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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

Conjunto de Mandelbrot / Mandelbrot set

Reis, Márcio Vaiz dos 29 August 2016 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-10-03T21:11:40Z No. of bitstreams: 2 Dissertação - Márcio Vaiz dos Reis - 2016.pdf: 2097960 bytes, checksum: 296b1790b8c8fe50c0e91d2d5ee204c4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-10-04T10:46:49Z (GMT) No. of bitstreams: 2 Dissertação - Márcio Vaiz dos Reis - 2016.pdf: 2097960 bytes, checksum: 296b1790b8c8fe50c0e91d2d5ee204c4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-10-04T10:46:49Z (GMT). No. of bitstreams: 2 Dissertação - Márcio Vaiz dos Reis - 2016.pdf: 2097960 bytes, checksum: 296b1790b8c8fe50c0e91d2d5ee204c4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-08-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The purpose of this dissertation is to present an introductory approach to the complex dynamics and fractal geometry, especially the Mandelbrot set. With the goal to simplify and stimulate the introduction of complex number in high school, the approach adopted was: the definition of the Mandelbrot set and its characteristics; the relationship between the Mandelbrot set and Julia set; how to find by using the Mandelbrot set. One of the tools used to help the teaching was Geogeobra, a dynamic software that allows the student to build the Mandelbrot set. Through this study, it is expected to motivate the learning of complex numbers by using fractal obtained by the study of function ( ) . Obtaining, as a result, a differentiated and motivating way of learning for a better understanding and intellectual development of the students. / Esse trabalho apresenta uma abordagem introdutória para a dinâmica complexa e a geometria fractal, em especial o conjunto de Mandelbrot. Com objetivo de facilitar e motivar a interação dos alunos com o ensino dos números complexos, a abordagem adotada foi: a definição do conjunto de Mandelbrot e suas características; a relação entre o conjunto de Mandelbrot e o conjunto de Julia; a relação do conjunto de Mandelbrot e o número . Uma das ferramentas utilizadas para auxiliar o professor foi o Geogeobra, um software dinâmico que permite o aluno a construção do conjunto de Mandelbrot. Por meio deste trabalho, espera-se motivar o ensino dos números complexos através do fractal obtido pelo estudo da função ( ) . Obtendo assim, como resultado, uma forma diferenciada e motivadora do aprendizado do aluno, garantindo um melhor entendimento e desenvolvimento intelectual.
32

Hausdorff Dimension of Shrinking-Target Sets Under Non-Autonomous Systems

Lopez, Marco Antonio 08 1900 (has links)
For a dynamical system on a metric space a shrinking-target set consists of those points whose orbit hit a given ball of shrinking radius infinitely often. Historically such sets originate in Diophantine approximation, in which case they describe the set of well-approximable numbers. One aspect of such sets that is often studied is their Hausdorff dimension. We will show that an analogue of Bowen's dimension formula holds for such sets when they are generated by conformal non-autonomous iterated function systems satisfying some natural assumptions.
33

A commutative noncommutative fractal geometry

Samuel, Anthony January 2010 (has links)
In this thesis examples of spectral triples, which represent fractal sets, are examined and new insights into their noncommutative geometries are obtained. Firstly, starting with Connes' spectral triple for a non-empty compact totally disconnected subset E of {R} with no isolated points, we develop a noncommutative coarse multifractal formalism. Specifically, we show how multifractal properties of a measure supported on E can be expressed in terms of a spectral triple and the Dixmier trace of certain operators. If E satisfies a given porosity condition, then we prove that the coarse multifractal box-counting dimension can be recovered. We show that for a self-similar measure μ, given by an iterated function system S defined on a compact subset of {R} satisfying the strong separation condition, our noncommutative coarse multifractal formalism gives rise to a noncommutative integral which recovers the self-similar multifractal measure ν associated to μ, and we establish a relationship between the noncommutative volume of such a noncommutative integral and the measure theoretical entropy of ν with respect to S. Secondly, motivated by the results of Antonescu-Ivan and Christensen, we construct a family of (1, +)-summable spectral triples for a one-sided topologically exact subshift of finite type (∑{{A}} {{N}}, σ). These spectral triples are constructed using equilibrium measures obtained from the Perron-Frobenius-Ruelle operator, whose potential function is non-arithemetic and Hölder continuous. We show that the Connes' pseudo-metric, given by any one of these spectral triples, is a metric and that the metric topology agrees with the weak*-topology on the state space {S}(C(∑{{A}} {{N}}); {C}). For each equilibrium measure ν[subscript(φ)] we show that the noncommuative volume of the associated spectral triple is equal to the reciprocal of the measure theoretical entropy of ν[subscript(φ)] with respect to the left shift σ (where it is assumed, without loss of generality, that the pressure of the potential function is equal to zero). We also show that the measure ν[subscript(φ)] can be fully recovered from the noncommutative integration theory.
34

