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equations</title> <meta name="description" content="Search results for: dispersion equations"> <meta name="keywords" content="dispersion equations"> <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 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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="dispersion equations"> <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> 2457</div> </div> </div> </div> <h1 class="mt-3 mb-3 text-center" style="font-size:1.6rem;">Search results for: dispersion equations</h1> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">2457</span> Effects of Variable Properties and Double Dispersion on Magnetohydrodynamic (MHD) Mixed Convection in a Power-Law Fluid Saturated Non-Darcy Porous Medium</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Pranitha%20Janapatla">Pranitha Janapatla</a>, <a href="https://publications.waset.org/abstracts/search?q=Venkata%20Suman%20Gontla"> Venkata Suman Gontla</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The present paper investigates the effects of MHD, double dispersion and variable properties on mixed convection flow from a vertical surface in a power-law fluid saturated non-Darcy porous medium. The governing non-linear partial differential equations are reduced to a system of ordinary differential equations by using a special form of Lie group transformations viz. scaling group of transformations. These ordinary differential equations are solved numerically by using Shooting technique. The influence of relevant parameters on the non-dimensional velocity, temperature, concentration for pseudo-plastic fluid, Newtonian and dilatant fluid are discussed and displayed graphically. The behavior of heat and mass transfer coefficients are shown in tabular form. Comparisons with the published works are performed and are found to be in very good agreement. From this analysis, it is observed that an increase in variable viscosity causes to decrease in velocity profile and increase the temperature and concentration distributions. It is also concluded that increase in the solutal dispersion decreases the velocity and concentration but raises the temperature profile. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=power-law%20fluid" title="power-law fluid">power-law fluid</a>, <a href="https://publications.waset.org/abstracts/search?q=thermal%20conductivity" title=" thermal conductivity"> thermal conductivity</a>, <a href="https://publications.waset.org/abstracts/search?q=thermal%20dispersion" title=" thermal dispersion"> thermal dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=solutal%20dispersion" title=" solutal dispersion"> solutal dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=variable%20viscosity" title=" variable viscosity"> variable viscosity</a> </p> <a href="https://publications.waset.org/abstracts/54707/effects-of-variable-properties-and-double-dispersion-on-magnetohydrodynamic-mhd-mixed-convection-in-a-power-law-fluid-saturated-non-darcy-porous-medium" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/54707.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">231</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">2456</span> Analytical Solutions of Time Space Fractional, Advection-Dispersion and Whitham-Broer-Kaup Equations</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Muhammad%20Danish%20Khan">Muhammad Danish Khan</a>, <a href="https://publications.waset.org/abstracts/search?q=Imran%20Naeem"> Imran Naeem</a>, <a href="https://publications.waset.org/abstracts/search?q=Mudassar%20Imran"> Mudassar Imran</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this article, we study time-space Fractional Advection-Dispersion (FADE) equation and time-space Fractional Whitham-Broer-Kaup (FWBK) equation that have a significant role in hydrology. We introduce suitable transformations to convert fractional order derivatives to integer order derivatives and as a result these equations transform into Partial Differential Equations (PDEs). Then the Lie symmetries and corresponding optimal systems of the resulting PDEs are derived. The symmetry reductions and exact independent solutions based on optimal system are investigated which constitute the exact solutions of original fractional differential equations. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=modified%20Riemann-Liouville%20fractional%20derivative" title="modified Riemann-Liouville fractional derivative">modified Riemann-Liouville fractional derivative</a>, <a href="https://publications.waset.org/abstracts/search?q=lie-symmetries" title=" lie-symmetries"> lie-symmetries</a>, <a href="https://publications.waset.org/abstracts/search?q=optimal%20system" title=" optimal system"> optimal system</a>, <a href="https://publications.waset.org/abstracts/search?q=invariant%20solutions" title=" invariant solutions"> invariant solutions</a> </p> <a href="https://publications.waset.org/abstracts/2191/analytical-solutions-of-time-space-fractional-advection-dispersion-and-whitham-broer-kaup-equations" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/2191.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">431</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">2455</span> Equations of Pulse Propagation in Three-Layer Structure of As2S3 Chalcogenide Plasmonic Nano-Waveguides</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Leila%20Motamed-Jahromi">Leila Motamed-Jahromi</a>, <a href="https://publications.waset.org/abstracts/search?q=Mohsen%20Hatami"> Mohsen Hatami</a>, <a href="https://publications.waset.org/abstracts/search?q=Alireza%20Keshavarz"> Alireza Keshavarz </a> </p> <p class="card-text"><strong>Abstract:</strong></p> This research aims at obtaining the equations of pulse propagation in nonlinear plasmonic waveguides created with As<sub>2</sub>S<sub>3</sub> chalcogenide materials. Via utilizing Helmholtz equation and first-order perturbation theory, two components of electric field are determined within frequency domain. Afterwards, the equations are formulated in time domain. The obtained equations include two coupled differential equations that considers nonlinear dispersion<span dir="RTL">.</span> <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=nonlinear%20optics" title="nonlinear optics">nonlinear optics</a>, <a href="https://publications.waset.org/abstracts/search?q=plasmonic%20waveguide" title=" plasmonic waveguide"> plasmonic waveguide</a>, <a href="https://publications.waset.org/abstracts/search?q=chalcogenide" title=" chalcogenide"> chalcogenide</a>, <a href="https://publications.waset.org/abstracts/search?q=propagation%20equation" title=" propagation equation"> propagation equation</a> </p> <a href="https://publications.waset.org/abstracts/52758/equations-of-pulse-propagation-in-three-layer-structure-of-as2s3-chalcogenide-plasmonic-nano-waveguides" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/52758.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">417</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">2454</span> Designing a Dispersion Flattened Single Mode PCF for E-Band to U-Band with Less Effective Area</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Shabbir%20Chowdhury">Shabbir Chowdhury</a> </p> <p class="card-text"><strong>Abstract:</strong></p> A signal is broadened when it is gone through a channel, this phenomenon is known as dispersion. And dispersion is different for different wavelength. So bandwidth become limited. Research have tried to design an optical fiber with flattened dispersion to use more bandwidth and also for wavelength division multiplexing. In this paper, a single mode photonic crystal fiber with a flattened dispersion and less effective area has been proposed where silica is used as fiber materials. The effective dispersion varies from -1.996 to 0.1783 [ps/(nm-km)] for enter E-band to U-band. This fiber will take only 3.048 [micrometer^2] (for 1.75 micrometer wavelength). Silica is being used as the fiber material. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=photonic%20crystal%20fiber" title="photonic crystal fiber">photonic crystal fiber</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion" title=" dispersion"> dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=bandwidth" title=" bandwidth"> bandwidth</a>, <a href="https://publications.waset.org/abstracts/search?q=chromatic%20dispersion" title=" chromatic dispersion"> chromatic dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=effective%20dispersion" title=" effective dispersion"> effective dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion%20compensation" title=" dispersion compensation"> dispersion compensation</a>, <a href="https://publications.waset.org/abstracts/search?q=effective%20area" title=" effective area"> effective area</a>, <a href="https://publications.waset.org/abstracts/search?q=effective%20refractive%20index" title=" effective refractive index"> effective refractive index</a> </p> <a href="https://publications.waset.org/abstracts/51092/designing-a-dispersion-flattened-single-mode-pcf-for-e-band-to-u-band-with-less-effective-area" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/51092.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">415</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">2453</span> Study of Ultrasonic Waves in Unidirectional Fiber-Reinforced Composite Plates for the Aerospace Applications</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=DucTho%20Le">DucTho Le</a>, <a href="https://publications.waset.org/abstracts/search?q=Duy%20Kien%20Dao"> Duy Kien Dao</a>, <a href="https://publications.waset.org/abstracts/search?q=Quoc%20Tinh%20Bui"> Quoc Tinh Bui</a>, <a href="https://publications.waset.org/abstracts/search?q=Haidang%20Phan"> Haidang Phan</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The article is concerned with the motion of ultrasonic guided waves in a unidirectional fiber-reinforced composite plate under acoustic sources. Such unidirectional composite material has orthotropic elastic properties as it is very stiff along the fibers and rather compliant across the fibers. The dispersion equations of free Lamb waves propagating in an orthotropic layer are derived that results in the dispersion curves. The connection of these equations to the Rayleigh-Lamb frequency relations of isotropic plates is discussed. By the use of reciprocity in elastodynamics, closed-form solutions of elastic wave motions subjected to time-harmonic loads in the layer are computed in a simple manner. We also consider the problem of Lamb waves generated by a set of time-harmonic sources. The obtained computations can be very useful for developing ultrasound-based methods for nondestructive evaluation of composite structures. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=lamb%20waves" title="lamb waves">lamb waves</a>, <a href="https://publications.waset.org/abstracts/search?q=fiber-reinforced%20composite%20plates" title=" fiber-reinforced composite plates"> fiber-reinforced composite plates</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion%20equations" title=" dispersion equations"> dispersion equations</a>, <a href="https://publications.waset.org/abstracts/search?q=nondestructive%20evaluation" title=" nondestructive evaluation"> nondestructive evaluation</a>, <a href="https://publications.waset.org/abstracts/search?q=reciprocity%20theorems" title=" reciprocity theorems"> reciprocity theorems</a> </p> <a href="https://publications.waset.org/abstracts/110250/study-of-ultrasonic-waves-in-unidirectional-fiber-reinforced-composite-plates-for-the-aerospace-applications" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/110250.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">149</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">2452</span> Lamb Waves in Plates Subjected to Uniaxial Stresses</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Munawwar%20Mohabuth">Munawwar Mohabuth</a>, <a href="https://publications.waset.org/abstracts/search?q=Andrei%20Kotousov"> Andrei Kotousov</a>, <a href="https://publications.waset.org/abstracts/search?q=Ching-Tai%20Ng"> Ching-Tai Ng</a> </p> <p class="card-text"><strong>Abstract:</strong></p> On the basis of the finite deformation theory, the effect of homogeneous stress on the propagation of Lamb waves in an initially isotropic hyperelastic plate is analysed. The equations governing the propagation of small amplitude waves in the prestressed plate are derived using the theory of small deformations superimposed on large deformations. By enforcing traction free boundary conditions at the upper and lower surfaces of the plate, acoustoelastic dispersion equations for Lamb wave propagation are obtained, which are solved numerically. Results are given for an aluminum plate subjected to a range of applied stresses. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=acoustoelasticity" title="acoustoelasticity">acoustoelasticity</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion" title=" dispersion"> dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=finite%20deformation" title=" finite deformation"> finite deformation</a>, <a href="https://publications.waset.org/abstracts/search?q=lamb%20waves" title=" lamb waves"> lamb waves</a> </p> <a href="https://publications.waset.org/abstracts/32316/lamb-waves-in-plates-subjected-to-uniaxial-stresses" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/32316.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">468</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">2451</span> Combination Rule for Homonuclear Dipole Dispersion Coefficients</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Giorgio%20Visentin">Giorgio Visentin</a>, <a href="https://publications.waset.org/abstracts/search?q=Inna%20S.%20Kalinina"> Inna S. Kalinina</a>, <a href="https://publications.waset.org/abstracts/search?q=Alexei%20A.%20Buchachenko"> Alexei A. Buchachenko</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In the ambit of intermolecular interactions, a combination rule is defined as a relation linking a potential parameter for the interaction of two unlike species with the same parameters for interaction pairs of like species. Some of their most exemplificative applications cover the construction of molecular dynamics force fields and dispersion-corrected density functionals. Here, an extended combination rule is proposed, relating the dipole-dipole dispersion coefficients for the interaction of like target species to the same coefficients for the interaction of the target and a set of partner species. The rule can be devised in two different ways, either by uniform discretization of the Casimir-Polder integral on a Gauss-Legendre quadrature or by relating the dynamic polarizabilities of the target and the partner species. Both methods return the same system of linear equations, which requires the knowledge of the dispersion coefficients for interaction between the partner species to be solved. The test examples show a high accuracy for dispersion coefficients (better than 1% in the pristine test for the interaction of Yb atom with rare gases and alkaline-earth metal atoms). In contrast, the rule does not ensure correct monotonic behavior of the dynamic polarizability of the target species. Acknowledgment: The work is supported by Russian Science Foundation grant # 17-13-01466. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=combination%20rule" title="combination rule">combination rule</a>, <a href="https://publications.waset.org/abstracts/search?q=dipole-dipole%20dispersion%20coefficient" title=" dipole-dipole dispersion coefficient"> dipole-dipole dispersion coefficient</a>, <a href="https://publications.waset.org/abstracts/search?q=Casimir-Polder%20integral" title=" Casimir-Polder integral"> Casimir-Polder integral</a>, <a href="https://publications.waset.org/abstracts/search?q=Gauss-Legendre%20quadrature" title=" Gauss-Legendre quadrature"> Gauss-Legendre quadrature</a> </p> <a href="https://publications.waset.org/abstracts/130113/combination-rule-for-homonuclear-dipole-dispersion-coefficients" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/130113.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">178</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">2450</span> Estimation of Longitudinal Dispersion Coefficient Using Tracer Data</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=K.%20Ebrahimi">K. Ebrahimi</a>, <a href="https://publications.waset.org/abstracts/search?q=Sh.%20Shahid"> Sh. Shahid</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20Mohammadi%20Ghaleni"> M. Mohammadi Ghaleni</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20H.