A triangulação de Delaunay de um conjunto de pontos é uma importante entidade geométrica cujas aplicações abrangem diversas áreas da ciência. Triangulações regulares, que podem ser vistas como uma generalização da triangulação de Delaunay, onde pesos são associados aos vértices, também têm sido aplicadas em diversos problemas como reconstrução a partir de nuvens de pontos [5], geração de malha [12], modelagem molecular [7] e muitos outros. Apesar de ser muito utilizada, a fundamentação teórica referente à triangulação regular ainda não está tão desenvolvida quanto para triangulação de Delaunay. Por exemplo, pouco se sabe a respeito da dinâmica de uma triangulação regular [22] quando os pesos associados aos vértices mudam. Este trabalho tem como objetivo principal desenvolver um arcabouço teórico e computacional que permita representar uma triangulação qualquer como uma triangulação regular. Para isso, um estudo da dinâmica das operações de flip frente à variação de pesos nos vértices deve ser realizado. Este estudo tem como base o mapeamento da triangulação em um politopo que define os possíveis pesos para os vértices. Tal politopo pode ser obtido por meio de um sistema de inequações que gera um problema de programação linear cuja solução fornece os pesos adequados. A transformação de uma triangulação qualquer em triangulação regular permite o desenvolvimento de novas técnicas de morphing entre malhas e algoritmos para modelar níveis de detalhe, sendo este mais um objetivo deste trabalho / Delaunay triangulation of a set of points is an important geometrical entity whose applications encompass a range of scientfic fields. Regular triangulations, which can be seen as a generalization of Delaunay triangulation where weights are assigned to vertices, have also been widely employed in several problems, as for example mesh reconstruction from point clouds [5], mesh generation [12] and molecular modelling [7]. In spite of their applicability, the theoretical background of regular triangulations is not so developed as the theory of Delaunay triangulation. For example, the dynamic of regular triangulation is not completely known when the vertices weights change [22]. This work aims at developing a computational and theoretical framework that allow to represent a given triangulation as a regular triangulation. In this context, an investigation into the dynamic of edge ip operations regarding changes in the vertices weight must be accomplished. This investigation is based on mapping the triangulation in a polytope that defines the space of vertices weights. Such polytope can be built from an inequation system that can be associate to a linear program problem whose solution supplies the appropriated weights. By representing a triangulation as a regular triangulation one can conceive a new mesh morphing scheme and level of detail algorithm, being this another goal of this work

Les modèles géologiques numériques 2D et 3D permettent de comprendre l'organisation spatiale des roches du sous-sol. Ils sont également conçus pour réaliser des simulations numériques afin d’étudier ou de prédire le comportement physique du sous-sol. Pour résoudre les équations qui gouvernent les phénomènes physiques, les structures internes des modèles géologiques peuvent être discrétisées spatialement à l’aide de maillages. Cependant, la qualité des maillages peut être considérablement altérée à cause de l’inadéquation entre, d’une part, la géométrie et la connectivité des objets géologiques à représenter et, d’autre part, les contraintes requises sur le nombre, la forme et la taille des éléments des maillages. Dans ce cas, il est souhaitable de modifier un modèle géologique afin de pouvoir générer des maillages de bonne qualité permettant la réalisation de simulations physiques fidèles en un temps raisonnable. Dans cette thèse, j’ai développé des stratégies de réparation et de simplification de modèles géologiques 2D dans le but de faciliter la génération de maillages et la simulation de processus physiques sur ces modèles. Je propose des outils permettant de détecter les éléments des modèles qui ne respectent pas le niveau de détail et les prérequis de validité spécifiés. Je présente une méthode pour réparer et simplifier des coupes géologiques de manière locale, limitant ainsi l’extension des modifications. Cette méthode fait appel à des opérations d’édition de la géométrie et de la connectivité des entités constitutives des modèles géologiques. Deux stratégies sont ainsi explorées : modifications géométriques (élargissements locaux de l'épaisseur des couches) et modifications