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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.
31

Combinatorial Argument of Partition with Point, Line, and Space / 點線面與空間分割的組合論證法

王佑欣, Yuhsin Wang Unknown Date (has links)
在這篇論文裡,我們將要討論一類古典的問題,這類問題已經經由許多方法解決,例如:遞迴關係式、差分方程式、尤拉公式等等。接著我們歸納低維度的特性,並藉由定義出一組方程式-標準n維空間分割系統-來推廣這些特性到一般的$n$維度空間中。然後我們利用演算法來提供一個更直接的組合論證法。最後,我們會把問題再細分成有界區域與無界區域的個數。 / In this article, we will discuss a class of classical questions had been solved by Recurrence Relation, Difference Equation, and Euler's Formula, etc.. And then, we construct a system of equations -Standard Partition System of n-Dimensional Space- to generalize the properties of maximizing the number of regions made up by k partitioner in an n-dimensional space and look into the construction of each dimension. Also, we provide a more directly Combinatorial Argument by Algorithm for this kind of question. At last, we focus on the number of bounded regions and unbounded regions in sense of maximizing the number of regions.
32

Poliedros Regulares no Ensino Médio

Silva, Hércules do Nascimento 29 August 2014 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2016-03-28T12:29:14Z No. of bitstreams: 1 arquivototal.pdf: 800250 bytes, checksum: 42e76ab05ea580b4fd24a3312b9b4212 (MD5) / Made available in DSpace on 2016-03-28T12:29:14Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 800250 bytes, checksum: 42e76ab05ea580b4fd24a3312b9b4212 (MD5) Previous issue date: 2014-08-29 / In this work we present a study of the regular polyhedra, comparing and discussing the concepts and de nitions given in the study of regular polyhedra in textbooks most widely used in Brazilian high schools. We prove the theorem of Euler, we calculate surface areas and volumes of regular polyhedra. Finally, we present some mathematical software that can be used by students and mathematics teachers in the spatial geometry classes as auxiliary material in the teaching and learning of this subject in the classroom. / Neste trabalho apresentamos um estudo sobre os poliedros regulares, comparando e discutindo os conceitos e as de nições que são dadas no estudo dos poliedros regulares nos livros didáticos mais utilizados nas escolas brasileiras de Ensino Médio. Provamos o teorema de Euler, calculamos áreas de superfícies e os volumes dos poliedros regulares. Por m, apresentamos alguns softwares matemáticos que podem ser utilizados pelos alunos e professores de Matemática nas aulas de geometria espacial como material auxiliar no processo de ensino e aprendizagem deste tema em sala de aula.
33

A característica de Euler

Justino, Gildeci José 24 September 2013 (has links)
Submitted by Clebson Anjos (clebson.leandro54@gmail.com) on 2015-05-18T18:12:57Z No. of bitstreams: 1 arquivototal.pdf: 13930019 bytes, checksum: d5e52fb67904848f89fafaf5ec93c06d (MD5) / Approved for entry into archive by Clebson Anjos (clebson.leandro54@gmail.com) on 2015-05-18T18:15:19Z (GMT) No. of bitstreams: 1 arquivototal.pdf: 13930019 bytes, checksum: d5e52fb67904848f89fafaf5ec93c06d (MD5) / Made available in DSpace on 2015-05-18T18:15:19Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 13930019 bytes, checksum: d5e52fb67904848f89fafaf5ec93c06d (MD5) Previous issue date: 2013-09-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This dissertation is focused on the Euler's theorem for polyhedra homeomorphic to the sphere. Present statements made by Cauchy, Poincaré and Legendre. As a consequence we show that there are only ve regular convex polyhedra, called polyhedra Plato. / Esta dissertação tem como tema central o Teorema de Euler para poliedros homeomorfos à esfera. Apresentamos demonstrações feitas por Cauchy, Poincaré e Legendre. Como consequência mostramos a existência de apenas cinco poliedros convexos regulares, os chamados poliedros de Platão.
34

Použití běžného odstředivého čerpadla jako turbíny / Use of standard centrifugal pump as turbine

Podešva, Adam January 2021 (has links)
This work deals with the use of a centrifugal pump in turbine mode and control of the system where this machine is operated. The introduction describes and divides the various types of pumps and discusses the issue of Euler's pump and turbine equations. The flow control options are also described here. Part of the work is a research that examines the advantages and disadvantages of using a centrifugal pump in turbine mode, the possibilities of using this system and real applications in the Czech Republic and in the world. The main part is the design of a mathematical model in Microsoft Excel, which solves the regulation of the piping system with a pump operating in turbine mode, especially out of the optimal operating parameters.
35

Dinâmica de vórtices em superfícies com aplicações ao problema de dois vórtices no toro plano / Vortex dynamics on surfaces with applications to the problem of two vortices in a flat torus

