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Formulations and Exact Solution Methods For a Class of New Continous Covering ProblemsCakir, Ozan January 2009 (has links)
<p>This thesis is devoted to introducing new problem formulations and exact solution methods for a class of continuous covering location models. The manuscript includes three self-contained studies which are organized as in the following. </p>
<p> In the first study, we introduce the planar expropriation problem with non-rigid rectangular facilities which has many applications in regional planning and undesirable facility location domains. This model is proposed for determining the locations and formations of two-dimensional rectangular facilities. Based on the geometric properties of such facilities, we developed a new formulation which does not require employing distance measures. The resulting model is a mixed integer nonlinear program. For solving this new model, we derived a continuous branch-and-bound framework utilizing linear approximations for the tradeoff curve associated with the facility formation alternatives. Further, we developed new problem generation and bounding strategies suitable for this particular branch-and-bound procedure. We designed a computational study where we compared this algorithm with two well-known mixed integer nonlinear programming solvers. Computational experience showed that the branch-and-bound procedure we developed performs better than BARON and SBB both in terms of processing time and size of the branching tree.</p>
<p> The second study is referred to as the planar maximal covering problem with single convex polygonal shapes and it has ample applications in transmitter location, inspection of geometric shapes and directional antenna location. In this study, we investigated maximal point containment by any convex polygonal shape in the Euclidean plane. Using a fundamental separation property of convex sets, we derived a mixed integer linear formulation for this problem. We were able to identify two types of special cuts based on the geometric properties of the shapes under study, which were later employed for developing a branch-and-cut procedure for solving this particular location model. We also evaluated the resultant bound quality after employing the afore-mentioned cuts. </p>
<p> In the third study, we discuss the dynamic planar expropriation problem with single convex polygonal shapes. We showed how the basic problem formulations discussed in the first two studies extend to their diametric opposites, and further to models in higher dimensions. Subsequently, we allowed a dynamic setting where the shape under study is expected to function over a finite planning horizon and the system parameters such as the fixed point locations and expropriation costs are subject to change. The shape was permitted to relocate at the beginning of each time period according to particular relocation costs. We showed that this dynamic problem structure can be decomposed into a set of static problems under a particular vector of relocations. We discussed the solution of this model by two enumeration procedures. Subsequently, we derived an incomplete dynamic programming procedure which is suitable for this distinct problem structure. In this method, there is no need to evaluate all the branches of the branching tree and one proceeds with keeping the minimum stage cost. The evaluation of a branch is postponed until relocation takes place in the lower-level problems. With this postponing structure, the procedure turned out to be superior to the two enumeration procedures in terms of tree size. </p> / Thesis / Doctor of Philosophy (PhD)
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Breaking The Boxdaylight shaping architectureMohamed, Khalid January 2019 (has links)
It is well-known that daylight is a fundamental element to experiencean architectural space. In spite of that, there are limitedresources that consider how to form that space based ondaylight. This paper constitutes ‘Breaking the Box’ as a newconcept, which can be taken by architects, lighting designersand urban planners in parallel to their daylight design techniquesas a tool in design practice.‘Breaking the Box’ has its origin in the destruction of the boxconcept, a design method of the modern architecture pioneerFrank Lloyd Wright. Thus, it is an attempt to develop Wright’stheory in relation to daylight. The paper investigates severalqualitative and quantitative sub-tools in case studies andexperimental models, exploring a variety of configurations inspatial relationships and form to assess different characteristicsof daylight in residential environments.The aim of the study is to understand and control the penetrationof daylight qualities – considering both diffused skylightand direct sunlight – within a space in different latitudes.Thus, preserving the view and making the quality of daylightthe founding element shaping architecture by breaking thebox. The study revealed a strong relationship between daylightqualities and architectural form. As a result, it is evidencethat daylight does shape architecture. When it comes to incorporatingdaylight, form does not follow function but formand function are one.
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Shape Memory Behavior of Ionomers and Their CompoundsDolog, Rostyslav January 2013 (has links)
No description available.