topologiques (suppressions de petites composantes et fusions locales de couches fines). Ces opérations d’édition produisent un modèle sur lequel il est possible de générer un maillage et de réaliser des simulations numériques plus rapidement. Cependant, la simplification des modèles géologiques conduit inévitablement à la modification des résultats des simulations numériques. Afin de comparer les avantages et les inconvénients des simplifications de modèles sur la réalisation de simulations physiques, je présente trois exemples d'application de cette méthode : (1) la simulation de la propagation d'ondes sismiques sur une coupe au sein du bassin houiller lorrain, (2) l’évaluation des effets de site liés à l'amplification des ondes sismiques dans le bassin de la basse vallée du Var, et (3) la simulation d'écoulements fluides dans un milieu poreux fracturé. Je montre ainsi (1) qu'il est possible d’utiliser les paramètres physiques des simulations, la résolution sismique par exemple, pour contraindre la magnitude des simplifications et limiter leur impact sur les simulations numériques, (2) que ma méthode de simplification de modèles permet de réduire drastiquement le temps de calcul de simulations numériques (jusqu’à un facteur 55 sur une coupe 2D dans le cas de l’étude des effets de site) tout en conservant des réponses physiques équivalentes, et (3) que les résultats de simulations numériques peuvent être modifiés en fonction de la stratégie de simplification employée (en particulier, la modification de la connectivité d’un réseau de fractures peut modifier les écoulements fluides et ainsi surestimer ou sous-estimer la quantité des ressources produites). / Numerical geological models help to understand the spatial organization of the subsurface. They are also designed to perform numerical simulations to study or predict the rocks physical behavior. The internal structures of geological models are commonly discretized using meshes to solve the physical governing equations. The quality of the meshes can be, however, considerably degraded due to the mismatch between, on the one hand, the geometry and the connectivity of the geological objects to be discretized and, on the other hand, the constraints imposed on number, shape and size of the mesh elements. As a consequence, it may be desirable to modify a geological model in order to generate good quality meshes that allow realization of reliable physical simulations in a reasonable amount of time. In this thesis, I developed strategies for repairing and simplifying 2D geological models, with the goal of easing mesh generation and simulation of physical processes on these models. I propose tools to detect model elements that do not meet the specified validity and level of detail requirements. I present a method to repair and simplify geological cross-sections locally, thus limiting the extension of modifications. This method uses operations to edit both the geometry and the connectivity of the geological model features. Two strategies are thus explored: geometric modifications (local enlargements of the layer thickness) and topological modifications (deletions of small components and local fusions of thin layers). These editing operations produce a model on which it is possible to generate a mesh and to realize numerical simulations more efficiently. But the simplifications of geological models inevitably lead to the modification of the numerical simulation results. To compare the advantages and disadvantages of model simplifications on the physical simulations, I present three applications of the method: (1) the simulation of seismic wave propagation on a cross-section within the Lorraine coal basin, (2) the site effects evaluation related to the seismic wave amplifications in the basin of the lower Var river valley, and (3) the simulation of fluid flows in a fractured porous medium. I show that (1) it is possible to use the physical simulation parameters, like the seismic resolution, to constrain the magnitude of the simplifications and to limit their impact on the numerical simulations, (2) my method of model simplification is able to drastically reduce the computation time of numerical simulations (up to a factor of 55 in the site effects case study) while preserving an equivalent physical response, and (3) the results of numerical simulations can be changed depending on the simplification strategy employed (in particular, changing the connectivity of a fracture network can lead to a modification of fluid flow paths and overestimation or underestimation of the quantity of produced resources).

