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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
311

FÍSICA APLICADA NAS SITUAÇÕES DE TRÂNSITO

Brust, Alexandre 19 December 2013 (has links)
Made available in DSpace on 2018-06-27T19:12:54Z (GMT). No. of bitstreams: 3 Alexandre Brust.pdf.txt: 107472 bytes, checksum: 05646f4de5ee44912e3b75e7da90fcc7 (MD5) Alexandre Brust.pdf.jpg: 3286 bytes, checksum: 3e86301426c3f6b8d1c39f754aaf7457 (MD5) Alexandre Brust.pdf: 2660130 bytes, checksum: 291968ae6c224dcce166603b07f4e114 (MD5) Previous issue date: 2013-12-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aimed to evaluate the role of education in traffic associated with kinematics and evaluate possible changes in behavior with respect to the direction of future drivers. Participated in our survey, students in the first year of high school, a private educational institution in the North West of the State of Rio Grande do Sul. In all activities was used traffic to assist in the understanding of some physical concepts in kinematics and the Newton´s laws, physics curriculum content for the first year. The survey was conducted using structured questionnaires along with application classes using the methodology of the three pedagogical moments methodology for providing discussion between students and teacher and for problem-solving. Besides the three questionnaires during classes, some observations were made in the development of activities. The traffic topic is very useful for the application of physics concepts, providing a major increase in the appropriation of knowledge by the students (meaningful learning), in relation to these concepts. We conclude that this work contributed to the construction of knowledge of the physics of the participants. A significant change in attitude toward transit was also observed by changing thoughts and even forming opinions not previously existed. / O presente trabalho teve como objetivo avaliar o papel da educação no trânsito associada a aula de cinemática e avaliar possíveis mudanças de comportamento com relação a direção de futuros motoristas. Participaram de nossa pesquisa, alunos do primeiro ano do Ensino Médio, de uma Instituição de Ensino Privado no Noroeste do Estado do Rio Grande do Sul. Em todas as atividades foi utilizado tema Trânsito para auxiliar na compreensão de alguns conceitos físicos presentes na Cinemática e nas Leis de Newton, conteúdos do currículo da Física para o primeiro ano. A pesquisa foi realizada utilizando questionários estruturados, juntamente com aulas de aplicação com o uso da metodologia dos três momentos pedagógicos, metodologia utilizada por proporcionar discussão entre os alunos e o professor e por ter caráter problematizador. Além dos três questionários aplicados no decorrer das aulas, foram feitas algumas observações no desenvolvimento das atividades. O tema Trânsito é muito útil para a aplicação de conceitos de Física, proporcionando um acréscimo na apropriação do conhecimento por parte dos alunos (aprendizagem significativa), em relação à esses conceitos. Concluímos que esse trabalho contribuiu para a construção do conhecimento da Física dos participantes. Também foi observada uma mudança significativa de atitude em relação ao trânsito, alterando pensamentos e até mesmo formando opiniões que anteriormente nem existiam.
312

