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11	Introduction to differential geometry of plane curves / IntroduÃÃo Ã geometria diferencial das curvas planas Felipe D'Angelo Holanda 24 July 2015 (has links) CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / A intenÃÃo desse trabalho serÃ de abordar de forma bÃsica e introdutÃria o estudo da Geometria Diferencial, que por sua vez tem seus estudos iniciados com as Curvas Planas. SerÃ necessÃrio um conhecimento de CÃlculo Diferencial, Integral e Geometria AnalÃtica para melhor compreensÃo desse trabalho, pois como seu prÃprio nome nos transparece Geometria Diferencial vem de uma junÃÃo do estudo da Geometria envolvendo CÃlculo. Assim abordaremos subtemas como curvas suaves, vetor tangente, comprimento de arco passando por fÃrmulas de Frenet, curvas evolutas e involutas e finalizaremos com alguns teoremas importantes, como o teorema fundamental das curvas planas, teorema de Jordan e o teorema dos quatro vÃrtices. O que, basicamente representa, o capÃtulo 1, 4 e 6 do livro IntroduÃÃo Ãs Curvas Planas de HilÃrio Alencar e Walcy Santos. / The intention of this work is to address in basic form and introductory study of Differential Geometry, which in turn has started his studies with Planas curves. It will require a knowledge of Differential Calculus, Integral and Analytic Geometry for better understanding of this work, because as its name says in Differential Geometry comes from the joint study of geometry involving Calculation. So we discuss sub-themes as smooth curves, tangent vector, arc length through formulas of Frenet, evolutas curves and involute and conclude with some important theorems, as the fundamental theorem of plane curves, Jordan 's theorem and the theorem of four vertices. What basically is, Chapter 1, 4 and 6 of the book Introduction to Plane Curves HilÃrio Alencar and Walcy Santos. fÃrmulas de Frenet teorema fundamental das curvas planas teorema de Jordan Frenet formulas fundamental theorem of plane curves Jordan theorem GEOMETRIA DIFERENCIAL
12	Estimation of geometric properties of three-component signals for condition monitoring / Estimation des propriétés géométriques de signaux à trois composantes pour la surveillance des systèmes Phua, Gailene 07 January 2016 (has links) La plupart des méthodes de surveillance des systèmes sont basées sur l'analyse et la caractérisation de grandeurs physiques qui sont par nature tridimensionnelles. Tracées dans un repère euclidien à trois dimensions, ces grandeurs parcourent en fonction du temps une trajectoire dont les caractéristiques géométriques sont représentatives de l'état du système surveillé. Les techniques classiques de surveillance des systèmes étudient les grandeurs mesurées composante par composante, sans prendre en compte leur nature tridimensionnelle et les propriétés géométriques de leur trajectoire. Une part importante de l'information est ainsi ignorée. Dans le cadre de ce travail de recherche, on se propose de développer une méthode d'analyse et de traitement de grandeurs à trois composantes permettant de mettre en évidence les spécificités géométriques des données et de fournir une information complémentaire pour la surveillance des systèmes. La méthode proposée a été appliquée à deux cas différents : la surveillance des creux de tension des réseaux de puissance triphasés et la surveillance des défauts de roulement des machines électriques tournantes. Dans ces deux cas, les résultats obtenus sont prometteurs et montrent que les indicateurs géométriques estimés mènent à de l'information complémentaire qui peut être utile pour la surveillance des systèmes. / Most methods for condition monitoring are based on the analysis and characterization of physical quantities that are three-dimensional in nature. Plotted in a three-dimensional Euclidean space as a function of time, these quantities follow a trajectory whose geometric characteristics are representative of the state of the monitored system. Usual techniques of condition monitoring study the measured quantities component by component, without taking into account their three-dimensional nature and the geometric properties of their trajectory. A significant part of the information is thus ignored. In this research work, we would therefore like to develop a method for the analysis and processing of three-component quantities capable of highlighting the special geometric features of such data and providing complementary information for condition monitoring. The proposed method has been applied to two different cases: voltage dips monitoring in three-phase power networks and bearing faults monitoring in rotating electrical machines. In this two cases, the results obtained are promising and show that the estimated geometric indicators lead to complementary information that can be useful for condition monitoring. Surveillance des systèmes Grandeurs physiques tridimensionnelles Propriétés géométriques Trajectoire 3D Repère de Frenet Diagnostic des systèmes Condition monitoring Three-Dimensional physical quantities Geometric properties 3D trajectory Frenet frame System diagnosis 620
13	Teoria de curvas para métricas não-euclidianas. Melo, Fábio Silva 08 July 2016 (has links) Dissertação de Mestrado apresentada ao Instituto de Matemática, Estatística e Computação Científica, Unicamp, como requisito parcial para obtenção do título de Mestre em Matemática. 2010 / Submitted by Nilson Junior (nilson.junior@unila.edu.br) on 2016-07-08T20:28:03Z No. of bitstreams: 1 MeloFabioSilva_MP.pdf: 3864560 bytes, checksum: 704d21404c48a187914a0238b121d30e (MD5) / Made available in DSpace on 2016-07-08T21:49:36Z (GMT). No. of bitstreams: 1 MeloFabioSilva_MP.pdf: 3864560 bytes, checksum: 704d21404c48a187914a0238b121d30e (MD5) Previous issue date: 2010 / A teoria local de curvas da Geometria Diferencial no plano e no espaço euclidiano é bem conhecida (vide referências como [4] e [13]). Este trabalho consiste de uma generalização desta teoria usando métricas arbitrárias. Tal generalização é feita substituindo a matriz identidade que define o produto interno usual por outra matriz quadrada, simétrica e positiva definida. Com este novo produto interno, são estudados conceitos como vetor tangente, vetor normal, vetor binormal, fórmulas de Frenet, curvatura e torção Geometria diferencial Produto interno Teoria local de curvas Curvatura Torção Fórmulas de Frenet
