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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

The Euler Line in non-Euclidean geometry

Strzheletska, Elena 01 January 2003 (has links)
The main purpose of this thesis is to explore the conditions of the existence and properties of the Euler line of a triangle in the hyperbolic plane. Poincaré's conformal disk model and Hermitian matrices were used in the analysis.ʹ
32

Minimum complexity principle for knowledge transfer in artificial learning / Principe de minimum de complexité pour le transfert de connaissances en apprentissage artificiel

Murena, Pierre-Alexandre 14 December 2018 (has links)
Les méthodes classiques d'apprentissage automatique reposent souvent sur une hypothèse simple mais restrictive: les données du passé et du présent sont générées selon une même distribution. Cette hypothèse permet de développer directement des garanties théoriques sur la précision de l'apprentissage. Cependant, elle n'est pas réaliste dans un grand nombre de domaines applicatifs qui ont émergé au cours des dernières années.Dans cette thèse, nous nous intéressons à quatre problèmes différents en intelligence artificielle, unis par un point commun: tous impliquent un transfer de connaissance d'un domaine vers un autre. Le premier problème est le raisonnement par analogie et s'intéresse à des assertions de la forme "A est à B ce que C est à D". Le second est l'apprentissage par transfert et se concentre sur des problèmes de classification dans des contextes où les données d'entraînement et de test ne sont pas de même distribution (ou n'appartiennent même pas au même espace). Le troisième est l'apprentissage sur flux de données, qui prend en compte des données apparaissant continument une à une à haute fréquence, avec des changements de distribution. Le dernier est le clustering collaboratif et consiste à faire échanger de l'information entre algorithmes de clusterings pour améliorer la qualité de leurs prédictions.La principale contribution de cette thèse est un cadre général pour traiter les problèmes de transfer. Ce cadre s'appuie sur la notion de complexité de Kolmogorov, qui mesure l'information continue dans un objet. Cet outil est particulièrement adapté au problème de transfert, du fait qu'il ne repose pas sur la notion de probabilité tout en étant capable de modéliser les changements de distributions.En plus de cet effort de modélisation, nous proposons dans cette thèse diverses discussions sur d'autres aspects ou applications de ces problèmes. Ces discussions s'articulent autour de la possibilité de transfert dans différents domaines et peuvent s'appuyer sur d'autres outils que la complexité. / Classical learning methods are often based on a simple but restrictive assumption: The present and future data are generated according to the same distributions. This hypothesis is particularly convenient when it comes to developing theoretical guarantees that the learning is accurate. However, it is not realistic from the point of view of applicative domains that have emerged in the last years.In this thesis, we focus on four distinct problems in artificial intelligence, that have mainly one common point: All of them imply knowledge transfer from one domain to the other. The first problem is analogical reasoning and concerns statements of the form "A is to B as C is to D". The second one is transfer learning and involves classification problem in situations where the training data and test data do not have the same distribution (nor even belong to the same space). The third one is data stream mining, ie. managing data that arrive one by one in a continuous and high-frequency stream with changes in the distributions. The last one is collaborative clustering and focuses on exchange of information between clustering algorithms to improve the quality of their predictions.The main contribution of this thesis is to present a general framework to deal with these transfer problems. This framework is based on the notion of Kolmogorov complexity, which measures the inner information of an object. This tool is particularly adapted to the problem of transfer, since it does not rely on probability distributions while being able to model the changes in the distributions.Apart from this modeling effort, we propose, in this thesis, various discussions on aspects and applications of the different problems of interest. These discussions all concern the possibility of transfer in multiple domains and are not based on complexity only.
33

O ensino das geometrias não-euclidianas: um olhar sob a perspectiva da divulgação científica / Teaching non-euclidean geometries: a view from the perspective of scientific popularization

