This thesis addresses a number of problems in computer vision, image processing, and geometry processing, and presents novel solutions to these problems. The overarching theme of the techniques presented here is a multi-scale approach, leveraging mathematical tools to represent images and surfaces at different scales, and methods that can be adapted from one type of domain (eg., the plane) to another (eg., the sphere). The main problem addressed in this thesis is known as stereo reconstruction: reconstructing the geometry of a scene or object from two or more images of that scene. We develop novel algorithms to do this, which work for both planar and spherical images. By developing a novel way to formulate the notion of disparity for spherical images, we are able effectively adapt our algorithms from planar to spherical images. Our stereo reconstruction algorithm is based on a novel application of distance transforms to multi-scale matching. We use matching information aggregated over multiple scales, and enforce consistency between these scales using distance transforms. We then show how multiple spherical disparity maps can be efficiently and robustly fused using visibility and other geometric constraints. We then show how the reconstructed point clouds can be used to synthesize a realistic sequence of novel views, images from points of view not captured in the input images, in real-time. Along the way to this result, we address some related problems. For example, multi-scale features can be detected in spherical images by convolving those images with a filterbank, generating an overcomplete spherical wavelet representation of the image from which the multiscale features can be extracted. Convolution of spherical images is much more efficient in the spherical harmonic domain than in the spatial domain. Thus, we develop a GPU implementation for fast spherical harmonic transforms and frequency domain convolutions of spherical images. This tool can also be used to detect multi-scale features on geometric surfaces. When we have a point cloud of a surface of a particular class of object, whether generated by stereo reconstruction or by some other modality, we can use statistics and machine learning to more robustly estimate the surface. If we have at our disposal a database of surfaces of a particular type of object, such as the human face, we can compute statistics over this database to constrain the possible shape a new surface of this type can take. We show how a statistical spherical wavelet shape prior can be used to efficiently and robustly reconstruct a face shape from noisy point cloud data, including stereo data.

Path tracing is a basic, statistically unbiased method for calculating the global illumination in 3D scenes. For practical purposes, the algorithm is too slow, so it is used mainly for theoretical purposes or as a base for more advanced algorithms. This thesis explores the possibility of improving this algorithm by augmenting the sampling part, which computes outgoing directions during ray traversal through the scene. This optimization is accomplished by creating a special data structure in a preprocess step, which describes approximate light distribution in the scene and which then aids the sampling process. The presented algorithm is implemented in the PBRT library.

This thesis introduces the modern flute techniques used in the solo flute piece Laconisme de l’aile by Kaija Saariaho. The purpose is to find ways to excecute the techniques so that they serve the music in the best way. The techniques are divided in five groups based on how they are excecuted: effects made with the mouth, changing the timbre, multiphonics, effects made by fingers and diffenent sounds by blowing. As an attachment there is a recording of the piece and how the techniques sound in the context. At the end of the process it has been evaluated, if the modern techniques help with the ordinary flute playing as well. / <p>A recording of Laconisme de l'aile by Kaija Saariaho</p>

A tendência crescente na geração de harmônicos nos sistemas elétricos de potência tem ganhado atenção especial no planejamento das redes de transporte de energia elétrica, uma vez que os crescimentos observados acontecem em regiões que antes não representavam qualquer tipo de preocupação. Um dos principais fatores que contribuíram para esse novo contexto é a característica distribuída da geração de harmônicos. Devido a essa nova realidade, métodos mais aprimorados para avaliação de desempenho e modelos mais precisos para a representação de equipamentos tornaram-se necessários. Sendo assim, a pesquisa realizada para a elaboração da presente tese fundamentou a sua investigação em três tópicos com o intuído de fornecer contribuições que permitissem uma avaliação mais precisa das redes elétricas, proporcionando, assim, resultados mais aderentes com a realidade existente: Modelagem Agregada de Carga; Equivalentes de Redes; Estimação de Estados das Distorções Harmônicas. Através das contribuições feitas nesses tópicos, torna-se possível a consideração de aspectos que antes eram ignorados na avaliação harmônica das redes de transporte de energia elétrica e, assim, permite-se uma verificação precisa dos impactos da característica distribuída da geração de harmônicos nos sistemas elétricos de potência. / The growing rate of harmonic generation present in the electric power systems has gained special attention in the planning process of power networks. The major factor that contributed for this new context is the increasing harmonic generation observed in regions that did not use to represent any concern in the past. One of the main causes for this new trend is the distributed characteristic of the harmonic generation. In this new environment, sophisticated methods and models have become necessary, in order to precisely represent the electric elements behaviour and to accurately evaluate the systems performance. As a result, the research work presented in this thesis focused in three different topics, in order to provide contributions that would lead to a more accurate performance evaluation of the power networks and that would provide results closer to the values found in the field: Aggregate Load Modeling; Network Equivalents; Harmonic State Estimation. These contributions would allow the consideration of aspects that normally are ignored in the harmonic assessment of power systems. Consequently, the evaluation of the impacts caused by the distributed generation of harmonics becomes more accurate.

