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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
651

L'impact du changement technique endogène sur les politiques climatiques

Sassi, Olivier 21 November 2008 (has links) (PDF)
Cette thèse porte sur la modélisation économique des politiques de réduction des émissions de gaz à effet de serre. Nous explorons, avec un modèle hybride, les conséquences du passage d'une économie du changement climatique sous tendue par une vision exogène du progrès technique à un cadre où il est induit par l'ensemble des signaux économiques. Les résultats soulignent les risques de bifurcation vers des trajectoires de référence très intensives en carbone. Les scénarios avec politiques climatiques démontrent l'existence d'un écart entre l'optimisme qui était attaché à l'induction du progrès technique par les politiques climatiques et les résultats que nous obtenons. Cette thèse propose enfin de concevoir les politiques climatiques plus comme une articulation de mesures spécifiques que comme le déploiement d'un unique signal prix. Nous démontrons qu'une mise en cohérence des politiques d'infrastructures de transport avec l'objectif climatique permet de réduire fortement son coût
652

Application d'un code de CFD atmosphérique à l'estimation du productible éolien en terrain complexe

Laporte, Laurent 12 December 2008 (has links) (PDF)
La thèse se décompose en deux parties. La première concerne l'utilisation du code de CFD atmosphérique Mercure Saturne pour estimer le potentiel éolien en terrain complexe. Une campagne de mesure a été menée par EDF pour disposer de données d'entrée et de validation. Une méthodologie a été développée utilisant des profils méso-échelle comme conditions limites du code CFD. Elle utilise la classification automatique pour réduire le nombre de simulations nécessaires au calcul du potentiel. La validation du code sur le cas connu de la colline d'Askervein, la méthodologie et les comparaisons avec les mesures sur le site complexe choisi sont présentées et discutées. La seconde partie concerne l'étude des sillages avec le code Mercure Saturne. Une méthode de représentation des efforts, exercés par les pales sur le vent, utilisant des termes sources a été implémentée. Ces derniers sont calculés par la méthode BEM. Deux comparaisons en soufflerie sont proposées pour la validation
653

Vertical Seismic Profiling in the Krafla Geothermal Field, NE-Iceland / Seismische Vertikalprofilierung im Krafla Geothermiefeld, NO-Island

Kästner, Felix 03 January 2017 (has links) (PDF)
A VSP test experiment at the high temperature geothermal field Krafla in NE-Iceland has been carried out. In two boreholes a zero-, far-, and multi-offset VSP were applied to assess the applicability of VSP as a method for delineating subsurface structures like magmatic bodies, zones of supercritical fluids, superheated steam, and high permeability in volcanic geothermal fields. Because of high well temperatures (>150°C) and high attenuating surface layers, challenging field preparations were necessary. Three-component seismic data were recorded with a sufficient signal-to-noise ratio and dominant signal frequencies around 20 Hz and 40 Hz, down to 2200 m depth, for air gun and explosive sources, respectively. As a result, the data provide a good basis for several processing and imaging techniques. As part of this Master\'s thesis, standard and novel processing techniques of a subset of the data (zero and far-offset VSP in a single well) have been tested and show promising results in accordance with the lithology from well data. Besides velocity profiles and a corridor stack for both P- and S-waves were determined, a 3D Kirchhoff depth migration and Fresnel volume migration have been applied and tested. Already for a single source location, results show structures in the vicinity and below the well, and it can be assumed that further interpretation and data integration will provide a great potential in addition to hitherto applied teleseismic and potential methods. Especially, for geothermal sites it has been shown, that VSP can be applied and provide information of geometries where dipping faults and fracture zones are expected. The research leading to these results has received funding from the European Community\'s Seventh Framework Programme under grant agreement No. 608553 (Project IMAGE).
654

Simulation expérimentale de l'usure du contact aube-disque de compresseur sous sollicitations de fretting

