Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-05-31T13:46:49Z No. of bitstreams: 1 renanaugustodembogurski.pdf: 5268461 bytes, checksum: c9599f64f511590d6ff74c1f707b6e08 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-06-01T11:34:15Z (GMT) No. of bitstreams: 1 renanaugustodembogurski.pdf: 5268461 bytes, checksum: c9599f64f511590d6ff74c1f707b6e08 (MD5) / Made available in DSpace on 2017-06-01T11:34:15Z (GMT). No. of bitstreams: 1 renanaugustodembogurski.pdf: 5268461 bytes, checksum: c9599f64f511590d6ff74c1f707b6e08 (MD5) Previous issue date: 2013-03-06 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho apresenta um método que permite a deformação de um terreno pela modificação do seu mapa de alturas em um ambiente de realidade aumentada. A estrutura hierárquica de malhas A4-8 foi utilizada para representar o terreno. Essa estrutura define um espaço paramétrico para calcular as coordenadas de um terreno no espaço Euclidiano R3. Em especial, este trabalho lida com o problema de modelagem de terrenos esféricos. Uma métrica de erro dependente do observador e da geometria do terreno utilizada tanto para sua observação quanto para sua modelagem. Os resultados demonstram que o uso da malha A4-8 em conjunto com o sistema de realidade aumentada tangível é flexível para modelar terrenos esféricos e pode ser facilmente modificada para terrenos com a topologia do cilindro e do toro. O desenvolvimento de um método de geração de malhas eficiente e de uso intuitivo, baseado em marcadores de realidade aumentada, é a principal contribuição deste trabalho. / This work presents a method that allows the deformation of a terrain by modifying your heightmap in an augmented reality environment. The hierarchical structure of A4 8 meshes was used to represent terrains. This structure defines a parameter space to calculate the coordinates of a field in the R3 Euclidean space. In particular, this paper deals with the problem of modeling spherical terrains. An error metric dependent on the observer and the geometry of the land used for its observation and modeling. The results demonstrate that the use of A4-8 mesh combined with the tangible augmented reality system is flexible to shape spherical terrains and can be easily modified to deal with other topologies, such as the torus and the cylinder. The development of an efficient and intuitive to use method for mesh generation, based on augmented reality markers, is the main contribution of this work.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-06-06T13:21:41Z No. of bitstreams: 1 joaovitordesahauck.pdf: 33226275 bytes, checksum: b7a8ed469369e9bbccd22738ced13ab0 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-06-06T14:07:12Z (GMT) No. of bitstreams: 1 joaovitordesahauck.pdf: 33226275 bytes, checksum: b7a8ed469369e9bbccd22738ced13ab0 (MD5) / Made available in DSpace on 2017-06-06T14:07:12Z (GMT). No. of bitstreams: 1 joaovitordesahauck.pdf: 33226275 bytes, checksum: b7a8ed469369e9bbccd22738ced13ab0 (MD5) Previous issue date: 2015 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Malhas com restrições no comprimento das arestas são úteis para diversas aplicações, especialmente para simulações de processos químicos e físicos. Este trabalho apresenta um método iterativo para remalhar uma malha triangular arbitraria de variedade 2 em uma malha com o comprimento de todas as arestas dentro de um intervalo de restrição definido pelo usuário. O método usa operações estelares para ajustar a quantidade de vértices e triângulos no modelo e para melhorar a valência dos vértices. Ele também aplica o operador Laplaciano em um espaço paramétrico local para melhorar a distribuição de vértices sobre a superfície. Propõe-se, uma otimização não linear, aplicada localmente, para os casos em que a malha é praticamente regular. Perdas geométricas são evitadas pela realização de uma projeção sobre a superfície original. O método proposto resulta em uma malha praticamente regular, com os vértices distribuídos uniformemente sobre a superfície. A dual da malha é usada em simulações de nano estruturas de carbono como uma aplicação do método. A principal contribuição deste trabalho é uma nova abordagem para restringir explicitamente o comprimento das arestas em um intervalo dado. Nosso método ainda garante baixa perda global de geometria e baixo custo de memória em comparação com métodos disponíveis na literatura. / Meshes with constraints in the edge length are useful for several applications, spe-cially for chemical and physical simulations. This work presents an iterative method for remeshing an arbitrary triangular 2-manifold mesh into a mesh with all edge lengths within an user-defined constraining interval. The method uses stellar operations to adjust the amount of vertices and triangles in the model and for improving the valence of the vertices. It also applies the Laplacian operator in a local parametric space to improve the distribution of the vertices over the surface. We propose a nonlinear optimization, locally applied, for cases in which the mesh is almost regular. Geometric losses are prevented by performing a projection over the original surface. Our method results in a nearly regu-lar mesh, with vertices uniformly distributed over the surface. The dual of the mesh is used in simulations of carbon nanostructures as an application of the method. The main contribution of this work is a new approach for constraining the edge length within an explicitly given interval. Our method also ensures lower global geometry losses and lower memory cost in comparison to methods available in the literature.

