Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2018-11-12T12:12:57Z No. of bitstreams: 2 Dissertação - Luciane Nunes Ribeiro - 2018.pdf: 1973828 bytes, checksum: b219699558677772c9abb1ebe0b5d42f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-11-12T13:10:00Z (GMT) No. of bitstreams: 2 Dissertação - Luciane Nunes Ribeiro - 2018.pdf: 1973828 bytes, checksum: b219699558677772c9abb1ebe0b5d42f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-11-12T13:10:00Z (GMT). No. of bitstreams: 2 Dissertação - Luciane Nunes Ribeiro - 2018.pdf: 1973828 bytes, checksum: b219699558677772c9abb1ebe0b5d42f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-09-20 / This research analyzes the constitution's movements of the University in Europe and in Brazil; the creation of Mathematics’ first course in Brazil; the constitution of the contents which make up the Linear Algebra discipline syllabus and, finally, its current discipline syllabus in the presential courses in Mathematics Degree of the Brazilian Federal Universities. The purpose of the mentioned analysis is to answer the following research question: how did occur the contents' constitution that compose the syllabus of Linear Algebra in Mathematics degrees of Brazilian Federal Universities? In order to reach this objective, the bibliographical and documentary study were used as methodology, especially classical, history and yearbooks, legislation and the syllabus. The theoretical reference is based on Historical-Cultural Theory assumptions, which is scientific, but also political (MOURA, 2017; VYGOTSKI, 1995; CEDRO, 2008; OLIVEIRA, 2002; ZANELLA, 2007), through the study of logical- historical movement – defended by Kopnin, 1978; Sousa, Panossian, Cedro, 2014; Sousa, 2004; Fazenda, 2000 – of Algebra Linear discipline constitution, according to Pires, 2006; Dorier, 2000, Silva, 2003; Moore, 1995. It was necessary to understand the reasons of its inclusion in the university context and its contribution to the professional formation of Mathematics teacher, according to Bastos (1980; 2006), Boyer (1974), Cavalari (2012), Celestino (2000), Garding (1981), Kopnin (1978), Caraça (1959), Ríbnikov (1987), Tubino (1984), Kleiner (2007), among others. It was analyzed 55 Federal Brazilian Universities that offer presential course of Degree in Mathematics. As categories of analysis were stablished the content of syllabus, the workload and the basic bibliographic reference of compulsory discipline of Linear Algebra of these institutions. As more relevant conclusions, it was observed that Linear Algebra began to be developed and taught in Universities to solve practical problems of diverse intellectuals of engineering and exact sciences, and that the transfer of its indexes in an unrelated way may contribute to the difficulties in teaching and learning process present in this discipline. / Matemática das Universidades Federais Brasileiras. O objetivo dessa análise é o de responder à seguinte questão de pesquisa: como se deu a constituição dos conteúdos que compõem a ementa da disciplina de Álgebra Linear nos cursos de Licenciatura em Matemática das Universidades Federais Brasileiras? Para atingir o objetivo, utilizou-se como metodologia o estudo bibliográfico e documental, mormente de obras clássicas, livros de história, anuários, legislação e ementas. O referencial teórico é pautado nos pressupostos da Teoria Histórico-Cultural, que se constitui científica, mas também política (MOURA, 2017; VYGOTSKI, 1995; CEDRO, 2008; OLIVEIRA, 2002; ZANELLA, 2007), mediante o estudo do movimento lógico-histórico – apregoado por Kopnin, 1978; Sousa, Panossian, Cedro, 2014; Sousa, 2004; Fazenda, 2000 – de constituição da disciplina de Álgebra Linear (PIRES, 2006; DORIER, 2000, SILVA, 2003; MOORE, 1995). Fez-se necessário compreender o que motivou a sua inserção no contexto universitário e qual a sua contribuição para a formação do professor de Matemática, com base em Bastos (1980; 2006), Boyer (1974), Cavalari (2012), Celestino (2000), Garding (1981), Kopnin (1978), Caraça (1959), Ríbnikov (1987), Tubino (1984), Kleiner (2007), entre outros. Foram analisadas 55 Universidades Federais Brasileiras que oferecem o curso presencial de Licenciatura em Matemática. Estabeleceram-se como categorias de análise os conteúdos das ementas, a carga horária e a referência bibliográfica básica da disciplina obrigatória de Álgebra Linear oferecida nestas instituições. Como principais conclusões, observou-se que a disciplina de Álgebra Linear começou a ser desenvolvida e ensinada nas Universidades para resolver problemas práticos de diversos intelectuais das engenharias e ciências correlatas, e que o repasse de seus conteúdos de forma desvinculada pode contribuir para as dificuldades do processo de ensino e aprendizagem presentes nessa disciplina.