations. It is found that, even at low Rayleigh numbers, the flow undergoes a series of turning-point bifurcations which increase the rate of natural convention. On the other hand, by partially heating or cooling the walls, more effective results can be achieved for both heating and cooling applications, such as cooling of electronic devices and heating processes in solidification and crystal growth. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=natural%20convection" title="natural convection">natural convection</a>, <a href="https://publications.waset.org/abstracts/search?q=partial%20heated" title=" partial heated"> partial heated</a>, <a href="https://publications.waset.org/abstracts/search?q=onset%20of%20bifurcation" title=" onset of bifurcation"> onset of bifurcation</a>, <a href="https://publications.waset.org/abstracts/search?q=Rayleigh%20number" title=" Rayleigh number"> Rayleigh number</a> </p> <a href="https://publications.waset.org/abstracts/11789/numerical-analysis-of-multiplicity-and-transition-phenomena-in-natural-convection" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/11789.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">5195</span> Stationary Energy Partition between Waves in a Carbyne Chain</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Svetlana%20Nikitenkova">Svetlana Nikitenkova</a>, <a href="https://publications.waset.org/abstracts/search?q=Dmitry%20Kovriguine"> Dmitry Kovriguine</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Stationary energy partition between waves in a one dimensional carbyne chain at ambient temperatures is investigated. The study is carried out by standard asymptotic methods of nonlinear dynamics in the framework of classical mechanics, based on a simple mathematical model, taking into account central and noncentral interactions between carbon atoms. Within the first-order nonlinear approximation analysis, triple-mode resonant ensembles of quasi-harmonic waves are revealed. Any resonant triad consists of a single primary high-frequency longitudinal mode and a pair of secondary low-frequency transverse modes of oscillations. In general, the motion of the carbyne chain is described by a superposition of resonant triads of various spectral scales. It is found that the stationary energy distribution is obeyed to the classical Rayleigh–Jeans law, at the expense of the proportional amplitude dispersion, except a shift in the frequency band, upwards the spectrum. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=resonant%20triplet" title="resonant triplet">resonant triplet</a>, <a href="https://publications.waset.org/abstracts/search?q=Rayleigh%E2%80%93Jeans%20law" title=" Rayleigh–Jeans law"> Rayleigh–Jeans law</a>, <a href="https://publications.waset.org/abstracts/search?q=amplitude%20dispersion" title=" amplitude dispersion"> amplitude dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=carbyne" title=" carbyne"> carbyne</a> </p> <a href="https://publications.waset.org/abstracts/35622/stationary-energy-partition-between-waves-in-a-carbyne-chain" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/35622.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">443</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">5194</span> Monitoring the Railways by Means of C-OTDR Technology</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Andrey%20V.%20Timofeev">Andrey V. Timofeev</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper presents development results of the method of seismoacoustic activity monitoring based on usage vibrosensitive properties of optical fibers. Analysis of Rayleigh backscattering radiation parameters changes, which take place due to microscopic seismoacoustic impacts on the optical fiber, allows to determine seismoacoustic emission sources positions and to identify their types. Results of using this approach are successful for complex monitoring of railways. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=C-OTDR%20systems" title="C-OTDR systems">C-OTDR systems</a>, <a href="https://publications.waset.org/abstracts/search?q=monitoring%20of%20railways" title=" monitoring of railways"> monitoring of railways</a>, <a href="https://publications.waset.org/abstracts/search?q=Rayleigh%20backscattering" title=" Rayleigh backscattering"> Rayleigh backscattering</a>, <a href="https://publications.waset.org/abstracts/search?q=eismoacoustic%20activity" title=" eismoacoustic activity"> eismoacoustic activity</a> </p> <a href="https://publications.waset.org/abstracts/19692/monitoring-the-railways-by-means-of-c-otdr-technology" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/19692.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">395</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">5193</span> Rayleigh-Bénard-Taylor Convection of Newtonian Nanoliquid</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=P.%20G.%20Siddheshwar">P. G. Siddheshwar</a>, <a href="https://publications.waset.org/abstracts/search?q=T.%20N.