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L’émergence d’interrupteurs de puissance en SiC permet d’envisager des convertisseurs de puissance capables de fonctionner au sein des environnements sévères tels que la haute tension (> 10 kV ) et la haute température (> 300 °C). Aucune solution de commande spécifique à ces environnements n’existe pour le moment. Le développement de fonctions élémentaires en SiC (comparateur, oscillateur) est une étape préliminaire à la réalisation d’un premier démonstrateur. Plusieurs laboratoires ont développé des fonctions basées sur des transistors bipolaires, MOSFETs ou JFETs. Cependant les recherches ont principalement portées sur la conception de fonctions logiques et non sur l’intégration de drivers de puissance. Le laboratoire AMPERE (INSA de Lyon) et le Centre National de Microélectronique de Barcelone (Espagne) ont conçu un MESFET latéral double grille en SiC. Ce composant élémentaire sera à la base des différentes fonctions intégrées envisagées. L’objectif de ces recherches est la réalisation d’un convertisseur élévateur de tension "boost" monolithique et de sa commande en SiC. La démarche scientifique a consisté à définir dans un premier temps un modèle de simulation SPICE du MESFET SiC à partir de caractérisations électriques statique et dynamique. En se basant sur ce modèle, des circuits analogiques tels que des amplificateurs, oscillateurs, paires différentielles, trigger de Schmitt ont été conçus pour élaborer le circuit de commande (driver). La conception de ces fonctions s’avère complexe puisqu’il n’existe pas de MESFETs de type P et une polarisation négative de -15 V est nécessaire au blocage des MESFETs SiC. Une structure constituée d’un pont redresseur, d’un boost régulé avec sa commande basée sur ces différentes fonctions a été réalisée et simulée sous SPICE. L’ensemble de cette structure a été fabriqué au CNM de Barcelone sur un même substrat SiC semi-isolant. L’intégration des éléments passifs n’a pas été envisagée de façon monolithique (mais pourrait être considérée pour les inductances et capacités dans la mesure où les valeurs des composants intégrés sont compatibles avec les processus de réalisation). Le convertisseur a été dimensionné pour délivrer une de puissance de 2.2 W pour une surface de 0.27 cm2, soit 8.14 W/cm2. Les caractérisations électriques des différents composants latéraux (résistances, diodes, transistors) valident la conception, le dimensionnement et le procédé de fabrication de ces structures élémentaires, mais aussi de la majorité des fonctions analogiques. Les résultats obtenus permettent d’envisager la réalisation d’un driver monolithique de composants Grand Gap. La perspective des travaux porte désormais sur la réalisation complète du démonstrateur et sur l’étude de son comportement en environnement sévère notamment en haute température (> 300 °C). Des analyses des mécanismes de dégradation et de fiabilité des convertisseurs intégrés devront alors être envisagées. / The new SiC power switches is able to consider power converters, which could operate in harsh environments as in High Voltage (> 10kV) and High Temperature (> 300 °C). Currently, they are no specific solutions for controlling these devices in harsh environments. The development of elementary functions in SiC is a preliminary step toward the realization of a first demonstrator for these fields of applications. AMPERE laboratory (France) and the National Center of Microelectronic of Barcelona (Spain) have elaborated an elementary electrical compound, which is a lateral dual gate MESFET in Silicon Carbide (SiC). The purpose of this research is to conceive a monolithic power converter and its driver in SiC. The scientific approach has consisted of defining in a first time a SPICE model of the elementary MESFET from electric characterizations (fitting). Analog functions as : comparator, ring oscillator, Schmitt’s trigger . . . have been designed thanks to this SPICE’s model. A device based on a bridge rectifier, a regulated "boost" and its driver has been established and simulated with the SPICE Simulator. The converter has been sized for supplying 2.2 W for an area of 0.27 cm2. This device has been fabricated at CNM of Barcelona on semi-insulating SiC substrate. The electrical characterizations of the lateral compounds (resistors, diodes, MESFETs) checked the design, the "sizing" and the manufacturing process of these elementary devices and analog functions. The experimental results is able to considerer a monolithic driver in Wide Band Gap. The prospects of this research is now to realize a fully integrated power converter in SiC and study its behavior in harsh environments (especially in high temperature > 300 °C). Analysis of degradation mechanisms and reliability of the power converters would be so considerer in the future.