Fluxo de potencia otimo parametrico

Lima, Flavio Guilherme de Melo 07 July 2000 (has links)
Orientadores: Secundino Soares Filho, Anesio dos Santos Jr / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-07-27T03:45:06Z (GMT). No. of bitstreams: 1 Lima_FlavioGuilhermedeMelo_D.pdf: 4842117 bytes, checksum: c30c5445d55e6b97e6857d86e7a136ff (MD5) Previous issue date: 2000 / Resumo: Este trabalho apresenta um método paramétrico de resolução do problema de Fluxo de Potência Ótimo (FPO) para sistemas de potência de grande porte. O trabalho é uma continuação das pesquisas anteriores em otimização paramétrica aplicada no FPO desenvolvidas na UNICAMP e na Universidade McGiII, em Montreal, Canadá. A abordagem paramétrica consiste em relaxar o problema original (FPO) através da incorporação de termos paramétricos na função objetivo e nas restrições de igualdade e desigualdade dando surgimento ao problema relaxado (Fluxo de Potência Ótimo Paramétrico­FPOP). A relaxação do FPO assegura que qualquer solução inicial arbitrária, factível ou não no problema original, seja solução ótima do FPO relaxado. Através da variação de um parâmetro, uma família de problemas paramétricos é resolvida pelo método de Newton-Raphson, cujas soluções formam um caminho que parte do problema relaxado indo até a solução do problema original. Uma estratégia eficiente para a determinação do conjunto de restrições de desigualdade ativas de cada problema paramétrico foi desenvolvida. O método foi testado em duas versões do sistema elétrico brasileiro Sul-Sudeste, uma contendo 810 barras e uma outra com 2256 barras na qual está representada a interligação do Sul-Sudeste com o Norte-Nordeste. Foram considerados os problemas de minimização do custo de geração, minimização de perdas ativas e minimização de desvio de tensão. Os resultados mostraram que a abordagem paramétrica é uma técnica robusta e eficiente de resolução de problemas de FPO em sistemas de grande porte / Abstract: The aim of this work is to present a parametric method for the resolution of the Optimal Power Flow (OPF) problem applied to large scale power systems. This research work on parametric optimization applied to OPF was developed at UNICAMP and at McGiII University, in Montreal, Canada. The parametric approach consists of relaxing the original problem (OPF) by incorporating parametric terms to the objective function and to the equality and inequality constraints leading to a relaxed problem (Parametric Optimal Power Flow ­POPF). The relaxation of the OPF assures that any arbitrary initial solution be the optimal solution of the relaxed OPF, even if this initial solution is feasible or not for the original problem. After a parameter change, a family of parametric problems is resolved by the Newton-Raphson method, whose solutions form a path from the relaxed problem up to the solution of the original problem. An efficient strategy was studied for the determination of the set of active inequality constraints for each parametric problem. The method was tested for two versions of the Brazilian South-Southeast power system, one containing 810 buses and another 2256 buses in which the South-Southeast to North-Northeast interconnection is represented. Problems concerned with minimization of generation costs, active losses and voltage profile were considered. The results showed that the parametric approach is a robust and efficient technique for the resolution of OPF problems for large scale power systems / Doutorado / Doutor em Engenharia Elétrica
313

Matemática financeira: conceitos e aplicações / Financial mathematics: concepts and applications

Teixeira, Adriano Rodrigues 07 August 2015 (has links)
Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2016-04-05T16:56:00Z No. of bitstreams: 2 Dissertação - Adriano Rodrigues Teixeira - 2015.pdf: 12601586 bytes, checksum: 7d86470df655890876bcda71442e2d53 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-04-06T11:04:20Z (GMT) No. of bitstreams: 2 Dissertação - Adriano Rodrigues Teixeira - 2015.pdf: 12601586 bytes, checksum: 7d86470df655890876bcda71442e2d53 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-04-06T11:04:20Z (GMT). No. of bitstreams: 2 Dissertação - Adriano Rodrigues Teixeira - 2015.pdf: 12601586 bytes, checksum: 7d86470df655890876bcda71442e2d53 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-08-07 / The essay brings the main concepts of financial mathematics, looking to directly connect it to the events in our surroundings. As such, we descant about interest, discounting, periodic cycles and amortization systems. We will also apply Newtons method in order to determine the interest rates on payment series. / O trabalho traz os principais conceitos da matemática financeira, buscando sempre fazer uma ligação imediata com os acontecimentos ao nosso redor. A saber, discorremos sobre juros, descontos, séries periódicas e sistemas de amortizações. Além disso, aplicaremos o método de Newton para determinar da taxa de juros de séries de pagamentos.
314

Um metodo Newton-GMRES globalmente convergente com uma nova escolha para o termo forçante e algumas estrategias para melhorar o desempenho de GMRES(m) / A globally convergent Newton-GMRES method with a new choice for the forcing term and some stragies to improve GMRES(m)

