Background. Being able to modify virtual environments can create immersive experiences for video-game players. Storing data as volumetric scalar fields allows for highly modifiable 3D environments that can be converted into GPU-friendly triangles with isosurface algorithms. Using scalar fields and isosurface algorithms can be more computationally expensive and require more data than the more commonly used polygonal models. Objectives. The aim of this thesis is to explore solutions to modifying real-time 3D environments with isosurface algorithms. This will be done in two parts. First in terms of observing how modern games deal with storing scalar fields, researching which isosurface algorithms are being used and how they are being used in games. The second part is to create an application and limit the data storage required while still running at a real-time speed. Methods. There are two methods to achieve the aim. The first is to research and see which data structures and isosurface algorithms are being used in modern games and how they are utilized. The second method will be done by implementation. The implementation will use the GPU through compute shaders and use marching cubes as isosurface algorithm. It will utilize Christopher Dyken’s Histogram Pyramids for stream compaction. Two different versions will be implemented that differ in terms of what data types will be used for storage. The first using the data type char and the second int. Between these two versions, the runtime speed will be measured and compared on two different hardware configurations. Results. Finding good data on what algorithms games use is difficult. Modern games are using scalar fields in many different ways: Some allow almost complete modification of terrain, others only use it for a 3D environment. For data storage, octrees and chunks are two common ways to store the fields. Dual Contouring appears to be the primary isosurface algorithm being used based on the researched games. The results of the implementation were very fast and usable in real time environments for destruction of terrain on a large scale. The less storage intensive variation of this implementation(char) gave faster results on modern hardware but the opposite(int) was true on older hardware. Conclusions. Modifying scalar field terrain is done at a very large scale in modern games. The choice of using Dual Contouring or Marching Cubes depends on the use-case. For areas where sharp features can be important Dual Contouring is the preferred choice. Likely for these reasons Dual Contouring was found to be a popular choice in the studied games. For other areas, like many types of terrain, Marching Cubes is very fast, as can be seen in the implementation. By using the char version of the implementation, interacting with the environment in real-time is possible at high frame-rates.

Nesse trabalho, foi feito o tratamento e a análise de cubos de dados de 8 núcleos ativos de galáxias próximos, no óptico e no infravermelho. O tratamento e a análise de todos os cubos de dados foram feitos utilizando-se uma série de metodologias específicas, muitas das quais foram desenvolvidas nos últimos anos pelo grupo de trabalho do autor. A análise de todos os cubos de dados foi feita com quatro objetivos principais: análise da fenomenologia geral nos arredores do AGN com a Tomografia PCA; análise das populações estelares, da emissão térmica de poeira e do featureless continuum nos arredores do AGN com uma síntese espectral feita com o software Starlight; análise da cinemática estelar e do gás ao redor do buraco negro central e, em alguns casos, simulação com o objetivo de se determinar a massa do buraco negro; análise dos mecanismos de excitação e ionização do gás ou da emissão de hidrogênio molecular. / In this work, we have treated and analyzed data cubes of 8 nearby active galactic nuclei, in the optical and in the infrared. All data cube treatment and analysis were performed using a series of specific methodologies, many of which were developed in the last few years by the author\'s working group. The analysis of all data cubes was performed with four main objectives: analysis of the general phenomenology of the AGN environment, using PCA Tomography; analysis of the stellar populations, of the thermal emission from dust and of the featureless continuum in the vicinity of the AGN, with a spectral synthesis performed with the Starlight software; analysis of the stellar and gas kinematics around the central black hole and, in some cases, simulations with the purpose of determining the mass of the black hole; analysis of the excitation and ionization mechanisms of the gas or of the emission from molecular hydrogen.