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[pt] CLUSTERIZAÇÃO BASEADA EM GRAFO EM ESPAÇO DE CARACTERÍSTICAS PROFUNDO PARA CORRESPONDÊNCIA DE FORMAS / [en] GRAPH-BASED CLUSTERING IN DEEP FEATURE SPACE FOR SHAPE MATCHINGDANIEL LUCA ALVES DA SILVA 02 July 2024 (has links)
[pt] Projetos de engenharia dependem de modelos CAD 3D complexos durante todo o seu ciclo de vida. Esses modelos 3D contêm milhões de geometrias que impõem desafios de armazenamento, transmissão e renderização.
Trabalhos anteriores empregaram com sucesso técnicas de correspondência de
formas baseadas em aprendizado profundo para reduzir a memória exigida por
esses modelos 3D. Este trabalho propõe um algoritmo baseado em grafos que
melhora o agrupamento não supervisionado em espaços profundos de características. Essa abordagem refina drasticamente a precisão da correspondência
de formas e resulta em requisitos de memória ainda mais baixos para os modelos 3D. Em um conjunto de dados rotulado, nosso método atinge uma redução
de 95 por cento do modelo, superando as técnicas não supervisionadas anteriores que
alcançaram 87 por cento e quase atingindo a redução de 97 por cento de uma abordagem totalmente supervisionada. Em um conjunto de dados não rotulado, nosso método
atinge uma redução média do modelo de 87 por cento contra uma redução média de
77 por cento das técnicas não supervisionadas anteriores. / [en] Engineering projects rely on complex 3D CAD models throughout their
life cycle. These 3D models comprise millions of geometries that impose storage, transmission, and rendering challenges. Previous works have successfully
employed shape-matching techniques based on deep learning to reduce the
memory required by these 3D models. This work proposes a graph-based algorithm that improves unsupervised clustering in deep feature space. This approach dramatically refines shape-matching accuracy and results in even lower
memory requirements for the 3D models. In a labeled dataset, our method
achieves a 95 percent model reduction, outperforming previous unsupervised techniques that achieved 87 percent and almost reaching the 97 percent reduction from a fully
supervised approach. In an unlabeled dataset, our method achieves an average model reduction of 87 percent versus an average reduction of 77 percent from previous
unsupervised techniques.
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Estudo das relaxações estruturais alfa e beta em poli(metacrilatos de n-alquila) utilizando-se RMN / Study of the structural relaxation alpha and beta in poly(n-methyl-acrylates) using RMNTozoni, José Roberto 15 April 2005 (has links)
O comportamento das formas de linha dos espectros de RMN estático em função da temperatura assim como os experimentos de PURE Exchange em uma dimensão (PUREX-1D) foram utilizados para elucidar detalhes da dinâmica molecular nos PnMA. Os experimentos PUREX-1D foram realizados na faixa de temperatura de Tg-145 o C a Tg. Nesta faixa de temperatura a dinâmica molecular dos PnMA acontece com tempos de correlação entre 500 micro e 10 milissegundos. Utilizando simulação espectral foi demonstrado que os espectros PUREX-1D dependem tanto do tempo de correlação quanto da geometria das reorientações moleculares. Este fato também foi usado para avaliar as características dos movimentos moleculares responsáveis pela reaxação estrutural beta nos PnMA. Foi observado que os pequenos ângulos de reorientação da cadeia principal associados com a relaxação estrutural beta aumentam com o aumento da temperatura e que os tempos de correlação do movimento podem apresentar uma larga distribuição. Análises das formas de linha obtidas através de experimentos de polarização cruzada (CP) em função da temperatura foram realizadas para se estudar o comportamento da dinâmica molecular responsável pela relaxações estruturais alfa e beta nos PnMA. Os experimentos CP foram realizados em uma faixa de temperaturas entre Tg-50 o C e Tg.+70 o C. Nesta faixa de temperatura as figuras de linha de RMN estática são altamente dependentes da temperatura, do tamanho e do volume do ramo lateral. A dinâmica molecular dos PnMA apresentou um movimento altamente anisotrópico sendo que a isotropização da conformação do espectro induzida pelos movimentos moleculares ocorreu apenas a temperaturas muito acima da Tg, contrariando o comportamento esperado para a maioria dos polímeros amorfos. / The behavior of the static NMR line shapes as a function of the temperature as well as one-dimensional Pure Exchange NMR experiments (PUREX-1D) were used to elucidate details of the molecular dynamics in PnMAs. The 1D-PUREX experiments were carried out in the temperature range of Tg-145 oC to Tg. In this range of temperature the molecular dynamics of PnMAs was found to