Дисертації з теми "Unstructured meshe"
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Dapogny, Charles. "Shape optimization, level set methods on unstructured meshes and mesh evolution." Paris 6, 2013. http://www.theses.fr/2013PA066498.
Повний текст джерелаThe main purpose of this thesis is to propose a method for structural optimization which combines theaccuracy of featuring an exact description of shapes (i. E. With a mesh) at each iteration of the process withthe versatility of the level set method for tracking their evolution. Independently, we also study two problemsrelated to modeling in structural optimization. In the first, bibliographical part, we present several classical notions, together with some recent developmentsabout the three main issues of this thesis - namely level set methods (Chapter 1), shape optimization(Chapter 2), and meshing (Chapter 3). The second part of this manuscript deals with two issues in shape optimization, that of the optimalrepartition of several materials within a fixed structure (Chapter 4), and that of the robust optimization offunctions depending on the domain when perturbations are expected over the considered mechanical model. In the third part, we study the design of numerical schemes for performing the level set method onsimplicial (and possibly adapted) computational meshes. The computation of the signed distance functionto a domain is investigated in Chapter 6, and the resolution of the level set advection equation is presentedin Chapter 7. The fourth part (Chapter 8) is devoted to the meshing techniques introduced in this thesis. Eventually, the last part (Chapter 9) describes the proposed strategy for mesh evolution in the contextof shape optimization, relying on the numerical ingredients introduced in Chapters 7, 8, 9
Hindenlang, Florian [Verfasser]. "Mesh Curving Techniques for High Order Parallel Simulations on Unstructured Meshes / Florian Hindenlang." München : Verlag Dr. Hut, 2014. http://d-nb.info/1060587653/34.
Повний текст джерелаHarbrecht, Helmut, Ulf Kähler, and Reinhold Schneider. "Wavelet Galerkin BEM on unstructured meshes." Universitätsbibliothek Chemnitz, 2006. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200601459.
Повний текст джерелаROCHA, ALLAN CARLOS AVELINO. "ILLUSTRATIVE VOLUME VISUALIZATION FOR UNSTRUCTURED MESHES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2011. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18748@1.
Повний текст джерелаTécnicas de visualização científica criam imagens na tentativa de revelar estruturas e fenômenos complexos. Técnicas ilustrativas têm sido incorporadas aos sistemas de visualizacão científica para melhorar a expressividade de tais imagens. A visualização de linhas caracteríticas é uma técnica importante para transmitir uma melhor informacão sobre a forma das superfícies. Neste trabalho, propomos combinar visualização volumétrica de malhas não estruturadas com isosuperfícies ilustradas. Isto é feito estendendo um algoritmo de traçado de raio em GPU para incorporar ilustração com linhas de variação extrema da iluminação(photic extremum lines), um tipo de linha característica que captura mudanças bruscas de luminância, revelando formas de um jeito perceptualmente correto.
Scientic visualization techniques create images attempting to reveal complex structures and phenomena. Illustrative techniques have been incorporated to scientic visualization systems in order to improve the expressiveness of such images. The rendering of feature lines is an important technique for better depicting surface shapes and features. In this thesis, we propose to combine volume visualization of unstructured meshes with illustrative isosurfaces. This is accomplished by extending a GPU-based ray-casting algorithm to incorporate illustration with photic extremum lines, a type of feature lines able to capture sudden changes of luminance, conveying shapes in a perceptually correct way.
MIRANDA, FABIO MARKUS NUNES. "VOLUME RENDERING OF UNSTRUCTURED HEXAHEDRAL MESHES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2011. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=28921@1.
Повний текст джерелаCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
Importantes aplicações de engenharia usam malhas não estruturadas de hexaedros para simulações numéricas. Células hexaédricas, comparadas com tetraedros, tendem a ser mais numericamente estáveis e requerem um menor refinamento da malha. Entretando, visualização volumétrica de malhas não estruturadas é um desafio devido a variação trilinear do campo escalar dentro da célula. A solução convencional consiste em subdividir cada hexaedro em cinco ou seis tetraedros, aproximando uma variação trilinear por uma inadequada série de funções lineares. Isso resulta em imagens inadequadas e aumenta o consumo de memória. Nesta tese, apresentamos um algoritmo preciso de visualização volumétrica utilizando ray-casting para malhas não estruturadas de hexaedros. Para capturar a variação trilinear ao longo do raio, nós propomos usar uma integração de quadratura. Nós também propomos uma alternativa rápida que melhor aproxima a variação trilinear, considerando os pontos de mínimo e máximo da função escalar ao longo do raio. Uma série de experimentos computacionais demonstram que nossa proposta produz resultados exatos, com um menor gasto de memória. Todo algoritmo é implementado em placas gráficas, garantindo uma performance competitiva.
