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Flank margin caves of the Bahamas are formed by mixing dissolution in a fresh-water lens. As they evolve, the probability of intersecting neighboring voids increases, and they enlarge in a nonlinear fashion. Large flank margin caves become constrained by surface topography and their morphology is influenced by the shape of the enclosing land mass as a result. High phreatic ceilings can be dissolved if the fresh-water lens is distorted by lithological heterogeneities or hydrologic loading due to storm events. Early diagenesis of the host rock causes the reorganization of porosity and permeability through dissolution and cementation processes. Meteoric overprinting occurs but cannot be used as a tool in determining the age of eolianites or the climatic conditions at the time of deposition. Current evidence indicates an OIS 5e speleogenesis of large flank margin caves. An OIS 11 origin can be advanced only with compelling evidence of a pre-OIS 5e highstand.

This thesis deals with quantifying the merits of Distributed Maximum Power Point Tracking (DMPPT), as well as providing solutions to achieve DMPPT in PV systems. A general method based on 3D modeling is developed to determine the energy yield of PV installations exploiting different levels of DMPPT granularity. Sub-string-level DMPPT is shown to have up to 30% more annual energy yield than panel-level DMPPT. A Multi-Input-Single-Output (MISO) dc-dc converter is proposed to achieve DMPPT in parallel-connected applications. A digital current-mode controller is used to operate the MISO converter in pseudo-CCM mode. For series-connected applications, the virtualparallel concept is introduced to utilize the robustness of the parallel connection. This concept is demonstrated on a three-phase boost converter. The topology offers reduced output voltage ripple under shading which increases the life-time of the output capacitor. The prototypes yield output power benefits of up to 46% and 20% for the tested shading conditions.

Cette thèse a pour but de contribuer à l'étude des réservoirs carbonatés karstiques par une approche intégrant modélisation géologique numérique 3D et hydrogéologie. Une méthodologie originale a été ainsi développée pour être appliquée à la caractérisation des ressources en eau souterraine de l'Unité du Beausset (Bouches-du-Rhône et Var, SE France). Cette méthodologie lie l'architecture géologique 3D du réservoir à ses propriétés hydrodynamiques extraites de son étude hydrogéologique. Cette zone est un synclinal de roches sédimentaires mésozoïques d'une épaisseur pouvant atteindre 3000m. Ces roches affleurent sur environ 650 km², et ont subi de nombreuses phases de fracturation et karstification. A partir de la synthèse des données existantes géologiques, hydrogéologiques et karstologiques, sept intervalles lithostratigraphiques ont été définis. Ces intervalles ont également été caractérisés hydrodynamiquement par l'analyse des séries temporelles de hauteur, température et conductivité électrique enregistrées en continu en sept sources représentatives. Cette caractérisation a été complétée par des campagnes exhaustives d'hydrochimie et de mesures de débit. L'ensemble des données et des résultats obtenus ont permis de définir où sont les unités de stockages et d'écoulement de l'eau souterraine. Ces dernières ont été intégrées de manière qualitative en 3D à l'aide d'un modèle surfacique de l'architecture géologique de l'Unité du Beausset. Cette intégration a permis de définir les meilleures zones de captage potentiel pour de nouvelles ressources en eau souterraine. / The aim of this PhD thesis is to provide an original approach for the characterization of karstic carbonate reservoirs that integrates 3D geological modeling and hydrodynamics. The 3D geological model stands for the structural compartmentalization of the reservoir and the hydrodynamics provide dynamic properties for the understanding of the fluid flow. This methodology is applied to the characterization of the groundwater resources of the Beausset Unit (SE France). The study area is a syncline composed of nearly 3000 m of Mesozoic sedimentary rocks, which age from late Triassic to Upper Cretaceous. These rocks, which are mainly carbonates, crop out over an area of 650 km² and have known several phases of fracturation and karstification. This study is divided in four parts: (1) synthesis of existing data, (2) 3D geological modeling, (3) study of hydrodynamics, and (4) integration of static and dynamic data in order to discuss the characterization of the groundwater resources in the Beausset Unit. The existing data on stratigraphy, lithology, petrophysical properties, karstology and hydrogeology allow the definition of seven lithostratigraphic intervals that have been chosen for modeling. These intervals represent the vertical compartmentalization of the reservoir: each interval has a unique combination of karst and rocks properties. The integration of all this data end results leads to the recognition of the flow and reservoir units in each lithostratigraphic interval. A qualitative link has been made between the 3D architecture of the basin and the reservoir properties; it allows the characterization of the best potential targets for new groundwater tapping zones.