%20Sakshath"> T. N. Sakshath</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In the paper we make linear and non-linear stability analyses of Rayleigh-Bénard convection of a Newtonian nanoliquid in a rotating medium (called as Rayleigh-Bénard-Taylor convection). Rigid-rigid isothermal boundaries are considered for investigation. Khanafer-Vafai-Lightstone single phase model is used for studying instabilities in nanoliquids. Various thermophysical properties of nanoliquid are obtained using phenomenological laws and mixture theory. The eigen boundary value problem is solved for the Rayleigh number using an analytical method by considering trigonometric eigen functions. We observe that the critical nanoliquid Rayleigh number is less than that of the base liquid. Thus the onset of convection is advanced due to the addition of nanoparticles. So, increase in volume fraction leads to advanced onset and thereby increase in heat transport. The amplitudes of convective modes required for estimating the heat transport are determined analytically. The tri-modal standard Lorenz model is derived for the steady state assuming small scale convective motions. The effect of rotation on the onset of convection and on heat transport is investigated and depicted graphically. It is observed that the onset of convection is delayed due to rotation and hence leads to decrease in heat transport. Hence, rotation has a stabilizing effect on the system. This is due to the fact that the energy of the system is used to create the component V. We observe that the amount of heat transport is less in the case of rigid-rigid isothermal boundaries compared to free-free isothermal boundaries. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=nanoliquid" title="nanoliquid">nanoliquid</a>, <a href="https://publications.waset.org/abstracts/search?q=rigid-rigid" title=" rigid-rigid"> rigid-rigid</a>, <a href="https://publications.waset.org/abstracts/search?q=rotation" title=" rotation"> rotation</a>, <a href="https://publications.waset.org/abstracts/search?q=single%20phase" title=" single phase"> single phase</a> </p> <a href="https://publications.waset.org/abstracts/69850/rayleigh-benard-taylor-convection-of-newtonian-nanoliquid" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/69850.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">234</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">5192</span> Rayleigh Wave Propagation in an Orthotropic Medium under the Influence of Exponentially Varying Inhomogeneities </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Sumit%20Kumar%20Vishwakarma">Sumit Kumar Vishwakarma</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The aim of the paper is to investigate the influence of inhomogeneity associated with the elastic constants and density of the orthotropic medium. The inhomogeneity is considered as exponential function of depth. The impact of gravity had been discussed. Using the concept of separation of variables, the system of a partial differential equation (equation of motion) has been converted into ordinary differential equation, which is coupled in nature. It further reduces to a biquadratic equation whose roots were found by using MATLAB. A suitable boundary condition is employed to derive the dispersion equation in a closed-form. Numerical simulations had been performed to show the influence of the inhomogeneity parameter. It was observed that as the numerical values of increases, the phase velocity of Rayleigh waves decreases at a particular wavenumber. Graphical illustrations were drawn to visualize the effect of the increasing and decreasing values of the inhomogeneity parameter. It can be concluded that it has a remarkable bearing on the phase velocity as well as damping velocity. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Rayleigh%20waves" title="Rayleigh waves">Rayleigh waves</a>, <a href="https://publications.waset.org/abstracts/search?q=orthotropic%20medium" title=" orthotropic medium"> orthotropic medium</a>, <a href="https://publications.waset.org/abstracts/search?q=gravity%20field" title=" gravity field"> gravity field</a>, <a href="https://publications.waset.org/abstracts/search?q=inhomogeneity" title=" inhomogeneity"> inhomogeneity</a> </p> <a href="https://publications.waset.org/abstracts/123019/rayleigh-wave-propagation-in-an-orthotropic-medium-under-the-influence-of-exponentially-varying-inhomogeneities" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/123019.