Important engineering applications use unstructured hexahedral meshes for numerical simulations. Hexahedral cells, when compared to tetrahedral ones, tend to be more numerically stable and to require less mesh refinement. However, volume visualization of unstructured hexahedral meshes is challenging due to the trilinear variation of scalar fields inside the cells. The conventional solution consists in subdividing each hexahedral cell into five or six tetrahedra, approximating a trilinear variation by an inadequate piecewise linear function. This results in inaccurate images and increases the memory consumption. In this thesis, we present an accurate ray-casting volume rendering algorithm for unstructured hexahedral meshes. In order to capture the trilinear variation along the ray, we propose the use of quadrature integration. We also propose a fast approach that better approximates the trilinear variation to a series of linear ones, considering the points of minimum and maximum of the scalar function along the ray. A set of computational experiments demonstrates that our proposal produces accurate results, with reduced memory footprint. The entire algorithm is implemented on graphics cards, ensuring competitive performance.
Burgess, David A. "Parallel computing for unstructured mesh algorithms." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318758.
Повний текст джерелаPerez, Sansalvador Julio. "Parallel unstructured mesh adaptation and applications." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/parallel-unstructured-mesh-adaptation-and-applications(26248d4d-48a6-4101-a687-004218e39cb4).html.
Повний текст джерелаHindenlang, Florian [Verfasser], and Claus-Dieter [Akademischer Betreuer] Munz. "Mesh curving techniques for high order parallel simulations on unstructured meshes / Florian Hindenlang. Betreuer: Claus-Dieter Munz." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2014. http://d-nb.info/1063938082/34.
Повний текст джерелаBushrod, Rebecca. "Unstructured mesh generation for mesh improvement techniques and contour meshing." Thesis, Swansea University, 2005. https://cronfa.swan.ac.uk/Record/cronfa42434.
Повний текст джерелаKumar, Amitesh. "Hole patching in 3D unstructured surface mesh." Birmingham, Ala. : University of Alabama at Birmingham, 2007. http://www.mhsl.uab.edu/dt/2007m/kumar.pdf.
Повний текст джерелаBunt, Richard A. "Performance engineering unstructured mesh, geometric multigrid codes." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/89503/.
Повний текст джерелаZhang, Zhao. "Unstructured mesh methods for stratified turbulent flows." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/16617.
Повний текст джерелаHong, Sung Min. "Shape Modeling of Plant Leaves with Unstructured Meshes." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/1182.
Повний текст джерелаFRANCESCHIN, BERNARDO BIANCHI. "VISUALIZATION OF ARBITRARY CROSS SECTION OF UNSTRUCTURED MESHES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2013. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=23874@1.
Повний текст джерелаCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
PROGRAMA DE EXCELENCIA ACADEMICA
Na visualização de campos escalares de dados volumétricos, o uso de seções de corte é uma técnica eficaz para se inspecionar a variação do campo no interior do domínio. A técnica de visualização consiste em mapear sobre a superfície da seção de corte um mapa de cores, o qual representa a variação do campo escalar na interseção da superfície com o volume. Este trabalho propõe um método eficiente para o mapeamento de campos escalares de malhas não estruturadas em seções de corte arbitrárias. Trata-se de um método de renderização direta (a interseção da superfície com o modelo não é extraída) que usa a GPU para garantir bom desempenho. A idéia básica do método proposto é utilizar o rasterizador da placa gráfica para gerar os fragmentos da superfície de corte e calcular a interseção de cada fragmento com o modelo em GPU. Para isso, é necessário testar a localização de cada fragmento na malha não estruturada de maneira eficiente. Como estrutura de aceleração, foram testadas três variações de grades regulares para armazenar os elementos (células) da malha, e cada elemento é representado pela lista de planos de suas faces, facilitando o teste de pertinência fragmento-elemento. Uma vez determinado o elemento que contém o fragmento, são aplicados procedimentos para interpolar o campo escalar e para identificar se o fragmento está próximo à fronteira do elemento, a fim de representar o aramado (wireframe) da malha na superfície de corte. Resultados obtidos demonstram a eficácia e a eficiência do método proposto.