principais teorias acerca do som musical na Antiguidade grega, entre o final do século VI a.C. e o início do século III a.C. O estudo analisa, em primeiro lugar, as circunstâncias históricas e materiais que propiciaram o desenvolvimento da teoria musical grega, chamada harmônica, e a sua relação com a prática musical do período em questão. A primeira teoria analisada está inserida no contexto da escola pitagórica, em que a cosmologia é o referencial de uma visão de mundo que se expande conectando todas as áreas do pensamento, e um dos pontos de origem é a harmônica matemática. São apresentadas a seguir as demonstrações feitas a partir do cálculo das médias proporcionais e sua relação com o princípio da coesão harmônica da oitava. No segundo capítulo são estudadas as teorias acústicas da Antiguidade, que se originaram das razões pitagóricas e se desenvolveram no âmbito das ciências naturais, aprofundando-se com a filosofia aristotélica. No terceiro capítulo, são analisados os principais pontos de confronto promovidos pela corrente aristoxeniana, que se insere no quadro epistemológico aristotélico, e que foram levantados contra os pitagóricos. Nessa nova forma de pensamento, a harmônica é estudada como uma tékne, que tem uma linguagem especializada particular e um objeto específico, o mélos. Ganha importância especial o conceito de aisthésis e, para colocá-lo em prática, a idéia de dynamis torna-se central. Por fim, é apresentada a persistência da concepção pitagórica nos cálculos dos intervalos musicais a partir da divisão do cânone. / This work presents the central ideas related to two main theories about musical sound in greek Antiquity between the end of VI century and the beginning of III B.C. First, the historical and material contexts that lead to the development of greek musical theory, called Harmonics, are investigated, and its relationship with the musical practice of the period. The first theory analyzed comes from the pythagorean school, in which cosmology is the framework of a world view that expands connecting all areas of thought and one of its departure point is mathematical Harmonics. Afterwards, I discuss the demonstrations that are done from the calculations of proportional medias and their relations with the octave harmonic cohesion principle. In the second chapter, its exposed the acoustic theories of Antiquity which originated from the musical ratios and had developed in the branch of natural sciences, deepening by the Aristotelian Philosophy. In the third chapter, I presented the most important issues concerning the differences between the aristoxenian current, which belongs to the aristotelian epistemological framework, against the pythagoreans. In this new way of thought, Harmonics is studied as a tékne that has a particular range of specialized terms and a specific object, the mélos. The concept of aisthésis assumes relevance and to put it into practice, the idea of dynamis becomes central. At last, the persistency of the pythagorean conception it is presented in the calculations of the musical intervals in the division of the canon.

Firstly, this thesis investigates the electrical power harmonics in an attempt to utilize harmonic current and its distortion power in a novel idea to reconvert the distortion power into useful power. This is done, in order to feed different DC or AC loads in single and three-phase power system by using passive or active filters and accordingly, develop a new topology of hybrid active power filter (HAPF). In addition, this circuit can be considered as a power factor corrector (PFC) because it reduces the total harmonic distortion (THD) and improves the power factor (PF). Secondly, this thesis works on a new design of active power factor correction (APFC) circuit presenting two circuits with the same design principle: the first design consists of two active switches without an external complex control circuit, while the second design contains a single active switch with an additional control circuit. The main contribution of this circuit is 98% reduction of the inductor's value used in the newly proposed PFC circuit in comparison with the conventional boost converter which may lead to a huge reduction in size, weight and the cost of the new PFC circuit. Also, the active switches depend on a carefully designed switching pattern that results in an elimination of the third order harmonic from the input source current which decreases the value of total current harmonic distortion (THDI) to (14%) and improves the input PF to (0.99). Consequently, the simplicity of the design without requiring a complex control circuit and without a snubber circuit plus the minimum size of inductor, gives the newly proposed circuit the superiority on other PFC circuits. Thirdly, this research aims to describe the distortion power through submitting two novel power terms called effective active power (Pef ) & reactive power (Qef ) terms with a new power diagram called Right-Angled Power Triangle (RAPT) Diagram. In addition, a novel de nition of total apparent power (St) has been submitted in order to illustrate the physical meaning of (St) in non-sinusoidal systems. The new RAPT Diagram is based on the orthogonality law and depends on geometrical summation to describe the relationship between different aspects (apparent-active-reactive) of power, and different components (total-fundamental distortion), drawing a bridge to connect the time domain with the frequency domain in a two-dimensional diagram.

