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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.
91

Números primos: uma fórmula geradora

Moura, Frederico Torres de 04 July 2018 (has links)
O trabalho aqui apresentado tem por objetivo fazer uma investigação sobre os números primos e algumas de suas características e propriedades, dentre elas uma fórmula geradora de números primos. Para isto foram realizadas pesquisas bibliográficas e assim introduzidos conceitos de aritmética bem como teoremas e suas respectivas demonstrações com intuito de esclarecimento acerca do assunto abordado. No contexto do programa este trabalho é direcionado ao professor regente, como uma forma de aprimorar seus conhecimentos, para estudantes em nível de olimpíada ou mesmo para alunos de nível médio que tenham interesse no assunto em questão. Nesse sentido, foi desenvolvido um questionário contendo perguntas básicas sobre os números primos e aplicado para os estudantes que compõe a terceira série do Colégio Iesgo, na cidade de Formosa-GO, afim de identificar o que se conhece sobre os números primos no ensino básico. / The work presented here aims to investigate the prime numbers and some of their characteristics and properties, among them a formula generating prime numbers. For this purpose, bibliographical researches were carried out, thus introducing concepts of arithmetic as well as theorems and their respective demonstrations in order to clarify the subject matter. In the context of the program this work is directed to the regent teacher, as a way to improve his knowledge, for students at the level of the Olympiad or even for students of medium level who have an interest in the subject in question. In this sense, a questionnaire containing basic questions about primes was developed and applied to the students who make up the third series of the Iesgo College, in the city of Formosa-GO, in order to identify what is known about prime numbers in elementary education.
92

Existência e concentração de soluções para sistemas elípticos com condição de Neumann / Existence and concentration of solutions to elliptic systems with Neumann boundary conditions.

Pimenta, Marcos Tadeu de Oliveira 13 March 2008 (has links)
Estudamos uma classe de sistemas elípticos - \'elipson POT 2\' \'DELTA\' u + u = g(v) em \'ÔMEGA\' - \'elipson POT 2\' \'DELTA\' v + v f(u) em ÔMEGA \' PARTIAL\'u SOBRE \'PARTIAL n = \'PARTIAL v SOBRE PARTIAL n = O sobre \"PARTIAL\'\' ÔMEGA\' onde \' ÔMEGA ESTA CONTIDO EM R POT. N\' é um domínio limitado, com bordo regular e N \' > ou =\' 3. As não linearidades f e g são funções com crescimento superlinear e subcrítico no infinito. Estudamos resultados sobre a existência de uma sequência de soluções que se concentram, quando o parâmetro \'epsilon\' tende a zero, em um ponto da fronteira que maximiza a sua curvatura. Para isso utilizamos um resultado abstrato sobre existência de pontos críticos para funcionais fortemente indefinidos / We study an singularly perturbed Hamiltonean elliptic system - \'elipson POT 2\' \'DELTA\' u + u = g(v) in \'ÔMEGA\' - \'elipson POT 2\' \'DELTA\' v + v f(u) in ÔMEGA \' PARTIAL\'u ON \'PARTIAL n = \'PARTIAL v ON PARTIAL n\' = O sobre \"PARTIAL\'\' ÔMEGA\' when \'ÔMEGA THIS CONTAINED R POT. N\' is a smooth bounded domain, N \' > or =\' 3 and f and g are nonlinearities having superlinear and subcritical growth at infinity. We study an abstract result about existence of critical points of strongly as \' epsilon\' goes to zero, at a point of the boundary which maximizes the mean curvature of the boundary
93

On the differential Grothendieck-Riemann-Roch theorems

Ho, Man-Ho January 2012 (has links)
Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / We investigate aspects of differential K-theory. In particular, we give a direct proof that the Freed-Lott differential analytic index is well defined, and a short proof of the differential Grothendieck-Riemann-Roch theorem in the setting of Freed-Lott differential K-theory. We also construct explicit ring isomorphisms between Freed-Lott differential K-theory and Simons-Sullivan differential K-theory, define the Simons-Sullivan differential analytic index, and prove the differential Grothendieck-Riemann-Roch theorem in the setting of Simons-Sullivan differential K-theory. / 2031-01-02
94

O objeto matemático triângulo em teoremas de Regiomontanus: um estudo de suas demonstrações mediado pelo Geogebra