%20Omid"> M. H. Omid</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The longitudinal dispersion coefficient is a crucial parameter for 1-D water quality analysis of riverine flows. So far, different types of empirical equations for estimation of the coefficient have been developed, based on various case studies. The main objective of this paper is to develop an empirical equation for estimation of the coefficient for a riverine flow. For this purpose, a set of tracer experiments was conducted, involving salt tracer, at three sections located in downstream of a lengthy canal. Tracer data were measured in three mixing lengths along the canal including; 45, 75 and 100m. According to the results, the obtained coefficients from new developed empirical equation gave an encouraging level of agreement with the theoretical values. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=coef%EF%AC%81cients" title="coefﬁcients">coefﬁcients</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion" title=" dispersion"> dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=river" title=" river"> river</a>, <a href="https://publications.waset.org/abstracts/search?q=tracer" title=" tracer"> tracer</a>, <a href="https://publications.waset.org/abstracts/search?q=water%20quality" title=" water quality"> water quality</a> </p> <a href="https://publications.waset.org/abstracts/31418/estimation-of-longitudinal-dispersion-coefficient-using-tracer-data" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/31418.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">389</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">2449</span> Evaluation of the Adsorption Adaptability of Activated Carbon Using Dispersion Force</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Masao%20Fujisawa">Masao Fujisawa</a>, <a href="https://publications.waset.org/abstracts/search?q=Hirohito%20Ikeda"> Hirohito Ikeda</a>, <a href="https://publications.waset.org/abstracts/search?q=Tomonori%20Ohata"> Tomonori Ohata</a>, <a href="https://publications.waset.org/abstracts/search?q=Miho%20Yukawa"> Miho Yukawa</a>, <a href="https://publications.waset.org/abstracts/search?q=Hatsumi%20Aki"> Hatsumi Aki</a>, <a href="https://publications.waset.org/abstracts/search?q=Takayoshi%20Kimura"> Takayoshi Kimura</a> </p> <p class="card-text"><strong>Abstract:</strong></p> We attempted to predict adsorption coefficients by utilizing dispersion energies. We performed liquid-phase free energy calculations based on gas-phase geometries of organic compounds using the DFT and studied the relationship between the adsorption of organic compounds by activated carbon and dispersion energies of the organic compounds. A linear correlation between absorption coefficients and dispersion energies was observed. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=activated%20carbon" title="activated carbon">activated carbon</a>, <a href="https://publications.waset.org/abstracts/search?q=adsorption" title=" adsorption"> adsorption</a>, <a href="https://publications.waset.org/abstracts/search?q=prediction" title=" prediction"> prediction</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion%20energy" title=" dispersion energy"> dispersion energy</a> </p> <a href="https://publications.waset.org/abstracts/50573/evaluation-of-the-adsorption-adaptability-of-activated-carbon-using-dispersion-force" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/50573.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">233</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">2448</span> Characterization of the Dispersion Phenomenon in an Optical Biosensor</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=An-Shik%20Yang">An-Shik Yang</a>, <a href="https://publications.waset.org/abstracts/search?q=Chin-Ting%20Kuo"> Chin-Ting Kuo</a>, <a href="https://publications.waset.org/abstracts/search?q=Yung-Chun%20Yang"> Yung-Chun Yang</a>, <a href="https://publications.waset.org/abstracts/search?q=Wen-Hsin%20Hsieh"> Wen-Hsin Hsieh</a>, <a href="https://publications.waset.org/abstracts/search?q=Chiang-Ho%20Cheng"> Chiang-Ho Cheng</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Optical biosensors have become a powerful detection and analysis tool for wide-ranging applications in biomedical research, pharmaceuticals and environmental monitoring. This study carried out the computational fluid dynamics (CFD)-based simulations to explore the dispersion phenomenon in the microchannel of a optical biosensor. The predicted time sequences of concentration contours were utilized to better understand the dispersion development occurred in different geometric shapes of microchannels. The simulation results showed the surface concentrations at the sensing probe (with the best performance of a grating coupler) in respect of time to appraise the dispersion effect and therefore identify the design configurations resulting in minimum dispersion. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=CFD%20simulations" title="CFD simulations">CFD simulations</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion" title=" dispersion"> dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=microfluidic" title=" microfluidic"> microfluidic</a>, <a href="https://publications.waset.org/abstracts/search?q=optical%20waveguide%20sensors" title=" optical waveguide sensors"> optical waveguide sensors</a> </p> <a href="https://publications.waset.org/abstracts/24715/characterization-of-the-dispersion-phenomenon-in-an-optical-biosensor" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/24715.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">545</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">2447</span> Modeling and Computational Validation of Dispersion Curves of Guide Waves in a Pipe Using ANSYS</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=A.%20Perdomo">A. Perdomo</a>, <a href="https://publications.waset.org/abstracts/search?q=J.%20R.%20Bacca"> J. R. Bacca</a>, <a href="https://publications.waset.org/abstracts/search?q=Q.%20E.%20Jabid"> Q. E. Jabid</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In recent years, technological and investigative progress has been achieved in the area of monitoring of equipment and installation as a result of a deeper understanding of physical phenomenon associated with the non-destructive tests (NDT). The modal analysis proposes an efficient solution to determine the dispersion curves of an arbitrary waveguide cross-sectional. Dispersion curves are essential in the discontinuity localization based on guided waves. In this work, an isotropic hollow cylinder is dynamically analyzed in ANSYS to obtain resonant frequencies and mode shapes all of them associated with the dispersion curves. The numerical results provide the relation between frequency and wavelength which is the foundation of the dispersion curves. Results of the simulation process are validated with the software GUIGW. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=ansys%20APDL" title="ansys APDL">ansys APDL</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion%20curves" title=" dispersion curves"> dispersion curves</a>, <a href="https://publications.waset.org/abstracts/search?q=guide%20waves" title=" guide waves"> guide waves</a>, <a href="https://publications.waset.org/abstracts/search?q=modal%20analysis" title=" modal analysis"> modal analysis</a> </p> <a href="https://publications.waset.org/abstracts/108272/modeling-and-computational-validation-of-dispersion-curves-of-guide-waves-in-a-pipe-using-ansys" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/108272.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">253</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">2446</span> Implication of the Exchange-Correlation on Electromagnetic Wave Propagation in Single-Wall Carbon Nanotubes</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=A.