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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.
191

A poesia e a política de Newton Moreno: estudo de caso de Agreste e A Cicatriz é a Flor / The Newton Moreno´s poetry and pplitics: A case study of Agreste and The Scar is the Flower

Santi, Lissa Augusta Duarte 06 November 2018 (has links)
Este projeto se propõe a analisar as obras A Cicatriz é a Flor e Agreste, ambas do dramaturgo brasileiro Newton Moreno, com o propósito de melhor compreender os limites do drama relacionado à forma épica e lírica no teatro, tendo como foco principal o envolvimento deste último com o gênero lírico. Paralelamente a isso, pretende-se analisar o estofo político dessas obras, identificando os assuntos sociais de que tratam por meio do lirismo e do olhar subjetivo do autor, que empresta o olhar de mulheres homossexuais em embate com nosso contexto social homofóbico e machista. As citadas análises, em paralelo, visam a pesquisa dos possíveis embricamentos que podem ocorrer entre o teatro lírico e o teatro político. / This project proposes to analyze the written works The Scar is the Flower and Agreste, both of the Brazilian playwright Newton Moreno, with the purpose of better understanding the limits of the drama related to the epic and lyrical form in the theater, having as main focus the theater itself with the lyrical genre. Parallel to this, we intend to analyze the political reasoning of these plays, identifying the social issues they deal with through lyricism and the subjective view of the author, which lends the look of homosexual women in conflict with our homophobic and male chauvinist social context. The aforementioned analyzes, in parallel, seek to investigate the possible nexus that may occur between lyrical theater and political theater.
192

Inexact Newton Methods Applied to Under-Determined Systems

Simonis, Joseph P 04 May 2006 (has links)
Consider an under-determined system of nonlinear equations F(x)=0, F:R^m→R^n, where F is continuously differentiable and m > n. This system appears in a variety of applications, including parameter-dependent systems, dynamical systems with periodic solutions, and nonlinear eigenvalue problems. Robust, efficient numerical methods are often required for the solution of this system. Newton's method is an iterative scheme for solving the nonlinear system of equations F(x)=0, F:R^n→R^n. Simple to implement and theoretically sound, it is not, however, often practical in its pure form. Inexact Newton methods and globalized inexact Newton methods are computationally efficient variations of Newton's method commonly used on large-scale problems. Frequently, these variations are more robust than Newton's method. Trust region methods, thought of here as globalized exact Newton methods, are not as computationally efficient in the large-scale case, yet notably more robust than Newton's method in practice. The normal flow method is a generalization of Newton's method for solving the system F:R^m→R^n, m > n. Easy to implement, this method has a simple and useful local convergence theory; however, in its pure form, it is not well suited for solving large-scale problems. This dissertation presents new methods that improve the efficiency and robustness of the normal flow method in the large-scale case. These are developed in direct analogy with inexact-Newton, globalized inexact-Newton, and trust-region methods, with particular consideration of the associated convergence theory. Included are selected problems of interest simulated in MATLAB.
193

UMA PROPOSTA DE UTILIZAÇÃO DE MÍDIAS SOCIAIS NO ENSINO DE FÍSICA PARA AS TURMAS DE 1° ANO DO ENSINO MÉDIO, COM ÊNFASE À DINÂMICA DE NEWTON / UMA PROPOSTA DE UTILIZAÇÃO DE MÍDIAS SOCIAIS NO ENSINO DE FÍSICA PARA AS TURMAS DE 1° ANO DO ENSINO MÉDIO, COM ÊNFASE À DINÂMICA DE NEWTON / A PROPOSAL FOR USE OF SOCIAL MEDIA IN TEACHING PHYSICS FOR THE CLASSES OF FIRST YEAR OF HIGH SCHOOL, WITH EMPHASIS ON THE DYNAMICS OF NEWTON / A PROPOSAL FOR USE OF SOCIAL MEDIA IN TEACHING PHYSICS FOR THE CLASSES OF FIRST YEAR OF HIGH SCHOOL, WITH EMPHASIS ON THE DYNAMICS OF NEWTON