Cerveja é uma bebida alcoólica mundialmente popular e a mais consumida no Brasil. Existem diversos estilos de cerveja no mundo, os quais são produzidos por modificações no processo de produção, no uso de diferentes ingredientes, na maturação utilizando barris de madeira e/ou adição de fragmentos de madeira, entre outros. A maturação em madeira pode proporcionar complexidade aromática às bebidas, sendo a madeira de carvalho amplamente utilizada para a maturação de bebidas alcoólicas. O uso dessa madeira na maturação da cerveja é o foco desse trabalho, que maturou cervejas a 0°C, durante três meses, em garrafas de vidro de 600 mL, barris de carvalho e recipientes plásticos com cubos de carvalho, na dose de 3g/L, provenientes de três níveis diferentes de tosta (leve, média, e alta). Das cervejas oriundas dos diferentes tratamentos, foram analisadas graduação alcoólica, pH, acidez total, turbidez, fenólicos totais, cor e amargor; os compostos voláteis (aldeídos, ésteres e álcoois superiores) foram analisados por Cromatografia gasosa (FID) e os compostos fenólicos de baixo peso molecular (ácido gálico, 5-hidroximetil-furfural, furfural, ácido vanílico, ácido siríngico, vanilina, siringaldeído, coniferaldeído e sinapaldeído) por Cromatografia líquida de alta eficiência (HPLC). As cervejas também foram analisadas sensorialmente mediante teste de preferência. A análise dos resultados mostrou que não houve alterações na qualidade da cerveja que pudessem ser atribuídas ao armazenamento com madeira. Os compostos voláteis tiveram pequenas alterações, por outro lado, os compostos fenólicos de baixo peso molecular foram os que apresentaram maiores incrementos no período de três meses de maturação. Não houve diferença na aceitação sensorial entre as cervejas maturadas com cubos de madeira, barril e em garrafas de vidro. Futuros estudos são necessários para que seja possível obter um produto de qualidade que possa satisfazer o consumidor e seja acessível à indústria. / Beer is a very popular alcoholic beverage in the world and the most widely consumed in Brazil. There are many styles of beer in the world that can be produced by changes in the production process, use of various ingredients, maturation using wood barrels and / or addition of wood fragments, and others. Wood maturation can provide aromatic complexity to alcoholic beverages, and the oak wood is widely used. The use of oak in the maturation of beer is the focus of this work. The beers matured at 0 °C for three months in glass bottles of 600 mL, oak barrels and plastic containers with oak cubes at a dose of 3g/L, with three different levels of toasting (light, medium, and high). Beers resulting from the different treatments were analyzed physico-chemically (alcohol content, pH, total acidity, turbidity, total phenolics, color and bitterness), the volatile compounds (aldehydes, esters and higher alcohols) by gas chromatography (FID), the low molecular weight phenolic compounds (gallic acid, 5-hydroxymethylfurfural, furfural, vanillic acid, syringic acid, vanillin, syringaldehyde, coniferaldehyde and sinapaldehyde) by High Performance Liquid Chromatography (HPLC), and sensory. The analysis shows that there were no qualities changes in beer that could be attributed to the storage in contact with oak wood. The volatile compounds had minor changes; the low molecular weight phenolic compounds were those with the greatest increases within three months of maturation. There was no difference in sensory acceptance between beers matured in oak barrel, oak cubes and glass bottles. This work suggests that wood influences sensory beer, but more studies are needed to be able to get a quality product that can satisfy the consumer and is accessible to the industry.

L'explosion du volume de données disponibles due au développement des technologies de l'information et de la communication a démocratisé les flots qui peuvent être définis comme des séquences non bornées de données très précises et circulant à grande vitesse. Les stocker intégralement est par définition impossible. Il est alors essentiel de proposer des techniques de résumé permettant une analyse a posteriori de cet historique. En outre, un grand nombre de flots de données présentent un caractère multidimensionnel et multiniveaux que très peu d'approches existantes exploitent. Ainsi, l'objectif de ces travaux est de proposer des méthodes de résumé exploitant ces spécificités multidimensionnelles et applicables dans un contexte dynamique. Nous nous intéressons à l'adaptation des techniques OLAP (On Line Analytical Processing ) et plus particulièrement, à l'exploitation des hiérarchies de données pour réaliser cette tâche. Pour aborder cette problématique, nous avons mis en place trois angles d'attaque. Tout d'abord, après avoir discuté et mis en évidence le manque de solutions satisfaisantes, nous proposons deux approches permettant de construire un cube de données alimenté par un flot. Le deuxième angle d'attaque concerne le couplage des approches d'extractions de motifs fréquents (itemsets et séquences) et l'utilisation des hiérarchies pour produire un résumé conservant les tendances d'un flot. Enfin, les catégories de hiérarchies existantes ne permettent pas d'exploiter les connaissances expertes dans le processus de généralisation. Nous pallions ce manque en définissant une nouvelle catégorie de hiérarchies, dites contextuelles, et en proposant une modélisation conceptuelle, graphique et logique d'un entrepôt de données intégrant ces hiérarchies contextuelles. Cette thèse s'inscrivant dans un projet ANR (MIDAS), une plateforme de démonstration intégrant les principales approches de résumé a été mise au point. En outre, la présence de partenaires industriels tels que Orange Labs ou EDF RD dans le projet a permis de confronter nos approches à des jeux de données réelles. / Due to the rapid increase of information and communication technologies, the amount of generated and available data exploded and a new kind of data, the stream data, appeared. One possible and common definition of data stream is an unbounded sequence of very precise data incoming at an high rate. Thus, it is impossible to store such a stream to perform a posteriori analysis. Moreover, more and more data streams concern multidimensional and multilevel data and very few approaches tackle these specificities. Thus, in this work, we proposed some practical and efficient solutions to deal with such particular data in a dynamic context. More specifically, we were interested in adapting OLAP (On Line Analytical Processing ) and hierarchy techniques to build relevant summaries of the data. First, after describing and discussing existent similar approaches, we have proposed two solutions to build more efficiently data cube on stream data. Second, we were interested in combining frequent patterns and the use of hierarchies to build a summary based on the main trends of the stream. Third, even if it exists a lot of types of hierarchies in the literature, none of them integrates the expert knowledge during the generalization phase. However, such an integration could be very relevant to build semantically richer summaries. We tackled this issue and have proposed a new type of hierarchies, namely the contextual hierarchies. We provide with this new type of hierarchies a new conceptual, graphical and logical data warehouse model, namely the contextual data warehouse. Finally, since this work was founded by the ANR through the MIDAS project and thus, we had evaluated our approaches on real datasets provided by the industrial partners of this project (e.g., Orange Labs or EDF R&D).

