Introdução: O uso de telas de polipropileno para reforço em cirurgias para correção de prolapso vaginal apresenta taxas de complicação de até 25%. Trata-se de doença de alta prevalência, acometendo até 30% das mulheres, cujas opções atuais de tratamento foram reduzidas após a descontinuação da fabricação dos reforços tradicionais por diversos fabricantes. Uma alternativa é a utilização de matrizes sintéticas de outros materiais e com outras configurações, possibilitando inclusive cultura de células em seu leito. A eletrofiação possibilita a produção e reprodução em larga escala dessas matrizes a partir de polímeros solúveis expostos a um campo elétrico. Objetivos: Estabelecer parâmetros de produção de matrizes com fibras híbridas e randômicas através de eletrofiação, demonstrar sua reprodutibilidade e implantar tal tecnologia em solo brasileiro. Testar as seguintes características teóricas das matrizes híbridas produzidas com acido polilático (PLLA): maior força tênsil nos testes biomecânicos e biocompatibilidade mantida para cultura celular. Estudar a influência da cultura de células-tronco mesenquimais derivadas de adipócitos (CTDA) sobre as propriedades mecânicas das matrizes estudadas. Avaliar a influência da hidrólise na perda de força tênsil das matrizes em experimentos de até 90 dias. Métodos: Foram produzidas matrizes de PLLA dissolvidos em diclorometano (DCM) nas configurações de fibras randômicas, alinhadas e um novo método foi desenvolvido para produção de matrizes híbridas. Foram realizados microscopia eletrônica, testes biomecânicos, testes de atividade metabólica e biocompatibilidade com cultivo de células-tronco derivadas de adipócitos, além de testes de degradação em meio de cultura por 90 dias para comparar as matrizes. Análise de variância (ANOVA) com teste de Tukey foram utilizados para comparação dos resultados obtidos nos experimentos quando aplicáveis. Resultados: A produção de matrizes híbridas foi possível ajustando-se os parâmetros de eletrofiação. Imagens de microscopia comprovaram o alinhamento e hibridização das fibras. Testes uniaxiais mostraram que as matrizes híbridas foram 3 a 4 vezes mais resistentes a tração do que as matrizes randômicas (p < 0,0001) preservando sua biocompatibilidade e afinidade celular. A incorporação de células às matrizes híbridas e o experimento de degradação mostraram quedas nas propriedades mecânicas de força tênsil máxima das matrizes híbridas a partir de 14 dias em meio de cultura, mas sempre se mantendo acima das propriedades dos tecidos nativos pelo período estudado de até 90 dias. Conclusões: Foi possível o desenvolvimento de nova técnica de eletrofiação para produção de matrizes híbridas de fibras alinhadas e randômicas com maior força tênsil, ainda sim mantendo sua afinidade celular. Tais matrizes enfraqueceram no período de 90 dias estudado, sem contudo apresentar valores abaixo dos fisiológicos, mostrando-se como opção promissora para substituição de telas de polipropileno em clínica. Estudos com animais são necessários para confirmar essa hipótese / Introduction: Traditional reinforcement techniques for pelvic organ prolapse use mainly polypropylene meshes with complication rates up to 25%. It is a common disease with prevalence up to 30%, with reduced options of treatment after withdrawing of major companies from this market. An alternative is the use of synthetic matrices from other materials with other configurations, possibly with cell culture added. Electrospinning is a reproducible technique that uses solved polymers exposed to intense electric field to produce sheets like that. Objectives: Establish parameters to electrospin hybrid and random fibres and setup this technology in Brazil. Prove following theoretical characteristics of hybrid poly- L-lactide (PLLA) matrices: higher tensile strength in biomechanical tests with comparable biocompatibility. Study adipose derived stem cells (ADSC) culture impact over biomechanical properties of these matrices. Check hydrolysis influences on tensile strength up to 90 days. Methods: PLLA solved in dichloromethane (DCM) was electrospun in random fibres, align fibres and a novel method was developed to produce hybrid fibres. Electron microscopy (SEM), biomechanical tests, metabolic activity and biocompatibility with adipose-derived stem cells and additionally, degradation test up to 90 days in culture medium were performed to compare matrices. ANOVA with Tukey test of differences was used to compare experiment results. Results: The production of hybrid matrices was possible adjusting electrospinning parameters, SEM confirmed fibre\'s alignment and hybridization, uniaxial tests showed that hybrid matrices were 3 to 4 times stronger than random ones (p < 0,0001) maintaining its biocompatibility and cell affinity. Both cell incorporation to hybrid matrices and degradation experiment showed mechanical properties drop (ultimate tensile strength) after 14 days in culture medium but always keeping it above physiologic range up to 90 days studied. Conclusions: Development of new technique of electrospinning of hybrid matrices of align and random fibres was possible, with higher tensile strength and keeping the same cell affinity. These matrices showed drop in mechanical strength along 90 days of study but always above the natural tissues range being a promising option to polypropylene meshes in clinic. Further studies with animals are needed to confirm this hypothesis

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.