A obtenção e a reconstrução da geometria tridimensional (3D) de objetos e ambientes têm importância crescente em áreas como visão computacional e computação gráfica. As formas atuais de obtenção e reconstrução 3D necessitam de equipamentos e montagens sofisticadas que, por conseqüência, têm custos elevados e aplicação limitada. Este trabalho apresenta criticamente os principais algoritmos para a reconstrução 3D a partir de par de imagens estéreo e identifica os mais viáveis para utilização com equipamentos convencionais. Por meio da implementação de alguns destes algoritmos, da comparação dos resultados obtidos em sua execução e também pela comparação com os resultados encontrados na literatura, são identificadas as principais deficiências. São propostas adequações aos algoritmos existentes, em particular, é apresentada a proposta da técnica das faixas que proporciona a redução drástica no consumo de memória para o processamento da geometria 3D e que possui desempenho computacional melhor em relação às técnicas tradicionais. Foi implementado um protótipo de sistema de reconstrução 3D que permite a reconstrução pelas diferentes técnicas estudadas e propostas, bem como permite visualizar o cenário reconstruído sob diferentes pontos de vista de forma interativa. / The acquisition and reconstruction of three-dimensional (3D) geometry of objects and environments have their importance growing in areas such as Computer Vision and Computer Graphics. The current methods to acquire and reconstruct three-dimensional data need sophisticated equipments and assemblies, which have expensive costs and limited applications. This work presents the main algorithms for 3D reconstruction using a pair of stereo images and identifies which are viable to use with conventional equipments. Through the implementation of some of these algorithms, by comparing the results obtained and comparing with the results presented in the literature, the main limitations were identified. This work proposes adjustments in the existing algorithms, in particular it proposes the stripping technique, which provides a huge memory usage reduction for 3D geometry processing and better computing performance if compared with traditional approaches. A prototype system for 3D reconstruction was implemented, which allows the reconstruction using the different researched and proposed techniques and allows interactive visualization of the reconstructed scene in different angles.