Toledo Benavides, Julia Victoria 17 June 2005 (has links)
Orientadores: Marcia A. Gomes Ruggiero, Vera Lucia da Rocha Lopes / Tese (doutorado) - Universidade Estadual de Campinas. Instituto de Matematica, Estatistica e Computação Cientifica / Made available in DSpace on 2018-08-04T14:53:24Z (GMT). No. of bitstreams: 1 ToledoBenavides_JuliaVictoria_D.pdf: 2835915 bytes, checksum: 1b77270a65a21cc42d9aa81819e4acc4 (MD5) Previous issue date: 2005 / Resumo: Neste trabalho, apresentamos um método de Newton inexato através da proposta de uma nova escolha para o termo forçante. O método obtido é globalizado através de uma busca linear robusta e suas propriedades de convergência são demonstradas. O passo de Newton inexato é obtido pela resolução do sistema linear através do método GMRES com recomeços, GMRES(m). Em testes computacionais observamos a ocorrência da estagnação em GMRES(m) e um acréscimo inaceitável na norma da função nas primeiras Iterações do método. Para contornar estas dificuldades são propostas estratégias de implementação computacional simples e que não exigem alterações internas no algoritmo do GMRES, possibilitando a interação com softwares já disponíveis. Exaustivos testes numéricos foram realizados, os quais nos permitiram concluir que a proposta para o termo for¸cante e as estratégias introduzidas foram bem sucedidas, resultando em um algoritmo robusto, com propriedade de convergência global e taxa superlinear de convergência / Abstract: In this work it is presented an inexact Newton method by a new choice for the forcing term. A globalization of the new method is done by introducing a robust line search strategy. Convergence properties are proved. The inexact Newton step is obtained through the restarted GMRES, GMRES (m), applied for solving the linear systems. Numerical experiments showed a stagnation of the GMRES (m) and also an occurrence of a great increase in the norm of the function at the initial iterations. Some strategies were proposed to avoid these drawbacks. These strategies are characterized by their simplicity of implementation and also by the fact that they do not need internal modifications of the GMRES algorithm. So, the interaction with available softwares are trivial. A bunch of numerical experiments were performed. With them it can be concluded that the new choice for the forcing term and the strategies incorporated in the algorithm were successfull. The resulting algorithm is then robust and has global convergence property with supelinear convergence rate / Doutorado / Doutor em Matemática Aplicada
315

Convergence of Asynchronous Jacobi-Newton-Iterations

Schrader, U. 30 October 1998 (has links) (PDF)
Asynchronous iterations often converge under different conditions than their syn- chronous counterparts. In this paper we will study the global convergence of Jacobi- Newton-like methods for nonlinear equationsF x = 0. It is a known fact, that the synchronous algorithm converges monotonically, ifF is a convex M-function and the starting valuesx0 andy0 meet the conditionF x04 04F y0 . In the paper it will be shown, which modifications are necessary to guarantee a similar convergence behavior for an asynchronous computation.
316

Solving Linear Matrix Equations via Rational Iterative Schemes

Benner, Peter, Quintana-Ortí, Enrique, Quintana-Ortí, Gregorio 01 September 2006 (has links) (PDF)
We investigate the numerical solution of stable Sylvester equations via iterative schemes proposed for computing the sign function of a matrix. In particular, we discuss how the rational iterations for the matrix sign function can efficiently be adapted to the special structure implied by the Sylvester equation. For Sylvester equations with factored constant term as those arising in model reduction or image restoration, we derive an algorithm that computes the solution in factored form directly. We also suggest convergence criteria for the resulting iterations and compare the accuracy and performance of the resulting methods with existing Sylvester solvers. The algorithms proposed here are easy to parallelize. We report on the parallelization of those algorithms and demonstrate their high efficiency and scalability using experimental results obtained on a cluster of Intel Pentium Xeon processors.
317

Craft Physics Interface

Hansson, Henrik January 2007 (has links)
This is a masters thesis (20p) in computer science at the University of Linköping. This thesis will give an introduction to what a physics engine is and what it consist of. It will put some engines under the magnifying glass and test them in a couple of runtime tests. Two cutting edge commercial physics engines have been examined, trying to predict the future of physics engines. From the research and test results, an interface for physics engine independency has been implemented for a company called Craft Animations in Gothenburg, Sweden.
318

Time performance comparison in determining the weak parts in wooden logs

Akhtar, Naeem, Alzghoul, Ahmad January 2009 (has links)
The steadily increasing demand of wood forces sawmills to increase the efficiency and effectiveness of their equipments. The weak parts and the twist in wooden logs have been documented as the most common and crucial defect in sawn lumber. In this thesis we are going to implement a program which is able to determine the weak parts in wooden logs. The implementation will be in two languages C++ and Matlab. Parts of the program are going to be implemented sometimes by C++ and sometimes by Matlab therefore different designs are going to be tested. The aim of this thesis is to check whether these designs will meet the real time bound of 10 m/s. The result shows that there is a huge difference in time performance for the different designs. Therefore, different discretization levels were used in order to meet the deadline of 10m/s. We found that in order to get better speed one should calculate the matrix for the function F and the Jacobian function J by using C++ not by Matlab. Also we found that when we called functions from one language to another an extra time is added.
319