Lara, Heterson Luiz de 30 September 2016 (has links)
Made available in DSpace on 2017-07-24T19:45:50Z (GMT). No. of bitstreams: 1 Heterson Luiz de Lara.pdf: 4325372 bytes, checksum: d579504081b71feb827fa104cf18ecaf (MD5) Previous issue date: 2016-09-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work presents an alternative to the teaching of Physics for the first year of high school, with emphasis on the Dynamic teaching and using as a pedagogycal tool social networking WhatsApp. Was applied in a public school with classes in the series proposal, presents all development activities, theoretical and methodological discussion and mainly the results obtained, shows that it is possible to break away from the traditional teaching of kinematics and with excessive mathematical formalism traditional without, however, abandoning what is also important in this form of education and of the mathematical formalism necessary. The use of WhatsApp as a pedagogycal tool is an alternative proposal that caters to the emergence of new forms of communication, something that is quite present in school environments, but are not always used. The results of the application of the work show that in this sense can mitigate also the conflict generated by the excessive use of smartphones in the classroom and have a form of communication and Physical content sharing within and outside of the classroom. Also, features a class based on the proposal and intends to be an element of pedagogical support to physics teaching in classes from first year of high school. / Este trabalho apresenta uma alternativa para o ensino da disciplina de Física para o primeiro ano do Ensino Médio, com ênfase ao ensino da Dinâmica e utilizando como ferramenta pedagógica a rede social WhatsApp. Foi aplicado em uma escola pública com turmas da série proposta, apresenta todo o desenvolvimento das atividades, a discussão teórica e metodológica e, principalmente os resultados obtidos, mostra que é possível romper com o ensino tradicional de Cinemática e com o formalismo matemático tradicional sem, contudo, abandonar o que é também importante nesta forma de ensino e do formalismo matemático necessário. A utilização do WhatsApp como ferramenta pedagógica é uma proposta alternativa que atende ao surgimento das novas formas de comunicação, algo que está bastante presente nos ambientes escolares, porém nem sempre são aproveitadas. Os resultados da aplicação do trabalho mostram que neste sentido pode-se amenizar também o conflito gerado pela utilização excessiva de smartphones em sala de aula e, ainda, ter uma forma de comunicação e compartilhamento de conteúdo de Física dentro e fora de sala de aula. Também apresenta um roteiro de aulas com base na proposta e se propõe a ser um elemento de apoio pedagógico ao ensino de Física em turmas de primeiro ano do Ensino Médio.
194

Méthodes de décomposition de domaines en temps et en espace pour la résolution de systèmes d’EDOs non-linéaires / Time and space domain decomposition method for nonlinear ODE

Linel, Patrice 05 July 2011 (has links)
La complexification de la modélisation multi-physique conduit d’une part à devoir simuler des systèmes d’équations différentielles ordinaires et d’équations différentielles algébriques de plus en plus grands en nombre d’inconnues et sur des temps de simulation longs. D’autre part l’évolution des architectures de calcul parallèle nécessite d’autres voies de parallélisation que la décomposition de système en sous-systèmes. Dans ce travail, nous proposons de concevoir des méthodes de décomposition de domaine pour la résolution d’EDO en temps. Nous reformulons le problème à valeur initiale en un problème aux valeurs frontières sur l’intervalle de temps symétrisé, sous l’hypothèse de réversibilité du flot. Nous développons deux méthodes, la première apparentée à une méthode de complément de Schur, la seconde basée sur une méthode de type Schwarz dont nous montrons la convergence pouvant être accélérée par la méthode d’Aitken dans le cadre linéaire. Afin d’accélérer la convergence de cette dernière dans le cadre non-linéaire, nous introduisons les techniques d’extrapolation et d’accélération de la convergence des suites non-linéaires. Nous montrons les avantages et les limites de ces techniques. Les résultats obtenus nous conduisent à développer l’accélération de la méthode de type Schwarz par une méthode de Newton. Enfin nous nous intéressons à l’étude de conditions de raccord non-linéaires adaptées à la décomposition de domaine de problèmes non-linéaires. Nous nous servons du formalisme hamiltonien à ports, issu du domaine de l’automatique, pour déduire les conditions de raccord dans le cadre l’équation de Saint-Venant et de l’équation de la chaleur non-linéaire. Après une étude analytique de la convergence de la DDM associée à ces conditions de transmission, nous proposons et étudions une formulation de Lagrangien augmenté sous l’hypothèse de séparabilité de la contrainte. / Complexification of multi-physics modeling leads to have to simulate systems of ordinary differential equations and algebraic differential equations with increasingly large numbers of unknowns and over large times of simulation. In addition the evolution of parallel computing architectures requires other ways of parallelization than the decomposition of system in subsystems. In this work, we propose to design domain decomposition methods in time for the resolution of EDO. We reformulate the initial value problem in a boundary values problem on the symmetrized time interval, under the assumption of reversibility of the flow. We develop two methods, the first connected with a Schur complement method, the second based on a Schwarz type method for which we show convergence, being able to be accelerated by the Aitken method within the linear framework. In order to accelerate the convergence of the latter within the non-linear framework, we introduce the techniques of extrapolation and of acceleration of the convergence of non-linear sequences. We show the advantages and the limits of these techniques. The obtained results lead us to develop the acceleration of the method of the type Schwarz by a Newton method. Finally we investigate non-linear matching conditions adapted to the domain decomposition of nonlinear problems. We make use of the port-Hamiltonian formalism, resulting from the control field, to deduce the matching conditions in the framework of the shallow-water equation and the non-linear heat equation. After an analytical study of the convergence of the DDM associated with these conditions of transmission, we propose and study a formulation of augmented Lagrangian under the assumption of separability of the constraint.
195