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">127</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">5191</span> Three-Dimensional Unsteady Natural Convection and Entropy Generation in an Inclined Cubical Trapezoidal Cavity Subjected to Uniformly Heated Bottom Wall</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Farshid%20Fathinia">Farshid Fathinia</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Numerical computation of unsteady laminar three-dimensional natural convection and entropy generation in an inclined cubical trapezoidal air-filled cavity is performed for the first time in this work. The vertical right and left sidewalls of the cavity are maintained at constant cold temperatures. The lower wall is subjected to a constant hot temperature, while the upper one is considered insulated. Computations are performed for Rayleigh numbers varied as 103 ≤ Ra ≤ 105, while the trapezoidal cavity inclination angle is varied as 0° ≤ ϕ ≤ 180°. Prandtl number is considered constant at Pr = 0.71. The second law of thermodynamics is applied to obtain thermodynamic losses inside the cavity due to both heat transfer and fluid friction irreversibilities. The variation of local and average Nusselt numbers are presented and discussed.While, streamlines, isotherms and entropy contours are presented in both two and three-dimensional pattern. The results show that when the Rayleigh number increases, the flow patterns are changed especially in three-dimensional results and the flow circulation increases. Also, the inclination angle effect on the total entropy generation becomes insignificant when the Rayleigh number is low.Moreover, when the Rayleigh number increases the average Nusselt number increases. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=transient%20natural%20convection" title="transient natural convection">transient natural convection</a>, <a href="https://publications.waset.org/abstracts/search?q=trapezoidal%20cavity" title=" trapezoidal cavity"> trapezoidal cavity</a>, <a href="https://publications.waset.org/abstracts/search?q=three-dimensional%20flow" title=" three-dimensional flow"> three-dimensional flow</a>, <a href="https://publications.waset.org/abstracts/search?q=entropy%20generation" title=" entropy generation"> entropy generation</a>, <a href="https://publications.waset.org/abstracts/search?q=second%20law" title=" second law "> second law </a> </p> <a href="https://publications.waset.org/abstracts/24831/three-dimensional-unsteady-natural-convection-and-entropy-generation-in-an-inclined-cubical-trapezoidal-cavity-subjected-to-uniformly-heated-bottom-wall" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/24831.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">350</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">5190</span> Effect of Corrugating Bottom Surface on Natural Convection in a Square Porous Enclosure </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Khedidja%20Bouhadef">Khedidja Bouhadef</a>, <a href="https://publications.waset.org/abstracts/search?q=Imene%20Said%20Kouadri"> Imene Said Kouadri</a>, <a href="https://publications.waset.org/abstracts/search?q=Omar%20Rahli"> Omar Rahli</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this paper numerical investigation is performed to analyze natural convection heat transfer characteristics within a wavy-wall enclosure filled with fluid-saturated porous medium. The bottom wall which has the wavy geometry is maintained at a constant high temperature, while the top wall is straight and is maintained at a constant lower temperature. The left and right walls of the enclosure are both straight and insulated. The governing differential equations are solved by Finite-volume approach and grid generation is used to transform the physical complex domain to a computational regular space. The aim is to examine flow field, temperature distribution and heat transfer evolutions inside the cavity when Darcy number, Rayleigh number and undulations number values are varied. The results mainly indicate that the heat transfer is rather affected by the permeability and Rayleigh number values since increasing these values enhance the Nusselt number; although the exchanges are not highly affected by the undulations number. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=grid%20generation" title="grid generation">grid generation</a>, <a href="https://publications.waset.org/abstracts/search?q=natural%20convection" title=" natural convection"> natural convection</a>, <a href="https://publications.waset.org/abstracts/search?q=porous%20medium" title=" porous medium"> porous medium</a>, <a href="https://publications.waset.org/abstracts/search?q=wavy%20wall%20enclosure" title=" wavy wall enclosure"> wavy wall enclosure</a> </p> <a href="https://publications.waset.org/abstracts/52016/effect-of-corrugating-bottom-surface-on-natural-convection-in-a-square-porous-enclosure" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/52016.