Made available in DSpace on 2016-04-28T20:38:54Z (GMT). No. of bitstreams: 1 Xochiquetzaly Yeruti de Avila Ramirez.pdf: 1011193 bytes, checksum: 92f8f3079de72ecef87bdf8f907f9437 (MD5) Previous issue date: 2014-08-01 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work derives from the clinical observation of patients under treatment in a hospital institution, going through a critical moment. Bringing together clinical report and metapsychology-making of the case, a panel is presented following the postulates of the Clincal Method and Fundamental Psychopathology. It delves into the psychic dimensions implied in cases of: acute appendicitis, multiple sclerosis, ghost limb syndrome, and amnesia and blindness due to cranioencephalic post-multitraumatism. We speculate that critical moments are enigmatic forms of reorganization of the body seeking a harmonic. Organic disorders due to illness or accident are possible conditions to reach new balances. We conjecture that reordering in the body is an answer to the paradigm of creative philo-ontogenetic solutions. Introducing into the transference the experience of feeling alive constitutes the element of therapeia, aiming the reestablishment of the vital rhythm of the body, its pulsional harmonics / O presente trabalho deriva da observação clínica com pacientes passando por um momento crítico sob tratamento em instituição hospitalar. Constelando relato clínico e metapsicologização do caso, apresenta-se um painel configurado, seguindo os postulados do Método Clínico e da Psicopatologia Fundamental. Aprofunda-se nas dimensões psíquicas implicadas em casos de: apendicite aguda, esclerose múltipla, dor do membro fantasma, e amnésia e cegueira pós-multitraumatismo cranioencefálico. Especula-se que momentos críticos são formas enigmáticas de reorganização do corpo visando uma harmônica. Distúrbios orgânicos produzidos por doença ou acidente são possíveis condições para atingir novos equilíbrios. Conjetura-se que reordenamentos no corpo respondem ao paradigma de soluções criativas filo-ontogenéticas. Introduzir na transferência a experiência de sentir-se vivo constitui o elemento da terapéia, almejando restabelecer o ritmo vital do corpo, sua harmônica pulsional

O aumento do consumo no Brasil aparte com problemas de abastecimento de energia elétrica na década de 90, durante um período de más condições hidrológicas causou uma preocupação e instou uma pesquisa sobre as formas de redução do consumo. A qualidade de energia não era uma prioridade, cargas não eram tão sensíveis, nem os processos existentes exigiam tanto na qualidade do fornecimento de energia elétrica. A preocupação sobre a qualidade do abastecimento de energia aumentou, principalmente no setor industrial, com o aumento da concorrência nos mercados nacionais e no exterior. A qualidade e a quantidade da produção tornaram-se um item para distinguir o lucro. Desta forma, a qualidade do fornecimento de energia e a continuidade das linhas de produção tornaram-se mais importante. Este trabalho pretende mostrar resultados de um estudo experimental sobre lâmpadas fluorescentes compactas com reator integrado, e algumas conseqüências da sua utilização generalizada. / The increase of the consumption in Brazil aside with problems of supply of electrical energy in the decade of 90, during a period of bad hydrological conditions caused a concern and urged a search for ways of reduction of the consumption. The quality of power was not a priority, loads were not so sensitive nor the existing processes demanded as much as quality of the supply of electric energy. The concern on quality of energy supply increased, mainly in the industrial sector, with the increase of the competition in the domestic markets and overseas. The quality and the amount of production became a distinguished item for the profit. In this way, the quality of energy supply and the continuity of the production lines became more important. This work aims to show results of an experimental survey about compact fluorescent light bulbs with integrated reactor, and some consequences of its generalized use.