L'utilisation des structures sandwichs composées d’âme en nid d'abeilles et de peaux a considérablement augmenté ces dernières années dans plusieurs secteurs industriels tels que l’aéronautique, l’aérospatiale, le navale et l’automobile. Cet intérêt croissant pour ces matériaux alvéolaires est principalement lié à leur faible densité et meilleur rapport masse/rigidité/résistance en comparaison avec les alliages métalliques ou les matériaux composites classiques. Cependant, leur constitution rend souvent les opérations de mise en forme par usinage compliquées et difficile à mener à cause de l’usure prématurée des outils coupants et l’endommagement important induit en subsurface des pièces. En effet, les vibrations importantes des parois minces du nid d’abeilles sont une source de plusieurs problèmes comme la mauvaise qualité des surfaces usinées, les fibres non coupées, délaminage, défauts, etc. Les travaux de cette thèse s’intéressent à la compréhension du comportement des structures nids d’abeilles composite (Nomex®) et métallique (aluminium) en usinage. L’enlèvement de matière par fraisage présente pour ces matériaux plusieurs verrous scientifiques et technologiques. Une analyse expérimentale a permis d’identifier dans un premier temps les phénomènes physiques mis en jeu lors de la formation des copeaux et les interactions entre les arêtes de coupe et les parois minces des cellules de la structure alvéolaire. Un intérêt particulier a été porté sur la caractérisation des défauts induits dans le matériau par les différentes parties composant la fraise, le déchiqueteur et le coteau. Deux protocoles expérimentaux ont été mis en place afin de qualifier la qualité et l’intégrité des surfaces usinées. Ils tiennent compte de la particularité des âmes en nid d'abeilles : composite ou métallique, leur géométrie alvéolaire, leur densité et l’épaisseur fine des parois. Un nouveau critère de qualité a été établi et proposé en tant qu’indicateur d’endommagement pour le suivi de l’état des surfaces alvéolaires fraichement usinées. Basée sur l’analyse statistique de Taguchi, une hiérarchisation des paramètres d’usinage et leur influence sur le comportement de ces matériaux ont été ensuite réalisées. Par ailleurs, l’usure des outils de coupe a été étudiée selon le couple outil-matériau usiné et les conditions de fraisage choisies. Comme l’a montré l’étude expérimentale, l’optimisation des paramètres d’usinage via une approche expérimentale seule est souvent longue et coûteuse. La simulation numérique peut apporter une aide complémentaire et constituer un outil intéressant pour l’analyse de la physique de la coupe des nids d’abeilles. Dans cette optique et en deuxième partie de la thèse, un modèle numérique par éléments finis a été spécifiquement développé pour la simulation du fraisage 3D des matériaux nids d’abeilles. Pour le Nomex®, deux lois de comportement mécanique couplées avec l’endommagement ont été identifiées et implémentées via la subroutine VUMAT dans Abaqus explicit. Pour simuler la formation des copeaux, deux critères de rupture (Hashin et Tsai-Wu) avec chute de rigidité ont été exploités. Les résultats du calcul numérique et ceux des essais expérimentaux ont montré une bonne concordance en termes de mécanismes de formation des copeaux, d’efforts de coupe et de modes d’endommagement / The use of sandwich structures made with honeycomb core and skins has considerably increased these last years in several industrial sectors such as aeronautics, aerospace, naval and automotive. This growing interest for the alveolar materials is mainly related to their low density and better mass/stiffness/strength ratio compared to metal alloys or conventional composites. However, their constitution makes machining operations complicated and difficult to control because of the premature cutting tool wear and the significant damage induced in the workpiece. In fact, the important vibrations of the thin honeycomb walls are a source of several problems such as the poor surface quality, uncut fibers, delamination, defects, etc. This work deals with the understanding of the honeycomb composites behavior and metallic during machining. The material removal process by milling of these materials presents several scientific and technological challenges. Firstly, an experimental analysis has been used to identify the physical phenomena involved during the chip formation process and generated by the interactions between the cutting edge and the honeycomb cell walls. A particular interest was focused on the characterization of defects induced in the material by different parts of the cutter, the shredder and the saw blade. Two experimental protocols have been set up to qualify the quality and integrity of the machined surface. They consider the particularity of the honeycomb cores: composite or metallic, their geometry, and the thin wall thickness. A new quality criterion has been established and proposed as a damage indicator to monitoring the machining process and choice optimal cutting conditions. Based on Taguchi's statistical analysis, a hierarchy of the machining parameters and their influence on the behavior of these materials have then realized. In addition, the wear of cutting tools has been studied according to the selected tool-material couple and milling conditions. The optimization of machining parameters is often long and expensive only via experimental approach. Modelling and numerical simulation can provide complementary support with an interesting numerical tool to analyze the physics of cutting honeycombs. In this perspective and in the second part of the PhD thesis, a finite element numerical model has been especially developed for the 3D milling operation. For Nomex®, two coupled mechanical-damage behavior laws have been identified and implemented in Abaqus explicit subroutine VUMAT. To simulate the chip formation process and induced subsurface damage, two fracture criteria (Hashin and Tsai-Wu) with stiffness degradation concept have been operated. The comparison between the numerical simulation results and experimental data shows a good agreement in terms of the chip formation mechanisms, cutting forces and damage modes