Humberto Henrique de Barros Viglioni 15 May 2013 (has links)
Este trabalho apresenta uma dedução das equações para a dinâmica de vórtices em superfícies utilizando argumentos físicos e balanço de momento, obtendo o resultado já conhecido devido a Boatto/Koiller e Hally. Na primeira parte, elaboramos uma releitura da contribuição de diversos pesquisadores incluindo, além dos já citados, o trabalho de Marchioro e Pulvirenti sobre a propriedade de localização para a equação de Euler e também a importante contribuição de Flucher e Gustafsson no que diz respeito à determinação da função de Green e função de Robin hidrodinâmicas em domínios do plano. Na segunda parte revisamos o problema da dinâmica de um traçador passivo induzida por um vórtice no disco unitário e estendemos para o caso com vorticidade de fundo constante. Por fim, analisamos a dinâmica de dois vórtices no toro plano, a qual reduz-se ao estudo da dinâmica do centro de vorticidade com hamiltoniana dada pela função de Green. É feita uma descrição das bifurcações das curvas de níveis desta hamiltoniana com respeito a variações do parâmetro modular. Mostramos que o campo hamiltoniano em questão é preservado por biholomorfismos e, portanto, o espaço dos parâmetros pode ser reduzido ao espaço de Moduli do toro plano. Mudanças dentro de uma mesma classe de equivalência por biholomorfismos podem alterar apenas a classe de homotopia das curvas de nível. / In this thesis the equations for the motion of vortices on Riemannian surfaces is studied. Using conservation of momentum and physical arguments, the classical equations of Hally and Boatto/Koiller are recovered. Then the localization result for the Euler\'s equation with flat metric (Marchioro and Pulvirenti) and the determination of the Green\'s and Robin\'s functions on plane domains are revisited in the context of Riemannian surfaces. On a second part of the thesis two examples are analyzed. At first the dynamics of a passive tracer in the unit disk on the flat plane with constant background vorticity. At second the dynamics of two vortices on flat tori. This last system is integrable. The dynamics is determined by the level sets of the Green\'s function which depends on the modular parameter of the torus. The full bifurcation diagram of the system as a function of the module parameter is determined.
36

Dinâmica de vórtices em superfícies com aplicações ao problema de dois vórtices no toro plano / Vortex dynamics on surfaces with applications to the problem of two vortices in a flat torus

Viglioni, Humberto Henrique de Barros 15 May 2013 (has links)
Este trabalho apresenta uma dedução das equações para a dinâmica de vórtices em superfícies utilizando argumentos físicos e balanço de momento, obtendo o resultado já conhecido devido a Boatto/Koiller e Hally. Na primeira parte, elaboramos uma releitura da contribuição de diversos pesquisadores incluindo, além dos já citados, o trabalho de Marchioro e Pulvirenti sobre a propriedade de localização para a equação de Euler e também a importante contribuição de Flucher e Gustafsson no que diz respeito à determinação da função de Green e função de Robin hidrodinâmicas em domínios do plano. Na segunda parte revisamos o problema da dinâmica de um traçador passivo induzida por um vórtice no disco unitário e estendemos para o caso com vorticidade de fundo constante. Por fim, analisamos a dinâmica de dois vórtices no toro plano, a qual reduz-se ao estudo da dinâmica do centro de vorticidade com hamiltoniana dada pela função de Green. É feita uma descrição das bifurcações das curvas de níveis desta hamiltoniana com respeito a variações do parâmetro modular. Mostramos que o campo hamiltoniano em questão é preservado por biholomorfismos e, portanto, o espaço dos parâmetros pode ser reduzido ao espaço de Moduli do toro plano. Mudanças dentro de uma mesma classe de equivalência por biholomorfismos podem alterar apenas a classe de homotopia das curvas de nível. / In this thesis the equations for the motion of vortices on Riemannian surfaces is studied. Using conservation of momentum and physical arguments, the classical equations of Hally and Boatto/Koiller are recovered. Then the localization result for the Euler\'s equation with flat metric (Marchioro and Pulvirenti) and the determination of the Green\'s and Robin\'s functions on plane domains are revisited in the context of Riemannian surfaces. On a second part of the thesis two examples are analyzed. At first the dynamics of a passive tracer in the unit disk on the flat plane with constant background vorticity. At second the dynamics of two vortices on flat tori. This last system is integrable. The dynamics is determined by the level sets of the Green\'s function which depends on the modular parameter of the torus. The full bifurcation diagram of the system as a function of the module parameter is determined.
37

Études combinatoires du tableau d’Euler sur les produits en couronne / Combinatorial studies of Euler's table on wreath products