occur with correlation times between 500m and 10ms. Using spectral simulations it was demonstrated that the 1D-PUREX spectra depend on both, the correlation time and geometry of the molecular reorientations. Hence this feature was used to evaluate the characteristics of the molecular motions responsible by the b structural relaxation of PnMAs. It was found that the small angles reorientation of main chain associated with the b-structural relaxation increases with the temperature and the correlation times present a possible broad distribution. Analysis of the NMR line shapes obtained in Cross Polarization (CP) experiments as a function of temperature was performed to study the behavior of the molecular dynamics responsible for the b and a structural relaxation. The CP experiments were performed in the temperature range of Tg-50 oC to Tg+70 oC. In this temperature range the static NMR line shapes are highly dependent on the temperature, size and bulk of the side-group. The dynamics of the PnMA presents a highly anisotropic motion and the isotropisation of conformation induced by the motion only occurs in temperatures well above Tg, contrary to the behavior of the most fragile amorphous polymers.
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Combinatoire bijective des permutations et nombres de Genocchi / Bijective combinatorics of permutations and Genocchi numbersBigeni, Ange 24 November 2015 (has links)
Cette thèse a pour contexte la combinatoire énumérative et décrit la construction de plusieurs bijections entre modèles combinatoires connus ou nouveaux de suites d'entiers et polynômes, plus particulièrement celle des nombres de Genocchi (et de leurs extensions, les polynômes de Gandhi) qui interviennent dans diverses branches des mathématiques et dont les propriétés combinatoires sont de ce fait activement étudiées, et celles de polynômes q-eulériens associés aux quatre statistiques fondamentales de MacMahon sur les permutations ainsi qu'à des statistiques analogues. On commence par définir les permutations de Dumont normalisées, un modèle combinatoire des nombres de Genocchi médians normalisés q-étendus, notés ¯cn(q) et définis par Han et Zeng, puis l'on construit une première bijection entre ce modèle et l'ensemble des configurations de Dellac, autre interprétation combinatoire de ¯cn(q) mise en évidence par Feigin dans le contexte de la géométrie des grassmanniennes de carquois. En s'appuyant sur la théorie des fractions continues de Flajolet, on en construit finalement un troisième modèle combinatoire à travers les histoires de Dellac, que l'on relie aux premiers modèles sus-cités au moyen d'une seconde bijection. On s'intéresse ensuite à la classe combinatoire des k-formes irréductibles définies par Hivert et Mallet dans l'étude des k-fonctions de Schur, et qui faisaient l'objet d'une conjecture supposant que les polynômes de Gandhi sont générés par les k-formes irréductibles selon la statistique des k-sites libres. On construit une bijection entre les k-formes irréductibles et les pistolets surjectifs de hauteur k − 1 (connus pour générer les polynômes de Gandhi selon la statistique des points fixes) envoyant les k-sites libres des premières sur les points fixes des seconds, démontrant de ce fait la conjecture. Enfin, on établit une nouvelle identité combinatoire entre deux polynômes q-eulériens définis par des statistiques eulériennes et mahoniennes sur l'ensemble des permutations d'un ensemble fini, au moyen d'une dernière bijection sur les permutations, qui envoie une suite finie de statistiques sur une autre / This work is set in the context of enumerative combinatorics and constructs several statistic-preserving bijections between known or new combinatorial models of sequences of integers or polynomials, espacially the sequence of Genocchi numbers (and their extensions, the Gandhi polynomials) which appear in numerous mathematical theories and whose combinatorial properties are consequently intensively studied, and two sequences of q-Eulerian polynomials associated with the four fundamental statistics on permutations studied by MacMahon, and with analog statistics. First of all, we define normalized Dumont permutations, a combinatorial model of the q-extended normalized median Genocchi numbers ¯cn(q) introduced by Han and Zeng, and we build a bijection between the latter model and the set of Dellac configurations, which have been proved by Feigin to generate ¯cn(q) by using the geometry of quiver Grassmannians. Then, in order to answer a question raised by the theory of continued fractions of Flajolet, we define a new combinatorial model of ¯cn(q), the set of Dellac histories, and we relate them with the previous combinatorial models through a second statistic-preserving