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-12-22T14:29:13Z No. of bitstreams: 1 cristhianoandregamaranoduartecarneirosilva.pdf: 577501 bytes, checksum: 1d4ac19d80966a6129b9b190ed9b7eec (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-02-07T13:10:11Z (GMT) No. of bitstreams: 1 cristhianoandregamaranoduartecarneirosilva.pdf: 577501 bytes, checksum: 1d4ac19d80966a6129b9b190ed9b7eec (MD5) / Made available in DSpace on 2017-02-07T13:10:12Z (GMT). No. of bitstreams: 1 cristhianoandregamaranoduartecarneirosilva.pdf: 577501 bytes, checksum: 1d4ac19d80966a6129b9b190ed9b7eec (MD5) Previous issue date: 2013-02-19 / Deixado de lado durante anos na Mecânica Quântica, o Emaranhamento é visto hoje em dia como uma fonte, um recurso a ser utilizado. Cabendo a cada pesquisador aproveita-lo da melhor forma possível. Usado para gerar algoritmos mais eficientes, teleportar estados quânticos, e realizar tarefas antes impossíveis, o emaranhamento pode ser um recurso ainda mais estranho. Basta ver o fenômeno da catálise, onde o emaranhamento extra utilizado não é consumido. Aqui nosso objetivo é estudar um pouco mais sobre a catálise em sistemas quânticos e obter uma maneira de dizer quais estados são catalisadores em potencial. / Left aside for years in quantum theory, the entanglement is today a source, a resource to be utilised. Each researcher should use it of the best way possible. Used to generate faster algorithms, to teleport states and perform tasks before impossibles, the entanglement may be a more strange source. Just watch the catalysis phenomenon, where the extra entanglement utilized is not consumed. Here our goal is studying just a little bit of catalysis in quantum systems and get a way to say which states are potential catalysts.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-02-23T11:38:46Z No. of bitstreams: 1 vitorrezendealmeida.pdf: 2575210 bytes, checksum: 8e4561af05356d6156cc876779826bb9 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-02-26T14:42:32Z (GMT) No. of bitstreams: 1 vitorrezendealmeida.pdf: 2575210 bytes, checksum: 8e4561af05356d6156cc876779826bb9 (MD5) / Made available in DSpace on 2016-02-26T14:42:32Z (GMT). No. of bitstreams: 1 vitorrezendealmeida.pdf: 2575210 bytes, checksum: 8e4561af05356d6156cc876779826bb9 (MD5) Previous issue date: 2013-11-14 / Neste trabalho investigamos quais são as características que deve possuir a disciplina Álgebra Linear para que ela seja considerada um Curso de Serviço para uma Licenciatura em Matemática. Caracterizamos esta pesquisa pelo desenvolvimento de uma abordagem qualitativa de investigação, na qual realizamos uma leitura de entrevistas com alunos de uma Pós-Graduação em Educação Matemática, projetamos, executamos e analisamos um Seminário de Álgebra Linear com alunos de uma Licenciatura em Matemática. A leitura da produção de significados de todos envolvidos nesta pesquisa foi desenvolvida tomando como referencial o Modelo dos Campos Semânticos. O produto educacional, elaborado a partir dessa investigação, é uma proposta de ensino do conteúdo transformação linear direcionada para a formação matemática de estudantes da Licenciatura em Matemática, entendendo a disciplina Álgebra Linear como um Curso de Serviço. / In this work, we investigate which characteristics the discipline Linear Algebra must have to be considered a Service Course for a Major in Mathematics. We characterize this research by developing a qualitative research approach in which we put into practice a reading of interviews with students of a Graduate course in Mathematics Education, and besides, we developed, put into practice and analyzed a Seminary on Linear Algebra with students of a Mathematics course. The reading of the meanings produced by all involved in this research was developed taking as a reference the Model of Semantic Fields. The educational product, drawn from this research, is a proposal for teaching in linear transformation directed to students in Mathematics who are preparing themselves to be teachers, understanding the discipline Linear Algebra as a Service-Course.