Global ETD Search

1	Encapsulation de dispositifs symbiotiques implantables : évaluation de la biocompatibilité et des performances / Encapsulation of implantable symbiotic devices : evaluation of biocompatibility and performances Penven, Géraldine 11 July 2016 (has links) Afin de répondre à une demande de soins et traitements toujours mieux adaptés et plus performants, des dispositifs médicaux implantables (DMI) ont vu le jour. Il s’agit actuellement de dispositifs isolés et autonomes à l’intérieur de l’organisme hôte, dont la fonction ne nécessite pas d’interaction avec celui-ci, ou uniquement dans un sens (par la libération de molécules par exemple). Une nouvelle génération de DMI dont le fonctionnement s’appuie sur des échanges continus avec l’organisme vivant est toutefois en cours de développement, et un des points clefs de leur élaboration est l’enrobage. En effet, l’interface entre le DMI et le corps joue un rôle primordial puisqu’elle doit assurer une symbiose parfaite entre ces derniers. Les mécanismes inflammatoires et immunitaires étant si complexes et puissants, il est nécessaire de protéger ces dispositifs tout en leur permettant de communiquer avec l’organisme hôte. En outre, cette barrière protège aussi le corps d’éventuels éléments agressifs libérés par l’implant. Ainsi, le travail de recherche décrit dans ce manuscrit concerne la fabrication et la caractérisation d’un matériau qui peut être utilisé pour enrober des dispositifs symbiotiques implantables.Dans ce contexte, les hydrogels d’alcool polyvinylique (Polyvinyl alcohol) : PVA) polymérisés physiquement par un procédé de congélation/décongélation se sont révélés particulièrement intéressants. En effet, leur structure semi-cristalline permet de modifier leur porosité et leurs propriétés mécaniques en faisant varier les paramètres de fabrication. Nous avons donc caractérisé physico-chimiquement les hydrogels de PVA (propriétés mécaniques, porosité, diffusivité), avant d’étudier leur biocompatibilité in vitro et in vivo. Pour finir, nous nous sommes concentrés sur un DMI particulier qu’est la biopile à glucose implantable, en analysant les performances du PVA en tant qu’enrobage d’électrodes.Ainsi, nous avons déterminé un procédé de fabrication permettant d’obtenir une membrane enrobante solide et facile à manipuler, poreuse afin de laisser diffuser le glucose et l’oxygène de manière optimale jusqu’à l’électrode, et protectrice vis-à-vis des protéines de l’organisme de plus grandes tailles. / The development of implantable medical devices (IMD) provides for more efficient treatment in specific healthcare applications. Such devices are isolated and autonomous within the host organism. Their function does not usually require any input from the host, with the main function of the IMD being typically to stimulate tissues (e.g. muscles, nerves) or to release molecules (e.g. osmotic pump). New generations of IMD that rely on the on continuous duplex interactions with the living organism are being developed. The key aspect of such IMD is the interface with the internal environment of the body. This interface plays a crucial role because it must ensure a perfect symbiosis between the IMD and the host. For example, the interface must both protect the IMD from the complex and powerful inflammatory and immune mechanisms in addition to providing an efficient communication pathway with the host organism. Furthermore, this interface also protects the body from the potentially aggressive elements that can be released by the IMD. The research described in this manuscript is focused to the manufacture and characterisation of a material that can be used to coat IMD so as to optimise both the biocompatibility and efficient functions of the IMD.In this context, the research described here has focused on hydrogels of polyvinyl alcohol (PVA) physically polymerized by a freeze/thaw method. Indeed, the semi-crystalline structure of PVA allows modification of the porosity and mechanical properties by varying the parameters of the production process. We therefore performed physico-chemical characterisations of PVA hydrogels (mechanical properties, porosity and diffusivity) before studying in vitro cytotoxicity and in vivo biocompatibility. We tuned the PVA membranes to a specific IMD that relied upon duplex communication for its function (i.e. the implantable glucose biofuel cell) and analyzed the performance of PVA to provide an optimised coating. The results report an optimised manufacturing process for PVA that provides for the IMD (i) a solid and easily handled membrane, (ii) a porous membrane optimised for the diffusion of glucose and oxygen to the IMD bioelectrodes, and (iii) a protective membrane against proteins of larger dimension. Membrane Polymère Biocompatibilité Durée de vie implantable Rendement physiologique Performances énergétiques Membrane Polymer Biocompatibility Implantation lifetime Physiological efficiency Energetic performance 570