Ribeiro, Renato Douglas Gomes Lorenzetto 14 September 2012 (has links)
Este trabalho investiga as possibilidades de ensino de ideias fundamentais das geometrias não-euclidianas sob a perspectiva da Divulgação Científica e identifica as principais características presentes nas pesquisas que relatam experiências de ensino destas geometrias. nas pesquisas que relatam experiências de ensino destas geometrias. Bibliográfica, a pesquisa fundamenta teoricamente a Divulgação Científica, a educação nãoformal e o ensino das geometrias não-euclidianas. Em relação às geometrias, enfatizou-se o processo histórico de seu surgimento, em especial as tentativas de prova do quinto postulado de Euclides, pois esse processo evidencia uma quebra de paradigma no conhecimento matemático, incluindo a concepção de verdade matemática. Sobre o ensino das geometrias, debateu-se sua inserção no currículo da educação básica e o crescente número de menções ao tema em orientações educacionais oficiais, tanto no Brasil como no exterior. Procurou-se compreender os objetivos dos educadores que se propõem a ensinar as geometrias nãoeuclidianas e percebeu-se que tais objetivos não se vinculam unicamente ao pressuposto de que a aprendizagem da geometria euclidiana se torna significativa quando se proporciona o contato com as não-euclidianas. Foi feito um mapeamento de algumas pesquisas que apresentam experiências de ensino das geometrias e elencaram-se seus êxitos. A análise das pesquisas que relatam estudos de caso esteve focada nos recursos normalmente utilizados, nos principais pressupostos e nos públicos escolhidos. Nessas pesquisas, percebeu-se forte presença da geometria esférica e da geometria hiperbólica, abordadas principalmente por intermédio de materiais concretos e de software de geometria dinâmica, respectivamente. Ficou evidenciada a possibilidade de ensino de ideias fundamentais das geometrias nãoeuclidianas para diferentes públicos. / This paper investigates the teaching possibilities of fundamental ideas of the non- Euclidean geometries under the perspective of scientific popularization and identifies the main characteristics in the teaching of these geometries. This bibliographical research justifies scientific theory, non-formal education, and the teaching of non-Euclidean geometries. In relation to various geometries, we have emphasized the historical process of its emergence, in particular attempts to prove Euclid\'s fifth postulate since this process shows a paradigm in mathematical knowledge, including the concept of mathematical truth. On the teaching of geometry, we have discussed its inclusion in the curriculum of basic education and the growing number of references to the subject in official educational guidelines, both in Brazil and abroad. We have tried to understand the goals of educators who purport to teach non- Euclidean geometries and realized that these goals do not connect solely to the assumption that learning of Euclidean geometry becomes significant when it provides the contact with non-Euclidean geometries. We have mapped some of the studies with teaching experiences of geometries and listed their successes. The analysis of the research that reports case studies focused on the resources normally used, on the main assumptions, and on chosen audiences. In the analyzed research, we have encountered a strong presence of Spherical Geometry and Hyperbolic Geometry, mainly approached via concrete materials and dynamic geometry pieces of software, respectively. The teaching possibility of basic principles of the non- Euclidean geometries for different publics became evident.
34

A produção matemática em um ambiente virtual de aprendizagem : o caso da geometria euclidiana espacial /

Santos, Silvana Claudia. January 2006 (has links)
Orientador: Marcelo de Carvalho Borba / Banca: Siobhan Victoria Healy / Banca: Marcus Vinicius Maltempi / Resumo: Neste trabalho investigo como se dá a produção matemática de alunos-professores em um curso de extensão universitária à distância sobre "Tendências em Educação Matemática". As interações entre os participantes aconteceram, em geral, por meio de encontros semanais síncronos e a distância, nos quais eram discutidas questões relacionadas a algumas das tendências em Educação Matemática e sobre o desenvolvimento de atividades de geometria euclidiana espacial, sendo que este último tema consiste no foco de estudo desta pesquisa. Para as construções geométricas sugeri o uso do software gratuito Wingeom, contudo, outros recursos como materiais manipulativos, bem como diferentes estratégias de resolução foram observadas. Essa dinâmica evidenciou a coordenação de diferentes mídias durante o processo investigativo, que exigiu dos participantes grande envolvimento e empatia para melhor compreender a explicação apresentada durante a discussão no chat. A sala de batepapo do TelEduc, ambiente utilizado, apresentou algumas limitações com relação à troca do fazer matemática, contudo, isso não impediu que a discussão acontecesse e que a produção matemática se consolidasse de um modo muito particular. Analisei os dados baseando-me no construto teórico seres-humanos-com-mídias de Borba e Villarreal (2005) e nas idéias de Lévy (1993, 1999, 2003) no que se refere ao pensamento coletivo e à inteligência coletiva. Os resultados obtidos indicaram que as mídias (lápis e papel, materiais manipulativos, Wingeom, Internet e suas diferentes interfaces) em um ambiente virtual de aprendizagem, condicionaram a forma que os participantes discutiram as conjecturas formuladas durante as construções geométricas e transformaram a produção matemática. / Abstract: In this study, I investigate how teacher-students produce mathematics in a university extension distance course entitled “Trends in Mathematics Education”. The interactions between participants generally occurred in weekly synchronous on-line sessions in which issues were discussed related to some of the current trends in mathematics as well as development of spatial Euclidean geometry, the latter being the focus of this study. I suggested the use of the free software Wingeom for the geometrical constructions, but other resources, such as manipulatives, as well as different strategies for problem solving were observed. This dynamic showed evidence of the coordination of different media during the inquiry process, which demanded considerable involvement and empathy on the part of the participants to better understand the explanation presented during the on-line chat discussions. The chat room of TelEuc, the environment used, presented some limitations with respect to the exchange of mathematical activity; nevertheless, this did not impede the discussion nor prevent the mathematical production from consolidating in a very specific way. I based the data analysis on Borba and Villarreal’s (2005) theoretical construct humans-with-media and the ideas of Lévy (1993, 1999, 2003) regarding collective thinking and collective intelligence. The results suggest that the different media (paper-and-pencil, manipulatives, Wingeom, and the Internet with its various interfaces) in a virtual learning environment conditioned the way the participants discussed the conjectures formulated during the geometric constructions and transformed the production of mathematics. / Mestre
35