Mod , Luiz Felipe Araujo 12 December 2016 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2017-01-16T16:06:13Z No. of bitstreams: 1 Luiz Felipe Araujo Mod.pdf: 2213635 bytes, checksum: ed88b2864c3ad5d9ff5133afef48da91 (MD5) / Made available in DSpace on 2017-01-16T16:06:13Z (GMT). No. of bitstreams: 1 Luiz Felipe Araujo Mod.pdf: 2213635 bytes, checksum: ed88b2864c3ad5d9ff5133afef48da91 (MD5) Previous issue date: 2016-12-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Abstract: This Master’s research aims to investigate Regiomontanus’ theorems about triangles with the use of the software GeoGebra. Regiomontanus (1436-1476) was a mathematician whose production contributed especially in the development of trigonometry with the work De Triangulis Omnimodis Libri Quinque, published in 1533 and that is the focus of this research. In the Book I of his work, there are theorems whose demonstrations involve constructions of triangles met some given conditions. Demonstrations of some of these theorems are analyzed by the mediation of the dynamic movements of GeoGebra in view of the functions of the demonstration according to Villiers. There is the need to scroll through the different roles of the demonstration and the importance of the use of GeoGebra as an instrument of investigation, in which it is possible to identify that some possibilities are not included in the Regiomontanus’ demonstrations. The survey, in its development, also indicates possibilities of how a legacy of the History of Mathematics can become a research activity in the classroom / Resumo: Esta pesquisa de Mestrado Acadêmico tem como objetivo investigar teoremas de Regiomontanus, sobre triângulos, com a utilização do software GeoGebra. Regiomontanus (1436-1476) foi um matemático cuja produção contribuiu especialmente no desenvolvimento da Trigonometria, com a obra De Triangulis Omnimodis Libri Quinque, publicado em 1533 e que é o foco desta pesquisa. No Livro I dessa obra, encontram-se teoremas cujas demonstrações envolvem construções de triângulos satisfeitas algumas condições dadas. As demonstrações de alguns destes teoremas são analisadas pela mediação dos movimentos dinâmicos do GeoGebra na perspectiva das funções da demonstração segundo Villiers. Verifica-se a necessidade de percorrer os diferentes papéis da demonstração e a importância da utilização do GeoGebra como instrumento de investigação, no qual é possível identificar que algumas possibilidades não estão contempladas nas demonstrações de Regiomontanus. A pesquisa, em seu desenvolvimento, também indica possibilidades de como um legado da História da Matemática pode-se tornar uma atividade de investigação em sala de aula
95

Strukturální teorie grafových imerzí / Structural Theory of Graph Immersions

Hruška, Michal January 2019 (has links)
Immersion is a notion of graph inclusion related to the notion of graph minors. While the structural theory of graph minors is extensive, there are still numerous open problems in the structural theory of graph immersions. Kuratowski's theorem claims that the class of graphs that do not contain a subdivision of the graphs K3,3 and K5 is exactly the class of planar graphs. The main goal of this thesis is to describe the structure of the graphs that do not contain an immersion of K3,3. Such graphs can be separated by small edge cuts into small graphs or planar 3-regular graphs. 1
96

Modular forms and converse theorems for Dirichlet series

Karlsson, Jonas January 2009 (has links)
<p>This thesis makes a survey of converse theorems for Dirichlet series. A converse theo-rem gives sufficient conditions for a Dirichlet series to be the Dirichlet series attachedto a modular form. Such Dirichlet series have special properties, such as a functionalequation and an Euler product. Sometimes these properties characterize the modularform completely, i.e. they are sufficient to prove the proper transformation behaviourunder some discrete group. The problem dates back to Hecke and Weil, and has morerecently been treated by Conrey et.al. The articles surveyed are:</p><ul><li>"An extension of Hecke's converse theorem", by B. Conrey and D. Farmer</li><li>"Converse theorems assuming a partial Euler product", by D. Farmer and K.Wilson</li><li>"A converse theorem for ¡0(13)", by B. Conrey, D. Farmer, B. Odgers and N.Snaith</li></ul><p>The results and the proofs are described. The second article is found to contain anerror. Finally an alternative proof strategy is proposed.</p>
97

Modular forms and converse theorems for Dirichlet series

Karlsson, Jonas January 2009 (has links)
This thesis makes a survey of converse theorems for Dirichlet series. A converse theo-rem gives sufficient conditions for a Dirichlet series to be the Dirichlet series attachedto a modular form. Such Dirichlet series have special properties, such as a functionalequation and an Euler product. Sometimes these properties characterize the modularform completely, i.e. they are sufficient to prove the proper transformation behaviourunder some discrete group. The problem dates back to Hecke and Weil, and has morerecently been treated by Conrey et.al. The articles surveyed are: "An extension of Hecke's converse theorem", by B. Conrey and D. Farmer "Converse theorems assuming a partial Euler product", by D. Farmer and K.Wilson "A converse theorem for ¡0(13)", by B. Conrey, D. Farmer, B. Odgers and N.Snaith The results and the proofs are described. The second article is found to contain anerror. Finally an alternative proof strategy is proposed.
98