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-04-11T15:37:22Z No. of bitstreams: 1 arethafontesalves.pdf: 3205656 bytes, checksum: 5fc98b7b40ec8618513671e0d6085944 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-04-24T03:36:16Z (GMT) No. of bitstreams: 1 arethafontesalves.pdf: 3205656 bytes, checksum: 5fc98b7b40ec8618513671e0d6085944 (MD5) / Made available in DSpace on 2016-04-24T03:36:16Z (GMT). No. of bitstreams: 1 arethafontesalves.pdf: 3205656 bytes, checksum: 5fc98b7b40ec8618513671e0d6085944 (MD5) Previous issue date: 2013-11-08 / O presente trabalho tem como objetivo levantar as características de um Curso de Serviço de Álgebra Linear voltado a alunos de Licenciatura em Matemática. Para tanto, desenvolvemos uma análise segundo o Modelo dos Campos Semânticos e uma revisão de literatura, voltada para três temas que permeiam nosso estudo, são eles: a Produção de Significados para a Álgebra Linear; a noção de Curso de Serviço e; a Formação Matemática do Professor de Matemática. Esta análise possibilitou que nos preparássemos para realizar uma pesquisa de campo que se constituiu em um seminário de Álgebra Linear com o intuito de estruturar quais seriam estas características. / This work aims to raise the characteristics of a Service Course in Linear Algebra for students of Mathematics. For that, we develop an analysis according to the Model of Semantic Fields and a literature review focused on three themes that permeate our study, they are: Production of meanings for Linear Algebra, the notion of Service Course and; the Mathematics Training of mathematics teacher. This analysis allowed us to prepare ourselves to conduct a field research which constituted which was constituted by a seminary in Linear Algebra with the aim of structuring what these characteristics would be.

La résolution de grands systèmes linéaires creux est un élément essentiel des simulations numériques.Ces résolutions peuvent représenter jusqu’à 80% du temps de calcul des simulations.Une parallélisation efficace des noyaux d’algèbre linéaire creuse conduira donc à obtenir de meilleures performances. En mémoire distribuée, la parallélisation de ces noyaux se fait le plus souvent en modifiant leschéma numérique. Par contre, en mémoire partagée, un parallélisme plus efficace peut être utilisé. Il est doncimportant d’utiliser deux niveaux de parallélisme, un premier niveau entre les noeuds d’une grappe de serveuret un deuxième niveau à l’intérieur du noeud. Lors de l’utilisation de méthodes itératives en mémoire partagée,les graphes de tâches permettent de décrire naturellement le parallélisme en prenant comme granularité letravail sur une ligne de la matrice. Malheureusement, cette granularité est trop fine et ne permet pas d’obtenirde bonnes performances à cause du surcoût de l’ordonnanceur de tâches.Dans cette thèse, nous étudions le problème de la granularité pour la parallélisation par graphe detâches. Nous proposons d’augmenter la granularité des tâches de calcul en créant des agrégats de tâchesqui deviendront eux-mêmes des tâches. L’ensemble de ces agrégats et des nouvelles dépendances entre lesagrégats forme un graphe de granularité plus grossière. Ce graphe est ensuite utilisé par un ordonnanceur detâches pour obtenir de meilleurs résultats. Nous utilisons comme exemple la factorisation LU incomplète d’unematrice creuse et nous montrons les améliorations apportées par cette méthode. Puis, dans un second temps,nous nous concentrons sur les machines à architecture NUMA. Dans le cas de l’utilisation d’algorithmeslimités par la bande passante mémoire, il est intéressant de réduire les effets NUMA liés à cette architectureen plaçant soi-même les données. Nous montrons comment prendre en compte ces effets dans un intergiciel àbase de tâches pour ainsi améliorer les performances d’un programme parallèle. / Solving large sparse linear system is an essential part of numerical simulations. These resolve can takeup to 80% of the total of the simulation time.An efficient parallelization of sparse linear kernels leads to better performances. In distributed memory,parallelization of these kernels is often