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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.
641

Constribuições dos métodos simplex e das resoluções gráficas à aprendizagem da álgebra linear no Ensino Médio / Contributions of simplex methods and resolutions graphics for learning of linear algebra in high school

Vasconcelos, Eduardo Silva 12 April 2013 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-08-28T21:24:23Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Vasconcelos, Eduardo Silva..pdf: 1832341 bytes, checksum: c00d3ca071a0f15e55eeef2079d52047 (MD5) / Made available in DSpace on 2014-08-28T21:24:23Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Vasconcelos, Eduardo Silva..pdf: 1832341 bytes, checksum: c00d3ca071a0f15e55eeef2079d52047 (MD5) Previous issue date: 2013-04-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This paper aims to describe the Simplex Method and Method of Resolution Graphics problems on Linear Programming, aiming at the teaching and learning of linear algebra in high school. And for this, presents some basic concepts in linear programming, it follows brie y on the Simplex Method and Method of Resolution Graphics and presents two resolutions of Linear Programming problems, a maximization and minimization another, both problems are solved by two methods cited. We understand the importance of this work is to present the Simplex Method eao Method Graphical resolution to high school students because we believe that together these two methods applied in teaching linear algebra could lead to increased motivation of students in learning mathematics. / Este trabalho tem o objetivo de descrever o Método Simplex e o Método de Resoluções Grá cas em problemas de Programação Linear, visando o ensino e a aprendizagem da álgebra linear no Ensino Médio. E, para tal, apresenta alguns conceitos básicos em Programação Linear, decorre sucintamente sobre o Método Simplex e o Método de Resolução Grá ca e apresenta duas resoluções de problemas de Programação Linear, uma de maximização e outra de minimização, ambos os problemas são resolvidos pelos dois métodos citados. Entendemos que a importância deste trabalho está em apresentar o Método Simplex e a o Método de Resolução Grá ca aos alunos do Ensino Médio pois, acreditamos que estes dois métodos juntamente aplicados no ensino de álgebra linear poderá levar a uma maior motivação destes alunos na aprendizagem da matemática.
642

Topics in exact precision mathematical programming

Steffy, Daniel E. 24 January 2011 (has links)
The focus of this dissertation is the advancement of theory and computation related to exact precision mathematical programming. Optimization software based on floating-point arithmetic can return suboptimal or incorrect resulting because of round-off errors or the use of numerical tolerances. Exact or correct results are necessary for some applications. Implementing software entirely in rational arithmetic can be prohibitively slow. A viable alternative is the use of hybrid methods that use fast numerical computation to obtain approximate results that are then verified or corrected with safe or exact computation. We study fast methods for sparse exact rational linear algebra, which arises as a bottleneck when solving linear programming problems exactly. Output sensitive methods for exact linear algebra are studied. Finally, a new method for computing valid linear programming bounds is introduced and proven effective as a subroutine for solving mixed-integer linear programming problems exactly. Extensive computational results are presented for each topic.
643

Dynamical probabilistic graphical models applied to physiological condition monitoring

Georgatzis, Konstantinos January 2017 (has links)
Intensive Care Units (ICUs) host patients in critical condition who are being monitored by sensors which measure their vital signs. These vital signs carry information about a patient’s physiology and can have a very rich structure at fine resolution levels. The task of analysing these biosignals for the purposes of monitoring a patient’s physiology is referred to as physiological condition monitoring. Physiological condition monitoring of patients in ICUs is of critical importance as their health is subject to a number of events of interest. For the purposes of this thesis, the overall task of physiological condition monitoring is decomposed into the sub-tasks of modelling a patient’s physiology a) under the effect of physiological or artifactual events and b) under the effect of drug administration. The first sub-task is concerned with modelling artifact (such as the taking of blood samples, suction events etc.), and physiological episodes (such as bradycardia), while the second sub-task is focussed on modelling the effect of drug administration on a patient’s physiology. The first contribution of this thesis is the formulation, development and validation of the Discriminative Switching Linear Dynamical System (DSLDS) for the first sub-task. The DSLDS is a discriminative model which identifies the state-of-health of a patient given their observed vital signs using a discriminative probabilistic classifier, and then infers their underlying physiological values conditioned on this status. It is demonstrated on two real-world datasets that the DSLDS is able to outperform an alternative, generative approach in most cases of interest, and that an a-mixture of the two models achieves higher performance than either of the two models separately. The second contribution of this thesis is the formulation, development and validation of the Input-Output Non-Linear Dynamical System (IO-NLDS) for the second sub-task. The IO-NLDS is a non-linear dynamical system for modelling the effect of drug infusions on the vital signs of patients. More specifically, in this thesis the focus is on modelling the effect of the widely used anaesthetic drug Propofol on a patient’s monitored depth of anaesthesia and haemodynamics. A comparison of the IO-NLDS with a model derived from the Pharmacokinetics/Pharmacodynamics (PK/PD) literature on a real-world dataset shows that significant improvements in predictive performance can be provided without requiring the incorporation of expert physiological knowledge.
644