A obtenção e a reconstrução da geometria tridimensional (3D) de objetos e ambientes têm importância crescente em áreas como visão computacional e computação gráfica. As formas atuais de obtenção e reconstrução 3D necessitam de equipamentos e montagens sofisticadas que, por conseqüência, têm custos elevados e aplicação limitada. Este trabalho apresenta criticamente os principais algoritmos para a reconstrução 3D a partir de par de imagens estéreo e identifica os mais viáveis para utilização com equipamentos convencionais. Por meio da implementação de alguns destes algoritmos, da comparação dos resultados obtidos em sua execução e também pela comparação com os resultados encontrados na literatura, são identificadas as principais deficiências. São propostas adequações aos algoritmos existentes, em particular, é apresentada a proposta da técnica das faixas que proporciona a redução drástica no consumo de memória para o processamento da geometria 3D e que possui desempenho computacional melhor em relação às técnicas tradicionais. Foi implementado um protótipo de sistema de reconstrução 3D que permite a reconstrução pelas diferentes técnicas estudadas e propostas, bem como permite visualizar o cenário reconstruído sob diferentes pontos de vista de forma interativa. / The acquisition and reconstruction of three-dimensional (3D) geometry of objects and environments have their importance growing in areas such as Computer Vision and Computer Graphics. The current methods to acquire and reconstruct three-dimensional data need sophisticated equipments and assemblies, which have expensive costs and limited applications. This work presents the main algorithms for 3D reconstruction using a pair of stereo images and identifies which are viable to use with conventional equipments. Through the implementation of some of these algorithms, by comparing the results obtained and comparing with the results presented in the literature, the main limitations were identified. This work proposes adjustments in the existing algorithms, in particular it proposes the stripping technique, which provides a huge memory usage reduction for 3D geometry processing and better computing performance if compared with traditional approaches. A prototype system for 3D reconstruction was implemented, which allows the reconstruction using the different researched and proposed techniques and allows interactive visualization of the reconstructed scene in different angles.

<p>Denna rapport tar upp teorier och metoder kring användbarhet i skapandet av en Flash-applikation. Rapporten beskriver steg för steg i skapandeprocessen, hela vägen från att ta fram behov och användningsområde till att skapa innehållet och slutligen en utförlig redogörelse för hur applikationen sammansätts. Metoderna som använts är huvudsakligen ITK (Identity Tool Kit) och scenarier enligt Alan Cooper. Vidare har metoder för hopsättning och visualisering av applikationen använts med stöd av Nielsen och Raskins användbarhetsprinciper. Resultatet visar att för att använda ITK i syfte att kartlägga en verksamhet, kräver detta en stor förståelse och modifikation av denna. Det visar också att Alan Coopers teorier om scenarier inte heller kommer till sin rätt utan en utförlig analys av användarna i denna. Resultatet visar även att med hjälp av programvarorna 3D studio Max och Flash kan interaktivt innehåll för produktvisualisering på nätet skapas med goda resultat.</p> / <p>This report addresses the theories and methods of usability in creating a Flash application. The report describes step by step in the creative process, all the way from the development needs and use to create content and finally a detailed explanation of how the application assemblies. The methods used are mainly ITK (Identity Tool Kit) and scenarios according to Alan Cooper. Furthermore, methods of assembly and visualization of application used with the support of Nielsen and Raskin usability principles. The result shows that the use of ITK in order to identify an activity, this requires a great understanding and modification of this. It also shows that Alan Cooper's theories about the scenarios do not come into its own, without a detailed analysis of the users thereof. The results also show that using the software 3D Studio Max and Flash for interactive content for product visualization on the web is created with good results.</p>

The following work explores the role of 3D printing in biological anthropology. A case study approach is used to provide an understanding of two different applications for 3D printing and to identify a potential methodology for creating 3D models. Case study one looks at the application of 3D printing to reconstruction projects using a flowerpot to test the reconstruction methodology. The second case study uses both laser surface and CT scanning to create a replica of a human skeleton. The two methods of data acquisition are evaluated for advantages and limitations in creating the virtual model. This work shows that there is a role for 3D printing in biological anthropology, but that data acquisition and processing issues are the most significant limiting factors in producing skeletal replicas. / October 2006

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