For the visualization of scalar fields in volume data, the use of cross sections is an effective technique to inspect the field variation inside the domain. The technique consists in mapping, on the cross section surfaces, a colormap that represents the scalar field on the surfasse-volume intersection. In this work, we propose an efficient method for mapping scalar fields of unstructured meshes on arbitrary cross sections. It is a direct-rendering method (the intersection of the surface and the model is not extracted) that uses GPU to ensure efficiency. The basic idea is to use the graphics rasterizer to generate the fragments of the cross-section surface and to compute the intersection of each fragment with the model. For this, it is necessary to test the location of each fragment with respect to the unstructured mesh in an efficient way. As acceleration data structure, we tested three variations of regular grids to store the elements (cells) of the mesh, and each elemento is represented by the list of face planes, easing the in-out test between fragments and elements. Once the element that contains the fragment is determined, it is applied procedures to interpolate the scalar field and to check if the fragment is close to the element boundary, to reveal the mesh wireframe on the surface. Achieved results demonstrate the effectiveness and the efficiency of the proposed method.
Davey, Robert A. "Decomposition of unstructured meshes for efficient parallel computation." Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/13572.
Повний текст джерелаWilson, Cian. "Modelling multiple-material flows on adaptive unstructured meshes." Thesis, Imperial College London, 2009. http://hdl.handle.net/10044/1/5526.
Повний текст джерелаGorman, Gerard John. "Parallel anisotropic unstructured mesh optimisation and its applications." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430146.
Повний текст джерелаManickam, Pradeep. "Unstructured mesh based models for incompressible turbulent flows." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/14126.
Повний текст джерелаBouvattier, Marc-Antoine. "Unstructured mesh adaptation for turbo-machinery RANS computation." Thesis, KTH, Flygdynamik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211161.
Повний текст джерелаSharbatdar, Mahkame. "Error estimation and mesh adaptation paradigm for unstructured mesh finite volume methods." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/60359.
Повний текст джерелаApplied Science, Faculty of
Mechanical Engineering, Department of
Graduate
Jofre, Cruanyes Lluís. "Numerical simulation of multiphase immiscible flow on unstructured meshes." Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/277545.
Повний текст джерелаAquesta tesi té com a objectiu desenvolupar una base per a la simulació numèrica de fluids multi-fase immiscibles. Aquesta estratègia, encara que limitada per la potència computacional dels computadors actuals, és potencialment molt important, ja que la majoria de la fenomenologia d'aquests fluids sovint passa en escales temporals i especials on les tècniques experimentals no poden ser utilitzades. En particular, aquest treball es centra en desenvolupar discretitzacions numèriques aptes per a malles no-estructurades en tres dimensions (3-D). En detall, el primer capítol delimita els casos multifásics considerats al cas en que els components són fluids immiscibles. En particular, la tesi es centra en aquells casos en que dos o més fluids diferents són separats per interfases, i per tant, corresponentment anomenats fluxos separats. A més a més, un cop el tipus de flux es determinat, el capítol introdueix les característiques físiques i els models disponibles per predir el seu comportament, així com també la formulació matemàtica i les tècniques numèriques desenvolupades en aquesta tesi. El segon capítol introdueix i analitza un nou mètode "Volume-of-Fluid" (VOF) apte per a capturar interfases en malles Cartesianes i no-estructurades 3-D. El mètode reconstrueix les interfases com aproximacions "piecewise planar approximations" (PLIC) de primer i segon ordre, i advecciona els volums amb un algoritme geomètric "unsplit Lagrangian-Eulerian" (LE) basat en construïr els poliedres a partir de les velocitats dels vèrtexs de les celdes. D'aquesta manera, les situacions de sobre-solapament entre poliedres són minimitzades. Complementant el capítol anterior, el tercer proposa una estratègia de paral·lelització pel mètode VOF. L'obstacle principal és que els costos computacionals estan concentrats en les celdes de l'interfase entre fluids. En conseqüència, si la interfase no està ben distribuïda, les estratègies de "domain decomposition" (DD) resulten en distribucions de càrrega desequilibrades. Per tant, la nova estratègia està basada en un procés de balanceig de càrrega complementària a la DD. La seva eficiència en paral·lel ha sigut analitzada utilitzant fins a 1024 CPU-cores, i els resultats obtinguts mostren uns guanys respecte l'estratègia DD de fins a 12x, depenent del tamany de la interfase i de la distribució inicial. El quart capítol descriu la discretització de les equacions de Navier-Stokes per a una sola fase, per després estendre-ho al cas multi-fase. Una de les característiques més importants dels esquemes de discretització, a part de la precisió, és la seva capacitat per conservar discretament l'energia cinètica, específicament en el cas de fluxos turbulents. Per tant, aquest capítol analitza