%20Abdikian">A. Abdikian</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Using the linearized quantum hydrodynamic model (QHD) and by considering the role of quantum parameter (Bohm’s potential) and electron exchange-correlation potential in conjunction with Maxwell’s equations, electromagnetic wave propagation in a single-walled carbon nanotubes was studied. The electronic excitations are described. By solving the mentioned equations with appropriate boundary conditions and by assuming the low-frequency electromagnetic waves, two general expressions of dispersion relations are derived for the transverse magnetic (TM) and transverse electric (TE) modes, respectively. The dispersion relations are analyzed numerically and it was found that the dependency of dispersion curves with the exchange-correlation effects (which have been ignored in previous works) in the low frequency would be limited. Moreover, it has been realized that asymptotic behaviors of the TE and TM modes are similar in single wall carbon nanotubes (SWCNTs). The results show that by adding the function of electron exchange-correlation potential lead to the phenomena and make to extend the validity range of QHD model. The results can be important in the study of collective phenomena in nanostructures. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=transverse%20magnetic" title="transverse magnetic">transverse magnetic</a>, <a href="https://publications.waset.org/abstracts/search?q=transverse%20electric" title=" transverse electric"> transverse electric</a>, <a href="https://publications.waset.org/abstracts/search?q=quantum%20hydrodynamic%20model" title=" quantum hydrodynamic model"> quantum hydrodynamic model</a>, <a href="https://publications.waset.org/abstracts/search?q=electron%20exchange-correlation%20potential" title=" electron exchange-correlation potential"> electron exchange-correlation potential</a>, <a href="https://publications.waset.org/abstracts/search?q=single-wall%20carbon%20nanotubes" title=" single-wall carbon nanotubes"> single-wall carbon nanotubes</a> </p> <a href="https://publications.waset.org/abstracts/69939/implication-of-the-exchange-correlation-on-electromagnetic-wave-propagation-in-single-wall-carbon-nanotubes" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/69939.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">2445</span> Effect of Homogeneous and Heterogeneous Chemical Reactions on Peristaltic Flow of a Jeffrey Fluid in an Asymmetric Channel</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=G.%20Ravi%20Kiran">G. Ravi Kiran</a>, <a href="https://publications.waset.org/abstracts/search?q=G.%20Radhakrishnamacharya"> G. Radhakrishnamacharya</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this paper, the dispersion of a solute in the peristaltic flow of a Jeffrey fluid in the presence of both homogeneous and heterogeneous chemical reactions has been discussed. The average effective dispersion coefficient has been found using Taylor's limiting condition under long wavelength approximation. It is observed that the average dispersion coefficient increases with amplitude ratio which implies that dispersion is more in the presence of peristalsis. The average effective dispersion coefficient increases with Jeffrey parameter in the cases of both homogeneous and combined homogeneous and heterogeneous chemical reactions. Further, dispersion decreases with a phase difference, homogeneous reaction rate parameters, and heterogeneous reaction rate parameter. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=peristalsis" title="peristalsis">peristalsis</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion" title=" dispersion"> dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=chemical%20reaction" title=" chemical reaction"> chemical reaction</a>, <a href="https://publications.waset.org/abstracts/search?q=Jeffrey%20fluid" title=" Jeffrey fluid"> Jeffrey fluid</a>, <a href="https://publications.waset.org/abstracts/search?q=asymmetric%20channel" title=" asymmetric channel"> asymmetric channel</a> </p> <a href="https://publications.waset.org/abstracts/18706/effect-of-homogeneous-and-heterogeneous-chemical-reactions-on-peristaltic-flow-of-a-jeffrey-fluid-in-an-asymmetric-channel" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/18706.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">587</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">2444</span> Guided Wave in a Cylinder with Trepezoid Cross-Section</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Nan%20Tang">Nan Tang</a>, <a href="https://publications.waset.org/abstracts/search?q=Bin%20Wu"> Bin Wu</a>, <a href="https://publications.waset.org/abstracts/search?q=Cunfu%20He"> Cunfu He</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The trapezoid rods are widely used in civil engineering as load –carrying members. Ultrasonic guided wave is one of the most popular techniques in analyzing the propagation of elastic guided wave. The goal of this paper is to investigate the propagation of elastic waves in the isotropic bar with trapezoid cross-section. Dispersion curves that describe the relationship between the frequency and velocity provide the fundamental information to describe the propagation of elastic waves through a structure. Based on the SAFE (semi-analytical finite element) a linear algebraic system of equations is obtained. By using numerical methods, dispersion curves solved for the rods with the trapezoid cross-section. These fundamental information plays an important role in applying ultrasonic guided waves to NTD for structures with trapezoid cross section. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=guided%20wave" title="guided wave">guided wave</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion" title=" dispersion"> dispersion</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=trapezoid%20rod" title=" trapezoid rod"> trapezoid rod</a> </p> <a href="https://publications.waset.org/abstracts/30839/guided-wave-in-a-cylinder-with-trepezoid-cross-section" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/30839.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">292</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">2443</span> Modeling Solute Transport through Porous Media with Scale Dependent Dispersion</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Teodrose%20Atnafu%20Abegaze">Teodrose Atnafu Abegaze</a>, <a href="https://publications.waset.org/abstracts/search?q=P.%20K.%20Sharma"> P. K. Sharma</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this study, an attempt has been made to study the behavior of breakthrough curves in both layered and mixed heterogeneous soil by conducting experiments in long soil columns. Sodium chloride has been used as a conservative tracer in the experiment. Advective dispersive transport equations, including equilibrium sorption and first-order degradation coefficients, are used for solute transport through mobile-immobile porous media. In order to do the governing equation for solute transport, there are explicit and implicit schemes for our condition; we use an implicit scheme to numerically model the solute concentration. Results of experimental breakthrough curves indicate that the behavior of observed breakthrough curves is approximately similar in both cases of layered and mixed soil, while earlier arrival of solute concentration is obtained in the case of mixed soil. It means that the types of heterogeneity of the soil media affect the behavior of solute concentration. Finally, it is also shown that the asymptotic dispersion model simulates the experimental data better than the constant and linear distance-dependent dispersion models. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=numerical%20method" title="numerical method">numerical method</a>, <a href="https://publications.waset.org/abstracts/search?q=distance%20dependant%20dispersion" title=" distance dependant dispersion"> distance dependant dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=reactive%20transport" title=" reactive transport"> reactive transport</a>, <a href="https://publications.waset.org/abstracts/search?q=experiment" title=" experiment"> experiment</a> </p> <a href="https://publications.waset.org/abstracts/179547/modeling-solute-transport-through-porous-media-with-scale-dependent-dispersion" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/179547.