O uso do geoGebra como ferramenta auxiliar na compreens?o de resultados de geometria pouco explorados no ensino b?sico / The use of geoGebra as auxiliary tool in understanding results of geometry underexplored in basic school

Ferreira, Cassio Marins 28 August 2015 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-01-25T10:55:06Z No. of bitstreams: 1 2015 - Cassio Marins Ferreira.pdf: 2336646 bytes, checksum: ec3b1734c73a206999579144e063ab1f (MD5) / Made available in DSpace on 2017-01-25T10:55:06Z (GMT). No. of bitstreams: 1 2015 - Cassio Marins Ferreira.pdf: 2336646 bytes, checksum: ec3b1734c73a206999579144e063ab1f (MD5) Previous issue date: 2015-08-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This work intends to present the Dynamic Geometry software GeoGebra to elementary school students. It uses the GeoGebra as a tool for building a step by step procedure to convince students of the veracity of results that have simple statements, but not trivial proofs. The following theorems were worked: Morley's Theorem, Hipparchus Theorem, Stewart's Theorem, Menelaus Theorem and 9-Point Circle Theorem. Demonstrations are held strictly in the traditional way, and in parallel it is used the GeoGebra software, thus giving a playful view of the statements. It is understood that this approach will be more attractive, enabling a better understanding of the theorems by students. The work culminates with the application of a motivational test to a class of basic education after a class in which they worked the 9-Point Circle using GeoGebra / Este trabalho tem a inten??o de apresentar o softwarede Geometria Din?micaGeoGebra ao aluno do Ensino B?sico. Utiliza-se o GeoGebra como ferramenta para a constru??o din?mica de um passo-a-passo para convencer os alunos da veracidade de resultados que possuem enunciados simples, mas demonstra??es n?o triviais. Foram trabalhados os seguintes teoremas: Teorema de Morley, Teorema de Hiparco, Teorema de Stewart, Teorema de Menelau e Teorema do C?rculo de 9 Pontos. As demonstra??es s?o realizadas rigorosamente, da forma tradicional, e em paralelo ? feito o uso do softwareGeoGebra, dando assim uma vis?o l?dica das demonstra??es. Entende-se que esta abordagem ser? mais atrativa, possibilitando uma melhor compreens?o dos teoremas pelos alunos. O trabalho culmina com a aplica??o de um teste motivacional a uma turma do Ensino B?sico ap?s uma aula em que se trabalhou o Teorema do C?rculo dos 9 Pontos utilizando-se o GeoGebra
36