done by changing the numerical scheme. Contrariwise, in sharedmemory, a more efficient parallelism can be used. It’s necessary to use two levels of parallelism, a first onebetween nodes of a cluster and a second inside a node.When using iterative methods in shared memory, task-based programming enables the possibility tonaturally describe the parallelism by using as granularity one line of the matrix for one task. Unfortunately,this granularity is too fine and doesn’t allow to obtain good performance.In this thesis, we study the granularity problem of the task-based parallelization. We offer to increasegrain size of computational tasks by creating aggregates of tasks which will become tasks themself. Thenew coarser task graph is composed by the set of these aggregates and the new dependencies betweenaggregates. Then a task scheduler schedules this new graph to obtain better performance. We use as examplethe Incomplete LU factorization of a sparse matrix and we show some improvements made by this method.Then, we focus on NUMA architecture computer. When we use a memory bandwidth limited algorithm onthis architecture, it is interesting to reduce NUMA effects. We show how to take into account these effects ina task-based runtime in order to improve performance of a parallel program.

Les méthodes formelles ont atteint un degré de maturité conduisant à la conception de systèmes de preuves généralistes, permettant à la fois de vérifier la correction de systèmes logiciels complexes ou de formaliser des mathématiques avancées. Mais souvent, l'accent est mis davantage sur la facilité du raisonnement sur les programmes plutôt que sur leur exécution efficace. L'antagonisme entre ces deux aspects est particulièrement sensible pour les algorithmes de calcul formel, dont la correction repose habituellement sur des concepts mathématiques élaborés, mais dont l'efficacité pratique est une préoccupation importante. Cette thèse développe des approches à l'étude formelle et l'exécution efficace de programmes en théorie des types, et plus précisément dans l'assistant à la preuve \coq{}. Dans un premier temps, nous présentons un environnement d'exécution permettant de compiler en code natif de tels programmes tout en conservant la généralité et l'expressivité du formalisme. Puis, nous nous intéressons aux représentations de données et plus particulièrement au lien formellement vérifié et automatisé entre représentations adaptées aux preuves ou au calcul. Ensuite, nous mettons à profit ces techniques pour l'étude d'algorithmes en algèbre linéaire, comme le produit matriciel de Strassen, le procédé d'élimination de Gauss ou la mise en forme canonique de matrices, dont notamment la forme de Smith pour les matrices sur un anneau euclidien. Enfin, nous ouvrons le champ des applications à la formalisation et au calcul certifié des groupes d'homologie de complexes simpliciaux issus d'images numériques. / Formal methods have reached a degree of maturity leading to the design of general-purpose proof systems, enabling both to verify the correctness of complex software systems and to formalize advanced mathematics. However, the ease of reasoning on programs is often emphasized more than their efficient execution. The antagonism between these two aspects is particularly significant for computer algebra algorithms, whose correctness usually relies on elaborate mathematical concepts, but whose practical efficiency is an important matter of concern. This thesis develops approaches to the formal study and the efficient execution of programs in type theory, and more precisely in the proof assistant \coq{}. In a first part, we introduce a runtime environment enabling the native code compilation of such programs while retaining the generality and expressiveness of the formalism. Then, we focus on data representations and in particular on the formally verified and automatized link between proof-oriented and computation-oriented representations. Then, we take advantage of these techniques to study linear algebra algorithms, like Strassen's matrix product, Gaussian elimination or matrix canonical forms, including the Smith normal form for matrices over a Euclidean ring. Finally, we open the field of applications to the formalization and certified computation of homology groups of simplicial complexes arising from digital images.