Um estudo do efeito da composição dos vidros teluretos sobre os índices de refração linear e não linear

Capanema Junior, Wilson Alves [UNESP] 20 August 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-08-20Bitstream added on 2014-06-13T20:53:38Z : No. of bitstreams: 1 capanemajunior_wa_me_ilha.pdf: 1306042 bytes, checksum: d90e8cb73761f2190b4d6d40b6bc20b3 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho foram estudadas as propriedades ópticas de vidros teluretos do sistema (20-x)Li2O-80TeO2-xTiO2 com x = 0, 5, 10 e 15 mol%. Foram preparadas amostras para cada uma das composições através do convencional método de “meltquenting”. Medimos, para cada amostra, o espectro de infravermelho e o espectro na faixa do ultravioleta-visível. Também obtemos os valores de índice de refração de cada amostra para diversos comprimentos de onda na faixa do visível. Para tanto, utilizamos um interferômetro de Michelson-Morley modificado. Medidas de densidade foram feitas utilizando-se o convencional método de Arquimedes. Por fim, foram feitas medidas do coeficiente térmico do caminho óptico através da interferometria. A análise estrutural foi feita através do espectro de infravermelho. Pode-se observar a tendência à formação de pirâmides trigonais em substituição às bipirâmides (encontradas no TeO2 cristalino) quando aumentamos a porcentagem de óxido de lítio. Uma análise qualitativa da absorção na faixa de interesse em comunicações ópticas (~1500 nm) foi feita através do espectro de infravermelho próximo, mostrando que nesta faixa temos a predominância do espalhamento Rayleigh, com o coeficiente de absorção proporcional a λ-4. Usando os dados da espectroscopia na faixa ultravioleta-visível foi possível observar a mudança das freqüências de corte para cada composição e ainda calcular a energia de gap e a energia de cauda de Urbach. Através do modelo clássico de osciladores harmônicos forçados de Wemple, os resultados de índice de refração foram interpretados. Buscou-se ainda relacionar as mudanças observadas para os valores medidos para cada composição com possíveis mudanças estruturais. Concluímos, usando as considerações de Wemple, que o aumento... / In this work had been studied tellurite glasses’s the optic properties of the system (20-x) Li2O-80TeO2-xTiO2 with x = 0, 5, 10 and 15 mol%. Samples for each one of the compositions through the conventional method of melt-quenting had been prepared. We measure, for each sample, the infra-red ray specter and the specter in the band of the ultraviolet-visible one. Also we get the values of refractive index of each sample for diverse wave lengths in the visible band. For in such a way, we use a modified interferometer of Michelson-Morley. Measures of density had been made using the conventional method of Archimedes. Finally, they had been made measured of the thermal coefficient of the optic way through the interferometry. The structural analysis was made through the infra-red ray specter. The trend to the formation of trigonais pyramids in substitution to the bipyramids can be observed (found in the crystalline TeO2) when increases the lithium oxide percentage. A qualitative analysis of the absorption in the band of interest in optic communications (~1500 nm) was made through the infra-red ray specter, showing that in this band we have the predominance of the Rayleigh scattering, with the coefficient of absorption proportional to λ-4. Using the data of the spectroscopy in the ultraviolet-visible band to each composition was possible to observe the change of the cut-off frequencies and still to calculate the energy of gap and the energy of Urbach. Through the classic model of forced harmonic oscillators of Wemple, the results of refractive index had been interpreted. We still searched to relate the changes observed for the values measured for each composition with possible structural changes. We conclude, using the considerations of Wemple, that the increase for the values of... (Complete abstract click electronic access below)
645

Algoritmo de tomografia por impedância elétrica utilizando programação linear como método de busca da imagem. / Algorithm of electrical impedance tomography using linear programming as method of searching image.