The aim for this thesis is to develop a foundation for a compression system for animated mesh sequences, specifically under dynamic change of mesh geometry and topology. Compression of mesh sequences is of special interest in the game industry and this particular thesis is a part of an ongoing series of projects at EA DICE. One of the primary challenges when creating a mesh compression system is creating a matching bijective subset of the mesh surfaces between two subsequent frames in the animation to guide remeshing of the sequence. This thesis describes a method for producing a bijective set of matching mesh patches between two meshes along with an error metric that captures the quality of the matching in terms of shape similarity and distortion. Theory of mathematical topology and tensor algebra used in methods for high performance scientific digital 3D-image recognition are here adopted to extract similar local features between meshes. Techniques for creating parametrizations of mesh patches are combined with techniques for matching point clouds and deforming mesh geometry under energy minimization in order to produce a matching set of patches. The presented algorithm successfully creates bijective sets of matched patches for subsequent meshes in a sequence as well as measures the error for the matchings. Results show an average matching set size of approximately 25% of the mesh areas over a sequence of meshes. This suggests that the data size of such a sequence could potentially be reduced by 25%.

Avec le développement important des techniques d’animation, les maillages animés sont devenus un sujet de recherche important en informatique graphique, comme la segmentation de maillages animés ou la compression. Ces maillages animés qui sont créés à l’aide de logiciels ou à partir de données de capture de mouvements sont composés d’une séquence ordonnée de maillages de forme statique et dont la topologie reste la même (nombre fixe de sommets et de triangles). Bien qu’un grand nombre de travaux ont été menés sur les maillages statiques durant les deux dernières décennies, le traitement et la compression de maillages animés présentent de nombreuses difficultés techniques. En particulier, les traitements de maillages dynamiques nécessitent une représentation de données efficace basée sur la segmentation. Plusieurs travaux ont été publiés par le passé et qui permettent de segmenter un maillage animé en un ensemble de composants rigides.Dans cette thèse, nous présentons plusieurs techniques qui permettent de calculer une segmentation spatio-temporelle d’un maillage animé ; de tels travaux n’ont pas encore été publiés sur ce sujet. De plus, nous avons étendu cette méthode pour pouvoir comparer ces maillages animés entre eux à l’aide d’une métrique. À notre connaissance, aucune méthode existante ne permet de comparer des maillages animés entre eux. / With an abundance of animation techniques available today, animated mesh has become a subject of various data processing techniques in Computer Graphics community, such as mesh segmentation and compression. Created from animation software or from motion capture data, a large portion of the animated meshes are deforming meshes, i.e. ordered sequences of static meshes whose topology is fixed (fixed number of vertices and fixed connectivity). Although a great deal of research on static meshes has been reported in the last two decades, the analysis, retrieval or compressions of deforming meshes remain as new research challenges. Such tasks require efficient representations of animated meshes, such as segmentation. Several spatial segmentation methods based on the movements of each vertex, or each triangle, have been presented in existing works that partition a given deforming mesh into rigid components. In this thesis, we present segmentation techniques that compute the temporal and spatio-temporal segmentation for deforming meshes, which both have not been studied before. We further extend the segmentation results towards the application of motion similarity measurement between deforming meshes. This may be significant as it solves the problem that cannot be handled by current approaches.