14	Pontos Helicoidais e Vértices de Darboux de Curvas no Espaço Euclidiano Machado, Pedro André Pires 11 March 2010 (has links) Secretaria de Ensino Superior / The main aim of this work is a study about twistings points and Darboux vertices of n-space curves. We define the concept of twisting of a n-space curve as flattening point of its tangent indicatrix and show that is equivalent to having higher order of contact with some generalized helix. In the three dimensional case we establish a relation between twisting points and Darboux vertices. We also obtain a version of the four vertex theorem for space closed curves involving such points. / O presente trabalho destina-se a um estudo sobre pontos helicoidais (twistings) e vértices de Darboux de curvas no espaço euclidiano n-dimensional. Pontos helicoidais são pontos de aplainamento (flattening) da indicatriz tangente da curva. Mostramos que nestes pontos a curva tem maior contato com alguma hélice generalizada. No caso de curvas no espaço tridimensional, estabelecemos uma relação entre pontos helicoidais e vértices de Darboux. Obtemos também uma versão do teorema dos quatro vértices para curvas fechadas no espaço envolvendo tais pontos. Matemática, pontos helicoidais Vértice de darboux Matemática euclidiana Esferas Curvas Equações de frenet
15	Geometric approach to multi-scale 3D gesture comparison Ochoa Mayorga, Victor Manuel 11 1900 (has links) The present dissertation develops an invariant framework for 3D gesture comparison studies. 3D gesture comparison without Lagrangian models is challenging not only because of the lack of prediction provided by physics, but also because of a dual geometry representation, spatial dimensionality and non-linearity associated to 3D-kinematics. In 3D spaces, it is difficult to compare curves without an alignment operator since it is likely that discrete curves are not synchronized and do not share a common point in space. One has to assume that each and every single trajectory in the space is unique. The common answer is to assert the similitude between two or more trajectories as estimating an average distance error from the aligned curves, provided that the alignment operator is found. In order to avoid the alignment problem, the method uses differential geometry for position and orientation curves. Differential geometry not only reduces the spatial dimensionality but also achieves view invariance. However, the nonlinear signatures may be unbounded or singular. Yet, it is shown that pattern recognition between intrinsic signatures using correlations is robust for position and orientation alike. A new mapping for orientation sequences is introduced in order to treat quaternion and Euclidean intrinsic signatures alike. The new mapping projects a 4D-hyper-sphere for orientations onto a 3D-Euclidean volume. The projection uses the quaternion invariant distance to map rotation sequences into 3D-Euclidean curves. However, quaternion spaces are sectional discrete spaces. The significance is that continuous rotation functions can be only approximated for small angles. Rotation sequences with large angle variations can only be interpolated in discrete sections. The current dissertation introduces two multi-scale approaches that improve numerical stability and bound the signal energy content of the intrinsic signatures. The first is a multilevel least squares curve fitting method similar to Haar wavelet. The second is a geodesic distance anisotropic kernel filter. The methodology testing is carried out on 3D-gestures for obstetrics training. The study quantitatively assess the process of skill acquisition and transfer of manipulating obstetric forceps gestures. The results show that the multi-scale correlations with intrinsic signatures track and evaluate gesture differences between experts and trainees. 3D gesture comparison Multiscale curvature Curvature-torsion differential geometry complex trajectories quaternion trajectories quaternion projections quaternion metrics 3D trajectory smoothing curvature signature correlations qualitative skill transfer measure medical manipulative gestures nonlinear signatures anisotropic kernel filter curvature numerical stability quaternion smoothing kinematics motor skill transfer curvature signature torsion signature arc-length parameterization tensors Frenet-Serret quaternion framework nonlinear kernel filter geodesic distance finite difference methods differential convolution filter Savitzky-Golay filter least squares curve fitting curvature neighborhood multilevel curvature analysis medical training child bearing simulator robotic simulator motion tracking 3D electromagnetic trackers sequence comparison medical training
16	Geometric approach to multi-scale 3D gesture comparison Ochoa Mayorga, Victor Manuel Unknown Date No description available. 3D gesture comparison Multiscale curvature Curvature-torsion differential geometry complex trajectories quaternion trajectories quaternion projections quaternion metrics 3D trajectory smoothing curvature signature correlations qualitative skill transfer measure medical manipulative gestures nonlinear signatures anisotropic kernel filter curvature numerical stability quaternion smoothing kinematics motor skill transfer curvature signature torsion signature arc-length parameterization tensors Frenet-Serret quaternion framework nonlinear kernel filter geodesic distance finite difference methods differential convolution filter Savitzky-Golay filter least squares curve fitting curvature neighborhood multilevel curvature analysis medical training child bearing simulator robotic simulator motion tracking 3D electromagnetic trackers sequence comparison medical training

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