Miguel Fernando Montoya Vallejo 14 November 2007 (has links)
A Tomografia por Impedância elétrica (TIE) tem como objetivo gerar imagens da distribuição de resistividade dentro de um domínio. A TIE injeta correntes em eletrodos alocados na fronteira do domínio e mede potenciais elétricos através dos mesmos eletrodos. A TIE é considerada um problema inverso, não-linear e mal posto. Atualmente, para gerar uma solução do problema inverso, existem duas classes de algoritmos para estimar a distribuição de resistividade no interior do domínio, os que estimam variações da distribuição de resistividade do domínio e os absolutos, que estimam a distribuição de resistividade. Variações da distribuição de resistividade são o resultado da solução de um sistema linear do tipo Ax = b. O objetivo do presente trabalho é avaliar o desempenho da Programação Linear (PL) na solução do sistema linear, avaliar o algoritmo quanto a propaga- ção de erros numéricos e avaliar os efeitos de restringir o espaço solução através de restrições de PL. Os efeitos do uso de Programação Linear é avaliado tanto em métodos que geram imagens de diferenças, como o Matriz de Sensibilidade, como em métodos absolutos, como o Gauss-Newton. Mostra-se neste trabalho que o uso da PL diminui o erro numérico propagado quando comparado ao uso do algoritmo LU Decomposition. Resulta também que reduzir o espaço solução, diretamente através de restrições de PL, melhora a resolução em resistividade e a resolução espacial da imagem quando comparado com o uso de LU Decomposition. / Electrical impedance tomography (EIT) generates images of the resistivity distribution of a domain. The EIT method inject currents through electrodes placed on the boundary of the domain and measures electric potentials through the same electrodes. EIT is considered an inverse problem, non-linear and ill-conditioned. There are two classes of algorithms to estimate the resistivity distribution inside the domain, difference images algorithms, which estimate resistivity distribution variations, and absolute images algorithms, which estimate the resistivity distribution. Resistivity distribution variations are the solution of a linear system, say Ax = b. In this work, the main objective is to evaluate the performance of Linear Programming (LP) solving an EIT linear system from the point of view of the numerical error propagation and the ability to constrain the solution space. The impact of using LP to solve an EIT linear system is evaluated on a difference image algorithm and on an absolute algorithm. This work shows that the use of LP diminishes the numerical error propagation compared to LU Decomposition. It is also shown that constraining the solution space through LP improves the resistivity resolution and the spatial resolution of the images when compared to LU Decomposition.
646

Pré-despacho de usinas hidrelétricas = implementação com algoritmos genéticos / Dispatch hydroelectric power plants : implementation with genetic algorithms

Fernandes, Jéssica Pillon Torralba, 1985- 02 February 2011 (has links)
Orientador: Paulo de Barros Correia / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-17T15:00:07Z (GMT). No. of bitstreams: 1 Fernandes_JessicaPillonTorralba_M.pdf: 4647228 bytes, checksum: e46a85d1f8f415429fb623b7f6feeee1 (MD5) Previous issue date: 2011 / Resumo: Esta dissertação de mestrado tem por objetivo apresentar e implementar um modelo de otimização da operação diária das usinas hidrelétricas do Médio São Francisco. O estudo considera oito usinas do sistema - Sobradinho, Luiz Gonzaga, Apolônio Sales, Paulo Afonso I, II, III e IV e Xingó - pertencentes à Companhia Hidro Elétrica do São Francisco. Seu objetivo é maximizar eficiência de geração das usinas e minimizar o número de partidas e paradas de suas unidades eradoras, simultaneamente. A técnica de resolução é feita em duas etapas, sendo que a Etapa 1 determina quanto cada usina deve gerar a cada intervalo de tempo, e a Etapa 2 determina o número de unidades geradoras em operação e a carga de uma usina específica. A formulação matemática do problema proposto é de natureza não linear inteira mista e, para solucionar o modelo foram utilizadas técnicas de Computação evolutiva, em específico os Algoritmos genéticos, e de Programação linear. Esta metodologia foi desenvolvida com dois programas computacionais, ambos comerciais sendo um software com linguagem de programação de quarta geração. Um dos programas foi utilizado para a interface, enquanto no de quarta geração, o modelo de otimização foi implementado. A solução obtida aumenta a eficiência em relação ao despacho atual e em relação as restrições operativas usuais. A aplicabilidade deste modelo pode ser utilizada na otimização de outras usinas em cascata / Abstract: This dissertation aims to presents and implement an optimization model for daily operation of Middle São Francisco River hydroeletric system. The study considers eight power plants - Sobradinho, Luiz Gonzaga, Apolônio Sales, Paulo Afonso I, II, III, IV e Xingó - witch belongs to the São Francisco Hydroeletric Company. Its objective is to maximize the power plant efficiency and, simultaneously, to minimize the number of startups and shutdowns of generating units. The technique of resolution is made in two steps: Step 1 determines the load allocated to each power plant at each hour; Step 2 defines the number of generating units in operation and the load of particular power plant. The mathematical formulation is non-linear mixed integer programs and solved with a Genetic Algorithm (GA) approad, and Linear Programming . This model was implemented with two computation programs, One a commercial optimization solver, and a in house GA solver coded with a programming language of fourth generation. One of the programs was used to interface, while the fourth generation, the optimization model was implemented. This solution increases effi- ciency in relation to the actual dispatch and for the usual operational restrictions. The applicability of this model can be used for the optimization of other plants in cascade / Mestrado / Planejamento de Sistemas Energeticos / Mestre em Planejamento de Sistemas Energéticos
647