Directed graph iterated function systems

Boore, Graeme C. January 2011 (has links)
This thesis concerns an active research area within fractal geometry. In the first part, in Chapters 2 and 3, for directed graph iterated function systems (IFSs) defined on ℝ, we prove that a class of 2-vertex directed graph IFSs have attractors that cannot be the attractors of standard (1-vertex directed graph) IFSs, with or without separation conditions. We also calculate their exact Hausdorff measure. Thus we are able to identify a new class of attractors for which the exact Hausdorff measure is known. We give a constructive algorithm for calculating the set of gap lengths of any attractor as a finite union of cosets of finitely generated semigroups of positive real numbers. The generators of these semigroups are contracting similarity ratios of simple cycles in the directed graph. The algorithm works for any IFS defined on ℝ with no limit on the number of vertices in the directed graph, provided a separation condition holds. The second part, in Chapter 4, applies to directed graph IFSs defined on ℝⁿ . We obtain an explicit calculable value for the power law behaviour as r → 0⁺ , of the qth packing moment of μ[subscript(u)], the self-similar measure at a vertex u, for the non-lattice case, with a corresponding limit for the lattice case. We do this (i) for any q ∈ ℝ if the strong separation condition holds, (ii) for q ≥ 0 if the weaker open set condition holds and a specified non-negative matrix associated with the system is irreducible. In the non-lattice case this enables the rate of convergence of the packing L[superscript(q)]-spectrum of μ[subscript(u)] to be determined. We also show, for (ii) but allowing q ∈ ℝ, that the upper multifractal q box-dimension with respect to μ[subscript(u)], of the set consisting of all the intersections of the components of F[subscript(u)], is strictly less than the multifractal q Hausdorff dimension with respect to μ[subscript(u)] of F[subscript(u)].
35

Intercomunicação entre matemática-ciência-arte:um estudo sobre as implicações das geometrias na produção artistica desde o gótico até o surrealismo / Intercomunicação entre matemática-ciência-arte:um estudo sobre as implicações das geometrias na produção artistica desde o gótico até o surrealismo

Lyra, Wilton Luiz Duque 31 July 2008 (has links)
Podemos dizer que as Catedrais Góticas, verdadeiras bíblias de pedra, são signos medievais que podem ser lidos já como o resultado da intercomunicação entre matemática-ciência-arte, uma vez que tais edificações surgiram de projeções arquitetônicas, da utilização de uma dada geometria assim como da execução de determinados conjuntos escultóricos. Podemos ainda ressaltar que essa intercomunicação se intensifica durante todo o Renascimento, exemplo máximo da união entre esses três campos do conhecimento. No Renascimento, a geometria dominante e a Euclidiana; os artistas enfrentavam as questões espaciais a partir de um ponto de vista fixo. A historia se transforma quando alguns matemáticos por volta de 1800 começam a pensar na possibilidade de outra geometria que não a de Euclides. Surge, então, um tipo de geometria que ficaria conhecida como geometria não-Euclidiana, uma geometria para ser utilizada em espaços curvos. As implicações dessa nova Geometria foram tão abrangentes que influiu na elaboração da Teoria da Relatividade, de Einstein. Um novo tipo de intercomunicação entre matemática-ciência-arte, que ajudou a resolver questões ligadas a quadrimensionalidade. Enfim, trata-se de uma intercomunicação que influenciou na produção de artistas como Picasso, Duchamp e Dali. / We can say that the Gothic Cathedral, veritable Bibles of stone, are medieval sign that can be read as a result of the intercommunication among mathematicsscience- art, since that one buildings appear from an architectonic projection, from the utilization of a given geometry just as from the execution of a group of sculpture. We can salient that this intercommunication intensifies during Renaissance, example maximum of the union among those three fields of knowledge. Into the Renaissance, the geometry dominant is the Euclidean, the artists faced the special questions from one fixed viewpoint. The story becomes different when some mathematicians around 1800 begin thinking on the possibility of another geometry that doesn\'t that of Euclids. Appears, then, a kind of geometry that would be known as non-Euclidean Geometry: a geometry to be used in curved space. The implications of that new Geometry was so in-depth that influenced the elaboration of Einsteins Relativity Theory. Therefore a new kind of intercommunication among mathematics-science-art, which it helped to resolve questions linked together to the fourth dimension. An intercommunication that influenced the production of artists like Picasso, Duchamp and Dali.
36

Processamento de sinais e reconhecimento de padrões de resposta de sensores de gases através da geometria fractal. / Signal processing and pattern recognition of gas sensors response by fractal geometry.