la precisió i propietats de conservació de dos esquemes de malla diferents: "collocated" i "staggered". L'extensió dels esquemes de malla aptes per els casos de una sola fase als casos multi-fase es desenvolupa en el cinquè capítol. En particular, així com en el cas de la simulació de la turbulència les tècniques numèriques han evolucionat per a preservar discretament massa, moment i energia cinètica, els esquemes de malla per a la discretització de fluxos multi-fase han evolucionat per millorar la seva estabilitat i robustesa. Per lo tant, aquest capítol presenta i analitza dos discretitzacions de malla "collocated" i "staggered" particulars, aptes per simular fluxos multi-fase, que afavoreixen la conservació discreta de massa, moment i energia cinètica. Finalment, el capítol sis simula numèricament la inestabilitat de Richtmyer-Meshkov (RM) de dos fluids immiscibles i incompressibles. Aquest capítol es una prova general dels mètodes numèrics desenvolupats al llarg de la tesi. En particular, la inestabilitat ha sigut simulada mitjançant un mètode VOF i un esquema de malla "staggered". Els resultats numèrics corresponents han demostrat la capacitat del sistema discret en obtenir bons resultats per la inestabilitat RM.
Vilmin, Stéphane. "Turbulence modeling on unstructured meshes for 3D turbomachinery CFD /." Lausanne : EPFL, 1998. http://library.epfl.ch/theses/?nr=1864.
Повний текст джерелаBorrell, Pol Ricard. "Parallel algorithms for computational fluid dynamics on unstructured meshes." Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/124702.
Повний текст джерелаDirect Numerical Simulation (DNS) of complex flows is currently an utopia for most of industrial applications because computational requirements are too high. For a given flow, the gap between the required and the available computing resources is covered by modeling/simplifying of some terms of the original equations. On the other hand, the continuous growth of the computing power of modern supercomputers contributes to reduce this gap, reducing hence the unresolved physics that need to be attempted with approximated models. This growth, widely relies on parallel computing technologies. However, getting the expected performance from new complex computing systems is becoming more and more difficult, and therefore part of the CFD research is focused on this goal. Regarding to it, some contributions are presented in this thesis. The first objective was to contribute to the development of a general purpose multi-physics CFD code. referred to as TermoFluids (TF). TF is programmed following the object oriented paradigm and designed to run in modern parallel computing systems. It is also intensively involved in many different projects ranging from basic research to industry applications. Besides, one of the strengths of TF is its good parallel performance demonstrated in several supercomputers. In the context of this thesis, the work was focused on the development of two of the most basic libraries that compose TF: I) the Basic Objects Library (BOL), which is a parallel unstructured CFD application programming interface, on the top of which the rest of libraries that compose TF are written, ii) the Linear Solvers Library (LSL) containing many different algorithms to solve the linear systems arising from the discretization of the equations. The first chapter of this thesis contains the main ideas underlying the design and the implementation of the BOL and LSL libraries, together with some examples and some industrial applications. A detailed description of some application-specific linear solvers included in the LSL is carried out in the following chapters. In the second chapter, a parallel direct Poisson solver restricted to problems with one uniform periodic direction is presented. The Poisson equation is solved, at least, once per time-step when modeling incompressible flows, becoming one of the most time consuming and difficult to parallelize parts of the code. The solver here proposed is a combination of a direct Schur-complement based decomposition (DSD) and a Fourier diagonalization. The latter decomposes the original system into a set of mutually independent 2D sub-systems which are solved by means of the DSD algorithm. Since no restrictions are imposed in the non-periodic directions, the overall algorithm is well-suited for solving problems discretized on extruded 2D unstructured meshes. The scalability of the solver has been successfully tested using up to 8192 CPU cores for meshes with up to 10 9 grid points. In the last chapter, a solver for the Boltzmann Transport Equation (BTE) is presented. It can be used to solve radiation phenomena interacting with flows. The solver is based on the Discrete Ordinates Method and can be applied to unstructured discretizations. The flux for each angular ordinate is swept across the computational grid, within a source iteration loop that accounts for the coupling between the different ordinates. The sequential nature of the sweep process makes the parallelization of the overall algorithm the most challenging aspect. Several parallel sweep algorithms, which represent different options of interleaving communications and calculations, are analyzed. One of the heuristics proposed consistently stands out as the best option in all the situations analyzed. With this algorithm, good scalability results have been achieved regarding both weak and strong speedup tests with up to 2560 CPUs.