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-04-11T18:45:14Z No. of bitstreams: 1 jefersondiasgoncalves.pdf: 877599 bytes, checksum: 55b47e460c6f0960d499ee03cfdfbd27 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-04-11T19:36:44Z (GMT) No. of bitstreams: 1 jefersondiasgoncalves.pdf: 877599 bytes, checksum: 55b47e460c6f0960d499ee03cfdfbd27 (MD5) / Made available in DSpace on 2018-04-11T19:36:44Z (GMT). No. of bitstreams: 1 jefersondiasgoncalves.pdf: 877599 bytes, checksum: 55b47e460c6f0960d499ee03cfdfbd27 (MD5) Previous issue date: 2018-02-27 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nesta tese expomos primeiramente um breve histórico-motivacional para a construção de uma teoria de gravitação quântica, bem como, rápidas revisões orientadas sobre elementos de teorias quânticas de campos e sobre a técnica de Schwinger-Dewitt. De posse destas ferramentas, discutimos a dependência de calibre e da parametrização para uma teoria quântica de gravitação em um espaço-tempo de dimensão arbitrária D. Com este objetivo, calculamos explicitamente as correções quânticas a 1-loop, da ação efetiva da teoria, considerando a parametrização mais geral possível para a métrica quântica. Essa parametrização contém inicialmente sete parâmetros, sendo que alguns deles serão fixados através da condição de fixação de calibre, o que torna o nosso cálculo um pouco mais simples. Por fim, para esta teoria, confirmamos a validade de um teorema geral, o qual garante a independência das divergências on-shell, a 1-loop, com respeito às ambiguidades nas escolhas de calibre e de parametrização da métrica quântica. / In this thesis we first present a brief historical-motivational for a construction of a theory of quantum gravitation, as well as quick reviews oriented on elements of quantum field theory and Schwinger- Dewitt technique. In possession of these tools, the gauge and parametrization dependence is discussed in quantum gravity in an arbitrary dimension D. Explicit one-loop calculations are performed within the most general parametrization of quantum metric with seven arbitrary parameters. On the other hand, some of the gauge fixing parameters are fixed to make the calculations relatively simple. We confirm the general theorem stating that the on shell local terms in the one-loop effective action are independent of the gauge and parametrization ambiguity.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2018-08-13T13:07:32Z No. of bitstreams: 1 fernandotadeudearaujolima.pdf: 30345992 bytes, checksum: 11b123f41224b7ae8946de219847f74e (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-08-13T13:08:14Z (GMT) No. of bitstreams: 1 fernandotadeudearaujolima.pdf: 30345992 bytes, checksum: 11b123f41224b7ae8946de219847f74e (MD5) / Made available in DSpace on 2018-08-13T13:08:14Z (GMT). No. of bitstreams: 1 fernandotadeudearaujolima.pdf: 30345992 bytes, checksum: 11b123f41224b7ae8946de219847f74e (MD5) Previous issue date: 2017-04-29 / PROQUALI (UFJF) / Esta investigação centra-se na elaboração de um sistema que articula métricas de avaliação de desempenho a recursos e funcionalidades algorítmico-paramétricas, de maneira a permitir analisar e otimizar diferentes aspectos relativos ao grau de eficiência e às possibilidades de operação de configurações geométricas e algébricas de uma determinada área urbana. Neste âmbito, esta tese aborda o uso de recursos computacionais e ferramentas algorítmicas especificamente elaboradas para mensurar a performance de áreas urbanas, sob a perspectiva de princípios objetivamente mensuráveis do Desenvolvimento Orientado pelo Transporte (DOT), um modelo de desenvolvimento urbano que visa a cidades mais autônomas e mais sustentáveis. Mais especificamente, a presente pesquisa visa a verificar como atributos mensuráveis, geométricos e algébricos (e, portanto, programáveis) do DOT podem ser implementados por meio de um modelo computacional que utiliza métodos de otimização para dar suporte à tomada de decisão no processo de projetos urbanos. Assim, este trabalho é orientado no sentido da elaboração de um sistema que possa ser integrado a processos de projeto urbano, fornecendo suporte à organização de bairros e cidades e contribuindo para o aprimoramento das possibilidades de análise e proposição em contextos urbanísticos. / This research focuses on the development of a system that articulates performance evaluation metrics to algorithmic-parametric features and functionalities, in order to analyze and optimize different aspects related to the degree of efficiency and to the possibilities of operation of geometric and algebraic configurations of a given urban area. In this context, this thesis deals with the use of computational resources and algorithmic tools specifically designed to assess the performance of urban areas, from the perspective of objectively measurable principles of Transit Oriented Development (TOD), an urban development model aimed at more autonomous and sustainable cities. More specifically, the present research aims at verifying how TOD's measurable, geometric and algebraic (and therefore programmable) attributes can be implemented through a computational model that uses optimization methods to support decision making in urban design processes. Thus, this work is oriented toward the elaboration of a system that can be integrated to urban design processes, providing support to the organization of neighborhoods and cities and contributing to the improvement of analysis and proposition possibilities in urbanistic contexts.