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">264</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">5189</span> BER of the Leaky Feeder under Rayleigh Fading Multichannel Reception with Imperfect Phase Estimation</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Hasan%20Farahneh">Hasan Farahneh</a>, <a href="https://publications.waset.org/abstracts/search?q=Xavier%20Fernando"> Xavier Fernando</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Leaky Feeder (LF) has been a proven technology for many decades and its promises broadband wireless access in short range but being overlooked until now. The LF is a natural MIMO transceiver ideal for micro and pico cells. In this work, the LF is considered as a linear antenna array MultiInput-Single-Output (MISO) and derive the average bit error rate (BER) in Rayleigh fading channel considering ideal and independent paths (iid) which consider there is no correlation and mutual coupling between transmit antennas (slots) or receiver antenna considering QPSK modulation with imperfect phase estimation. We consider maximal ratio transmission (MRT) at the transmit end and maximal ratio combining (MRC) at the receiving end. Analytical expressions are derived for the BER with radiating cable transmitters. The effects of slot spacing and carrier frequency on the BER are also studied. Numerical evaluations show the radiating cable transmitter offer much lower BER than a single antenna transmitter with same SNR. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=leaky%20feeder" title="leaky feeder">leaky feeder</a>, <a href="https://publications.waset.org/abstracts/search?q=BER" title=" BER"> BER</a>, <a href="https://publications.waset.org/abstracts/search?q=QPSK" title=" QPSK"> QPSK</a>, <a href="https://publications.waset.org/abstracts/search?q=rayleigh%20fading" title=" rayleigh fading"> rayleigh fading</a>, <a href="https://publications.waset.org/abstracts/search?q=channel%20gain" title=" channel gain"> channel gain</a>, <a href="https://publications.waset.org/abstracts/search?q=phase%20mismatch" title=" phase mismatch"> phase mismatch</a> </p> <a href="https://publications.waset.org/abstracts/50123/ber-of-the-leaky-feeder-under-rayleigh-fading-multichannel-reception-with-imperfect-phase-estimation" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/50123.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">5188</span> Entropy Generation of Natural Convection Heat Transfer in a Square Cavity Using Al2O3-Water Nanofluid</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=M.%20Alipanah">M. Alipanah</a>, <a href="https://publications.waset.org/abstracts/search?q=A.%20Ranjbar"> A. Ranjbar</a>, <a href="https://publications.waset.org/abstracts/search?q=E.%20Farnad"> E. Farnad</a>, <a href="https://publications.waset.org/abstracts/search?q=F.%20Alipanah"> F. Alipanah</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Entropy generation of an Al2O3-water nanofluid due to heat transfer and fluid friction irreversibility has been investigated in a square cavity subject to different side wall temperatures using a nanofluid for natural convection flow. This study has been carried out for the pertinent parameters in the following ranges: Rayleigh number between 104 to 107 and volume fraction between 0 to 0.05. Based on the obtained dimensionless velocity and temperature values, the distributions of local entropy generation, average entropy generation and average Bejan number are determined. The results are compared for a pure fluid and a nanofluid. It is totally found that the heat transfer and entropy generation of the nanofluid is more than the pure fluid and minimum entropy generation and Nusselt number occur in the pure fluid at any Rayleigh number. Results depict that the addition of nanoparticles to the pure fluid has more effect on the entropy generation as the Rayleigh number goes up. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=entropy%20generation" title="entropy generation">entropy generation</a>, <a href="https://publications.waset.org/abstracts/search?q=natural%20convection" title=" natural convection"> natural convection</a>, <a href="https://publications.waset.org/abstracts/search?q=bejan%20number" title=" bejan number"> bejan number</a>, <a href="https://publications.waset.org/abstracts/search?q=nuselt%20number" title=" nuselt number"> nuselt number</a>, <a href="https://publications.waset.org/abstracts/search?q=nanofluid" title=" nanofluid"> nanofluid</a> </p> <a href="https://publications.waset.org/abstracts/10068/entropy-generation-of-natural-convection-heat-transfer-in-a-square-cavity-using-al2o3-water-nanofluid" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/10068.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">499</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">5187</span> A Study on Method for Identifying Capacity Factor Declination of Wind Turbines</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Dongheon%20Shin">Dongheon Shin</a>, <a href="https://publications.waset.org/abstracts/search?q=Kyungnam%20Ko"> Kyungnam Ko</a>, <a href="https://publications.waset.org/abstracts/search?q=Jongchul%20Huh"> Jongchul Huh</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The investigation on wind turbine degradation was carried out using the nacelle wind data. The three Vestas V80-2MW wind turbines of Sungsan wind farm in Jeju Island, South Korea were selected for this work. The SCADA data of the wind farm for five years were analyzed to draw power curve of the turbines. It is assumed that the wind distribution is the Rayleigh distribution to calculate the normalized capacity factor based on the drawn power curve of the three wind turbines for each year. The result showed that the reduction of power output from the three wind turbines occurred every year and the normalized capacity factor decreased to 0.12%/year on average. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=wind%20energy" title="wind energy">wind energy</a>, <a href="https://publications.waset.org/abstracts/search?q=power%20curve" title=" power curve"> power curve</a>, <a href="https://publications.waset.org/abstracts/search?q=capacity%20factor" title=" capacity factor"> capacity factor</a>, <a href="https://publications.waset.org/abstracts/search?q=annual%20energy%20production" title=" annual energy production"> annual energy production</a> </p> <a href="https://publications.waset.org/abstracts/21424/a-study-on-method-for-identifying-capacity-factor-declination-of-wind-turbines" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/21424.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">5186</span> Study of Rayleigh-Bénard-Brinkman Convection Using LTNE Model and Coupled, Real Ginzburg-Landau Equations</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=P.%20G.%20Siddheshwar">P. G. Siddheshwar</a>, <a href="https://publications.waset.org/abstracts/search?q=R.%20K.%20Vanishree"> R. K. Vanishree</a>, <a href="https://publications.waset.org/abstracts/search?q=C.%20Kanchana"> C. Kanchana</a> </p> <p class="card-text"><strong>Abstract:</strong></p> A local nonlinear stability analysis using a eight-mode expansion is performed in arriving at the coupled amplitude equations for Rayleigh-Bénard-Brinkman convection (RBBC) in the presence of LTNE effects. Streamlines and isotherms are obtained in the two-dimensional unsteady finite-amplitude convection regime. The parameters’ influence on heat transport is found to be more pronounced at small time than at long times. Results of the Rayleigh-Bénard convection is obtained as a particular case of the present study. Additional modes are shown not to significantly influence the heat transport thus leading us to infer that five minimal modes are sufficient to make a study of RBBC. The present problem that uses rolls as a pattern of manifestation of instability is a needed first step in the direction of making a very general non-local study of two-dimensional unsteady convection. The results may be useful in determining the preferred range of parameters’ values while making rheometric measurements in fluids to ascertain fluid properties such as viscosity. The results of LTE are obtained as a limiting case of the results of LTNE obtained in the paper. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=coupled%20Ginzburg%E2%80%93Landau%20model" title="coupled Ginzburg–Landau model">coupled Ginzburg–Landau model</a>, <a href="https://publications.waset.org/abstracts/search?q=local%20thermal%20non-equilibrium%20%28LTNE%29" title=" local thermal non-equilibrium (LTNE)"> local thermal non-equilibrium (LTNE)</a>, <a href="https://publications.waset.org/abstracts/search?q=local%20thermal%20equilibrium%20%28LTE%29" title=" local thermal equilibrium (LTE)"> local thermal equilibrium (LTE)</a>, <a href="https://publications.waset.org/abstracts/search?q=Rayleigh%E2%80%93B%C3%A9nard-Brinkman%20convection" title=" Rayleigh–Bénard-Brinkman convection"> Rayleigh–Bénard-Brinkman convection</a> </p> <a href="https://publications.waset.org/abstracts/70182/study-of-rayleigh-benard-brinkman-convection-using-ltne-model-and-coupled-real-ginzburg-landau-equations" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/70182.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">237</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">5185</span> Application of Lattice Boltzmann Method to Different Boundary Conditions in a Two Dimensional Enclosure</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Jean%20Yves%20Trepanier">Jean Yves Trepanier</a>, <a href="https://publications.waset.org/abstracts/search?q=Sami%20Ammar"> Sami Ammar</a>, <a href="https://publications.waset.org/abstracts/search?q=Sagnik%20Banik"> Sagnik Banik</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Lattice Boltzmann Method has been advantageous in simulating complex boundary conditions and solving for fluid flow parameters by streaming and collision processes. This paper includes the study of three different test cases in a confined domain using the method of the Lattice Boltzmann model. 1. An SRT (Single Relaxation Time) approach in the Lattice Boltzmann model is used to simulate Lid Driven Cavity flow for different Reynolds Number (100, 400 and 1000) with a domain aspect ratio of 1, i.e., square cavity. A moment-based boundary condition is used for more accurate results. 2. A Thermal Lattice BGK (Bhatnagar-Gross-Krook) Model is developed for the Rayleigh Benard convection for both test cases - Horizontal and Vertical Temperature difference, considered separately for a Boussinesq incompressible fluid. The Rayleigh number is varied for both the test cases (10^3 ≤ Ra ≤ 10^6) keeping the Prandtl number at 0.71. A stability criteria with a precise forcing scheme is used for a greater level of accuracy. 