A tendência crescente na geração de harmônicos nos sistemas elétricos de potência tem ganhado atenção especial no planejamento das redes de transporte de energia elétrica, uma vez que os crescimentos observados acontecem em regiões que antes não representavam qualquer tipo de preocupação. Um dos principais fatores que contribuíram para esse novo contexto é a característica distribuída da geração de harmônicos. Devido a essa nova realidade, métodos mais aprimorados para avaliação de desempenho e modelos mais precisos para a representação de equipamentos tornaram-se necessários. Sendo assim, a pesquisa realizada para a elaboração da presente tese fundamentou a sua investigação em três tópicos com o intuído de fornecer contribuições que permitissem uma avaliação mais precisa das redes elétricas, proporcionando, assim, resultados mais aderentes com a realidade existente: Modelagem Agregada de Carga; Equivalentes de Redes; Estimação de Estados das Distorções Harmônicas. Através das contribuições feitas nesses tópicos, torna-se possível a consideração de aspectos que antes eram ignorados na avaliação harmônica das redes de transporte de energia elétrica e, assim, permite-se uma verificação precisa dos impactos da característica distribuída da geração de harmônicos nos sistemas elétricos de potência. / The growing rate of harmonic generation present in the electric power systems has gained special attention in the planning process of power networks. The major factor that contributed for this new context is the increasing harmonic generation observed in regions that did not use to represent any concern in the past. One of the main causes for this new trend is the distributed characteristic of the harmonic generation. In this new environment, sophisticated methods and models have become necessary, in order to precisely represent the electric elements behaviour and to accurately evaluate the systems performance. As a result, the research work presented in this thesis focused in three different topics, in order to provide contributions that would lead to a more accurate performance evaluation of the power networks and that would provide results closer to the values found in the field: Aggregate Load Modeling; Network Equivalents; Harmonic State Estimation. These contributions would allow the consideration of aspects that normally are ignored in the harmonic assessment of power systems. Consequently, the evaluation of the impacts caused by the distributed generation of harmonics becomes more accurate.

No presente trabalho se estuda a correlação de diferentes parâmetros de sinais de Ruído Magnético de Barkhausen (RMB) e de fluxo magnético com o comportamento elastoplástico em chapas de aço carbono, visando à aplicação dos resultados como técnica de Ensaio Não-Destrutivo. Comprovou-se que o comportamento de parâmetros como a energia (RMBenegia), o valor quadrático médio(RMBrms) e a envolvente dos sinais de RMB com os diferentes estados elastoplásticos do material resultou fortemente dependente da anisotropia de laminação, quantidade de Carbono e fases, gerados no processo de produção das chapas. Como novidade introduziu-se o parâmetro chamado de Área em baixo da curva da distribuição de pulsos do sinal de Barkhausen. A evolução deste parâmetro com a deformação identificou com boa aproximação a região de transição elasto-plástica do material. Harmônicos não lineares (HNL) do fluxo magnético apresentaram uma melhor correlação com a anisotropia do que com os estados elasto-plásticos do material, mas com alta dependência ao acoplamento sonda-amostra. Enquanto que o RMB apresentou elevados níveis de reprodutibilidade. Propriedades mecânicas e comportamentos característicos de ensaios de tração em regime discreto e contínuo foram reproduzidos e identificados com um alto grau de aproximação pelo RMB e os HNL. Outros métodos magnéticos e não magnéticos usados neste trabalho não apresentaram níveis altos de sensibilidade às mudanças microestruturais devido às deformações elasto-plásticas no material, no entanto o RMB e os HNL identificaram tais mudanças microestruturais dando margem a novas soluções nos campos de ensaio e inspeção não-destrutivos. / The present work studies the relationship between different parameters of the Magnetic Barkhausen Noise (MBN) and non-linear harmonics of the magnetic flux signals (NLH) with the elastic-plastic behavior in carbon steel plates, in an effort to use the results as a non-destructive testing technique. MBN parameters such as the envelope of the MBN signal, and the scalar parameters MBNenergy, MBNrms were found to be highly dependent on the lamination processes, carbon content and phases originated during the fabrication of the samples. A new parameter entitled area under the MBN jump distribution was defined. The behavior of this parameter as strain evolved provided a good approximation of the elastic-plastic transition region. Non-linear harmonics offered a good correlation with both anisotropy and the elasticplastic states of the material, nevertheless depending heavily on the sensor coupling with the sample surface, while at the same time MBN provided good reproducibility. The characteristic behavior as well as the mechanical properties obtained from discrete and continuous tensile strength tests were reproduced by both MBN and HNL. Other magnetic and non-magnetic methods did not show the same level of sensibility to microstructure changes due to elastic-plastic strains when compared to the results obtained using MBN and HNL, giving room to new solutions in the nondestructive inspection and testing fields.