Faliharimalala, Hilarion 31 March 2010 (has links)
Au cours des deux dernières décennies, des travaux actifs ont été menés pour étendre des résultats classiques liés au groupe symétrique à d'autres groupes plus généraux. Cette thèse a pour objectif d’étendre aux produits en couronne les résultats concernant le tableau de différence d’Euler. Elle est divisée en cinq chapitres. Le tableau de différence d’Euler lié à la suite {n!} conduit naturellement à la formule du nombre de dérangements. Nous étudions dans les deux premiers chapitres, le tableau de différence d’Euler associé à la suite {rnn!} et la généralisation du problème de dérangements. Pour les coefficients de ce dernier tableau, nous donnons des interprétations combinatoires en termes de k-successions sur les produits en couronne. Clarke et al. ont introduit un q-analogue du tableau de différence d’Euler sur le groupe symétrique. Dans le troisième chapitre, nous étendons leurs résultats sur les produits en couronne. En généralisant leur bijection, nous montrons que « (fix, exc, fmaj) » et « (fix, exc, fmaf) » sont équidistribués sur les produits en couronne où «fmaf» est une nouvelle statistique mahonienne. D’autre part, Foata et Han ont récemment construit deux transformations. Nous prouvons dans le quatrième chapitre que ses bijections fournissent une factorisation de la bijection de Clarke et al.. Dans le cinquième chapitre nous donnons une extension de la seconde transformation fondamentale de Foata sur les mots r-colorés. Nous prouvons l’équidistribution sur les produits en couronne de « (fmaj , des*) » et « (finv , col) » où « col » est la somme des couleurs et « des* » une nouvelle statistique. / In the last two decades, much effort has been made to extend various enumerative results on symmetric groups to other more general groups. The main objective of this thesis is to extend to wreath products the results that concern the Euler's difference table. It is divided into five chapters. Euler's difference table associated to the sequence {n!} leads naturally to the counting formula for the derangements. In the first two chapters, we study Euler's difference table associated to the sequence {rnn!} and the generalized derangement problem. For the coefficients appearing in the later table, we give the combinatorial interpretations in terms of k-successions on wreath products. Clarke et al. introduced a q-analogue of Euler's difference table on symmetric group. In the third chapter, we extend their results to wreath products. By generalizing their bijection, we prove the equidistribution of the triple statistics “(fix, exc, fmaj)” and “(fix, exc, fmaf)” on wreath products, where “fmaf” is a new mahonian statistic on wreath products. On the other hand, Foata and Han have recently constructed two new transformations. We prove in fourth chapter that their two bijections provide a factorization of Clarke et al.'s bijection. In the fifth chapter we give an extension of Foata’s second fundamental transformation on r-colored words. We show that the bistatistics “(fmaj , des*)” and “(finv , col)” are equidistributed on wreath products, where “col” is the sum of color and “des*” a new statistic.
38

Eulerovo číslo v matematické analýze / Euler's number in calculus

RÁLKOVÁ, Lucie January 2017 (has links)
The main aim of my thesis on the topic of "Euler's number in mathematical analysis" is to create an overview of the Euler numbers in calculus. This essay in the first part deals with the rise of the number e, in other parts of the current use of calculus. Purpose of this work is the insight students of secondary schools and universities to problems Euler numbers and to better understand the importance of e not only in mathematics.
39

Simulation du bruit d'écoulements anisothermes par méthodes hybrides pour de faibles nombres de Mach / Noise computation of non isothermal flows by hybrid methods for low Mach numbers

Nana, Cyril 20 September 2012 (has links)
Cette étude porte sur le calcul numérique du champ acoustique rayonné par des écoulements subsoniques turbulents présentant des inhomogénéités de température. Des méthodes hybrides sont développées grâce à un développement de Janzen-Rayleigh des équations de Navier-Stokes. L'écoulement est résolu par un calcul quasi incompressible puis les perturbations acoustiques sont propagées selon deux méthodes : les équations d'Euler linéarisées (EEL) et l'approximation à faible nombre de Mach perturbée(PLMNA). Les méthodes sont validées sur des cas simples puis appliquées à une couche de mélange isotherme et anisotherme en développement spatial. / This study focuses on the numerical calculation of the acoustic field radiated by subsonic turbulent flows with temperature inhomogeneities. Hybrid methods are developed through a Rayleigh-Janzen expansion of the Navier-Stokes equations. The flow is solved in a quasi-incompressible way then the acoustic disturbances are propagated by two methods : the linearized Euler's equations (EEL) and the perturbed low Mach number approximation (PLMNA). The methods are validated on simple cases and then applied to an isothermal and non isothermal spatially evolving mixing layer.
40

Platonská a Archimédovská tělesa a jejich vlastnosti ve výuce matematiky na středních školách / Platonic and Archimedean solids and their properties in teaching of mathematics at secondary schools

Dohnalová, Eva January 2016 (has links)
Title: Platonic and Archimedean solids and their properties in teaching of mathematics at secondary schools Author: Eva Dohnalová Department: Department of Didactics of Mathematics Supervisor: doc. RNDr. Jarmila Robová, CSc. Abstract: This work is an extension of my bachelor work and it is intended for all people interested in regular and semiregular polyhedra geometry. It is a comprehensive text which summarizes brief history, description and classification of regular and semiregular polyhedra. The work contains proofs of Descartes' and Euler's theorems and proofs about number of regular and semiregular polyhedra. It can be also used as a didactic aid in the instruction of regular and semiregular solids at secondary schools. This text is supplemented by illustrative pictures made in GeoGebra and Cabri3D. Keywords: Regular polyhedra, platonic solids, Platon, semiregular polyhedra, Archimedean solids, Archimedes, dulaism, Descartes' theorem, Euler's theorem.

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