Du fait des énormes capacités de calculs des accélérateurs tels que les GPUs et les Xeon Phi, l’utilisation de machines multicoques pourvues d’accélérateurs est devenue commune dans le domaine du calcul haute performance (HPC). La complexité induite par ces accélérateurs a suscité le développement de systèmes d’exécution à base de tâches, dans lesquels les dépendances entre les applications sont exprimées sous la forme de graphe de tâches et où les tâches sont ordonnancées dynamiquement sur les ressources de calcul. La difficulté est alors de concevoir des stratégies d’ordonnancement qui font une utilisation efficace des ressources de calculs et le développement de telles stratégies, même pour un unique noeud hybride, est un enjeu essentiel de la performance des systèmes HPC. Nous considérons dans cette thèse l’ordonnancement de noyaux d’algèbre linéaire dense sur des noeuds complètement hétérogènes et constitués de CPUs et de GPUs. Les performances relatives des accélérateurs par rapport aux coeurs classique dépend très fortement du noyau considéré. Par exemple, les accélérateurs sont beaucoup plus efficaces pour les produits de matrices, par exemple, que pour les factorisations. Dans cette thèse, nous analysons les performances de stratégies statiques et dynamiques d’ordonnancement et nous proposons un ensemble de stratégies intermédiaires, en ajoutant des composantes statiques (respectivement dynamiques) à des stratégies d’ordonnancements dynamique (respectivement statiques). Récemment, une stratégie appelée HeteroPrio a été proposée, qui s’appuie sur les affinités entre les tâches et les ressources pour un petit ensemble de tâches différentes s’exécutant sur deux types de ressources. Nous avons étendu cette stratégie d’ordonnancement pour des graphes de tâches généraux pour deux types de ressources puis pour plus de deux types. De manière complémentaire, nous avons également démontré des facteurs d’approximation et des pires cas pour HeteroPrio dans le cas d’un ensemble de tâches indépendantes sur différents types de plates-formes. / Due to massive computation power of accelerators such as GPU, Xeon phi, multicore machines equipped with accelerators are becoming popular in High Performance Computing (HPC). The added complexity led to the development of different task-based runtime systems, which allow computations to be expressed as graphs of tasks and rely on runtime systems to schedule those tasks among all resources of the platform. The real challenge is to design efficient schedulers for such runtimes to make effective utilization of all resources. Developing good schedulers, even for a single hybrid node, and analyzing them can thus have a strong impact on the performance of current HPC systems. We consider the problem of scheduling dense linear algebra applications on fully hybrid platforms made of CPUs and GPUs. The relative performance of CPU and GPU highly depends on the sub-routine. For instance, GPUs are much more efficient to process matrix-matrix multiplications than matrix factorizations. In this thesis, we analyze the performance of static and dynamic scheduling strategies and we propose a set of intermediate strategies, by adding static (resp. dynamic) features into dynamic (resp. static) strategies. A resource centric dynamic scheduler, HeteroPrio, which is based on affinity between tasks and resources, has been proposed recently for a set of small independent tasks on two types of resources. We extend and analyze this scheduler for general task graphs first on two types of resources and then on more than two types of resources. Additionally, we provide approximation ratios and worst case examples of HeteroPrio for a set of independent tasks on different platform sizes.