The Matrix Sign Function Method and the Computation of Invariant Subspaces

Byers, R., He, C., Mehrmann, V. 30 October 1998 (has links) (PDF)
A perturbation analysis shows that if a numerically stable procedure is used to compute the matrix sign function, then it is competitive with conventional methods for computing invariant subspaces. Stability analysis of the Newton iteration improves an earlier result of Byers and confirms that ill-conditioned iterates may cause numerical instability. Numerical examples demonstrate the theoretical results.
320

Collision detection using boundary representation, BREP

Sandqvist, Jonas January 2015 (has links)
This thesis treats how to generate collision information for multibody simulations in AgX Dynamicswhere the geometries are described with the data structure boundary representation, BREP. BREP is adata structure that contains the exact mathematical description of each individual surface. To describecomplex surfaces exact and efficient non uniform rational basis spline, NURBS, is used and for trivialsurfaces like planes or spheres simpler equations is used. Since all surfaces in a BREP is described veryaccurate, the accuracy for the collision information can be set high without affecting the amount of dataneeded to describe the geometries.To make AgX Dynamics able to calculate forces in a multibody simulation, collision informationabout were and how much two geometries are intersecting is required. The collision information containswere the overlap between two geometries is, how much the objects have penetrated each other and thedirection for which the objects have to separate. To find the penetration depth and the overlap theNewton Raphson method were used. The experiments conducted, showed that it is possible to useBREPs as a description of geometries to produce the collision information needed for the physics engineused by AgX Dynamics to handle collisions. A comparison between trimesh and BREP for producingthe collision information, shows that data usage is much lower for the representation of geometries withBREPs than trimesh. The results also shows that the accuracy can be significantly higher than fortrimesh as the data usage for trimesh becomes non practical to handle when the required accuracy ishigh. With the high accuracy and with the smooth surfaces used with the BREP the artificial friction isalmost negligible except for cases were intersection points could not be found all around the intersectioncurves due to limitations in the algorithm. / Detta examensarbete behandlar hur man skapar kollisionsinformation för flerkropps simuleringar i AgXDynamics där geometrier beskrivs med datastrukturen boundary representation, BREP. BREP är endatastruktur som innehåller den exakta matematiska beskrivningen för varje enskild yta. Att beskrivakomplexa ytor exakta och effektivt med non uniform rationell basis spline, NURBS, används och förtriviala ytor som plan eller sfärer kan enklare ekvationer används. Eftersom alla ytor i en BREP beskrivsexakt, kan noggrannheten för kollisions informationen sättas högt utan att påverka den mängd data sombehövs för att beskriva geometrier.För att göra AgX Dynamics kunna beräkna krafter i en flerkroppssimulering, krävs kollisions informationom var och hur mycket två geometrier kolliderar. Kollisions informationen innehåller varöverlappningen mellan två geometrier är, hur mycket objekten har penetrerat varandra och den riktningsom föremålen ska separeras. För att hitta penetrationsdjup och överlapp användes Newton Raphsonsmetod. De experiment som utförts, visade att det är möjligt att använda BREPs som en beskrivning avgeometrier för att producera kollisions information som behövs för att den fysikmotor som används avAGX Dynamics ska kunna hantera kollisioner. En jämförelse mellan trimesh och BREP för att producerakollisionen informationen, visar att dataanvändning är mycket lägre när geometrier representeras medBREPs än trimesh. Resultaten visar också att noggrannheten kan vara väsentligt högre för BREP änför trimesh eftersom dataanvändning för trimesh blir opraktiskt att hantera när noggrannheten är hög.Med hög noggrannhet och med de släta ytor som används med BREP blev den artificiella friction nästanförsumbar, utom i fallen där skärningspunkter inte kunde hittas runt hela skärningskurvor på grund avbegränsningar i algoritmen.

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