<p>The problem of estimating an adequate level of detail for an object for a specific view is one of the important problems in computer 3d-graphics and is especially important in real-time applications. The well-known continuous level-of-detail technique, Real-time Optimally Adapting Meshes (ROAM), has been employed with success for almost 10 years but has at present, due to rapid development of graphics hardware, been found to be inadequate. Compared to many other level-of-detail techniques it cannot benefit from the higher triangle throughput available on graphics cards of today.</p><p>This thesis will describe the implementation of the new version of ROAM (informally known as ROAM 2.0) for the purpose of massive planetary data visualization. It will show how the problems of the old technique can be bridged to be able to adapt to newer graphics card while still benefiting from the advantages of ROAM. The resulting implementation that is presented here is specialized on spherical objects and handles both texture and geometry data of arbitrary large sizes in an efficient way.</p>

Den här rapporten innehåller ett projekt, framtagningen av en stavhållare till en skidlift av typen sittlift. Projektet har utförts på Växjö universitet med stöd från handledare och i samarbete med företaget Ackurat Industriplast AB. Projektet omfattar tio veckors arbete och är på C-uppsatsnivå utfört av två studenter med högskoleingenjörsutbildning med inriktning produktutveckling &amp; industriell design. Då ingen produkt av det här slaget existerar innefattar projektet alla steg i produktutvecklingen från förstadiet till färdig produkt. Stavhållaren är tänkt att formsprutas i plast. Stavhållaren skall placeras på liftsolens skyddsarm där det i nuläget finns reklamskyltar. Tanken är att stavhållaren skall integreras med reklamskylten. Produkten skall klara av den tuffa miljö den kommer att utsättas för, vilket ställer krav på material och konstruktion. Även det estetiska uttrycket är av vikt och produkten är tänkt att tala om vad den ska användas till. Syftet med projektet är att förbättra en produkt som exponerar reklam och integrera en funktion vilken kommer underlätta för alpinsportare. Metoden som använts genomgående i projektet är tillämpad kunskap om produktutveckling som erhållits under utbildningen. Metoden har använts för att inte missa någon viktig del i processen. / This report includes a project, development of a pole holder for a ski pole of the type chair lift. The project has been executed on Växjö University with help from a supervisor and in cooperation with the company Ackurat Industriplast AB. The project encloses ten weeks of work and is on C-level executed by two students with bachelor in mechanical engineering with directionally in product development and industrial design. Because no product with this design exists this project involves all steps in the product development from early stage to a complete product. The pole holder is supposed to be manufactured in plastic by injection-moulding. The ski pole is to be placed on the safe shackle on the chair lift where it in the present situation prevail advertising signs. The thought is to integrate the ski pole with the advertising sign. The product shall withstand the rough environment it will be exposed to, which set demands on material and construction. Also the esthetic impression is really important which is suppose to attract and the product is supposed to show what it is meant for. The purpose with this project is to improve a product that expose publicity and integrate a function which will make it easier for alpine downhillers. The method that has been used trough going in this project is applied knowledge about product development that has been gained during the education. The method has been used in order to minimize the risk to miss important steps in the process.

Breast cancer is a major health concern in the United States. Mammography is the gold standard for screening breast cancer and screen-film technology is still widely used in the screening for breast cancer. However, screen-film systems have limited dynamic range and contrasts compared to digital systems, and do not offer integrated image processing capabilities. Recently, digital mammography has seen an upsurge in clinical adoption but current digital mammography systems are limited in terms of their spatial resolution. Therefore, high-resolution digital mammography systems with superior signal-to-noise ratio and contrast characteristics need to be explored. A monolithic, single module high-resolution (39 um) digital x-ray platform (Fairchild Imaging Inc., Milpitas, CA) was developed and characterized for digital mammography. The architecture was extended to a large area (16 x 24-cm) multi-module solid-state imager with variable resolution (39 and 78-um). In addition, a four module (16 x 16-cm) imaging architecture with 78-um pixel was explored for high-resolution contrast enhanced digital mammography for the detection of malignancy-associated angiogenesis. Simulations based on the cascaded linear systems framework were performed in order to characterize the physical properties of the imaging platforms such as the modulation transfer function (MTF), noise power spectra (NPS), and detective quantum efficiency (DQE). Experimental measurements of imager performance was also conducted and compared to model predicted results. Further, perceptual analysis of the prototype imaging platform for digital mammography was performed. Various imaging platforms were successfully developed and investigated to identify essential parameters for high-resolution digital x-ray breast imaging. The single module prototype exhibited physical characteristics that are favorable for digital mammography. Good agreement between model and experimental results were observed demonstrating the utility of such models for further system improvement. The large area 16 x 24-cm prototype demonstrated superior contrast-detail characteristics compared to a clinical FFDM system (100 um pixel) at both 39 and 78-um pixel sizes. Both experimental and theoretical results pointed towards the feasibility of contrast enhanced mammography at mean x-ray glandular dose levels substantially lower than mammography under the conditions investigated. Qualitative analysis of contrast enhanced digital mammography indicated favorable image quality.