Accélération de la convergence de méthodes numériques parallèles pour résoudre des systèmes d’équations différentielles linéaires et transitoires non linéaires / Convergence acceleration of parallel numerical methods to solve nonlinear time-dependent and linear systems of differential equations

Berenguer, Laurent 13 October 2014 (has links)
La résolution des équations différentielles (EDP/EDO/EDA) est au cœur de la simulation de phénomènes physiques. L'accroissement de la taille et de la complexité des modèles nécessite la mise en œuvre de méthodes de résolution robustes et performantes en termes de temps de calcul. L'objectif de cette thèse est de proposer des méthodes pour accélérer la résolution des équations différentielles par des méthodes de décomposition de domaine. On considère d'abord les méthodes de décomposition de domaine de Schwarz pour la résolution de grands systèmes linéaires issus de la discrétisation d'EDP. Afin d'accélérer la convergence de la méthode de Schwarz, on propose une approximation de l'opérateur de propagation d'erreur. Cette approximation respectera la structure de l'opérateur exact, ce qui conduira à une réduction très significative des temps de calcul sur le problème des écoulements dans les milieux poreux hétérogènes. La deuxième contribution concerne la résolution de la suite de systèmes linéaires provenant de l'intégration en temps de problèmes non linéaires. On propose deux approches en utilisant le fait que la matrice jacobienne ne varie que peu d'un système à l'autre. Premièrement, on applique la mise à jour de Broyden au préconditionneur RAS (Restricted Additive Schwarz) au lieu de recalculer les factorisations LU. La deuxième approche consiste à dédier des processeurs a la mise à jour partielle et asynchrone du préconditionneur RAS. Des résultats numériques sur le problème de la cavité entrainée et sur un problème de réactiondiffusion montrent qu'une accélération super linéaire peut être obtenue. La dernière contribution a pour objet la résolution simultanée des problèmes non linéaires de pas de temps consécutifs. On étudie le cas où la méthode de Broyden est utilisée pour résoudre ces problèmes non linéaires. Dans ce cas, la mise à jour de Broyden peut être propagée d'un pas de temps à l'autre. La parallélisation à travers les pas de temps est également appliquée a la recherche d'une solution initiale consistante pour les équations différentielles algébriques / Solving differential equations (PDEs/ODEs/DAEs) is central to the simulation of physical phenomena. The increase in size and complexity of the models requires the design of methods that are robust and efficient in terms of computational time. The aim of this thesis is to design methods that accelerate the solution of differential equations by domain decomposition methods. We first consider Schwarz domain decomposition methods to solve large-scale linear systems arising from the discretization of PDEs. In order to accelerate the convergence of the Schwarz method, we propose an approximation of the error propagation operator. This approximation preserves the structure of the exact operator. A significant reduction of computational time is obtained for the groundwater flow problem in highly heterogeneous media. The second contribution concerns solving the sequence of linear systems arising from the time-integration of nonlinear problems. We propose two approaches, taking advantage of the fact that the Jacobian matrix does not change dramatically from one system to another. First, we apply Broyden’s update to the Restricted Additive Schwarz (RAS) preconditioner instead of recomputing the local LU factorizations. The second approach consists of dedicating processors to the asynchronous and partial update of the RAS preconditioner. Numerical results for the lid-driven cavity problem, and for a reaction-diffusion problem show that a super-linear speedup may be achieved. The last contribution concerns the simultaneous solution of nonlinear problems associated to consecutive time steps. We study the case where the Broyden method is used to solve these nonlinear problems. In that case, Broyden’s update of the Jacobian matrix may also be propagated from one time step to another. The parallelization through the time steps is also applied to the problem of finding a consistent initial guess for differential-algebraic equations
196