Mary, Caroline 25 September 2009 (has links)
Lors du fonctionnement d'un turboréacteur, la rotation de l'axe du moteur induit une force centrifuge qui plaque les aubes contre les alvéoles du disque, le long de surfaces appelées « portées ». Au cours de la vie du moteur, des micro-glissements (« fretting ») sont générés au niveau des portées. Ce travail de thèse s'intéresse aux endommagements de type oligocyclique des portées aube/ disque du compresseur Haute Pression (HP) d'un turboréacteur civil. Afin de réduire le frottement et de protéger les pièces, les portées des aubes sont revêtues d'un dépôt épais de CuNiln sur lequel est appliqué un lubrifiant solide. Le système est soumis à des pressions fortes (600MPa) et à des températures élevées (500°C). Des expertises sur pièces ont permis d'identifier des usures importantes et des phénomènes de transfert. Pour simuler expérimentalement le contact, un moyen d'essai de fretting usure en température a été développé dans le cadre de cette thèse. A partir d'une géométrie de contact échelle 1 simplifiée, choisie pour représenter les champs de chargement moteur, le domaine des sollicitations a été balayé et les comportements tribologiques identifiés et caractérisés. L'étude tribologique a permis de mettre en évidence l'influence forte de la force normale sur les mécanismes d'endommagements, dont les scénarios de mise en place ont pu être explicités pour les deux domaines majeurs de sollicitations. Dans un deuxième temps, les endommagements ont été étudiés d'un point de vue physicochimique et le rôle tribochimique joué par les éléments environnementaux (0, N ... ) a été mis en évidence. Pour finir, la comparaison directe des mécanismes identifiés sur banc expérimental et sur le système industriel a permis d'aborder, d'un point de vue critique, l'importance des paramètres choisis pour les équivalences expérience / système industriel ; et de la dynamique de chargement pour garantir la représentativité d'un essai à l'échelle laboratoire. / In the blade/ disk contact of aero-engines, movements induced by the engine regime changes may lead to critical wear. In order to limit friction and protect components, motorists usually use a thick and soft CuNiin layer (150 !-lm) covered with a lubricant. This system is subjected to high contact pressure (upto 600 MPa) and high temperatures (up to 500 °C). In service observations of engine parts revealed significant wear and transfer phenomena. An experimental layout was designed to perform fretting wear tests in temperature on a punch/plane contact, representative of engine solicitation. Based on the tribological study performed, specified gradation mechanisms were identified and the evidence of a pressure threshold was demonstrated. Physicochemical analyses performed confirmed the role played by environment (0, N ... ) in fretting wear mechanisms and suggest that the tribochemical effects should be considered in the fretting wear models. Direct comparisons between degradation mechanisms identified on the experimental system, and on industrial parts, allow a critical review of parameters chosen to simulate the contact. Finally, the impact of loading dynamics was investigated in order to improve tests representativity at la bora tory scale.
655

Právní úprava obnovitelných zdrojů energie / Legal regulation of the renewable energy resources

Bartalská, Katarína January 2011 (has links)
Legal Regulations on Renewable Energy Sources Abstract Submitted thesis presents issues of legal regulations on renewable energy sources emphasizing mainly legal regulations concerning electricity generation of alternative sources. This thesis offers a review of international documents and instruments of international law within a scope of the support of renewable energy sources. Regarding the Czech and Slovak Republic as members of European Union, this thesis also concerns an overview of the European legislation as a tool of integration of energetic markets of single member states and setting binding targets on quota of energy produced from renewable energy sources in the EU member states. Based on the set scientific methods, the thesis describes historical development and basic resources used by creation of legal regulations for renewable energy sources. Using comparative method it summarizes and compares legal regulations on the renewable sources of energy as used in Czech and Slovak legal system. The objective of the thesis is to provide a complex overview of the legal regulation on the renewable sources of energy as the part of environmental law and energy law in the Czech Republic and Slovakia. Keywords: renewable energy sources, environment, energy policy, legal support
656

Makrobiotika - plnohodnotná forma stravování? / Macrobiotic - full-fledged form of food?

Sázavský, Jan January 2012 (has links)
Subject: Macrobiotic - full-valued form of nutrition? Objective: Evaluation of macrobiotics as full compensation for conventional diets recommended by the Presidium of the Board of the Society for Nutrition based on the oretical approaches and empirical findings. Characteristics of the ingredients and nutritional analysis in terms of the in impact on physical and mental condition of the human organism. Method: Objectives of the thesis was achieved using method of quotas to select research sample. On the basis of established criteria and defined number of representatives for the sample, were selected only thoseind ividuals who meet these criteria. Macrobiotic menus were analyzedat three men and at free women. The data obtained via measure ments were compared with recommended daily dose. This model was chosen as it was the most recent vision of the diet model. Results: Macrobiotic diet reprents full-fledged alternative form of nutrition, based on research carried out. This conclusion is based on research conducted with free men and free women who provided weekly menus for analysis purpose and conversion to these menus to the nutritional value was sufficiently proved. Based on the out come of the research, it was found that macrobiotics can not be regarded as nutrition offering full energy, as its...
657

Využití cvičebního programu ve fitness v redukčním období / Use of workout programme in fitness in reduction period

Vrňák, Marek January 2014 (has links)
Title: Use of workout programme in fitness in reduction period Objectives: Objective of diploma thesis is to find out changes in body composition of six clients, who workout in fitness center for five months. Diploma thesis is focused on ganges of fat mass and muscle mass (ATH). Methods: In this thesis was used a method of analysis scientific literature. After that there was used qualitative research by fitness programme, which was used on six clients to find out changes of body composition after five months of workout. The workout was focused on a fitness-strenght workout in fitness centre for five months, consisting of two or three training sessions per week, every training session lasts 60 minutes. Results: Clients consist of 4 men and 2 women. Age of men was in a range of 19 to 49 years, final body weight was in a range of 76kg to 103kg, body height was measured from 174cm to 187cm. Age of women was 45 and 55 years, , final body weight was 75,5kg and 61,9kg, body height was 162cm and 163cm. Men decreased their fat mass in a range of 1,7 to 5,6kg, changes of ATH were measured in a range of +0,6kg to -1kg. Women decreased fat mass 6kg and 2,3kg down, ATH measurement results were +1,1kg and - 1,8kg. The intervention which was based on workout in fitness centre plus changes in nutrition created...
658