2	A influência do sombreamento e da absortância da envoltória no desempenho termoenergético de edifícios residenciais na cidade de Maceió-AL. / The influence of the envelope shading and of the absorptance to the thermalenergetic performance of housing buildings on Maceio AL. Lima, Raffaela Germano de 12 May 2010 (has links) A building constructed according to the climatic characteristics in where it is inserted is important condition to reach thermal comfort and energy saving. However, into the brasilian s housing production predomine standardized architecture models all over the country, wich does not distinct the different local climates, producting, many times, environments without thermal comfort. Factors as the building arrangement, the glazed oppening s dimensions, its exposition to the sun and the thermal properties of the construction materials that compound the buildings envelope are points that define a better thermalenergetic performance. Therefore, this work evaluated the influence of the envelope shading and absorptance to the thermal performance and the energetic consumption of multiple housing buildings situated in Meceió AL having as studing object a model that represents a tipical vertial building tipology developed by PAR Programa de Arrendamento Residencial (Housing Leasehold Program). The methodology is based on parametric analisis in order to compare the reference model to some proposed parameters (solar protection devices, the surroundings and the external walls absorptance), using computer simulation by the EnergyPlus 4.0 software (Energyplus, 2009). To reach the proposed aims there werw vary a parameter by turn, maintaining the other several characteristics of the reference model. The results indicated that the use of solar protection devices and the profit of the building arragement morphology contributed to a better thermal and energetic performance of the building. The predominance of light colors on the external walls was a positive aspect to get fortunate thermal results, thus, is recomended that this characteristic be kept on the city housing programs of Maceio, because it contributed to the energy consumption reduction. / Fundação de Amparo a Pesquisa do Estado de Alagoas / Uma edificação construída de acordo com as características climáticas de onde está inserida é condição importante para a obtenção do conforto térmico e economia energética. Todavia, observa-se que no âmbito da produção habitacional brasileira há a predominância de modelos arquitetônicos padronizados em todo o país, sem distinção quanto às diversidades climáticas locais, produzindo-se muitas vezes ambientes com ausência de conforto térmico. Fatores como a disposição do arranjo construtivo, a dimensão e exposição solar das aberturas envidraçadas e as propriedades dos materiais construtivos que compõem a envoltória são pontos definidores para um melhor desempenho termoenergético de um edifício. Sendo assim, o presente trabalho avaliou a influência do sombreamento e da absortância da envoltória no desempenho térmico e consumo energético em edifícios residenciais multifamiliares localizados em Maceió AL, tendo como objeto de estudo um modelo que representa a tipologia típica de edifício vertical desenvolvido pelo Programa de Arrendamento Residencial PAR. A metodologia fundamentou-se em análises paramétricas visando à comparação entre o modelo de referência e alguns parâmetros propostos (dispositivo de proteção solar, o entorno e a absortância das paredes externas), através de simulações computacionais utilizando o programa EnergyPlus 4.0 (Energyplus, 2009). Para o alcance dos objetivos propostos foi variado um parâmetro por vez, preservando-se as demais características do modelo de referência. Os resultados obtidos indicaram que a utilização de protetor solar e o aproveitamento da morfologia do arranjo construtivo contribuíram para um melhor desempenho termoenergético do edifício. A consideração da predominância da cor clara na textura das paredes externas também foi um aspecto considerado positivo para a obtenção de resultados térmicos favoráveis e que se recomenda que seja mantida nos programas habitacionais para a cidade de Maceió, pois também implicou redução no consumo energético. Thermal energetic performance Housing buildings Shading Absorptance Desempenho termoenergético Edifícios residenciais Sombreamento Absortância
3	Estudo de casos sobre a inércia térmica de edificações na cidade de São Carlos. / Case study of buildings thermal inertia in Sao Carlos, SP. Dornelles, Kelen Almeida 20 April 2004 (has links) Made available in DSpace on 2016-06-02T20:09:14Z (GMT). No. of bitstreams: 1 DissKAD.pdf: 1431161 bytes, checksum: 35e43177014f0202b80650427d7d6613 (MD5) Previous issue date: 2004-04-20 / Financiadora de Estudos e Projetos / In this work, it was investigated the use of thermal inertia in buildings located in Sao Carlos city, SP, which presents semi-humid climate. This research aims to verify the hypothesis that the use of thermal inertia in buildings submitted to the specific climate of Sao Carlos allows to optimize the thermal performance of buildings and to reduce waste of energy to restore indoor thermal comfort. From data obtained by monitoring of seven different buildings, the thermal performance of each one was analyzed when they are submitted to typical simmer and winter conditions. To these seasons, adopting a reference day , it was estimated the heating and cooling requirement to restore the indoor comfort conditions. Besides the