Form generation through filmed references : Charles River Baths

Sloan, William Henderson January 1977 (has links)
Thesis. 1977. M.Arch.--Massachusetts Institute of Technology. Dept. of Architecture. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH. / Bibliography : leaves 67-68. / by William Henderson Sloan Jr. / M.Arch.
197

Tópicos em penalidades exatas diferenciáveis / Topics in differentiable exact penalties

Fukuda, Ellen Hidemi 11 March 2011 (has links)
Durante as décadas de 70 e 80, desenvolveram-se métodos baseados em penalidades exatas diferenciáveis para resolver problemas de otimização não linear com restrições. Uma desvantagem dessas penalidades é que seus gradientes contêm termos de segunda ordem em suas fórmulas, o que impede a utilização de métodos do tipo Newton para resolver o problema. Para contornar essa dificuldade, utilizamos uma ideia de construção de penalidade exata para desigualdades variacionais, introduzida recentemente por André e Silva. Essa construção consiste em incorporar um estimador de multiplicadores, proposto por Glad e Polak, no lagrangiano aumentado para desigualdades variacionais. Nesse trabalho, estendemos o estimador de multiplicadores para restrições gerais de igualdade e desigualdade, e enfraquecemos a hipótese de regularidade. Como resultado, obtemos uma função penalidade exata continuamente diferenciável e uma nova reformulação do sistema KKT associado a problemas não lineares. A estrutura dessa reformulação permite a utilização do método de Newton semi-suave, e a taxa de convergência local superlinear pode ser provada. Além disso, verificamos que a penalidade exata construída pode ser usada para globalizar o método, levando a uma abordagem do tipo Gauss-Newton. Por fim, realizamos experimentos numéricos baseando-se na coleção CUTE de problemas de teste. / During the 1970\'s and 1980\'s, methods based on differentiable exact penalty functions were developed to solve constrained optimization problems. One drawback of these functions is that they contain second-order terms in their gradient\'s formula, which do not allow the use of Newton-type methods. To overcome such difficulty, we use an idea for construction of exact penalties for variational inequalities, introduced recently by André and Silva. This construction consists on incorporating a multipliers estimate, proposed by Glad and Polak, in the augmented Lagrangian function for variational inequalities. In this work, we extend the multipliers estimate to deal with both equality and inequality constraints and we weaken the regularity assumption. As a result, we obtain a continuous differentiable exact penalty function and a new equation reformulation of the KKT system associated to nonlinear problems. The formula of such reformulation allows the use of semismooth Newton method, and the local superlinear convergence rate can be also proved. Besides, we note that the exact penalty function can be used to globalize the method, resulting in a Gauss-Newton-type approach. We conclude with some numerical experiments using the collection of test problems CUTE.
198

Étude d’algorithmes de restauration d’images sismiques par optimisation de forme non linéaire et application à la reconstruction sédimentaire. / Seismic images restoration using non linear optimization and application to the sedimentary reconstruction.

Gilardet, Mathieu 19 December 2013 (has links)
Nous présentons une nouvelle méthode pour la restauration d'images sismiques. Quand on l'observe, une image sismique est le résultat d'un système de dépôt initial qui a été transformé par un ensemble de déformations géologiques successives (flexions, glissement de la faille, etc) qui se sont produites sur une grande période de temps. L'objectif de la restauration sismique consiste à inverser les déformations pour fournir une image résultante qui représente le système de dépôt géologique tel qu'il était dans un état antérieur. Classiquement, ce procédé permet de tester la cohérence des hypothèses d'interprétations formulées par les géophysiciens sur les images initiales. Dans notre contribution, nous fournissons un outil qui permet de générer rapidement des images restaurées et qui aide donc les géophysiciens à reconnaître et identifier les caractéristiques géologiques qui peuvent être très fortement modifiées et donc difficilement identifiables dans l'image observée d'origine. Cette application permet alors d'assister ces géophysiciens pour la formulation d'hypothèses d'interprétation des images sismiques. L'approche que nous introduisons est basée sur un processus de minimisation qui exprime les déformations géologiques en termes de contraintes géométriques. Nous utilisons une approche itérative de Gauss-Newton qui converge rapidement pour résoudre le système. Dans une deuxième partie de notre travail nous montrons différents résultats obtenus dans des cas concrets afin d'illustrer le processus de restauration d'image sismique sur des données réelles et de montrer comment la version restaurée peut être utilisée dans un cadre d'interprétation géologique. / We present a new method for seismic image restoration. When observed, a seismic image is the result of an initial deposit system that has been transformed by a set of successive geological deformations (folding, fault slip, etc) that occurred over a large period of time. The goal of seismic restoration consists in inverting the deformations to provide a resulting image that depicts the geological deposit system as it was in a previous state. With our contribution, providing a tool that quickly generates restored images helps the geophysicists to recognize geological features that may be too strongly altered in the observed image. The proposed approach is based on a minimization process that expresses geological deformations in terms of geometrical constraints. We use a quickly-converging Gauss-Newton approach to solve the system. We provide results to illustrate the seismic image restoration process on real data and present how the restored version can be used in a geological interpretation framework.
199