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">63</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">2442</span> Influence of Chirp of High-Speed Laser Diodes and Fiber Dispersion on Performance of Non-Amplified 40-Gbps Optical Fiber Links</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ahmed%20Bakry">Ahmed Bakry</a>, <a href="https://publications.waset.org/abstracts/search?q=Moustafa%20Ahmed"> Moustafa Ahmed</a> </p> <p class="card-text"><strong>Abstract:</strong></p> We model and simulate the combined effect of fiber dispersion and frequency chirp of a directly modulated high-speed laser diode on the figures of merit of a non-amplified 40-Gbps optical fiber link. We consider both the return to zero (RZ) and non-return to zero (NRZ) patterns of the pseudorandom modulation bits. The performance of the fiber communication system is assessed by the fiber-length limitation due to the fiber dispersion. We study the influence of replacing standard single-mode fibers by non-zero dispersion-shifted fibers on the maximum fiber length and evaluate the associated power penalty. We introduce new dispersion tolerances for 1-dB power penalty of the RZ and NRZ 40-Gbps optical fiber links. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=bit%20error%20rate" title="bit error rate">bit error rate</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion" title=" dispersion"> dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=frequency%20chirp" title=" frequency chirp"> frequency chirp</a>, <a href="https://publications.waset.org/abstracts/search?q=fiber%20communications" title=" fiber communications"> fiber communications</a>, <a href="https://publications.waset.org/abstracts/search?q=semiconductor%20laser" title=" semiconductor laser"> semiconductor laser</a> </p> <a href="https://publications.waset.org/abstracts/10587/influence-of-chirp-of-high-speed-laser-diodes-and-fiber-dispersion-on-performance-of-non-amplified-40-gbps-optical-fiber-links" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/10587.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">641</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">2441</span> Effect of Viscosity on Propagation of MHD Waves in Astrophysical Plasma</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Alemayehu%20Mengesha">Alemayehu Mengesha</a>, <a href="https://publications.waset.org/abstracts/search?q=Solomon%20Belay"> Solomon Belay</a> </p> <p class="card-text"><strong>Abstract:</strong></p> We determine the general dispersion relation for the propagation of magnetohydrodynamic (MHD) waves in an astrophysical plasma by considering the effect of viscosity with an anisotropic pressure tensor. Basic MHD equations have been derived and linearized by the method of perturbation to develop the general form of the dispersion relation equation. Our result indicates that an astrophysical plasma with an anisotropic pressure tensor is stable in the presence of viscosity and a strong magnetic field at considerable wavelength. Currently, we are doing the numerical analysis of this work. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=astrophysical" title="astrophysical">astrophysical</a>, <a href="https://publications.waset.org/abstracts/search?q=magnetic%20field" title=" magnetic field"> magnetic field</a>, <a href="https://publications.waset.org/abstracts/search?q=instability" title=" instability"> instability</a>, <a href="https://publications.waset.org/abstracts/search?q=MHD" title=" MHD"> MHD</a>, <a href="https://publications.waset.org/abstracts/search?q=wavelength" title=" wavelength"> wavelength</a>, <a href="https://publications.waset.org/abstracts/search?q=viscosity" title=" viscosity"> viscosity</a> </p> <a href="https://publications.waset.org/abstracts/47904/effect-of-viscosity-on-propagation-of-mhd-waves-in-astrophysical-plasma" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/47904.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">343</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">2440</span> Effects of Dispersion on Peristaltic Flow of a Micropolar Fluid Through a Porous Medium with Wall Effects in the Presence of Slip</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=G.%20Ravi%20Kiran">G. Ravi Kiran</a>, <a href="https://publications.waset.org/abstracts/search?q=G.%20Radhakrishnamacharya"> G. Radhakrishnamacharya</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper investigates the effects of slip boundary condition and wall properties on the dispersion of a solute matter in peristaltic flow of an incompressible micropolar fluid through a porous medium. Long wavelength approximation, Taylor's limiting condition and dynamic boundary conditions at the flexible walls are used to obtain the average effective dispersion coefficient in the presence of combined homogeneous and heterogeneous chemical reactions. The effects of various pertinent parameters on the effective dispersion coefficient are discussed. It is observed that peristalsis enhances dispersion. It also increases with micropolar parameter, cross viscosity coefficient, Darcy number, slip parameter and wall parameters. Further, dispersion decreases with homogenous chemical reaction rate and heterogeneous chemical reaction rate. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=chemical%20reaction" title="chemical reaction">chemical reaction</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion" title=" dispersion"> dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=peristalsis" title=" peristalsis"> peristalsis</a>, <a href="https://publications.waset.org/abstracts/search?q=slip%20condition" title=" slip condition"> slip condition</a>, <a href="https://publications.waset.org/abstracts/search?q=wall%20properties" title=" wall properties"> wall properties</a> </p> <a href="https://publications.waset.org/abstracts/24925/effects-of-dispersion-on-peristaltic-flow-of-a-micropolar-fluid-through-a-porous-medium-with-wall-effects-in-the-presence-of-slip" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/24925.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">466</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">2439</span> Evaluating the Validity of CFD Model of Dispersion in a Complex Urban Geometry Using Two Sets of Experimental Measurements</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Mohammad%20R.%20Kavian%20Nezhad">Mohammad R. Kavian Nezhad</a>, <a href="https://publications.waset.org/abstracts/search?q=Carlos%20F.%20Lange"> Carlos F. Lange</a>, <a href="https://publications.waset.org/abstracts/search?q=Brian%20A.%20Fleck"> Brian A. Fleck</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This research presents the validation study of a computational fluid dynamics (CFD) model developed to simulate the scalar dispersion emitted from rooftop sources around the buildings at the University of Alberta North Campus. The ANSYS CFX code was used to perform the numerical simulation of the wind regime and pollutant dispersion by solving the 3D steady Reynolds-averaged Navier-Stokes (RANS) equations on a building-scale high-resolution grid. The validation study was performed in two steps. First, the CFD model performance in 24 cases (eight wind directions and three wind speeds) was evaluated by comparing the predicted flow fields with the available data from the previous measurement campaign designed at the North Campus, using the standard deviation method (SDM), while the estimated results of the numerical model showed maximum average percent errors of approximately 53% and 37% for wind incidents from the North and Northwest, respectively. Good agreement with the measurements was observed for the other six directions, with an average error of less than 30%. In the second step, the reliability of the implemented turbulence model, numerical algorithm, modeling techniques, and the grid generation scheme was further evaluated using the Mock Urban Setting Test (MUST) dispersion dataset. Different statistical measures, including the fractional bias (FB), the geometric mean bias (MG), and the normalized mean square error (NMSE), were used to assess the accuracy of the predicted dispersion field. Our CFD results are in very good agreement with the field measurements. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=CFD" title="CFD">CFD</a>, <a href="https://publications.waset.org/abstracts/search?q=plume%20dispersion" title=" plume dispersion"> plume dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=complex%20urban%20geometry" title=" complex urban geometry"> complex urban geometry</a>, <a href="https://publications.waset.org/abstracts/search?q=validation%20study" title=" validation study"> validation study</a>, <a href="https://publications.waset.org/abstracts/search?q=wind%20flow" title=" wind flow"> wind flow</a> </p> <a href="https://publications.waset.org/abstracts/142973/evaluating-the-validity-of-cfd-model-of-dispersion-in-a-complex-urban-geometry-using-two-sets-of-experimental-measurements" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/142973.