Ce manuscrit est dédié à la détection et la caractérisation de points d'intérêt dans les maillages. Nous montrons tout d'abord les limitations de la mesure de courbure sur des contours francs, mesure habituellement utilisée dans le domaine de l'analyse de maillages. Nous présentons ensuite une généralisation de l'opérateur SUSAN pour les maillages, nommé SUSAN-3D. La mesure de saillance proposée quantifie les variations locales de la surface et classe directement les points analysés en cinq catégories : saillant, crête, plat, vallée et creux. Les maillages considérés sont à variété uniforme avec ou sans bords et peuvent être réguliers ou irréguliers, denses ou non et bruités ou non. Nous étudions ensuite les performances de SUSAN-3D en les comparant à celles de deux opérateurs de courbure : l'opérateur de Meyer et l'opérateur de Stokely. Deux méthodes de comparaison des mesures de saillance et courbure sont proposées et utilisées sur deux types d’objets : des sphères et des cubes. Les sphères permettent l'étude de la précision sur des surfaces différentiables et les cubes sur deux types de contours non-différentiables : les arêtes et les coins. Nous montrons au travers de ces études les avantages de notre méthode qui sont une forte répétabilité de la mesure, une faible sensibilité au bruit et la capacité d'analyser les surfaces peu denses. Enfin, nous présentons une extension multi-échelle et une automatisation de la détermination des échelles d'analyse qui font de SUSAN-3D un opérateur générique et autonome d’analyse et de caractérisation pour les maillages / This manuscript is dedicated to the detection and caracterization of interest points for 3D meshes. First of all, we show the limitations of the curvature measure on sharp edges, the measure usually used for the analysis of meshes. Then, we present a generalization of the SUSAN operator for meshes, named SUSAN-3D. The saliency measure proposed quantify the local variation of the surface and classify directly the analysed vertices in five classes: salient, crest, flat, valley and cavity. The meshes under consideration are manifolds and can be closed or non-closed, regulars or irregulars, dense or not and noised or not. The accuracy of the SUSAN-3D operator is compared to two curvature operators: the Meyer's operator and the Stokely's operator. Two comparison methods of saliency and curvature measures are described and used on two types of objects: spheres and cubes. The spheres allow the study of the accuracy for differentiable surfaces and the cubes for two types of sharp edges: crests and corners. Through these studies, we show the benefits of our method that are a strong repeatability of the measure, high robustness to noise and capacity to analyse non dense meshes. Finally, we present a multi-scale scheme and automation of the determination of the analysis scales that allow SUSAN-3D to be a general and autonomous operator for the analysis and caracterization of meshes

L'objectif de cette thèse est de développer un nouveau schéma numérique du type volumes finis pour la dynamique des gaz. Dans deux articles, F.Berthelin, T.Goudon et S.Minjeaud proposent de résoudre le système des équations d'Euler barotrope en dimension 1 d'espace, avec un schéma d'ordre 1 fonctionnant sur grilles décalées et dont la conception des flux est inspirée des schémas cinétiques. Nous proposons d'enrichir ce schéma afin qu'il puisse résoudre le système des équations d'Euler barotrope ou complet, en dimension 2 d'espace sur maillage cartésien ou non structuré, possiblement à l'ordre 2 et le cas échéant à bas nombres de Mach. Nous commencerons par développer une version 2D du schéma sur grilles cartésiennes (ou MAC) à l’ordre 2 via une méthode de type MUSCL, d'abord pour les équations barotropes puis pour les équations complètes. Ces dernières demandent de traiter une équation d’énergie supplémentaire et l’un des problèmes -résolu- est de trouver une définition discrète convenable de l’énergie totale telle qu'elle satisfasse une équation conservative locale. Dans un troisième chapitre nous étudierons le passage à la limite du compressible vers l'incompressible et nous verrons comment utiliser les atouts de notre schéma afin de le modifier et d'en faire un schéma Asymptotic Preserving pour des écoulements à bas nombres de Mach. Dans un quatrième temps nous proposerons une adaptation du schéma sur des maillages non structurés. Notre approche sera fortement inspirée des méthodes DDFV et pourra présenter des avantages dans les régimes à faibles nombres de Mach. Cette thèse se termine par un cinquième chapitre issu d’une collaboration lors du CEMRACS 2017, où le point de vue considéré n’est plus macroscopique mais microscopique. Nous commencerons par étudier un modèle micro/macro idéalisé auquel un processus stochastique a été ajouté puis nous tenterons d'en déduire un modèle à grande échelle pour un système fortement couplé, qui soit consistant avec la description micro/macro sous-jacente du problème physique. / The objective of this thesis is to develop a new numerical scheme of finite volume type for gas dynamics. In two articles, F.Berthelin, T.Goudon and S.Minjeaud propose to solve the barotropic Euler system in dimension 1 of space, with a first order scheme that works on staggered grids and of which fluxes are inspired by kinetic schemes. We propose to enhance this scheme so that it can solve the barotropic or complete Euler systems, in dimension 2 of space on Cartesian or unstructured grids, possibly at order 2 and at Low Mach numbers where appropriate. We begin with the development of a 2D version of the scheme on Cartesian (or MAC) grids, at order 2 via a MUSCL type method, for the barotropic equations at first and then for the complete equations. The latter require to handle with an additional energy equation and one of the -solved- problems is to find a suitable discrete definition of the total energy such that it satisfies a local conservative equation. In a third chapter we study the transition from the compressible case to the incompressible limit and we shall see how to use the advantages of our initial scheme in order to make it an Asymptotic Preserving scheme at low Mach numbers. In a fourth chapter we propose an adaptation of the scheme on unstructured meshes. Our approach is strongly inspired by the DDFV methods and may have advantages in low-Mach regimes.This thesis ends with a fifth chapter issued from a collaboration during CEMRACS 2017, where the considered point of view is no longer macroscopic but microscopic. We begin by studying a simplified micro/macro model with an added stochastic process and then we attempt to deduce a large-scale model for a strongly coupled system which has to be consistent with the underlying micro / macro description of the physical problem.