Regularity and Nearness Theorems for Families of Local Lie Groups

January 2011 (has links)
In this work, we prove three types of results with the strategy that, together, the author believes these should imply the local version of Hilbert's Fifth problem. In a separate development, we construct a nontrivial topology for rings of map germs on Euclidean spaces. First, we develop a framework for the theory of (local) nonstandard Lie groups and within that framework prove a nonstandard result that implies that a family of local Lie groups that converge in a pointwise sense must then differentiability converge, up to coordinate change, to an analytic local Lie group, see corollary 6.3.1. The second result essentially says that a pair of mappings that almost satisfy the properties defining a local Lie group must have a local Lie group nearby, see proposition 7.2.1. Pairing the above two results, we get the principal standard consequence of the above work which can be roughly described as follows. If we have pointwise equicontinuous family of mapping pairs (potential local Euclidean topological group structures), pointwise approximating a (possibly differentiably unbounded) family of differentiable (sufficiently approximate) almost groups, then the original family has, after appropriate coordinate change, a local Lie group as a limit point. (See corollary 7.2.1 for the exact statement.) The third set of results give nonstandard renditions of equicontinuity criteria for families of differentiable functions, see theorem 9.1.1. These results are critical in the proofs of the principal results of this paper as well as the standard interpretations of the main results here. Following this material, we have a long chapter constructing a Hausdorff topology on the ring of real valued map germs on Euclidean space. This topology has good properties with respect to convergence and composition. See the detailed introduction to this chapter for the motivation and description of this topology.
99

Computational applications of invariance principles

Meka, Raghu Vardhan Reddy 14 August 2015 (has links)
This thesis focuses on applications of classical tools from probability theory and convex analysis such as limit theorems to problems in theoretical computer science, specifically to pseudorandomness and learning theory. At first look, limit theorems, pseudorandomness and learning theory appear to be disparate subjects. However, as it has now become apparent, there's a strong connection between these questions through a third more abstract question: what do random objects look like. This connection is best illustrated by the study of the spectrum of Boolean functions which directly or indirectly played an important role in a plethora of results in complexity theory. The current thesis aims to take this program further by drawing on a variety of fundamental tools, both classical and new, in probability theory and analytic geometry. Our research contributions broadly fall into three categories. Probability Theory: The central limit theorem is one of the most important results in all of probability and richly studied topic. Motivated by questions in pseudorandomness and learning theory we obtain two new limit theorems or invariance principles. The proofs of these new results in probability, of interest on their own, have a computer science flavor and fall under the niche category of techniques from theoretical computer science with applications in pure mathematics. Pseudorandomness: Derandomizing natural complexity classes is a fundamental problem in complexity theory, with several applications outside complexity theory. Our work addresses such derandomization questions for natural and basic geometric concept classes such as halfspaces, polynomial threshold functions (PTFs) and polytopes. We develop a reasonably generic framework for obtaining pseudorandom generators (PRGs) from invariance principles and suitably apply the framework to old and new invariance principles to obtain the best known PRGs for these complexity classes. Learning Theory: Learning theory aims to understand what functions can be learned efficiently from examples. As developed in the seminal work of Linial, Mansour and Nisan (1994) and strengthened by several follow-up works, we now know strong connections between learning a class of functions and how sensitive to noise, as quantified by average sensitivity and noise sensitivity, the functions are. Besides their applications in learning, bounding the average and noise sensitivity has applications in hardness of approximation, voting theory, quantum computing and more. Here we address the question of bounding the sensitivity of polynomial threshold functions and intersections of halfspaces and obtain the best known results for these concept classes.
100

Maksimumų vidurkių analizė / Analysis of maxima means

Kasperavičiūtė, Lina 11 August 2008 (has links)
Darbe nagrinėjami nepriklausomų ir vienodai pasiskirsčiusių atsitiktinių dydžių maksimumai su skirstinio funkcija F. Skaičiuojami maksimumų vidurkiai Pareto ir Buro skirstinių atveju, palyginami su tiksliomis reikšmėmis ir žinomu įverčiu. Kai imties didumas n yra didelis, naudojamos ribinės teoremos, Pareto skirstinio atveju randamas konvergavimo greičio įvertis. Taip pat skaičiuojami Buro atsitiktinių dydžių maksimumų vidurkiai, kai imties didumas N yra pasiskirstęs pagal geometrinį skirstinį. / In this work maxima of independent and identically distributed random variables with distribution function F are analyzed. We calculate maxima means for Pareto and Buro distributions and compare theoretical values with known estimates. We use limit theorems for maxima means when the set size n is large and find the estimate of convergence rate for Pareto random variables. When the set size N is geometric random number maxima means for Buro random variables are calculated.

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