analyses for winter and summer seasons, it was estimated the indoor cooling and heating requirement along all moths of the year. Through this analyze, it was possible to verify the real influences of thermal inertia on the indoor comfort conditions. The results indicates that only the use of thermal inertia is insufficient to provide indoor thermal comfort conditions for buildings submitted to the specific climates of Sao Carlos. It is suggested to mach the use of thermal inertia with others passive strategies, in such a way to optimize the thermal performance of buildings. / Neste trabalho, investigou-se o uso da inércia térmica em edificações localizadas na cidade de São Carlos, SP, cujo clima pode se caracterizado como semi-úmido. O objetivo desta pesquisa foi verificar a hipótese de que a utilização da inércia térmica, em edificações submetidas ao clima específico da cidade, permite otimizar o desempenho térmico de edificações e reduzir a necessidade de sistemas artificiais de climatização para restabelece o conforto nos ambientes. Como base nos dados obtidos no monitoramento de ambientes de sete diferentes edificações, analisou-se o desempenho térmico de cada ambiente frente a condições típicas de inverno e verão. Para estes dois períodos, adotando-se um "dia de referência", fez-se o cálculo do desconforto por frio ou calor acumulado ao longo deste dia e se estimou a necessidade de aquecimento e refrigeração, para restabelecer o conforto térmico nos ambientes. Além das análises para inverno e verão, também se estimou a necessidade de aquecimento e refrigeração dos ambientes ao longo de todos os meses do ano. Esta análise permitiu verificar as reais influências da inércia térmica sobre as condições de conforto em edificações, as quais estão submetidas ao clima da cidade de São Carlos. As diversas formas de análise demonstram que apenas a utilização da inércia térmica não é suficiente para oferecer condições de conforto térmico nos ambientes, quando submetidos ao clima específico da cidade. Sugere-se que a utilização da inércia térmica seja combinada com outras estratégias de condicionamento passivo, de tal forma a otimizar o desempenho térmico das edificações. Arquitetura e conservação de energia Inércia térmica Conforto térmico Materiais de construção Thermal inertia Thermal comfort Building systems
4	La construction durable : étude juridique comparative / Maroc-France / Sustainable construction : a comparative legal study / Morocco-France Bouroubat, Khadija 05 December 2016 (has links) La présente étude a pour objet de savoir si le Maroc en tant que pays en voie de développement dispose de dispositifs juridiques lui permettant de construire durablement.Le rapport Meadows publié en 1972 annonçant « les limites de la croissance » a incité la communauté internationale à prendre conscience de l’urgence écologique et à agir. Ainsi, plusieurs conférences internationales ont été organisées afin de mettre en place une nouvelle vision de l’avenir de l’humanité. C’est dans ce contexte international marqué par l’accroissement du conflit entre les préoccupations environnementales et le développement économique que la notion de développement durable a vu le jour. Le secteur de la construction parait-il le mieux à pouvoir intégrer ces préoccupations.Un bâtiment durable doit être pensé dès sa conception. Tout le cycle de vie de l’ouvrage a un impact sur l’environnement. C’est pourquoi son développement est subordonné à l’adoption d’un cadre juridique imposant le recours à des matériaux de construction écologique, à la gestion des déchets, à la préservation de la qualité de l’eau, du sol et de l’air et à la réalisation de la performance énergétique. Ces dispositions impliquent de nouvelles exigences qui vont changer les méthodes et pratiques des intervenants et contribuer à une coopération renforcée dans le cadre de la construction. Ainsi, il sera primordial de mettre la lumière sur la responsabilité de ces professionnels. La construction durable a un coût. Son développement doit être appuyé par des règles d’urbanisme, par des incitations financières et par la normalisation et la certification des bâtiments selon les référentiels de l’association haute qualité environnementale. / This study aims to explore the possibility for Morocco as developing country and booming economy to succeed in integrating sustainable development in the construction sector in the same way as his French counterpart.The Meadows report published in 1972 announcing « the limits togrowth » was intended to encourage international community to become aware of the ecological emergency and to act.Thus, a number of international conférences were organized in order to establish a new vision for the future of humanity. It is in this international context marked by the increase conflict between environmental concerns and economic development that the concept of sustainable development was born. The construction fiel dit seems able to integrate these concerns.A sustainable building must be thought fromits conception. All the life cycle of the work has an impact on the environment.That’s whyhis development is subordinated to the adoption of a legal frame work imposing the use of environment-freindly construction