Cette thèse traite d’une nouvelle classe de préconditionneurs qui ont pour but d’accélérer la résolution des grands systèmes creux, courant dans les problèmes scientifiques ou industriels, par les méthodes itératives préconditionnées. Pour appliquer ces préconditionneurs, la matrice d’entrée doit être réorganisée avec un algorithme de dissection emboîtée. Nous introduisons également une technique de recouvrement qui s’adapte à l’idée de chevauchement des sous-domaines provenant des méthodes de décomposition de domaine, aux méthodes de dissection emboîtée pour améliorer la convergence de nos préconditionneurs.Les résultats montrent que cette technique de recouvrement nous permet d’améliorer la vitesse de convergence de Nested SSOR (NSSOR) et Nested Modified incomplete LU with Rowsum proprety (NMILUR) qui sont des préconditionneurs que nous étudions. La dernière partie de cette thèse portera sur nos contributions dans le domaine du calcul parallèle. Nous présenterons la distribution des données et les algorithmes parallèles utilisés pour la mise en oeuvre de nos préconditionneurs. Les résultats montrent que sur une grille régulière 400x400x400, le nombre d’itérations nécessaire à la résolution avec un de nos préconditionneurs, Nested Filtering Factorization préconditionneur (NFF), n’augmente que légèrement quand le nombre de sous-domaines augmente jusqu’à 2048. En ce qui concerne les performances d’exécution sur le super-calculateur Curie, il passe à l’échelle jusqu’à 2048 coeurs et il est 2,6 fois plus rapide que le préconditionneur Schwarz Additif Restreint (RAS) qui est un des préconditionneurs basés sur les méthodes de décomposition de domaine implémentés dans la bibliothèque de calcul scientifique PETSc, bien connue de la communauté. / This thesis addresses a new class of preconditioners which aims at accelerating solving large sparse systems arising in scientific and engineering problem by using preconditioned iterative methods. To apply these preconditioners, the input matrix needs to be reordered with K-way nested dissection. We also introduce an overlapping technique that adapts the idea of overlapping subdomains from domain decomposition methods to nested dissection based methods to improve the convergence of these preconditioners. Results show that such overlapping technique improves the convergence rate of Nested SSOR (NSSOR) and Nested Modified Incomplete LU with Rowsum property (NMILUR) precondtioners that we worked on. We also present the data distribution and parallel algorithms for implementing these preconditioners. Results show that on a 400x400x400 regular grid, the number of iterations with Nested Filtering Factorization preconditioner (NFF) increases slightly while increasing the number of subdomains up to 2048. In terms of runtime performance on Curie supercomputer, it scales up to 2048 cores and it is 2.6 times faster than the domain decomposition preconditioner Restricted Additive Schwarz (RAS) as implemented in PETSc.

Singular values have been found to be useful in the theory of unitarily invariant norms, as well as many modern computational algorithms. In examining singular value inequalities, it can be seen how these can be related to eigenvalues and how several algebraic inequalities can be preserved and written in an analogous singular value form. We examine the fundamental building blocks to the modern theory of singular value inequalities, such as positive matrices, matrix norms, block matrices, and singular value decomposition, then use these to examine new techniques being used to prove singular value inequalities, and also look at existing conjectures.

In 2019, Adams, Ehlting, and Edwards developed a four-variable system of ordinary differential equations modelling phenylalanine metabolism in plants according to Michaelis-Menten kinetics. Analysis of the model suggested that when a series of reactions known as the Shikimate Ester Loop (SEL) is included, phenylalanine flux into primary metabolic pathways is prioritized over flux into secondary metabolic pathways when the availability of shikimate, a phenylalanine precursor, is low. Adams et al. called this mechanism of metabolic regulation the Precursor Shutoff Valve (PSV). Here, we attempt to simplify Adams and colleagues’ model by reducing the system to three variables and replacing the Michaelis-Menten terms with piecewise-defined approximations we call ramp functions. We examine equilibria and stability in this simplified model, and show that PSV-type regulation is still present in the version with the SEL. Then, we define a class of systems structurally similar to the simplified Adams model called biochemical ramp systems. We study the properties of the Jacobian matrices of these systems and then explore equilibria and stability in systems of n ≥ 2 variables. Finally, we make several suggestions regarding future work on biochemical ramp systems. / Graduate