Fonctionnalisation de substrats nano-structurés pour la conversion et le stockage de l'énergie / Functionalization of nanostructured substrates for energy conversion and storage

Assaud, Loic 27 September 2013 (has links)
Afin de répondre au besoin de la société actuelle qui utilise toujours plus de moyens de transport et de dispositifs portables, les modes de production, de conversion et de stockage de l'énergie, sont en train de connaître de véritables mutations. Afin de créer des systèmes capables de générer une énergie maîtrisée et renouvelable, les nanosciences et nanotechnologies sont des domaines de premier plan. Le travail présenté dans ce manuscrit décrit la fabrication de structures, de taille nanométrique, organisées à grande échelle. La fonctionnalisation se fait par synthèse de films ou de particules par ALD. Des systèmes MIM sont synthétisés sur des structures ordonnées d'alumine poreuse. Les matériaux déposés en couches minces sont TiN, Al2O3 et HfO2. L'objectif est de fabriquer des nano-condensateurs à hautes performances pouvant être utilisés pour des applications de stockage de données, de mémoire ou pour le stockage d'énergie dans des petits dispositifs comme la technologie RFID.Dans une deuxième partie, des catalyseurs métalliques Pd/Ni sont déposés sur des membranes d'alumine pour l'électro-oxydation de l'acide formique. De la même manière, des nano-tubes de TiO2 fabriqués par oxydation anodique sont fonctionnalisés par des nano-particules de Pd pour l'électrooxydation de l'éthanol. Ces deux études systèmes peuvent conduire à leur utilisation comme catalyseurs au niveau de l'anode des piles à combustible liquide à combustion directe. Enfin, la dernière partie de ce travail consiste au dépôt par voie électrochimique de Cu2O, sur des nano-tubes de TiO2 qui servent de support. La jonction p/n ainsi fabriquée pourra servir pour la photo-conversion de l'énergie solaire. / In order to meet the growing needs in today's society that requests more transportation and portable devices, energy production, conversion and storage systems are now experiencing real changes. To fabricate systems able to generate a controlled and renewable energy, nanoscience and nanotechnology are leading research fields. The work presented in this manuscript describes the fabrication of nanosized, large-scale organized structures. These nanostructures have been functionalized through film and particle synthesis using a chemical vapor deposition method: the Atomic Layer Deposition (ALD).Thus, metal/insulator/metal (MIM) systems are fabricated on highly-ordered high-aspect ratio porous alumina. The materials that have been deposited are TiN, Al2O3 and HfO2. The aim is to produce high performance nanocapacitors that can be used for data storage (DRAM) application or for energy storage in small devices such as RFID.In a second part, metallic catalysts such as Pd/Ni have been deposited on alumina membranes for formic acid electro-oxidation. Similarly, TiO2 nanotubes have been fabricated by anodic oxidation and they have been functionalized with Pd nanoparticles for ethanol electro-oxidation. Both studied systems can be used as anode catalysts in direct liquid fuel cells.Finally, the last part of this work has consisted in the study of Cu2O, as a p-type semiconductor, that has been electrochemically deposited onto TiO2 nanotubes (n-type semiconductor). The resulting p/n junction can be interesting for solar energy photoconversion.
659

Efektivnost výstavby nízkoenergetických bytových domů / Construction efficiency of low-energy residential buildings

Zgúthová, Katarína January 2009 (has links)
Construction of low-energy residential buildings (i.e. houses with low energy demand) in the Czech Republic is not as common as in other countries in the region. This thesis examines the reasons for such development and whether or which obstacles potential buyers face. The analysis of the economic choice between "regular" house and a low-energy building will be primarily based on comparison of basic parameters of both types of constructions. Data for this research will be taken from commercial developers. Quality analysis in the form of detailed interviews with developers, architects and potential buyers will follow. The last section of this thesis will deal with the approach of Czech media towards low-energy development. Presentation of this issue to the public will be examined by the frequency and content of reports.
660

Síťová odvětví v EU / Public Utilities in the EU: Evaluation of Electricity Industry Regulation in the Czech Republic

Hába, Stanislav January 2009 (has links)
The thesis scrutinizes public utilities (network industries) with focus on electricity market regulation. In the first part, a public utility is defined, including its economic characteristics and need for regulation. Within their regulation various models are introduced - in terms of level, voluntary/mandatory, ex ante/ ex post and branch of government. Further, the basic prerequisites for successful regulation are derived from the theory (independence, information capacity and trustworthiness). The second part is concerned only with electrical power industry with its characteristics, business model and regulation (both in the Czech Republic and in the EU). In the third part, an evaluation scorecard is created, which allows us to examine the quality of electricity regulators. The criteria in the scorecard are based on prerequisites (enforcement power, scale of resources, independence, dispute settlement, appeal procedure, transparency and consistency) and results (competition support, renewable energy resources and consumer protection). The model is applied to Energy Regulatory Office (Energeticky regulacni urad) in the Czech Republic.

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