Den här uppsatsen handlar om tillverkningsprocessen av vad författaren har valt att kalla för ludvigkuber till delar i en gesällmöbel. Ludvigkuber är ett illusionsmönster av fanerbitar som bildar tredimensionella kuber. Mönstret har sitt ursprung från bland annat antikens Grekland men blev populärt under Ludvig XIV:s regeringstid. Syftet med uppsatsen är att undersöka tillverkningsprocessen av en traditionell metod och jämföra denna med en modern metod för att fastställa vilken av dessa som lämpar sig bäst vid tillverkningen av delar till en gesällmöbel. I uppsatsen beskrivs tillverkningen och användandet av två olika jiggar samt för-och nackdelar med dessa. Resultatet visar på fördelar med att använda sig av den moderna metoden just i det här fallet, men att den klassiska metoden med lite mer efterforskning och justeringar skulle lämpa sig att använda även till detta ändamål.

Le monde médical dispose de plus en plus de sources d'images différentes, non seulement pour réaliser un diagnostic mais aussi pour évaluer l'efficacité d'un traitement et pour être guidé dans les interventions chirurgicales. Parallèlement, le développement des techniques opératoires s'oriente vers la chirurgie non " à ciel ouvert ", notamment la coelioscopie, qui permet de diminuer les risques liés à l'intervention ainsi que le temps d'hospitalisation du patient. En revanche, elle rend moins intuitive la réalisation de l'acte chirurgical, notamment du fait de la vision réduite à l'utilisation d'une ou plusieurs caméras dans la région d'intérêt. Durant ma thèse, j'ai conçu et mis en oeuvre des nouvelles méthodes informatiques de traitement 3D d'images radiologiques ainsi que de nouvelles utilisations médicales de ces images. Les contributions présentées concernent la visualisation et le traitement des données, la segmentation de structures 3D, la fusion mono et multimodale et l'aide à la réalisation d'interventions. Les applications présentées concernent notamment la planification et la réalisation d'interventions sous coelioscopie et de ponctions mais aussi l'imagerie industrielle. L'utilisation conjointe de différentes modalités d'images permet d'améliorer la visualisation, la manipulation et la compréhension de scènes tridimensionnelles, conduisant à une plus grande compréhension des observations et à une meilleure prise de décision.

Dans un contexte d'exploration et d'exploitation pétrolières, le traitement des données acquises par sismique réflexion requiert une analyse structurale à des fins de modélisation. Cette analyse passe par une phase d'extraction des structures horizontales représentant les empilements géologiques. Les techniques actuelles nécessitent beaucoup de temps et l'attention quasi permanente d'un spécialiste pour réaliser et valider cette opération effectuée structure par structure. De plus, la quantité de données sismiques augmentant rapidement avec l'évolution des techniques d'acquisition, leur traitement représente une charge de travail de plus en plus importante. Dans cette thèse, nous nous proposons d'alléger la phase d'extraction des structures horizontales en réalisant une segmentation presque automatique de ces dernières à l'aide d'outils basés sur des techniques morphologiques et topologiques. Nous présentons également quelques applications s'appuyant sur les structures que nous avons extraites. Ces applications facilitent l'analyse des données 3D en proposant de nouvelles méthodes de calcul d'attributs sismiques à partir des données d'amplitude.

abstract: The Dual Marching Tetrahedra algorithm is a generalization of the Dual Marching Cubes algorithm, used to build a boundary surface around points which have been assigned a particular scalar density value, such as the data produced by and Magnetic Resonance Imaging or Computed Tomography scanner. This boundary acts as a skin between points which are determined to be "inside" and "outside" of an object. However, the DMT is vague in regards to exactly where each vertex of the boundary should be placed, which will not necessarily produce smooth results. Mesh smoothing algorithms which ignore the DMT data structures may distort the output mesh so that it could incorrectly include or exclude density points. Thus, an algorithm is presented here which is designed to smooth the output mesh, while obeying the underlying data structures of the DMT algorithm. / Dissertation/Thesis / M.S. Computer Science 2011