The paper presents a method for generating curved surfaces of 3D finite element meshes by mesh refinement starting with a very coarse grid. This is useful for parallel implementations where the finest meshes should be computed and not read from large files. The paper deals with simple geometries as sphere, cylinder, cone. But the method may be extended to more complicated geometries. (with 45 figures)

The paper deals with a combination of the Fourier-finite-element method with the Nitsche-finite-element method (as a mortar method). The approach is applied to the Dirichlet problem of the Poisson equation in three-dimensional axisymmetric domains $\widehat\Omega$ with non-axisymmetric data. The approximating Fourier method yields a splitting of the 3D-problem into 2D-problems. For solving the 2D-problems on the meridian plane $\Omega_a$, the Nitsche-finite-element method with non-matching meshes is applied. Some important properties of the approximation scheme are derived and the rate of convergence in some $H^1$-like norm is proved to be of the type ${\mathcal O}(h+N^{-1})$ ($h$: mesh size on $\Omega_a$, $N$: length of the Fourier sum) in case of a regular solution of the boundary value problem. Finally, some numerical results are presented.

The advent of industry 4.0 has not only brought innovation and automation with it but also new challenges. Automation in industrial settings is advancing at a rapid pace, thus making the modern industrial workplace all the more stimulating. Highly automated robots and machines work alongside humans in settings that seemed fictional some years ago. However, the shift to a smart industry has brought about certain safety concerns regarding whether the current safety systems can keep up with this ever-changing environment. Emergency stop buttons have long been the industry standard when it comes to classic safety precautions. Nevertheless, researchers examine several possibilities on how they can upgrade the already established safety systems. One such practice is to incorporate visibility as part of an emergency safety system. There has already been a proposal to use 2D visibility as an emergency safety protocol which has shown encouraging results. Thus, making a 3D approach as the logical next step. In this thesis work, a 3D visibility emergency stop system is presented, implemented,and tested. To begin with, a small review of how other researchers have tried to solve similar problems is done. Furthermore, several 3D graphics techniques used in the project are introduced and briefly analysed. Then, the implementation of the project is presented, breaking down each component. After the implementation is completed, several tests that aim to profile the program are performed and examined. In addition, the project is compared to the 2D solution that has already been proposed. The findings from the testing show that a 3D visibility approach is a viable and favourable option. The results reveal a promising outcome when it comes to object visibility as well as response swiftness.

El presente trabajo de investigación busca implementar una metodología de diseño de mallas de perforación y voladura en la empresa Minera Sotrami S.A, perteneciente al rubro de pequeña minería, con fines de estandarizarlo. La ejecución de dicha investigación se realiza mediante la utilización del algoritmo matemático de Holmberg que permite definir un modelo numérico para el diseño de una malla de perforación, y con la consideración de criterios operacionales encontrar una malla técnica que permita mejorar los rendimientos en las labores de exploración y desarrollo. Para el logro del mismo, se consideró como variable fija el tipo de roca (tipo III A) y las características geomecánicas presentes en ella; el diámetro del taladro de perforación como variable fija; y, el tipo de explosivo y accesorio de voladura como cambiantes, ya que se reemplazó la utilización de guías, mecha de seguridad y dinamita por el empleo de detonadores no eléctricos (Exaneles) y emulsiones encartuchadas. La oportuna y pertinente estandarización del proceso de perforación y voladura permitió obtener los siguientes resultados: el avance por disparo pasó a 1.62 m, el factor de carga se redujo a 13.46 kg/m y el factor de potencia disminuyo considerablemente. / This research work seeks to implement a design methodology for drilling and blasting meshes in the company Minera Sotrami S.A, belonging to the small mining sector, with finality to standardize it. This research is carried out by using the Holmberg mathematical algorithm that allows defining a numerical model for the design of a drilling mesh, and with the consideration of operational criteria, finding a technical mesh that allow improving the performance of exploration and development labors. To achieve it, the type of rock (type III - A) and the geomechanical characteristics present in it were considered as a fixed variable; the diameter of the drill as a fixed variable; the type blasting attachment and explosives as changeable, since the use of guides, safety wick and dynamite was replaced with the use of non electric detonators (Exaneles) and encapsulated emulsions. The opportune and pertinent standardization of the drilling and blasting process allowed obtaining the following results: the advance per shot was to 1.62 m, the load factor was reduced to 13.46 kg/m and the power factor decreased considerably. / Tesis