De, la Puente Josep. "Seismic Wave Simulation for Complex Rheologies on Unstructured Meshes." Diss., lmu, 2008. http://nbn-resolving.de/urn:nbn:de:bvb:19-80745.
Повний текст джерелаTheodoropoulos, Theodoros. "Prediction of three-dimensional engine flow on unstructured meshes." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46575.
Повний текст джерелаDawkins, Ian. "Development of practical evolution Galerkin algorithms on unstructured meshes." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390460.
Повний текст джерелаWillcox, Karen E. (Karen Elizabeth). "Aeroelastic computations in the time domain using unstructured meshes." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/11185.
Повний текст джерелаShala, Mehmet. "Unstructured staggered mesh discretisation methods for computational fluid dynamics." Thesis, University of Greenwich, 2007. http://gala.gre.ac.uk/6297/.
Повний текст джерелаJones, Beryl Wyn. "Mapping unstructured mesh codes onto local memory parallel architectures." Thesis, University of Greenwich, 1994. http://gala.gre.ac.uk/6201/.
Повний текст джерелаSmith, Cameron Walter. "Improving Scalability of Parallel Unstructured Mesh-Based Adaptive Workflows." Thesis, Rensselaer Polytechnic Institute, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10269567.
Повний текст джерелаHigh performance parallel adaptive simulations operating on leadership class systems are constructed from multiple pieces of software developed over many years. As increasingly complex systems are deployed new methods must be created to extract performance and scalability. This thesis addresses two key scalability limitations for unstructured mesh based simulations.
Attaining simulation performance at ever higher concurrency levels requires increased performance of transformations within each procedure, as well as the transfer of data between procedures.
Controlling the transformations requires distributing the work evenly across the processors while executing efficient data transfers requires local operations that avoid shared or contended resources. This thesis addresses these requirements through multi-criteria load balancing procedures and in-memory data transfer techniques.
Partition improvement methods defined in this work enable improved application strong scaling on over one million processors through careful control of the balancing requirements. Applied to a computational fluid dynamics simulation running on 524,288 processes with 1.2 billion elements these methods reduce the time of the dominant computational step by up to 28% versus the best existing methods.
The scalable data transfer requirement is addressed through an in-memory functional coupling that avoids the high cost of fileystem access. The methods developed are applied to two adaptive simulations in which the time required for information exchange is reduced by over an order of magnitude versus file based couplings. Three additional simulations for industrial applications are then provided that highlight an in-memory coupling and the automation of key simulation processes.
Oyarzún, Altamirano Guillermo Andrés. "Heterogeneous parallel algorithms for computational fluid dynamics on unstructured meshes." Doctoral thesis, Universitat Politècnica de Catalunya, 2015. http://hdl.handle.net/10803/323892.