The difficulty in developing bolted connection designs lies in the limitations in existing methods to characterize their strength and typically nonlinear response due to the complex interaction of the bolts and structural components. Yet it is necessary for the engineer to be able to determine the three main connection response characteristics: stiffness, strength, and ductility to account for their influence on the overall structural response behavior. The need for better connection response characterization becomes even more crucial in a performance based design approach or when designing partially-restrained moment frames. Several welded moment resisting frame connections were found to have serious failures following the 1994 Northridge earthquake leading to more interest and research on bolted connections as an alternative. In this study a refined three dimensional nonlinear finite element modeling approach to accurately simulate the response of bolted connections is presented. Sensitivity studies of modeling parameters are also performed. A nonlinear response dataset of over 400 connection cases is generated using this approach with a parametric bolted angle connection model. The use of a parametric Richard-Abbott type function and a neural network, calibrated using the response dataset, as practical tool to model the nonlinear stiffness response of bolted connections under monotonic loading is demonstrated and assessed. Failure criteria that can be practically used in conjunction with the refined three dimensional finite element models without any additional modeling requirements are developed. The stress modified critical strain (SMCS) criterion based on the void growth and coalescence mechanism initiating ductile fracture in steel is used for determining failure in the connection member. The bolt failure criterion developed is a mechanics based model using the elliptical interaction of the tensile and shear capacity envelope. The failure criteria and bolted angle response dataset is combined to assess in detail the impact of geometry and topography of the bolted angle connections on the following response characteristics: strength, initial stiffness, plastic stiffness, and absolute ductility or the displacement capacity. Finally, using the dataset of bolted angle connection response, along with their capacities and failure modes determined using the developed failure criteria, the prying strength models in the AISC LRFD Specifications, Eurocode, and a hybrid model are assessed and found to be very conservative for some cases. Based on these results a modified Eurocode and hybrid prying strength model is proposed which greatly improves the prying strength prediction. These prying models are assessed and verified using experimental data found in literature.

<p>Den här rapporten innehåller ett projekt, framtagningen av en stavhållare till en skidlift av typen sittlift. Projektet har utförts på Växjö universitet med stöd från handledare och i samarbete med företaget Ackurat Industriplast AB. Projektet omfattar tio veckors arbete och är på C-uppsatsnivå utfört av två studenter med högskoleingenjörsutbildning med inriktning produktutveckling & industriell design.</p><p>Då ingen produkt av det här slaget existerar innefattar projektet alla steg i produktutvecklingen från förstadiet till färdig produkt. Stavhållaren är tänkt att formsprutas i plast. Stavhållaren skall placeras på liftsolens skyddsarm där det i nuläget finns reklamskyltar. Tanken är att stavhållaren skall integreras med reklamskylten. Produkten skall klara av den tuffa miljö den kommer att utsättas för, vilket ställer krav på material och konstruktion. Även det estetiska uttrycket är av vikt och produkten är tänkt att tala om vad den ska användas till.</p><p>Syftet med projektet är att förbättra en produkt som exponerar reklam och integrera en funktion vilken kommer underlätta för alpinsportare. Metoden som använts genomgående i projektet är tillämpad kunskap om produktutveckling som erhållits under utbildningen. Metoden har använts för att inte missa någon viktig del i processen.</p> / <p>This report includes a project, development of a pole holder for a ski pole of the type chair lift. The project has been executed on Växjö University with help from a supervisor and in cooperation with the company Ackurat Industriplast AB. The project encloses ten weeks of work and is on C-level executed by two students with bachelor in mechanical engineering with directionally in product development and industrial design.</p><p>Because no product with this design exists this project involves all steps in the product development from early stage to a complete product. The pole holder is supposed to be manufactured in plastic by injection-moulding. The ski pole is to be placed on the safe shackle on the chair lift where it in the present situation prevail advertising signs. The thought is to integrate the ski pole with the advertising sign. The product shall withstand the rough environment it will be exposed to, which set demands on material and construction. Also the esthetic impression is really important which is suppose to attract and the product is supposed to show what it is meant for.</p><p>The purpose with this project is to improve a product that expose publicity and integrate a function which will make it easier for alpine downhillers. The method that has been used trough going in this project is applied knowledge about product development that has been gained during the education. The method has been used in order to minimize the risk to miss important steps in the process.</p>