bijection. Afterwards, we study the set of irreducible k-shapes defined by Hivert and Mallet in the topic of k-Schur functions, which have been conjectured to generate the Gandhi polynomials with respect to the statistic of free ksites. We construct a statistic-preserving bijection between the irreducible k-shapes and the surjective pistols of height k−1 (well-known combinatorial interpretation of the Gandhi polynomials with respect to the fixed points statistic) mapping the free k-sites to the fixed points, thence proving the conjecture. Finally, we prove a new combinatorial identity between two eulerian polynomials defined on the set of permutations thanks to Eulerian and Mahonian statistics, by constructing a bijection on the permutations, which maps a finite sequence of statistics on another
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Représentation et enregistrement de formes visuelles 3D à l'aide de Laplacien graphe et noyau de la chaleur / Representation & Registration of 3D Visual Shapes using Graph Laplacian and Heat KernelSharma, Avinash 29 October 2012 (has links)
Analyse de la forme 3D est un sujet de recherche extrêmement actif dans les deux l'infographie et vision par ordinateur. Dans la vision par ordinateur, l'acquisition de formes et de modélisation 3D sont généralement le résultat du traitement des données complexes et des méthodes d'analyse de données. Il existe de nombreuses situations concrètes où une forme visuelle est modélisé par un nuage de points observés avec une variété de capteurs 2D et 3D. Contrairement aux données graphiques, les données sensorielles ne sont pas, dans le cas général, uniformément répartie sur toute la surface des objets observés et ils sont souvent corrompus par le bruit du capteur, les valeurs aberrantes, les propriétés de surface (diffusion, spécularités, couleur, etc), l'auto occlusions, les conditions d'éclairage variables. Par ailleurs, le même objet que l'on observe par différents capteurs, à partir de points de vue légèrement différents, ou à des moments différents cas peuvent donner la répartition des points tout à fait différentes, des niveaux de bruit et, plus particulièrement, les différences topologiques, par exemple, la fusion des mains. Dans cette thèse, nous présentons une représentation de multi-échelle des formes articulés et concevoir de nouvelles méthodes d'analyse de forme, en gardant à l'esprit les défis posés par les données de forme visuelle. En particulier, nous analysons en détail le cadre de diffusion de chaleur pour représentation multi-échelle de formes 3D et proposer des solutions pour la segmentation et d'enregistrement en utilisant les méthodes spectrales graphique et divers algorithmes d'apprentissage automatique, à savoir, le modèle de mélange gaussien (GMM) et le Espérance-Maximisation (EM). Nous présentons d'abord l'arrière-plan mathématique sur la géométrie différentielle et l'isomorphisme graphique suivie par l'introduction de la représentation spectrale de formes 3D articulés. Ensuite, nous présentons une nouvelle méthode non supervisée pour la segmentation de la forme 3D par l'analyse des vecteurs propres Laplacien de graphe. Nous décrivons ensuite une solution semi-supervisé pour la segmentation de forme basée sur un nouveau paradigme d'apprendre, d'aligner et de transférer. Ensuite, nous étendre la représentation de forme 3D à une configuration multi-échelle en décrivant le noyau de la chaleur cadre. Enfin, nous présentons une méthode d'appariement dense grâce à la représentation multi-échelle de la chaleur du noyau qui peut gérer les changements topologiques dans des formes visuelles et de conclure par une discussion détaillée et l'orientation future des travaux. / 3D shape analysis is an extremely active research topic in both computer graphics and computer vision. In computer vision, 3D shape acquisition and modeling are generally the result of complex data processing and data analysis methods. There are many practical situations where a visual shape is modeled by a point cloud observed with a variety of 2D and 3D sensors. Unlike the graphical data, the sensory data are not, in the general case, uniformly distributed across the surfaces of the observed objects and they are often corrupted by sensor noise, outliers, surface properties (scattering, specularities, color, etc.), self occlusions, varying lighting conditions. Moreover, the same object that is observed by different sensors, from slightly different viewpoints, or at different time instances may yield completely different point distributions, noise levels and, most notably, topological differences, e.g., merging of hands. In this thesis we outline single and multi-scale representation of articulated 3D shapes and devise new shape