materials, waste management, conservation of the quality of the water, the ground and the air and to realization of the energy performance. These rules involve new requirements which are going to change the methods and the practices and contribute to an enhanced coopération gram work or construction. It is there forevery important to shed light on liability of professionals. Sustainable construction has a cost.It’s development must be supported by rules of urban construction, by Financial incentives and by normalization and certification of buildings according to the reference tables of the high quality environmental association. Construction durable Responsabilité des constructeurs La réglementation thermique La performance énergétique Le droit des déchets Le droit de l'eau Sustainable building Responsibility of manufacturers Thermal regulation Energetic performance The right waste The right to wather
5	Analysis of a novel thermoelectric generator in the built environment Lozano, Adolfo 05 October 2011 (has links) This study centered on a novel thermoelectric generator (TEG) integrated into the built environment. Designed by Watts Thermoelectric LLC, the TEG is essentially a novel assembly of thermoelectric modules whose required temperature differential is supplied by hot and cold streams of water flowing through the TEG. Per its recommended operating conditions, the TEG nominally generates 83 Watts of electrical power. In its default configuration in the built environment, solar-thermal energy serves as the TEG’s hot stream source and geothermal energy serves as its cold stream source. Two systems-level, thermodynamic analyses were performed, which were based on the TEG’s upcoming characterization testing, scheduled to occur later in 2011 in Detroit, Michigan. The first analysis considered the TEG coupled with a solar collector system. A numerical model of the coupled system was constructed in order to estimate the system’s annual energetic performance. It was determined numerically that over the course of a sample year, the solar collector system could deliver 39.73 megawatt-hours (MWh) of thermal energy to the TEG. The TEG converted that thermal energy into a net of 266.5 kilowatt-hours of electricity in that year. The second analysis focused on the TEG itself during operation with the purpose of providing a preliminary thermodynamic characterization of the TEG. Using experimental data, this analysis found the TEG’s operating efficiency to be 1.72%. Next, the annual emissions that would be avoided by implementing the zero-emission TEG were considered. The emission factor of Michigan’s electric grid, RFCM, was calculated to be 0.830 tons of carbon dioxide-equivalent (CO2e) per MWh, and with the TEG’s annual energy output, it was concluded that 0.221 tons CO2e would be avoided each year with the TEG. It is important to note that the TEG can be linearly scaled up by including additional modules. Thus, these benefits can be multiplied through the incorporation of more TEG units. Finally, the levelized cost of electricity (LCOE) of the TEG integrated into the built environment with the solar-thermal hot source and passive ground-based cold source was considered. The LCOE of the system was estimated to be approximately $8,404/MWh, which is substantially greater than current generation technologies. Note that this calculation was based on one particular configuration with a particular and narrow set of assumptions, and is not intended to be a general conclusion about TEG systems overall. It was concluded that while solar-thermal energy systems can sustain the TEG, they are capital-intensive and therefore not economically suitable for the TEG given the assumptions of this analysis. In the end, because of the large costs associated with the solar-thermal system, waste heat recovery is proposed as a potentially more cost-effective provider of the TEG’s hot stream source. / text Thermoelectric generator TEG Novel thermoelectric generator Thermoelectrics Thermoelectric effect Thermoelectric modules Thermoelectric device Patent application Hot stream source Cold stream source EIA EERE Systems-level analysis Energy balance Control volume analysis Thermodynamic analysis Insolation data Insolation incident on a panel Incident insolation Extraterrestrial insolation NREL Ambient temperature data NOAA Renewable energy sources Energy generation technology Electricity generation technology Thermal energy Coupled system Emissions Greenhouse gas GHG Emissions analysis Zero-emission Emissions avoided Emission factor EF Reliability First Corporation RFC Built environment Integrated into the built environment Solar-thermal energy Solar collector system Photovoltaic thermal PVT panel Thermal storage tank Geothermal energy Geothermal heat pump GHP Ground source heat pump GSHP Numerical analysis Numerical model MATLAB Finite-difference Euler explicit Electric grid Annual energetic performance Annual electricity generation Operating efficiency System efficiency Thermodynamic characterization Economic analysis Levelized cost of energy LCOE Waste heat recovery Carbon dioxide equivalent CO2e Capital costs Installed costs Operating and maintenance costs

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