Direct Volume Rendering (DVR) is a visualization technique that has proved to be a very powerful tool in many scientific visualization applications. Diagnostic medical imaging is one domain where DVR could provide clear benefits in terms of unprecedented possibilities for analysis of complex cases and highly efficient work flow for certain routine examinations. The full potential of DVR in the clinical environment has not been reached, however, primarily due to limitations in conventional DVR methods and tools. This thesis presents methods addressing four major challenges for DVR in clinical use. The foundation of all methods is to incorporate the domain knowledge of the medical professional in the technical solutions. The first challenge is the very large data sets routinely produced in medical imaging today. To this end a multiresolution DVR pipeline is proposed, which dynamically prioritizes data according to the actual impact in the rendered image to be reviewed. Using this prioritization the system can reduce the data requirements throughout the pipeline and provide high performance and visual quality in any environment. Another problem addressed is how to achieve simple yet powerful interactive tissue classification in DVR. The methods presented define additional attributes that effectively captures readily available medical knowledge. The task of tissue detection is also important to solve in order to improve efficiency and consistency of diagnostic image review. Histogram-based techniques that exploit spatial relations in the data to achieve accurate and robust tissue detection are presented in this thesis. The final challenge is uncertainty visualization, which is very pertinent in clinical work for patient safety reasons. An animation method has been developed that automatically conveys feasible alternative renderings. The basis of this method is a probabilistic interpretation of the visualization parameters. Several clinically relevant evaluations of the developed techniques have been performed demonstrating their usefulness. Although there is a clear focus on DVR and medical imaging, most of the methods provide similar benefits also for other visualization techniques and application domains.

Nuosavybės teisių į miesto žemę atkūrimo darbai teisiškai buvo sureglamentuoti tik 2002 m. patikslinus įstatymą. Nuo to laiko piliečiams ne tik suteikiami nuosavybėn žemės sklypai prie pastatų ar nauji žemės sklypai individualiai statybai, bet ir grąžinama natūra laisva (neužstatyta) miesto žemė. Bendras žemės plotas, į kurį prašoma atkurti nuosavybės teises Panevėžio mieste – 2482 ha. Iki 2009 m. pradžios Panevėžio mieste atkurtos nuosavybės teisės į 43,6 proc. pretendentų prašymuose nurodyto ploto. Grąžinta natūra 134 ha žemės. 2009 m. pradžioje dar nebuvo suteikta nuosavybėn žemės sklypai 703 asmenims. Esant tokiems žemės reformos tempams, visus žemės reformos darbus Panevėžio mieste bus galima užbaigti tik per 11 metų. Siekiant šį procesą paspartinti, siūloma: miesto savivaldybei rengti daugiau detaliųjų planų, kuriuose suformuojami kompensavimui skirti žemės sklypai; sudaryti sąlygas už miesto žemę gauti žemės sklypus kaimo vietovėje, – ne tik žemės ūkio paskirties žemėje, bet ir miškų ūkio paskirties žemėje. / Reestablishment of urban real property rights legally were regulated in 2002, when legal act was corrected. From that time, the citizens are not only granted for ownership of land parcels near buildings or new land parcels for individual construction, but restored free natural urban land. General land plot, for which is applied to reestablish property rights in Panevezys city is 2482 ha. Till the beginning of 2009, reestablished property rights to the 43.6 percent from all applied land plot. Restored 134 ha of free natural land. In the beginning of 2009 the property rights were not reestablished to 703 citizens. According to the situation all the land reform in Panevezys will finish after 11 years. The way to solve this problem faster, we suggest municipality, to do more detail plans of creation land parcels for compensation, to create conditions for citizens to get a rural land and forest land in accordance of urban land.