analysis methods, keeping in mind the challenges posed by visual shape data. In particular, we discuss in detail the heat diffusion framework for multi-scale shape representation and propose solutions for shape segmentation and dense shape registration using the spectral graph methods and various other machine learning algorithms, namely, the Gaussian Mixture Model (GMM) and the Expectation Maximization (EM). We first introduce the mathematical background on differential geometry and graph isomorphism followed by the introduction of pose-invariant spectral embedding representation of 3D articulated shapes. Next we present a novel unsupervised method for visual shape segmentation by analyzing the Laplacian eigenvectors. We then outline a semi-supervised solution for shape segmentation based upon a new learn, align and transfer paradigm. Next we extend the shape representation to a multi-scale setup by outlining the heat-kernel framework. Finally, we present a topologically-robust dense shape matching method using the multi-scale heat kernel representation and conclude with a detailed discussion and future direction of work.
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Estudo das relaxações estruturais alfa e beta em poli(metacrilatos de n-alquila) utilizando-se RMN / Study of the structural relaxation alpha and beta in poly(n-methyl-acrylates) using RMNJosé Roberto Tozoni 15 April 2005 (has links)
O comportamento das formas de linha dos espectros de RMN estático em função da temperatura assim como os experimentos de PURE Exchange em uma dimensão (PUREX-1D) foram utilizados para elucidar detalhes da dinâmica molecular nos PnMA. Os experimentos PUREX-1D foram realizados na faixa de temperatura de Tg-145 o C a Tg. Nesta faixa de temperatura a dinâmica molecular dos PnMA acontece com tempos de correlação entre 500 micro e 10 milissegundos. Utilizando simulação espectral foi demonstrado que os espectros PUREX-1D dependem tanto do tempo de correlação quanto da geometria das reorientações moleculares. Este fato também foi usado para avaliar as características dos movimentos moleculares responsáveis pela reaxação estrutural beta nos PnMA. Foi observado que os pequenos ângulos de reorientação da cadeia principal associados com a relaxação estrutural beta aumentam com o aumento da temperatura e que os tempos de correlação do movimento podem apresentar uma larga distribuição. Análises das formas de linha obtidas através de experimentos de polarização cruzada (CP) em função da temperatura foram realizadas para se estudar o comportamento da dinâmica molecular responsável pela relaxações estruturais alfa e beta nos PnMA. Os experimentos CP foram realizados em uma faixa de temperaturas entre Tg-50 o C e Tg.+70 o C. Nesta faixa de temperatura as figuras de linha de RMN estática são altamente dependentes da temperatura, do tamanho e do volume do ramo lateral. A dinâmica molecular dos PnMA apresentou um movimento altamente anisotrópico sendo que a isotropização da conformação do espectro induzida pelos movimentos moleculares ocorreu apenas a temperaturas muito acima da Tg, contrariando o comportamento esperado para a maioria dos polímeros amorfos. / The behavior of the static NMR line shapes as a function of the temperature as well as one-dimensional Pure Exchange NMR experiments (PUREX-1D) were used to elucidate details of the molecular dynamics in PnMAs. The 1D-PUREX experiments were carried out in the temperature range of Tg-145 oC to Tg. In this range of temperature the molecular dynamics of PnMAs was found to occur with correlation times between 500m and 10ms. Using spectral simulations it was demonstrated that the 1D-PUREX spectra depend on both, the correlation time and geometry of the molecular reorientations. Hence this feature was used to evaluate the characteristics of the molecular motions responsible by the b structural relaxation of PnMAs. It was found that the small angles reorientation of main chain associated with the b-structural relaxation increases with the temperature and the correlation times present a possible broad distribution. Analysis of the NMR line shapes obtained in Cross Polarization (CP) experiments as a function of temperature was performed to study the behavior of the molecular dynamics responsible for the b and a structural relaxation. The CP experiments were performed in the temperature range of Tg-50 oC to Tg+70 oC. In this temperature range the static NMR line shapes are highly dependent on the temperature, size and bulk of the side-group. The dynamics of the PnMA presents a highly anisotropic motion and the isotropisation of conformation induced by the motion only occurs in temperatures well above Tg, contrary to the behavior of the most fragile amorphous polymers.