Juliano dos Santos Gonschorowski 29 March 2007 (has links)
O objetivo do presente trabalho foi propor métodos de processamento de sinais e reconhecimento de padrões dos sinais de respostas de sensores de gás, utilizando técnicas e modelos da geometria fractal. Foram analisados e estudados os sinais de resposta de dois tipos de sensores. O primeiro sensor foi um dispositivo de óxido de estanho, cujo princípio de funcionamento baseia-se na mudança da resistividade do filme. Este forneceu sinais de respostas com características ruidosas como resposta à interação com as moléculas de gás. O segundo sensor foi um dispositivo Metal-Óxido-Semicondutor (MOS) com princípio de funcionamento baseado na geração de foto corrente, fornecendo respostas imagens bidimensionais. Para as análises dos sinais ruidosos do sensor de óxido de estanho, foi proposto um método de processamento baseado no modelo do movimento Browniano fracionário. Com este método foi possível a discriminação de gases combustíveis com uma taxa de acerto igual a 100%. Para as análises das respostas do tipo imagem do sensor MOS, foram propostos dois diferentes métodos. O primeiro foi embasado no princípio de compressão fractal de imagens e o segundo método proposto, foi baseado na análise e determinação da dimensão fractal multiescala. Ambos os métodos propostos mostram-se eficazes para a determinação da assinatura, como o reconhecimento, de todos os gases que foram utilizados nos experimentos. Os resultados obtidos no presente trabalho abrem novas fronteiras e perspectivas nos paradigmas de processamento de sinais e reconhecimento de padrões, quando utilizada a teoria da geometria fractal. / The aim of the present work was to propose methods for signal possessing and pattern, recognition from the signals response of gas sensors using models and techniques from the fractal geometry. The data studied and analyzed were obtained from two kinds of sensors. The first sensor was the tin oxide device, which detection principle is based on the resistivity changes of the tin oxide film and it provides noisy signals as response to the gas interaction. The second sensor was a metal-oxide-semiconductor (MOS) device, which has as the working principle the photocurrent generation. This sensor provides two-dimensional images signals. A method using a fractional Brownian motion was proposed to analyze the noise signal from the tin oxide device. The fuel gases discrimination employing this model was 100% successful. Two different methods were proposed to analyze the signal response from the MOS device. The first method was based on the fractal image compression technique and the second one was based on the analysis and determination of the multiscale fractal dimension. Both proposed methods have shown to be efficient tools for signature determination as the pattern recognition of all gases that were used in the experiment. The results obtained in the present work open new frontiers and perspectives inside the paradigms of the signal processing and pattern recognition by using the fractal theory.
37

Fractais: generalização de padrões no ensino fundamental

Mineli, Juliano de Paula 15 June 2012 (has links)
Made available in DSpace on 2016-04-27T16:57:17Z (GMT). No. of bitstreams: 1 Juliano de Paula Mineli.pdf: 2480017 bytes, checksum: e6777d50d1d15cbae78249914a247c2f (MD5) Previous issue date: 2012-06-15 / This research aimed to study the formation of skills of elementary school students to solve problems, or more specifically, problems whose solutions can be expressed by 1st order equations. My teaching experience has made me raise a hypothesis that the difficulties that students encountered in the organization of the equation, related to the situations of Generalization of Patterns. From then define the objectives of this research is to: investigate problems related to skills training for the Generalization of Patterns and teaching situations to facilitate the training. For data collection, drafted a sequence containing three Curriculum Activities supported on the elements of Fractal Geometry, with a view to generalization of Standards and their implementation based on the Theory of Didactic Situations of Brousseau - theoretical framework used in this research.This sequence was applied in seven sessions to a class of 7th grade (6th grade) of a private Institution located in the city of Ribeirão Preto.This is a qualitative research study using a methodology supported by the Didactic Engineering. The observations and analyzes showed that: the characteristics of fractal figures provide pattern recognition, pattern recognition encourages students to make generalization, the use of geometric shapes provides better organization of data from a mathematical problem, which favors their resolution; generalization of a given situation helps the development of algebraic thinking as well as their attitudes and autonomy in order to observe, raising conjectures, draw conclusions and justify their answers / Esta pesquisa objetivou estudar formação de habilidades de estudantes do Ensino Fundamental para resolver problemas, ou mais especificamente problemas cujas soluções podem ser expressas por equações do 1º grau. Minha experiência docente me fez levantar uma hipótese de que as dificuldades que os estudantes encontravam, na organização da equação, relacionavam-se à situações de Generalização de Padrões. A partir daí definimos os objetivos desta pesquisa que são: investigar dificuldades relacionadas à formação de habilidades para a Generalização de Padrões e de situações de ensino facilitadoras para essa formação. Para a coleta de dados, elaborei uma Sequência Didática contendo três Atividades apoiadas nos elementos da Geometria Fractal, tendo em vista a Generalização de Padrões e sua aplicação baseada na Teoria das Situações Didáticas de Brousseau referenciais teóricos utilizados nesta pesquisa. Essa Sequência foi aplicada em sete sessões a uma turma do 7° ano (6ª série) de uma instituição privada situada na cidade de Ribeirão Preto. Trata-se de uma pesquisa de caráter qualitativo com metodologia apoiada na Engenharia Didática. Como conclusão podemos apontar que: as características das figuras fractais propiciam o reconhecimento de padrões; o reconhecimento de padrões favorece ao aluno realizar generalização; a utilização de figuras geométricas propicia melhor organização dos dados de um problema matemático, o que favorece sua resolução; a generalização de uma dada situação auxilia o desenvolvimento do pensamento algébrico, bem como suas atitudes e autonomia no sentido de observar, levantar conjecturas, tirar conclusões e justificar suas respostas
38