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">135</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">2438</span> Classification of Equations of Motion</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Amritpal%20Singh%20Nafria">Amritpal Singh Nafria</a>, <a href="https://publications.waset.org/abstracts/search?q=Rohit%20Sharma"> Rohit Sharma</a>, <a href="https://publications.waset.org/abstracts/search?q=Md.%20Shami%20Ansari"> Md. Shami Ansari</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Up to now only five different equations of motion can be derived from velocity time graph without needing to know the normal and frictional forces acting at the point of contact. In this paper we obtained all possible requisite conditions to be considering an equation as an equation of motion. After that we classified equations of motion by considering two equations as fundamental kinematical equations of motion and other three as additional kinematical equations of motion. After deriving these five equations of motion, we examine the easiest way of solving a wide variety of useful numerical problems. At the end of the paper, we discussed the importance and educational benefits of classification of equations of motion. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=velocity-time%20graph" title="velocity-time graph">velocity-time graph</a>, <a href="https://publications.waset.org/abstracts/search?q=fundamental%20equations" title=" fundamental equations"> fundamental equations</a>, <a href="https://publications.waset.org/abstracts/search?q=additional%20equations" title=" additional equations"> additional equations</a>, <a href="https://publications.waset.org/abstracts/search?q=requisite%20conditions" title=" requisite conditions"> requisite conditions</a>, <a href="https://publications.waset.org/abstracts/search?q=importance%20and%20educational%20benefits" title=" importance and educational benefits"> importance and educational benefits</a> </p> <a href="https://publications.waset.org/abstracts/15102/classification-of-equations-of-motion" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/15102.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">787</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">2437</span> Ultra-Low Chromatic Dispersion, Low Confinement Loss, and Low Nonlinear Effects Index-Guiding Photonic Crystal Fiber </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=S.%20Olyaee">S. Olyaee</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20Seifouri"> M. Seifouri</a>, <a href="https://publications.waset.org/abstracts/search?q=A.%20Nikoosohbat"> A. Nikoosohbat</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20Shams%20Esfand%20Abadi"> M. Shams Esfand Abadi</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Photonic Crystal Fibers (PCFs) can be used in optical communications as transmission lines. For this reason, the PCFs with low confinement loss, low chromatic dispersion, and low nonlinear effects are highly suitable transmission media. In this paper, we introduce a new design of index-guiding photonic crystal fiber (IG-PCF) with ultra-low chromatic dispersion, low nonlinearity effects, and low confinement loss. Relatively low dispersion is achieved in the wavelength range of 1200 to 1600 nm using the proposed design. According to the new structure of IG-PCF presented in this study, the chromatic dispersion slope is -30(ps/km.nm) and the confinement loss reaches below 10-7 dB/km. While in the wavelength range mentioned above at the same time an effective area of more than 50.2μm2 is obtained. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=optical%20communication%20systems" title="optical communication systems">optical communication systems</a>, <a href="https://publications.waset.org/abstracts/search?q=index-guiding" title=" index-guiding"> index-guiding</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion" title=" dispersion"> dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=confinement%20loss" title=" confinement loss"> confinement loss</a>, <a href="https://publications.waset.org/abstracts/search?q=photonic%20crystal%20fiber" title=" photonic crystal fiber"> photonic crystal fiber</a> </p> <a href="https://publications.waset.org/abstracts/20500/ultra-low-chromatic-dispersion-low-confinement-loss-and-low-nonlinear-effects-index-guiding-photonic-crystal-fiber" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/20500.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">609</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">2436</span> Weak Solutions Of Stochastic Fractional Differential Equations</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Lev%20Idels">Lev Idels</a>, <a href="https://publications.waset.org/abstracts/search?q=Arcady%20Ponosov"> Arcady Ponosov</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Stochastic fractional differential equations have recently attracted considerable attention, as they have been used to model real-world processes, which are subject to natural memory effects and measurement uncertainties. Compared to conventional hereditary differential equations, one of the advantages of fractional differential equations is related to more realistic geometric properties of their trajectories that do not intersect in the phase space. In this report, a Peano-like existence theorem for nonlinear stochastic fractional differential equations is proven under very general hypotheses. Several specific classes of equations are checked to satisfy these hypotheses, including delay equations driven by the fractional Brownian motion, stochastic fractional neutral equations and many others. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=delay%20equations" title="delay equations">delay equations</a>, <a href="https://publications.waset.org/abstracts/search?q=operator%20methods" title=" operator methods"> operator methods</a>, <a href="https://publications.waset.org/abstracts/search?q=stochastic%20noise" title=" stochastic noise"> stochastic noise</a>, <a href="https://publications.waset.org/abstracts/search?q=weak%20solutions" title=" weak solutions"> weak solutions</a> </p> <a href="https://publications.waset.org/abstracts/146592/weak-solutions-of-stochastic-fractional-differential-equations" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/146592.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">209</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">2435</span> Integrable Heisenberg Ferromagnet Equations with Self-Consistent Potentials</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Gulgassyl%20Nugmanova">Gulgassyl Nugmanova</a>, <a href="https://publications.waset.org/abstracts/search?q=Zhanat%20Zhunussova"> Zhanat Zhunussova</a>, <a href="https://publications.waset.org/abstracts/search?q=Kuralay%20Yesmakhanova"> Kuralay Yesmakhanova</a>, <a href="https://publications.waset.org/abstracts/search?q=Galya%20Mamyrbekova"> Galya Mamyrbekova</a>, <a href="https://publications.waset.org/abstracts/search?q=Ratbay%20Myrzakulov"> Ratbay Myrzakulov </a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this paper, we consider some integrable Heisenberg Ferromagnet Equations with self-consistent potentials. We study their Lax representations. In particular we derive their equivalent counterparts in the form of nonlinear Schr\"odinger type equations. We present the integrable reductions of the Heisenberg Ferromagnet Equations with self-consistent potentials. These integrable Heisenberg Ferromagnet Equations with self-consistent potentials describe nonlinear waves in ferromagnets with some additional physical fields. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Heisenberg%20Ferromagnet%20equations" title="Heisenberg Ferromagnet equations">Heisenberg Ferromagnet equations</a>, <a href="https://publications.waset.org/abstracts/search?q=soliton%20equations" title=" soliton equations"> soliton equations</a>, <a href="https://publications.waset.org/abstracts/search?q=equivalence" title=" equivalence"> equivalence</a>, <a href="https://publications.waset.org/abstracts/search?q=Lax%20representation" title=" Lax representation"> Lax representation</a> </p> <a href="https://publications.waset.org/abstracts/27440/integrable-heisenberg-ferromagnet-equations-with-self-consistent-potentials" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/27440.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">457</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">2434</span> CFD Modeling of Pollutant Dispersion in a Free Surface Flow</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Sonia%20Ben%20Hamza">Sonia Ben Hamza</a>, <a href="https://publications.waset.org/abstracts/search?q=Sabra%20Habli"> Sabra Habli</a>, <a href="https://publications.waset.org/abstracts/search?q=Nejla%20Mahjoub%20Said"> Nejla Mahjoub Said</a>, <a href="https://publications.waset.org/abstracts/search?q=Herv%C3%A9%20Bournot"> Hervé Bournot</a>, <a href="https://publications.waset.org/abstracts/search?q=Georges%20Le%20Palec"> Georges Le Palec</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this work, we determine the turbulent dynamic structure of pollutant dispersion in two-phase free surface flow. The numerical simulation was performed using ANSYS Fluent. The flow study is three-dimensional, unsteady and isothermal. The study area has been endowed with a rectangular obstacle to analyze its influence on the hydrodynamic variables and progression of the pollutant. The numerical results show that the hydrodynamic model provides prediction of the dispersion of a pollutant in an open channel flow and reproduces the recirculation and trapping the pollutant downstream near the obstacle. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=CFD" title="CFD">CFD</a>, <a href="https://publications.waset.org/abstracts/search?q=free%20surface" title=" free surface"> free surface</a>, <a href="https://publications.waset.org/abstracts/search?q=polluant%20dispersion" title=" polluant dispersion"> polluant dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=turbulent%20flows" title=" turbulent flows"> turbulent flows</a> </p> <a href="https://publications.waset.org/abstracts/30237/cfd-modeling-of-pollutant-dispersion-in-a-free-surface-flow" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/30237.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">545</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">2433</span> Model of Cosserat Continuum Dispersion in a Half-Space with a Scatterer</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Francisco%20Velez">Francisco Velez</a>, <a href="https://publications.waset.org/abstracts/search?q=Juan%20David%20Gomez"> Juan David Gomez</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Dispersion effects on the Scattering for a semicircular canyon in a micropolar continuum are analyzed, by using a computational finite element scheme. The presence of microrotational waves and the dispersive SV waves affects the propagation of elastic waves. Here, a contrast with the classic model is presented, and the dependence with the micropolar parameters is studied. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=scattering" title="scattering">scattering</a>, <a href="https://publications.waset.org/abstracts/search?q=semicircular%20canyon" title=" semicircular canyon"> semicircular canyon</a>, <a href="https://publications.waset.org/abstracts/search?q=wave%20dispersion" title=" wave dispersion"> wave dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=micropolar%20medium" title=" micropolar medium"> micropolar medium</a>, <a href="https://publications.waset.org/abstracts/search?q=FEM%20modeling" title=" FEM modeling"> FEM modeling</a> </p> <a href="https://publications.waset.org/abstracts/11667/model-of-cosserat-continuum-dispersion-in-a-half-space-with-a-scatterer" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/11667.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">544</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">2432</span> Numerical Solution of Space Fractional Order Solute Transport System</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Shubham%20Jaiswal">Shubham Jaiswal</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In the present article, a drive is taken to compute the solution of spatial fractional order advection-dispersion equation having source/sink term with given initial and boundary conditions. The equation is converted to a system of ordinary differential equations using second-kind shifted Chebyshev polynomials, which have finally been solved using finite difference method. The striking feature of the article is the fast transportation of solute concentration as and when the system approaches fractional order from standard order for specified values of the parameters of the system. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=spatial%20fractional%20order%20advection-dispersion%20equation" title="spatial fractional order advection-dispersion equation">spatial fractional order advection-dispersion equation</a>, <a href="https://publications.waset.org/abstracts/search?q=second-kind%20shifted%20Chebyshev%20polynomial" title=" second-kind shifted Chebyshev polynomial"> second-kind shifted Chebyshev polynomial</a>, <a href="https://publications.waset.org/abstracts/search?q=collocation%20method" title=" collocation method"> collocation method</a>, <a href="https://publications.waset.org/abstracts/search?q=conservative%20system" title=" conservative system"> conservative system</a>, <a href="https://publications.waset.org/abstracts/search?q=non-conservative%20system" title=" non-conservative system"> non-conservative system</a> </p> <a href="https://publications.waset.org/abstracts/80604/numerical-solution-of-space-fractional-order-solute-transport-system" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/80604.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">261</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">2431</span> Pd Supported on Activated Carbon: Effect of Support Texture on the Dispersion of Pd</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ji%20Sun%20Kim">Ji Sun Kim</a>, <a href="https://publications.waset.org/abstracts/search?q=Jae%20Ho%20Baek"> Jae Ho Baek</a>, <a href="https://publications.waset.org/abstracts/search?q=Kyeong%20Ho%20Kim"> Kyeong Ho Kim</a>, <a href="https://publications.waset.org/abstracts/search?q=Ji%20Hae%20Ha"> Ji Hae Ha</a>, <a href="https://publications.waset.org/abstracts/search?q=Seong%20Soo%20Hong"> Seong Soo Hong</a>, <a href="https://publications.waset.org/abstracts/search?q=Jung-Wook%20Park"> Jung-Wook Park</a>, <a href="https://publications.waset.org/abstracts/search?q=Man%20Sig%20Lee"> Man Sig Lee </a> </p> <p class="card-text"><strong>Abstract:</strong></p> Carbon supported palladium catalysts have been used in many industrial reactions, especially for hydrogenation in the fine chemical industry. Porous carbons had been widely used as catalyst supports due to its higher surface area and larger pore volume. The specific surface area, pore structure and surface chemical functional groups of porous carbon affects metal dispersion and particle size. In this paper, we confirm the effect of support texture on the dispersion of Pd. Pd catalyst supported on activated carbon having various specific surface area were characterized by BET, XRD and FE-TEM. Catalyst activity and dispersion of prepared catalyst were evaluated on the basis of the CO adsorption capacity by CO-chemisorption. As concluding remark to this part of our study, let us note that specific area of carbon play important role on the synthesis of Pd/C catalyst/. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=carbon" title="carbon">carbon</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion" title=" dispersion"> dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=Pd%2FC" title=" Pd/C"> Pd/C</a>, <a href="https://publications.waset.org/abstracts/search?q=specific%20are" title=" specific are"> specific are</a>, <a href="https://publications.waset.org/abstracts/search?q=support" title=" support"> support</a> </p> <a href="https://publications.waset.org/abstracts/40084/pd-supported-on-activated-carbon-effect-of-support-texture-on-the-dispersion-of-pd" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/40084.