Повний текст джерелаLas fronteras de la dinámica de fluidos computacional (CFD) están en constante expansión y demandan más y más recursos computacionales. Actualmente, estamos experimentando una evolución en los sistemas de computación de alto rendimiento (HPC) impulsado por restricciones de consumo de energía. Los nuevos nodos HPC incorporan aceleradores que se utilizan como co-procesadores para incrementar el rendimiento y la relación FLOP por vatio. Por otro lado, CPUs multi-core se han convertido en arquitecturas system-on-chip. Hoy en día, varias instituciones y gobiernos están invirtiendo en la investigación y desarrollo de los diferentes aspectos de HPC que podrían llevar a las próximas generaciones de superordenadores. Estas iniciativas han titulado el problema como el "exascale challenge". Este objetivo sólo puede lograrse mediante la incorporación de cambios importantes en: la arquitectura de ordenador, diseño de la memoria y las interfaces de red. La comunidad de CFD se enfrenta a un reto importante: mantener el ritmo a los rápidos cambios en las infraestructuras de HPC. Los códigos y formulaciones necesitan ser rediseñados para explotar los diferentes niveles de paralelismo y complejas jerarquías de memoria de los nuevos sistemas heterogéneos. Las principales características exigidas al nuevo software CFD son: estructuras de datos, la concurrencia extrema, modularidad y portabilidad. Esta tesis está dedicada al estudio de un modelo de implementation CFD para la adopción de nuevas tecnologías. Nuestro contexto de aplicación es la solución de los flujos incompresibles (DNS o LES) en mallas no estructuradas. El primer enfoque se basó en utilizar GPUs para acelerar el solver de Poisson. Los resultados positivos obtenidos en este primer paso nos motivaron a la portabilidad completa de la fase de integración temporal de nuestra aplicación. Esto requiere un importante rediseño del código. Proponemos un modelo de implementacion portable para aplicaciones de CFD. La idea principal es sustituir las estructuras de datos de los stencils y kernels por formatos de almacenamiento algebraicos y operadores. La estrategia de implementación consistió en la creación de una capa algebraica de bajo nivel para los cálculos de CPU y GPU, y una capa de discretización fácil de usar de alto nivel para las CPU. Como resultado, la fase de integración temporal del código se basa sólo en tres funciones algebraicas: producto de una matriz dispersa con un vector (SPMV), combinación lineal de dos vectores (AXPY) y producto escalar (DOT). Además, se prestó especial atención en el desarrollo de estructuras de datos compatibles con el modelo stream processing. Un análisis detallado de rendimiento se ha estudiado tanto en ejecución secuencial y paralela utilizando hasta 128 GPUs en un superordenador híbrido CPU / GPU. Por otra parte, hemos probado el nuevo modelo de TermoFluids en el superordenador Mont-Blanc basado en tecnología móvil. El rediseño de las funciones explota un modelo de ejecución heterogénea utilizando tanto la CPU y la GPU de los nodos basados en arquitectura ARM. El equilibrio de carga entre las dos unidades de cálculo aprovecha una estrategia de búsqueda tabú que sintoniza la distribución de carga de trabajo durante la etapa de preprocesamiento. Una comparación de los prototipos Mont-Blanc con superordenadores de alta gama en términos de rendimiento y consumo de energía nos proporcionó algunas pautas del comportamiento de las aplicaciones CFD en arquitecturas basadas en ARM. Por último, se presenta una estructura de datos auto-sintonizada para el solver de Poisson en problemas con una dirección diagonalizable mediante una descomposicion de Fourier. Este trabajo fue desarrollado y probado en la superordenador BlueGene / Q Vesta, y tiene por objeto demostrar la relevancia de vectorización y las estructuras de datos para aprovechar plenamente las CPUs de los superodenadores modernos.
Simmons, Daniel. "Hybrid methods for modelling advanced electromagnetic systems using unstructured meshes." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33230/.
Повний текст джерелаAsproulis, Panagiotis. "High resolution numerical predictions of hypersonic flows on unstructured meshes." Thesis, Imperial College London, 1994. http://hdl.handle.net/10044/1/8357.
Повний текст джерелаRahmati, M. T. "Incompressible Navier-Stokes inverse design method based on unstructured meshes." Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1445805/.
Повний текст джерелаIssman, Emmanuel. "Implicit solution strategies for compressible flow equations on unstructured meshes." Doctoral thesis, Universite Libre de Bruxelles, 1997. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212181.
Повний текст джерелаESPINHA, RODRIGO DE SOUZA LIMA. "INTERACTIVE VOLUME VISUALIZATION OF UNSTRUCTURED MESHES USING PROGRAMMABLE GRAPHICS CARDS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=6586@1.
Повний текст джерелаA visualização volumétrica é uma importante técnica para a exploração de dados tridimensionais complexos, como, por exemplo, o resultado de análises numéricas usando o método dos elementos finitos. A aplicação eficiente dessa técnica a malhas não-estruturadas tem sido uma importante área de pesquisa nos últimos anos. Há dois métodos básicos para a visualização dos dados volumétricos: extração de superfícies e renderização direta de volumes. Na primeira, iso-superfícies de um campo escalar são extraídas explicitamente. Na segunda, que é a utilizada neste trabalho, dados escalares são classificados a partir de uma função de transferência, que mapeia valores do campo escalar em cor e opacidade, para serem visualizados. Com a evolução das placas gráficas (GPU) dos computadores pessoais, foram desenvolvidas novas técnicas para visualização volumétrica interativa de malhas não-estruturadas. Os novos algoritmos tiram proveito da aceleração e da possibilidade de programação dessas placas, cujo poder de processamento cresce a um ritmo superior ao dos processadores convencionais (CPU). Este trabalho avalia e compara dois algoritmos para visualização volumétrica de malhas não-estruturadas, baseados em GPU: projeção de células independente do observador e traçado de raios. Adicionalmente, são propostas duas adaptações dos algoritmos estudados. Para o algoritmo de projeção de células, propõe-se uma estruturação dos dados na GPU para eliminar o alto custo de transferência de dados para a placa gráfica. Para o algoritmo de traçado de raios, propõe-se fazer a integração da função de transferência na GPU, melhorando a qualidade da imagem final obtida e permitindo a alteração da função de transferência de maneira interativa.