Processamento de sinais e reconhecimento de padrões de resposta de sensores de gases através da geometria fractal. / Signal processing and pattern recognition of gas sensors response by fractal geometry.

Gonschorowski, Juliano dos Santos 29 March 2007 (has links)
O objetivo do presente trabalho foi propor métodos de processamento de sinais e reconhecimento de padrões dos sinais de respostas de sensores de gás, utilizando técnicas e modelos da geometria fractal. Foram analisados e estudados os sinais de resposta de dois tipos de sensores. O primeiro sensor foi um dispositivo de óxido de estanho, cujo princípio de funcionamento baseia-se na mudança da resistividade do filme. Este forneceu sinais de respostas com características ruidosas como resposta à interação com as moléculas de gás. O segundo sensor foi um dispositivo Metal-Óxido-Semicondutor (MOS) com princípio de funcionamento baseado na geração de foto corrente, fornecendo respostas imagens bidimensionais. Para as análises dos sinais ruidosos do sensor de óxido de estanho, foi proposto um método de processamento baseado no modelo do movimento Browniano fracionário. Com este método foi possível a discriminação de gases combustíveis com uma taxa de acerto igual a 100%. Para as análises das respostas do tipo imagem do sensor MOS, foram propostos dois diferentes métodos. O primeiro foi embasado no princípio de compressão fractal de imagens e o segundo método proposto, foi baseado na análise e determinação da dimensão fractal multiescala. Ambos os métodos propostos mostram-se eficazes para a determinação da assinatura, como o reconhecimento, de todos os gases que foram utilizados nos experimentos. Os resultados obtidos no presente trabalho abrem novas fronteiras e perspectivas nos paradigmas de processamento de sinais e reconhecimento de padrões, quando utilizada a teoria da geometria fractal. / The aim of the present work was to propose methods for signal possessing and pattern, recognition from the signals response of gas sensors using models and techniques from the fractal geometry. The data studied and analyzed were obtained from two kinds of sensors. The first sensor was the tin oxide device, which detection principle is based on the resistivity changes of the tin oxide film and it provides noisy signals as response to the gas interaction. The second sensor was a metal-oxide-semiconductor (MOS) device, which has as the working principle the photocurrent generation. This sensor provides two-dimensional images signals. A method using a fractional Brownian motion was proposed to analyze the noise signal from the tin oxide device. The fuel gases discrimination employing this model was 100% successful. Two different methods were proposed to analyze the signal response from the MOS device. The first method was based on the fractal image compression technique and the second one was based on the analysis and determination of the multiscale fractal dimension. Both proposed methods have shown to be efficient tools for signature determination as the pattern recognition of all gases that were used in the experiment. The results obtained in the present work open new frontiers and perspectives inside the paradigms of the signal processing and pattern recognition by using the fractal theory.
39

The Dynamics of Semigroups of Contraction Similarities on the Plane

Stefano Silvestri (6983546) 16 October 2019 (has links)
<div>Given a parametrized family of Iterated Function System (IFS) we give sufficient conditions for a parameter on the boundary of the connectedness locus, M, to be accessible from the complement of M.</div><div>Moreover, we provide a few examples of such parameters and describe how they are connected to Misiurewicz parameter in the Mandelbrot set, i.e. the connectedness locus of the quadratic family z^2+c.<br></div>
40

Geometria fractal

Iwai, Marceli Megumi Hamazi January 2015 (has links)
Orientador: Prof. Dr. Daniel Miranda Machado / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Mestrado Profissional em Matemática em Rede Nacional, 2015.

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