O uso de tecnologias como ferramenta de apoio às aulas de geometria

Kitaoka, Alessandra de Carvalho 16 August 2013 (has links)
Made available in DSpace on 2016-06-02T20:29:23Z (GMT). No. of bitstreams: 1 5405.pdf: 3455845 bytes, checksum: 749a1a7ca8b7d3b9399b8de99a655175 (MD5) Previous issue date: 2013-08-16 / Financiadora de Estudos e Projetos / This project's main goal is propose the application of a Teaching Sequence about how finding the notable points of a triangle, in particular, the circumcenter. Introducing in the sequence geometric objects primaries of Euclidean geometry with the axioms and the theorems necessary to construct the circumcenter. The geometric objects will be built through educational software Geogebra. The teaching of geometry, often present to the end of the textbook, is faced with the difficulty of the students to manipulate instruments as ruler, protractor and compass. On the other hand, the fascination of students by computers facilitates the use of geometric softwares. The sum of these factors, have inspired this project. Based on the methodology of the didactic engineering I intend to show the construction steps of mathematical knowing from the student's research experimenting, visualizing, conjecturing, generalizing even demonstrating the mathematical basement in this context. / O presente trabalho objetiva relatar a aplicação de uma Sequência Didática sobre como encontrar os pontos notáveis de um triângulo, em particular o circuncentro, apresento na sequência entes geométricos primários da geometria euclidiana plana junto aos axiomas e teoremas necessários para a construção do circuncentro. Os objetos geométricos serão construídos através do software educacional Geogebra. O ensino da geometria, muitas vezes relegado ao final do livro didático, se depara com a dificuldade que os alunos têm em manipular instrumentos como régua, transferidor e compasso. Por outro lado, o fascínio dos estudantes por computadores facilita a utilização de softwares da Geometria dinâmica. A soma desses fatores, inspirou esse trabalho. Baseado na metodologia da engenharia didática, pretendo mostrar etapas da construção do conhecimento matemático a partir da investigação do aluno, experimentando, visualizando, conjecturando, generalizando e até mesmo demonstrando todo embasamento matemático envolvido nesse contexto.
37

Geometry Aware Compressive Analysis of Human Activities : Application in a Smart Phone Platform

January 2014 (has links)
abstract: Continuous monitoring of sensor data from smart phones to identify human activities and gestures, puts a heavy load on the smart phone's power consumption. In this research study, the non-Euclidean geometry of the rich sensor data obtained from the user's smart phone is utilized to perform compressive analysis and efficient classification of human activities by employing machine learning techniques. We are interested in the generalization of classical tools for signal approximation to newer spaces, such as rotation data, which is best studied in a non-Euclidean setting, and its application to activity analysis. Attributing to the non-linear nature of the rotation data space, which involve a heavy overload on the smart phone's processor and memory as opposed to feature extraction on the Euclidean space, indexing and compaction of the acquired sensor data is performed prior to feature extraction, to reduce CPU overhead and thereby increase the lifetime of the battery with a little loss in recognition accuracy of the activities. The sensor data represented as unit quaternions, is a more intrinsic representation of the orientation of smart phone compared to Euler angles (which suffers from Gimbal lock problem) or the computationally intensive rotation matrices. Classification algorithms are employed to classify these manifold sequences in the non-Euclidean space. By performing customized indexing (using K-means algorithm) of the evolved manifold sequences before feature extraction, considerable energy savings is achieved in terms of smart phone's battery life. / Dissertation/Thesis / M.S. Electrical Engineering 2014
38

O ensino das geometrias não-euclidianas: um olhar sob a perspectiva da divulgação científica / Teaching non-euclidean geometries: a view from the perspective of scientific popularization

Renato Douglas Gomes Lorenzetto Ribeiro 14 September 2012 (has links)
Este trabalho investiga as possibilidades de ensino de ideias fundamentais das geometrias não-euclidianas sob a perspectiva da Divulgação Científica e identifica as principais características presentes nas pesquisas que relatam experiências de ensino destas geometrias. nas pesquisas que relatam experiências de ensino destas geometrias. Bibliográfica, a pesquisa fundamenta teoricamente a Divulgação Científica, a educação nãoformal e o ensino das geometrias não-euclidianas. Em relação às geometrias, enfatizou-se o processo histórico de seu surgimento, em especial as tentativas de prova do quinto postulado de Euclides, pois esse processo evidencia uma quebra de paradigma no conhecimento matemático, incluindo a concepção de verdade matemática. Sobre o ensino das geometrias, debateu-se sua inserção no currículo da educação básica e o crescente número de menções ao tema em orientações educacionais oficiais, tanto no Brasil como no exterior. Procurou-se compreender os objetivos dos educadores que se propõem a ensinar as geometrias nãoeuclidianas e percebeu-se que tais objetivos não se vinculam unicamente ao pressuposto de que a aprendizagem da geometria euclidiana se torna significativa quando se proporciona o contato com as não-euclidianas. Foi feito um mapeamento de algumas pesquisas que apresentam experiências de ensino das geometrias e elencaram-se seus êxitos. A análise das pesquisas que relatam estudos de caso esteve focada nos recursos normalmente utilizados, nos principais pressupostos e nos públicos escolhidos. Nessas pesquisas, percebeu-se forte presença da geometria esférica e da geometria hiperbólica, abordadas principalmente por intermédio de materiais concretos e de software de geometria dinâmica, respectivamente. Ficou evidenciada a possibilidade de ensino de ideias fundamentais das geometrias nãoeuclidianas para diferentes públicos. / This paper investigates the teaching possibilities of fundamental ideas of the non- Euclidean geometries under the perspective of scientific popularization and identifies the main characteristics in the teaching of these geometries. This bibliographical research justifies scientific theory, non-formal education, and the teaching of non-Euclidean geometries. In relation to various geometries, we have emphasized the historical process of its emergence, in particular attempts to prove Euclid\'s fifth postulate since this process shows a paradigm in mathematical knowledge, including the concept of mathematical truth. On the teaching of geometry, we have discussed its inclusion in the curriculum of basic education and the growing number of references to the subject in official educational guidelines, both in Brazil and abroad. We have tried to understand the goals of educators who purport to teach non- Euclidean geometries and realized that these goals do not connect solely to the assumption that learning of Euclidean geometry becomes significant when it provides the contact with non-Euclidean geometries. We have mapped some of the studies with teaching experiences of geometries and listed their successes. The analysis of the research that reports case studies focused on the resources normally used, on the main assumptions, and on chosen audiences. In the analyzed research, we have encountered a strong presence of Spherical Geometry and Hyperbolic Geometry, mainly approached via concrete materials and dynamic geometry pieces of software, respectively. The teaching possibility of basic principles of the non- Euclidean geometries for different publics became evident.
39