Uma proposta do ensino de programação linear no ensino médio / A proposal of education of linear programming in secondary education

Lyra, Marcelo Simplicio de 02 July 2014 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-01-16T13:17:29Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Marcelo Simplício de Lyra - 2014.pdf: 2216498 bytes, checksum: e17b32a5feca5b8118ebc97a0684a160 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-01-16T13:45:49Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Marcelo Simplício de Lyra - 2014.pdf: 2216498 bytes, checksum: e17b32a5feca5b8118ebc97a0684a160 (MD5) / Made available in DSpace on 2015-01-16T13:45:49Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Marcelo Simplício de Lyra - 2014.pdf: 2216498 bytes, checksum: e17b32a5feca5b8118ebc97a0684a160 (MD5) Previous issue date: 2014-07-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This research presents a new approach that aims to introduce linear programming into the high school taking into account the teaching techniques, teacher and student profiles, and the flexibility of the curriculum. The context of the linear programming involves problems with two or three variables, since problems with many variables cannot be easily considered in a high school curriculum, especially due to the time required to solve such problems. The approach is developed under an algebraic point of view, in which the linear problem‟s solutions are obtained by a resolution of systems of linear equations. The approach also considers a numerical and computer simulation software, denominated Octave®, in order to solve those systems of linear equations and, consequently, this software may be used as a tool that allows extending such approach to solve linear programming problems with several decision variables. / Esta pesquisa apresenta uma proposta de introdução da programação linear no ensino médio levando em consideração os métodos de ensino, o perfil profissional do professor, o perfil do estudante e a flexibilização do currículo escolar. O contexto da programação linear envolve problemas de duas ou três variáveis, uma vez que problemas com mais variáveis podem não se adequar ao currículo do ensino médio, em especial pelo fator tempo. Parte-se de um desenvolvimento algébrico, em que as soluções do problema são obtidas por meio da resolução de vários sistemas de equações lineares. A proposta também inclui utilizar um software de simulação numérica e computacional, denominado Octave®, para a resolução dos vários sistemas lineares e, consequentemente, ser usado como uma estratégia para estender a proposta para problemas de programação linear com várias variáveis de decisão.
648

Process for creation of sustainable web 2.0 based interactive demonstration and content for control education

Updyke, Joshua C. January 1900 (has links)
Master of Science / Department of Mechanical and Nuclear Engineering / Warren N. White / The objective of this research was to show that controls demonstrations and education can be greatly improved with the use of Web 2.0 tools. First, a user-centered and collaborative website was developed using the freely available Web 2.0 tools. Then procedures for creating animations using control system simulations were developed. Using the Java programming language, interactive graphs were constructed for display to allow the viewer to change the initial conditions of the controls system and plot the results of the simulation as calculated. These animations and interactive graphs used already developed MatLab resources. Using Web 2.0 tools, the collaborative web site can be easily updated by several people simultaneously, only requiring access to the internet. Because of these advantages, collaboration between multiple universities and controls researchers in distant locations is possible, and the new website has the potential of becoming the center of controls research around the world. More importantly, the procedure allows future systems to be demonstrated while requiring minimal additional work, thereby increasing the universities' ability to educate their students, as well as the general public, about controls system research.
649

An in-core linear programming model of the high-temperature gas- cooled reactor

Miller, Joseph Sheridan January 2011 (has links)
Digitized by Kansas Correctional Industries
650

A procedure for applying linear programming to the formula feed warehouse cost-center

Rees, Richard Dale January 2011 (has links)
Digitized by Kansas State University Libraries

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