A poesia e a política de Newton Moreno: estudo de caso de Agreste e A Cicatriz é a Flor / The Newton Moreno´s poetry and pplitics: A case study of Agreste and The Scar is the Flower

Lissa Augusta Duarte Santi 06 November 2018 (has links)
Este projeto se propõe a analisar as obras A Cicatriz é a Flor e Agreste, ambas do dramaturgo brasileiro Newton Moreno, com o propósito de melhor compreender os limites do drama relacionado à forma épica e lírica no teatro, tendo como foco principal o envolvimento deste último com o gênero lírico. Paralelamente a isso, pretende-se analisar o estofo político dessas obras, identificando os assuntos sociais de que tratam por meio do lirismo e do olhar subjetivo do autor, que empresta o olhar de mulheres homossexuais em embate com nosso contexto social homofóbico e machista. As citadas análises, em paralelo, visam a pesquisa dos possíveis embricamentos que podem ocorrer entre o teatro lírico e o teatro político. / This project proposes to analyze the written works The Scar is the Flower and Agreste, both of the Brazilian playwright Newton Moreno, with the purpose of better understanding the limits of the drama related to the epic and lyrical form in the theater, having as main focus the theater itself with the lyrical genre. Parallel to this, we intend to analyze the political reasoning of these plays, identifying the social issues they deal with through lyricism and the subjective view of the author, which lends the look of homosexual women in conflict with our homophobic and male chauvinist social context. The aforementioned analyzes, in parallel, seek to investigate the possible nexus that may occur between lyrical theater and political theater.
200

Le livre II des Principia, les principes à l’épreuve de leur passage sur terre / Book II of Newton's Principia : Principles put to the test when applied to earth

Slowik, Claude 16 January 2014 (has links)
Le livre : Principia Mathematica Philosophiae Naturalis (1687) de Isaac Newton constitue pour la science moderne un texte fondateur. Le corps de cet ouvrage est constitué de trois parties principales appelées livres. Parmi ces trois livres, les livres I et III consacrés principalement à l'étude du cosmos ont fait l'objet de nombreuses études. Le livre II consacré à l'étude de la résistance au mouvement des milieux fluides a été quelque peu délaissé et même dévalorisé par l'historiographie. Dans le livre II Newton détourne son regard du ciel et le porte sur terre. L'étude de cette partie des Principia nous permet de : revisiter et d'approfondir le concept newtonien de force, de découvrir l'usage de la notion de pression, de préciser le rôle de la géométrie euclidienne. Pour la géométrie nous avons été particulièrement attentif aux différentes fonctions des figures. Nous avons travaillé à partir de plusieurs traductions, principalement celle de la marquise du Châtelet de 1759 et de celle plus récente de Cohen et Whitman. Nos référents essentiels sont : Blay, Cohen, De Gand, Janiak, Koyré, McMullin, Smith et Westfall. / Book : Isaac Newton's Principia Mathematica Philosophiae Naturalis (1687) represents a fundamental text for modern science. The body of that work is in three major parts called books. Among these three books, I and III are primarily dedicated to the study of the cosmos and have been the objects of numerous studies. Book II is dedicated to the study of resistance to movement of fluid environments and has been somewhat ignored and even devalued by historiography. In book II Newton turns away from the sky and looks down at earth. The study of that part of Principia allows us to revisit and deepen our knowledge of the newtonian concept of force, to discover and learn how to use the concept of pressure, and to clarify the role of euclidean geometry. As for geometry, we have paid special attention to the different functions of figures. We have worked with several translations, primarily Marquise du Chatelet 1759's translation, and the more recent one by Cohen and Whitman. Our essential references are Blay, Cohen, De Gand, Janiak, Koyre, McMullin, Smith and Westfall.

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