Cerveja é uma bebida alcoólica mundialmente popular e a mais consumida no Brasil. Existem diversos estilos de cerveja no mundo, os quais são produzidos por modificações no processo de produção, no uso de diferentes ingredientes, na maturação utilizando barris de madeira e/ou adição de fragmentos de madeira, entre outros. A maturação em madeira pode proporcionar complexidade aromática às bebidas, sendo a madeira de carvalho amplamente utilizada para a maturação de bebidas alcoólicas. O uso dessa madeira na maturação da cerveja é o foco desse trabalho, que maturou cervejas a 0°C, durante três meses, em garrafas de vidro de 600 mL, barris de carvalho e recipientes plásticos com cubos de carvalho, na dose de 3g/L, provenientes de três níveis diferentes de tosta (leve, média, e alta). Das cervejas oriundas dos diferentes tratamentos, foram analisadas graduação alcoólica, pH, acidez total, turbidez, fenólicos totais, cor e amargor; os compostos voláteis (aldeídos, ésteres e álcoois superiores) foram analisados por Cromatografia gasosa (FID) e os compostos fenólicos de baixo peso molecular (ácido gálico, 5-hidroximetil-furfural, furfural, ácido vanílico, ácido siríngico, vanilina, siringaldeído, coniferaldeído e sinapaldeído) por Cromatografia líquida de alta eficiência (HPLC). As cervejas também foram analisadas sensorialmente mediante teste de preferência. A análise dos resultados mostrou que não houve alterações na qualidade da cerveja que pudessem ser atribuídas ao armazenamento com madeira. Os compostos voláteis tiveram pequenas alterações, por outro lado, os compostos fenólicos de baixo peso molecular foram os que apresentaram maiores incrementos no período de três meses de maturação. Não houve diferença na aceitação sensorial entre as cervejas maturadas com cubos de madeira, barril e em garrafas de vidro. Futuros estudos são necessários para que seja possível obter um produto de qualidade que possa satisfazer o consumidor e seja acessível à indústria. / Beer is a very popular alcoholic beverage in the world and the most widely consumed in Brazil. There are many styles of beer in the world that can be produced by changes in the production process, use of various ingredients, maturation using wood barrels and / or addition of wood fragments, and others. Wood maturation can provide aromatic complexity to alcoholic beverages, and the oak wood is widely used. The use of oak in the maturation of beer is the focus of this work. The beers matured at 0 °C for three months in glass bottles of 600 mL, oak barrels and plastic containers with oak cubes at a dose of 3g/L, with three different levels of toasting (light, medium, and high). Beers resulting from the different treatments were analyzed physico-chemically (alcohol content, pH, total acidity, turbidity, total phenolics, color and bitterness), the volatile compounds (aldehydes, esters and higher alcohols) by gas chromatography (FID), the low molecular weight phenolic compounds (gallic acid, 5-hydroxymethylfurfural, furfural, vanillic acid, syringic acid, vanillin, syringaldehyde, coniferaldehyde and sinapaldehyde) by High Performance Liquid Chromatography (HPLC), and sensory. The analysis shows that there were no qualities changes in beer that could be attributed to the storage in contact with oak wood. The volatile compounds had minor changes; the low molecular weight phenolic compounds were those with the greatest increases within three months of maturation. There was no difference in sensory acceptance between beers matured in oak barrel, oak cubes and glass bottles. This work suggests that wood influences sensory beer, but more studies are needed to be able to get a quality product that can satisfy the consumer and is accessible to the industry.

The International Space Station provides a high-quality of microgravity and extended exposure time which makes it a platform of choice for microgravity research. In order to increase accessibility of onboard experimentation, Space Applications Services will soon launch the ICE Cubes facility as part of its ICE Cubes Service. The facility is foreseen to host standardized plug-and-play payload cubes to reduce overall cost and procedure time required to install payloads on the station. To remotely support the facility it is decided to develop a utility cube named Cube-Zero that will be launched and installed with the facility on the station. This thesis work included the complete design, development and documentation of the cube. The thesis started by conducting a preliminary needs and market study from which two specific purposes were defined for the cube. In addition to its original function of support-utility, the cube is tasked to be a technical commercial demonstrator for the service. This led to the conceptual design of the cube as a multidisciplinary framework able to host two user-defined experiment modules. The preliminary concept was further refined in this paper and with support of prototypes, simulations and analyses led to a final functional design for the Cube-Zero. The work is concluded with the manufacturing of an engineering model of the cube. The model is fully operational, can support the test of the facility before launch and can demonstrate to users its versatility and ease of use in operating any kind of experiment module. Eventually, the information gathered in this thesis report will support future users into developing their own Cube-Zero payload module and guide Space Applications Services into manufacturing, testing and operating the Cube-Zero protoflight model. / ICE Cubes