3. The phase change problem governed by the heat-conduction equation is studied using the enthalpy based Lattice Boltzmann Model with a single iteration for each time step, thus reducing the computational time. A double distribution function approach with D2Q9 (density) model and D2Q5 (temperature) model are used for two different test cases-the conduction dominated melting and the convection dominated melting. The solidification process is also simulated using the enthalpy based method with a single distribution function using the D2Q5 model to provide a better understanding of the heat transport phenomenon. The domain for the test cases has an aspect ratio of 2 with some exceptions for a square cavity. An approximate velocity scale is chosen to ensure that the simulations are within the incompressible regime. Different parameters like velocities, temperature, Nusselt number, etc. are calculated for a comparative study with the existing works of literature. The simulated results demonstrate excellent agreement with the existing benchmark solution within an error limit of ± 0.05 implicates the viability of this method for complex fluid flow problems. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=BGK" title="BGK">BGK</a>, <a href="https://publications.waset.org/abstracts/search?q=Nusselt" title=" Nusselt"> Nusselt</a>, <a href="https://publications.waset.org/abstracts/search?q=Prandtl" title=" Prandtl"> Prandtl</a>, <a href="https://publications.waset.org/abstracts/search?q=Rayleigh" title=" Rayleigh"> Rayleigh</a>, <a href="https://publications.waset.org/abstracts/search?q=SRT" title=" SRT"> SRT</a> </p> <a href="https://publications.waset.org/abstracts/111825/application-of-lattice-boltzmann-method-to-different-boundary-conditions-in-a-two-dimensional-enclosure" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/111825.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">128</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">5184</span> The Rayleigh Quotient for Structural Element Vibration Analysis with Finite Element Method</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Falek%20Kamel">Falek Kamel</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Various approaches are usually used in the dynamic analysis of beams vibrating transversally. For this, numerical methods allowing the solving of the general eigenvalue problem are utilized. The equilibrium equations describe the movement resulting from the solution of a fourth-order differential equation. Our investigation is based on the finite element method. The findings of these investigations are the vibration frequencies obtained by the Jacobi method. Two types of the elementary mass matrix are considered, representing a uniform distribution of the mass along with the element and concentrated ones located at fixed points whose number is increased progressively separated by equal distances at each evaluation stage. The studied beams have different boundary constraints representing several classical situations. Comparisons are made for beams where the distributed mass is replaced by n concentrated masses. As expected, the first calculus stage is to obtain the lowest number of beam parts that gives a frequency comparable to that issued from the Rayleigh formula. The obtained values are then compared to theoretical results based on the assumptions of the Bernoulli-Euler theory. These steps are used for the second type of mass representation in the same manner. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=structural%20elements" title="structural elements">structural elements</a>, <a href="https://publications.waset.org/abstracts/search?q=beams%20vibrating" title=" beams vibrating"> beams vibrating</a>, <a href="https://publications.waset.org/abstracts/search?q=dynamic%20analysis" title=" dynamic analysis"> dynamic analysis</a>, <a href="https://publications.waset.org/abstracts/search?q=finite%20element%20method" title=" finite element method"> finite element method</a>, <a href="https://publications.waset.org/abstracts/search?q=Jacobi%20method" title=" Jacobi method"> Jacobi method</a> </p> <a href="https://publications.waset.org/abstracts/141449/the-rayleigh-quotient-for-structural-element-vibration-analysis-with-finite-element-method" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/141449.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">163</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=Rayleigh%20distribution&page=2">2</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=Rayleigh%20distribution&page=3">3</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=Rayleigh%20distribution&page=4">4</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=Rayleigh%20distribution&page=5">5</a></li> <li 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