This master’s thesis is focused on optimization of rear wing of sport car by using open-source software. The optimization of 2D profile of the rear wing is present in this thesis. Python environment was chosen for optimization and evolutionary algorithm was is used as optimization function. This algorithm is further connected to Xfoil software, which is computing aerodynamic characteristic. The ratio of the lift and drag coefficients (C_L/C_D) is chosen as parameter which considers the aerodynamic efficiency. The CFD computation of flowing around the whole car is provided in open-source software OpenFOAM. . The profile optimization results to approximately 7.9 % raise of the parameter C_L/C_D, in the same wing stability. The main benefit of this work is to use open-source software for the optimization and CFD analysis, which in future might save company’s resources by not buying expensive commercial software licenses.

Grafomotorick© obt­e (GD) vraznÄ ovlivuj­ kvalitu ivota koln­m vÄkem poÄ­naj­c, kde se vyv­jej­ grafomotorick© schopnosti, a do dchodov©ho vÄku. VÄasn diagnza tÄchto obt­­ a terapeutick zsah maj­ velk vznam k jejich zlepen­. Vzhledem k tomu, e GD souvis­ z v­cermi symptomy v oblasti kinematiky, zkladn­ kinematick© parametry jako rychlost, zrychlen­ a vih prokzaly efektivn­ kvantizaci tÄchto symptom. Objektivn­ vpoÄetn­ syst©m podpory rozhodovn­ pro identifikaci a vyeten­ GD vak nen­ dostupn. A proto je hlavn­m c­lem m© disertaÄn­ prce vzkum pokroÄil© metody parametrizace online p­sma pro analzu GD se speciln­m zamÄen­m na vyuit­ metod zlomkov©ho kalkulu. Tato prce je prvn­, kter experimentuje s vyuit­m derivac­ neceloÄ­seln©ho du (FD) pro analzu GD pomoc­ online p­sma z­skan©ho od pacient s Parkinsonovou nemoc­ a u dÄt­ koln­ho vÄku. Byla navrena a evaluovna nov metoda parametrizace online p­sma zaloena na FD vyuit­m Grnwald-Letnikova p­stupu. Bylo dokzno, e navren metoda vznamnÄ zlepuje diskriminaÄn­ s­lu a deskriptivn­ schopnosti v oblasti Parkinsonick© dysgrafie. StejnÄ tak metoda pozitivnÄ ovlivnila i nejmodernÄj­ techniky v oblasti analzy GD u dÄt­ koln­ho vÄku. Vyvinut parametrizace byla optimalizovna s ohledem na vpoÄetn­ nroÄnost (a o 80 %) a tak© na vyladÄn­ du FD. Ke konci prce byly porovnny v­cer© p­stupy vpoÄtu FD, jmenovitÄ Riemann-Liouvillv, Caputv spoleÄnÄ z Grnwald-Letnikovm p­stupem za Äelem identifikace tÄch nejvhodnÄj­ch pro jednotliv© oblasti analzy GD.