The presented work investigates the mechanisms of propagation of heat and moisture in the structure of heat-insulating materials based on natural fibers. The main aim of this work is the experimental verification of theoretical patterns, which are involved in the transport of heat and moisture in fibrous materials, especially the influence of fibers thickness and density of the fibrous materials. To widen outputs of the work were selected different kinds of natural fiber materials of vegetable and animal origin. The results of the work should help to optimize the production processes of natural insulation materials considering their optimal thermal properties. From the data collected are deduced general conclusions to better understanding the behavior of these materials.

The subject of my diploma thesis is a new-building of a municipal authority with a nursery school in Obora near Boskovice. The objects are statically and operationally separated from each other, but they formo ne unit. The building is located on the corner of the village in a flat terrain and thus forms the dominant feature of the village and a landmark. The target of the design was to create a building that will harmoniously connect to the surrounding buildings, public spaces and the school garden. The municipal authority has a rectangular floor plan, two-storey, basement, covered with a sloping roof, the building has a designed elevator. In the basement there are cellars of local associations, on the ground floor there is information center, a municipal library and on the first floor there is a municipal office with a registry office and a ceremonial hall. The attic can be used in the future for municipal apartments for rent. An official board with a public space is designed ahead of the municipal office. A photovoltaic power plant will be located on the roof of the municipal office. The nursery school has a trapezoidal floor plan, ground floor, no basement, covered with a vegetated flat roof. In the nursery school there is a children's day room with a storage room, storage of mattresses, teaching aids, food preparation, technical and hygienic facilities. The structural systém of both objects is longitudinal, wall. The underground part of the municipal office is designed in a white concrete tub system. The vertical load-bearing constructions are made from cut ceramic blocks. The horizontal constructions in the municipal office are monolithic, ferroconcrete, and in the nursery school they are prefabricated, ferroconcrete. The project was made in AutoCad software application, 3D model in 3D modelling computer program SketchUp.

Master’s thesis deals with complete project documentation of newly built object of library and mediatheque located on the site in České Budějovice. It is a three-storey building divided into three parts, one-storey, two-storey and three-storey. It is partly basement. The underground part is devoted to main storage spaces of library services, management offices and social facilities for staff (toilets, changing rooms, washrooms). This part of the building has own entrance for employees. In the 1st floor is located the main library area along with exhibition spaces and the main entrance for visitors with self service cloakroom. In the 2nd floor are designed library spaces for visually impaired persons with fund of audio books, CDs and DVDs, a lecture hall with a projector and own kitchen and space for reading magazines and periodicals. From this floor is possible access to the outdoor terrace, which has own terrace furniture store nearby. In the 3rd floor is located a literary café with its own facilities. In each floor are also designed sanitary facilities for use by persons with limited ability of movement and orientation. All floors are connected by stairs and passenger lifts. In terms of construction, the building is designed as a frame, in the underground parts made of reinforced concrete, the overhead of glued laminated timber elements. The ceiling structure designed over the underground floor is monolithic reinforced concrete slab. The ceilings in the upper part are designed as a wooden beamed made of the glued laminated timber elements. The building has a pent roof created by wooden trusses assembled with punched metal plate fasteners. The foundations are designed as belts and footings. The study, detailed documentation, thermal-technical evaluation of selected structures and fire safety of the building are processed. For processing of the thesis were used software AutoCAD 2010, Teplo 2011, Area 2011, Ztráty 2011 and Fire NX 802 PRO.