Volume visualization is an important technique for the exploration of threedimensional complex data sets, such as the results of numerical analysis using the finite elements method. The efficient application of this technique to unstructured meshes has been an important area of research in the past few years. There are two basic methods to visualize volumetric data: surface extraction and direct volume rendering. In the first, the iso-surfaces of the scalar field are explicitly extracted. In the second, which is the one used in this work, scalar data are classified by a transfer function, which maps the scalar values to color and opacity, to be visualized. With the evolution of personal computer graphics cards (GPU), new techniques for volume visualization have been developed. The new algorithms take advantage of modern programmable graphics cards, whose processing power increases at a faster rate than the one observed in conventional processors (CPU). This work evaluates and compares two GPU- based algorithms for volume visualization of unstructured meshes: view- independent cell projection (VICP) and ray-tracing. In addition, two adaptations of the studied algorithms are proposed. For the cell projection algorithm, we propose a GPU data structure in order to eliminate the high costs of the CPU to GPU data transfer. For the raytracing algorithm, we propose to integrate the transfer function in the GPU, which increases the quality of the generated image and allows to interactively change the transfer function.
Kaus, Cynthia Christine 1965. "Topological and geometrical considerations for Maxwell's equations on unstructured meshes." Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/282472.
Повний текст джерелаCharlesworth, David John. "Solution of the incompressible Navier-Stokes equations on unstructured meshes." Thesis, University College London (University of London), 2004. http://discovery.ucl.ac.uk/1446891/.
Повний текст джерелаParrish, Michael H. "A selective approach to conformal refinement of unstructured hexahedral meshes /." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd1985.pdf.
Повний текст джерелаParrish, Michael Hubbard. "A Selective Approach to Hexahedral Refinement of Unstructured Conformal Meshes." BYU ScholarsArchive, 2007. https://scholarsarchive.byu.edu/etd/979.
Повний текст джерелаCroft, Thomas Nicholas. "Unstructured mesh : finite volume algorithms for swirling, turbulent, reacting flows." Thesis, University of Greenwich, 1998. http://gala.gre.ac.uk/6371/.
Повний текст джерелаBirger, Christopher. "Optimal Coherent Reconstruction of Unstructured Mesh Sequences with Evolving Topology." Thesis, Linköpings universitet, Medie- och Informationsteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-112095.
Повний текст джерелаOkusanya, Tolulope Olawale 1972. "An algorithm for parallel unstructured mesh generation and flow analysis." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/46452.
Повний текст джерелаMcDonald, Cameron L. "Automatic, Unstructured Mesh Generation for 2D Shelf Based Tidal Models." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1550.pdf.
Повний текст джерелаChow, Peter M. Y. "Control volume unstructured mesh procedure for convection-diffusion solidification processes." Thesis, University of Greenwich, 1993. http://gala.gre.ac.uk/6133/.
Повний текст джерелаGargallo, Peiró Abel. "Validation and generation of curved meshes for high-order unstructured methods." Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/275977.
Повний текст джерелаAntoniadis, Antonios Foivos. "High-order methods on mixed-element unstructured meshes for aeronautical applications." Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/7891.
Повний текст джерелаKieri, Emil. "Accuracy aspects of the reaction-diffusion master equation on unstructured meshes." Thesis, Uppsala universitet, Avdelningen för teknisk databehandling, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-145978.
Повний текст джерелаLi, Yenjung. "Compressible Navier-Stokes computations for two-dimensional geometries using unstructured meshes." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339144.
Повний текст джерелаDenner, Fabian. "Balanced-force two-phase flow modelling on unstructured and adaptive meshes." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/28101.
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