Cette thèse de doctorat aborde spécifiquement le problème de la métamorphose entre différents maillages 3D, qui peut assurer un niveau élevé de qualité pour la séquence de transition, qui devrait être aussi lisse et progressive que possible, cohérente par rapport à la géométrie et la topologie, et visuellement agréable. Les différentes étapes impliquées dans le processus de transformation sont développées dans cette thèse. Nos premières contributions concernent deux approches différentes des paramétrisations: un algorithme de mappage barycentrique basé sur la préservation des rapports de longueur et une technique de paramétrisation sphérique, exploitant la courbure Gaussien. L'évaluation expérimentale, effectuées sur des modèles 3D de formes variées, démontré une amélioration considérable en termes de distorsion maillage pour les deux méthodes. Afin d’aligner les caractéristiques des deux modèles d'entrée, nous avons considéré une technique de déformation basée sur la fonction radial CTPS C2a approprié pour déformer le mappage dans le domaine paramétrique et maintenir un mappage valide a travers le processus de mouvement. La dernière contribution consiste d’une une nouvelle méthode qui construit un pseudo metamaillage qui évite l'exécution et le suivi des intersections d’arêtes comme rencontrées dans l'état-of-the-art. En outre, notre méthode permet de réduire de manière drastique le nombre de sommets normalement nécessaires dans une structure supermesh. Le cadre générale de métamorphose a été intégré dans une application prototype de morphing qui permet à l'utilisateur d'opérer de façon interactive avec des modèles 3D et de contrôler chaque étape du processus / This Ph.D. thesis specifically deals with the issue of metamorphosis of 3D objects represented as 3D triangular meshes. The objective is to elaborate a complete 3D mesh morphing methodology which ensures high quality transition sequences, smooth and gradual, consistent with respect to both geometry and topology, and visually pleasant. Our first contributions concern the two different approaches of parameterization: a new barycentric mapping algorithm based on the preservation of the mesh length ratios, and a spherical parameterization technique, exploiting a Gaussian curvature criterion. The experimental evaluation, carried out on 3D models of various shapes, demonstrated a considerably improvement in terms of mesh distortion for both methods. In order to align the features of the two input models, we have considered a warping technique based on the CTPS C2a radial basis function suitable to deform the models embeddings in the parametric domain maintaining a valid mapping through the entire movement process. We show how this technique has to be adapted in order to warp meshes specified in the parametric domains. A final contribution consists of a novel algorithm for constructing a pseudo-metamesh that avoids the complex process of edge intersections encountered in the state-of-the-art. The obtained mesh structure is characterized by a small number of vertices and it is able to approximate both the source and target shapes. The entire mesh morphing framework has been integrated in an interactive application that allows the user to control and visualize all the stages of the morphing process

We focus on the Tensor Product Structure (TPS) of the Hilbert space and the fact that a choice in the TPS has an impact on the representation of the studied quantum system. We define the measurement problem in quantum mechanics and present some theories about quantum mechanics, each of them highlighting a different approach to quantum measurements. Then, a new approach to quantum measurement is presented by considering it as a change in the Tensor Product Structure of the Hilbert space associated with the description of a system. The system is made of a physical quantum system entangled with a measurement device. The description of the system changes to a new one where there is no entanglement anymore between the physical system and the measurement apparatus. The change in the TPS is performed using a global unitary transformation and more precisely by diagonalizing the density matrix of the system using unitary matrices. Four sets of matrices are obtained, each of them diagonalizing the density matrix in a different way for our toy model made of 2 qubits. Then, we want to recover Born’s rule directly from the diagonalizing matrices by measuring the size of their sets using Haar measure. We have not been able to conclude this program, but we outline what is expected to happen such that standard probabilities can be recovered.

In the past decade, characterizing spiking neuron models has been extensively researched as an essential issue in computational neuroscience. In this thesis, we examine the estimation problem of two different neuron models. In Chapter 2, We propose a modified Izhikevich model with an adaptive threshold. In our two-stage estimation approach, a linear least squares method and a linear model of the threshold are derived to predict the location of neuronal spikes. However, desired results are not obtained and the predicted model is unsuccessful in duplicating the spike locations. Chapter 3 is focused on the parameter estimation problem of a multi-timescale adaptive threshold (MAT) neuronal model. Using the dynamics of a non-resetting leaky integrator equipped with an adaptive threshold, a constrained iterative linear least squares method is implemented to fit the model to the reference data. Through manipulation of the system dynamics, the threshold voltage can be obtained as a realizable model that is linear in the unknown parameters. This linearly parametrized realizable model is then utilized inside a prediction error based framework to identify the threshold parameters with the purpose of predicting single neuron precise firing times. This estimation scheme is evaluated using both synthetic data obtained from an exact model as well as the experimental data obtained from in vitro rat somatosensory cortical neurons. Results show the ability of this approach to fit the MAT model to different types of reference data.

Numerous prediction models of SARS-CoV-2 pandemic were proposed in the past. Unknown parameters of these models are often estimated based on observational data. However, lag in case-reporting, changing testing policy or incompleteness of data lead to biased estimates. Moreover, parametrization is time-dependent due to changing age-structures, emerging virus variants, non-pharmaceutical interventions, and vaccination programs. To cover these aspects, we propose a principled approach to parametrize a SIR-type epidemiologic model by embedding it as a hidden layer into an input-output non-linear dynamical system (IO-NLDS). Observable data are coupled to hidden states of the model by appropriate data models considering possible biases of the data. This includes data issues such as known delays or biases in reporting. We estimate model parameters including their time-dependence by a Bayesian knowledge synthesis process considering parameter ranges derived from external studies as prior information. We applied this approach on a specific SIR-type model and data of Germany and Saxony demonstrating good prediction performances. Our approach can estimate and compare the relative effectiveness of non-pharmaceutical interventions and provide scenarios of the future course of the epidemic under specified conditions. It can be translated to other data sets, i.e., other countries and other SIR-type models.