Fundamentos da geometria euclidiana para o ensino dos números reais

Figueiredo, Marcelo Cunha 27 February 2014 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-02-22T15:29:17Z No. of bitstreams: 1 marcelocunhafigueiredo.pdf: 1448320 bytes, checksum: d5d065ce34898025ffe848fe7561fe67 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-02-26T14:09:07Z (GMT) No. of bitstreams: 1 marcelocunhafigueiredo.pdf: 1448320 bytes, checksum: d5d065ce34898025ffe848fe7561fe67 (MD5) / Made available in DSpace on 2016-02-26T14:09:07Z (GMT). No. of bitstreams: 1 marcelocunhafigueiredo.pdf: 1448320 bytes, checksum: d5d065ce34898025ffe848fe7561fe67 (MD5) Previous issue date: 2014-02-27 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente trabalho tem por finalidade mostrar uma metodologia de ensino dos números reais com base em fundamentos da Geometria Euclidiana. A régua e o compasso serão instrumentos de grande importância na construção dos conjuntos numéricos. Partindo das imagens geométricas dos números naturais e das operações entre seus elementos, iremos, gradativamente, construindo o conjunto dos números inteiros e dos racionais. Provaremos a existência de números que não são racionais e uma característica desses números que os livros didáticos, em sua maioria, não abordam: a questão da densidade dos conjuntos dos números racionais e irracionais no conjunto dos reais. A geometria euclidiana como suporte nos números reais facilita o entendimento do aluno e traz dinâmica nas operações entre esses números. Apresentamos também uma possibilidade de continuação da proposta de trabalho. / This paper aims to show a teaching methodology of real numbers on the grounds of Euclidean geometry. The ruler and compass are instruments of great importance in the construction of numerical sets. Based on the geometric images of the natural numbers and operations between its elements, we will gradually building the set of integers and rational numbers. We prove the existence of numbers that are not rational and a propertie of those numbers that textbooks mostly do not address: the question of density of the sets of rational and irrational in the set of real numbers. Euclidean geometry as real numbers in support facilitates student understanding and produces dynamic operations between these numbers. We also present a possible continuation of the proposed work.
40

LDPC kódy / LDPC codes

Hrouza, Ondřej January 2012 (has links)
The aim of this thesis are problematics about LDPC codes. There are described metods to create parity check matrix, where are important structured metods using finite geometry: Euclidean geometry and projectice geometry. Next area in this thesis is decoding LDPC codes. There are presented four metods: Hard-Decision algorithm, Bit-Flipping algorithm, The Sum-Product algorithm and Log Likelihood algorithm, where is mainly focused on iterative decoding methods. Practical output of this work is program LDPC codes created in environment Matlab. The program is divided to two parts -- Practise LDPC codes and Simulation LDPC codes. The result reached by program Simulation LDPC codes is used to create a comparison of creating and decoding methods LDPC codes. For comparison of decoding methods LDPC codes were used BER characteristics and time dependence each method on various parameters LDPC code (number of iteration or size of parity matrix).

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