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Formas geometricas e qualidade acustica de salas de aula : estudo de caso em Campinas-SP / Geometric shapes and classroom acoustical quality : case study at Campinas-SPAmorim, Adriana Eloa Bento 22 August 2007 (has links)
Orientador: Stelamaris Rolla Bertoli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-09T02:39:04Z (GMT). No. of bitstreams: 1
Amorim_AdrianaEloaBento_M.pdf: 15352732 bytes, checksum: 327b5fe0a18f76c48649f2007c4f4dba (MD5)
Previous issue date: 2007 / Resumo: Estudos sobre a acústica de salas de aula estão cada vez mais comuns no meio acadêmico e científico, devido à sua influência nas questões do ensino-aprendizagem. Os ambientes escolares exigem qualidade acústica que deve ser prevista já na concepção do projeto. A inadequação acústica de escolas e salas de aula é apontada em diversas pesquisas que utilizam variadas metodologias, geralmente através da aplicação de testes de acertos e erros de vocábulos, e também da análise de parâmetros de avaliação como medidas dos níveis de pressão sonora e do tempo de reverberação. Na rede estadual de ensino público em São Paulo, as salas de aula são projetadas a partir de diretrizes pré-estabelecidas que visam a padronização dos projetos de escolas. Portanto, este trabalho tem como objetivos identificar as formas geométricas mais comuns de salas de aula propostas para a rede pública estadual de ensino em Campinas-SP, apresentar o comportamento dos parâmetros acústicos quanto à inteligibilidade da fala e apontar as formas mais favoráveis à qualidade acústica de salas de aula. Para a definição da amostra realizou-se um levantamento cadastral das escolas e o levantamento arquitetônico das salas. Desse levantamento, identificou-se o número de configurações geométricas mais comuns de salas. Foram analisadas as salas dentro da uma mesma configuração padrão, totalizando dezessete salas de aula. Para a medição acústica foi utilizada a técnica da resposta impulsiva da sala e os parâmetros acústicos foram obtidos através do programa de avaliação acústica de salas, o DIRAC®, da empresa Brüel & Kjaer. Os parâmetros derivados da resposta impulsiva analisados neste trabalho foram: o Tempo de Reverberação (TR), o Tempo de Decaimento Inicial (EDT), a Definição (D50), o Índice de Transmissão da Fala (STI) e a Porcentagem de Perda na Articulação de Consoantes (%ALCons), em função da freqüência na faixa de bandas de 1/1 de oitava. Também foi medido e analisado o Nível de Pressão Sonora ou ruído de fundo ambiental equivalente (LAeq) interno e externo à sala, obtido com o medidor de pressão sonora. A análise complementar da forma para cada sala foi feita pela proporcionalidade das dimensões, segundo a escala do Diagrama de Bolt. As formas geométricas em planta mais comuns de salas são as quadradas (7x7m) e retangulares (6x8m). Dentro de cada configuração as salas apresentaram diferentes desempenhos acústicos. Pelo fato de existir uma grande variedade de fatores e parâmetros que interferem na acústica da sala, foi possível identificar algumas tendências de comportamento acústico por configuração geométrica / Abstract: Studies about classroom acoustics are developed each time more into the scientific and academic society, due to its influence in the teach-learning. The school¿s environments demand acoustical quality that must be foreseen already during the design planning. Some situations of acoustic not adjusted on classrooms are shown in research that using several methods, generally with application of word¿s rightness and error tests as well as of the analysis and evaluation of parameters as the sound pressure levels and reverberation time. In the State of Sao Paulo the classrooms of public education buildings are projected in accordance with same lines of direction that aim at the school design standardization. Therefore, this work has as objective to identify what geometric shapes are more common on classroom¿s design found in public schools at Campinas-SP, to present the acoustic parameters behavior how much to the speech intelligibility of classrooms and to point the shapes that are most favorable to the acoustical quality for classrooms. It was made classroom¿s cadastral survey for sample definition and after was made