Darbą atliko VPU Socialinių mokslų fakulteto Sociologijos ir politologijos katedros Politinės sociologijos magistrantūros neakivaizdinio sk. studentas Andrius Bakštonas. Tyrimo tikslas – ištirti etninės kultūros vaidmenį plėtojant kaimo turizmą. Darbe buvo iškeltos šios hipotezės: 1. Lietuvos turizmo struktūra, respondentų manymu, tinkama etninės kultūros išsaugojimui, o kaimo turizmas yra vertinamas kaip vienas iš pagrindinių būdų, padedančių išsaugoti etninę kultūrą. 2. Pagrindiniai etninės kultūros elementai, skatinantys pasirinkti kaimo turizmą, yra gamta (miškas, vandens telkinys), nutolusi civilizacija. 3. Trys socialinės respondentų grupės (kaimo sodybų savininkai, poilsiautojai ir kaimo bendruomenės gyventojai) skirtingai vertina etninės kultūros elementų (architektūrinis paveldas, maisto paveldas, kultūrinis paveldas) pritaikomumą plėtojant kaimo turizmą. Kiekybinio tyrimo metu apklausta 110 respondentų, tyrimas atliktas Vilniaus regione. Tyrimo analizė atlikta atsižvelgiant į bendrus respondentų atsakymus bei į atsakymus pagal respondentų grupes (respondentai suskirstyti atsižvelgiant į jų socialinę padėtį į tris grupes: kaimo turizmo sodybų savininkus, turistus bei kaimo bendruomenės narius). Atlikus tyrimo duomenų analizę paaiškėjo, kad hipotezės: 1. Lietuvos turizmo struktūra, respondentų manymu, tinkama etninės kultūros išsaugojimui, o kaimo turizmas yra vertinamas kaip vienas iš pagrindinių būdų, padedančių išsaugoti etninę kultūrą, pasitvirtina; 2... [toliau žr. visą tekstą] / The work was made by Andrius Bakštonas, Political sociology master‘s degree extramural student of VPU Social sciences faculty Sociology and political sciences department. The purpose of investigation was to research the role of ethnical culture to the development of country tourism. These hypotheses were hypothesized in the work: 1. According to respondents’ opinion, the structure of Lithuania‘s tourism is suitable for upholding of the ethnical culture and the country tourism is appreciable as one of the basic ways that helps to uphold the ethnical culture. 2. The main elements of ethnical culture, that motivates to choose the country tourism are nature (the forest, the water body), the distant civilization. 3. Three social groups of respondents’ (the owners of the country granges, holidaymakers and country folks) appreciate the adaptability of ethnical culture elements (architectural heritage, nutrition heritage, cultural heritage) in developing of country tourism differently. There were 110 respondents questioned during the investigation that was performed in region of Vilnius. The analysis of the investigation was made depending on common respondents’ answers and on answers of different respondents’ groups (respondents were marshaled depending on their social status to three groups: the owners of the country granges, holidaymakers and country folks). There was made the analysis of the results of investigation information and it emerged that hypotheses: 1. According to... [to full text]