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">352</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">2430</span> Evaluation of the Impact of Green Infrastructure on Dispersion and Deposition of Particulate Matter in Near-Roadway Areas</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Deeksha%20Chauhan">Deeksha Chauhan</a>, <a href="https://publications.waset.org/abstracts/search?q=Kamal%20Jain"> Kamal Jain</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Pollutant concentration is high in near-road environments, and vegetation is an effective measure to mitigate urban air quality problems. This paper presents the influence of roadside green infrastructure in dispersion and Deposition of Particulate matter (PM) by the ENVI-met Simulations. Six green infrastructure configurations were specified (i) hedges only, (ii) trees only, (iii) a mix of trees and shrubs (iv) green barrier (v) green wall, and (vi) no tree buffer were placed on both sides of the road. The changes in concentrations at all six scenarios were estimated to identify the best barrier to reduce the dispersion and deposition of PM10 and PM2.5 in an urban environment. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=barrier" title="barrier">barrier</a>, <a href="https://publications.waset.org/abstracts/search?q=concentration" title=" concentration"> concentration</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion" title=" dispersion"> dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=deposition" title=" deposition"> deposition</a>, <a href="https://publications.waset.org/abstracts/search?q=Particulate%20matter" title=" Particulate matter"> Particulate matter</a>, <a href="https://publications.waset.org/abstracts/search?q=pollutant" title=" pollutant"> pollutant</a> </p> <a href="https://publications.waset.org/abstracts/127902/evaluation-of-the-impact-of-green-infrastructure-on-dispersion-and-deposition-of-particulate-matter-in-near-roadway-areas" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/127902.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">145</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">2429</span> Numerical Study of Blackness Factor Effect on Dark Solitons</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Khelil%20Khadidja">Khelil Khadidja</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this paper, blackness of dark solitons is considered. The exact combination between nonlinearity and dispersion is responsible of solitons stability. Dark solitons get born when dispersion is abnormal and balanced by nonlinearity, at the opposite of brillant solitons which is born by normal dispersion and nonlinearity together. Thanks to their stability, dark solitons are suitable for transmission by optical fibers. Dark solitons which are a solution of Nonlinear Schrodinger equation are simulated with Matlab to discuss the influence of coefficient of blackness. Results show that there is a direct proportion between the coefficient of blackness and the intensity of dark soliton. Those gray solitons are stable and convenient for transmission. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=abnormal%20dispersion" title="abnormal dispersion">abnormal dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=nonlinearity" title=" nonlinearity"> nonlinearity</a>, <a href="https://publications.waset.org/abstracts/search?q=optical%20fiber" title=" optical fiber"> optical fiber</a>, <a href="https://publications.waset.org/abstracts/search?q=soliton" title=" soliton"> soliton</a> </p> <a href="https://publications.waset.org/abstracts/80445/numerical-study-of-blackness-factor-effect-on-dark-solitons" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/80445.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">198</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">2428</span> Quantification of Dispersion Effects in Arterial Spin Labelling Perfusion MRI</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Rutej%20R.%20Mehta">Rutej R. Mehta</a>, <a href="https://publications.waset.org/abstracts/search?q=Michael%20A.%20Chappell"> Michael A. Chappell</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Introduction: Arterial spin labelling (ASL) is an increasingly popular perfusion MRI technique, in which arterial blood water is magnetically labelled in the neck before flowing into the brain, providing a non-invasive measure of cerebral blood flow (CBF). The accuracy of ASL CBF measurements, however, is hampered by dispersion effects; the distortion of the ASL labelled bolus during its transit through the vasculature. In spite of this, the current recommended implementation of ASL – the white paper (Alsop et al., MRM, 73.1 (2015): 102-116) – does not account for dispersion, which leads to the introduction of errors in CBF. Given that the transport time from the labelling region to the tissue – the arterial transit time (ATT) – depends on the region of the brain and the condition of the patient, it is likely that these errors will also vary with the ATT. In this study, various dispersion models are assessed in comparison with the white paper (WP) formula for CBF quantification, enabling the errors introduced by the WP to be quantified. Additionally, this study examines the relationship between the errors associated with the WP and the ATT – and how this is influenced by dispersion. Methods: Data were simulated using the standard model for pseudo-continuous ASL, along with various dispersion models, and then quantified using the formula in the WP. The ATT was varied from 0.5s-1.3s, and the errors associated with noise artefacts were computed in order to define the concept of significant error. The instantaneous slope of the error was also computed as an indicator of the sensitivity of the error with fluctuations in ATT. Finally, a regression analysis was performed to obtain the mean error against ATT. Results: An error of 20.9% was found to be comparable to that introduced by typical measurement noise. The WP formula was shown to introduce errors exceeding 20.9% for ATTs beyond 1.25s even when dispersion effects were ignored. Using a Gaussian dispersion model, a mean error of 16% was introduced by using the WP, and a dispersion threshold of σ=0.6 was determined, beyond which the error was found to increase considerably with ATT. The mean error ranged from 44.5% to 73.5% when other physiologically plausible dispersion models were implemented, and the instantaneous slope varied from 35 to 75 as dispersion levels were varied. Conclusion: It has been shown that the WP quantification formula holds only within an ATT window of 0.5 to 1.25s, and that this window gets narrower as dispersion occurs. Provided that the dispersion levels fall below the threshold evaluated in this study, however, the WP can measure CBF with reasonable accuracy if dispersion is correctly modelled by the Gaussian model. However, substantial errors were observed with other common models for dispersion with dispersion levels similar to those that have been observed in literature. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=arterial%20spin%20labelling" title="arterial spin labelling">arterial spin labelling</a>, <a href="https://publications.waset.org/abstracts/search?q=dispersion" title=" dispersion"> dispersion</a>, <a href="https://publications.waset.org/abstracts/search?q=MRI" title=" MRI"> MRI</a>, <a href="https://publications.waset.org/abstracts/search?q=perfusion" title=" perfusion"> perfusion</a> </p> <a href="https://publications.waset.org/abstracts/29742/quantification-of-dispersion-effects-in-arterial-spin-labelling-perfusion-mri" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/29742.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">371</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=dispersion%20equations&page=2">2</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=dispersion%20equations&page=3">3</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=dispersion%20equations&page=4">4</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=dispersion%20equations&page=5">5</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=dispersion%20equations&page=6">6</a></li> <li class="page-item"><a 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