architectural survey hers. This procedure allows identifying the number of the rooms more common geometric configurations. The classrooms which have the same configuration standard were selected and analyzed, totalizing seventeen classrooms. The acoustical measurements were made using the impulse response technique of the room and the acoustical parameters were obtained of the room acoustics evaluation software, the DIRAC®, by Brüel & Kjaer. The parameters were derived from the impulse response were analyzed in this work: Reverberation Time (RT), Early Decay Time (EDT), Definition (D50), Speech Transmission Index (STI) and Percentage Articulation Loss of Consonants (%ALCons), for each 1/1 octave frequency band. Also it was analyzed the internal and external background noise or ambiental Equivalent Sound Pressure Level (LAeq), which were measured with sound pressure level meter. Complementary analysis of the form for each room was made by the proportionality of the dimensions, according to Bolt¿s Diagram scale. Among the more common geometric shapes in plant of rooms had found were: the square shaped (7x7m) and rectangular (6x8m). Inside each configuration of classroom had presented different acoustical performances. For the fact to exist a great variety of factors and parameters intervening on classroom acoustics, it was possible to identify some acoustical behaviors trends for geometric configuration / Mestrado / Arquitetura e Construção / Mestre em Engenharia Civil
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Efficient Feature Extraction for Shape Analysis, Object Detection and TrackingSolis Montero, Andres January 2016 (has links)
During the course of this thesis, two scenarios are considered. In the first one, we contribute to feature extraction algorithms. In the second one, we use features to improve object detection solutions and localization. The two scenarios give rise to into four thesis sub-goals. First, we present a new shape skeleton pruning algorithm based on contour approximation and the integer medial axis. The algorithm effectively removes unwanted branches, conserves the connectivity of the skeleton and respects the topological properties of the shape. The algorithm is robust to significant boundary noise and to rigid shape transformations. It is fast and easy to implement. While shape-based solutions via boundary and skeleton analysis are viable solutions to object detection, keypoint features are important for textured object detection. Therefore, we present a keypoint featurebased planar object detection framework for vision-based localization. We demonstrate that our framework is robust against illumination changes, perspective distortion, motion
blur, and occlusions. We increase robustness of the localization scheme in cluttered environments and decrease false detection of targets. We present an off-line target evaluation strategy and a scheme to improve pose. Third, we extend planar object detection to a real-time approach for 3D object detection using a mobile and uncalibrated camera. We develop our algorithm based on two novel naive Bayes classifiers for viewpoint and feature matching that improve performance and decrease memory usage. Our algorithm exploits the specific structure of various binary descriptors in order to boost feature matching by conserving descriptor properties. Our novel naive classifiers require a database with a small memory footprint because we only store efficiently encoded features. We improve the feature-indexing scheme to speed up the matching process creating a highly efficient database for objects. Finally, we present a model-free long-term tracking algorithm based on the Kernelized Correlation Filter. The proposed solution improves the correlation tracker based on precision, success, accuracy and robustness while increasing frame rates. We integrate adjustable Gaussian window and sparse features for robust scale estimation creating a better separation of the target and the background. Furthermore, we include fast descriptors and Fourier spectrum packed format to boost performance while decreasing the memory footprint. We compare our algorithm with state-of-the-art techniques to validate the results.
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