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Renewable and available in abundance, incident solar radiation is an ideal candidate for energy production. The development of nanostructured coatings for the improve- ment of technologies that convert solar energy into heat and electricity opens interesting new perspectives for the future. This PhD thesis presents an approach based on iterative cycles for the development and optimisation of such materials with a view to industrial scale production. Two ap- plications are investigated : chromium-free black selective coatings for durable thermal solar absorbers and orange coloured interferential filters for photovoltaic collectors with a view to their architectural integration. The first part of this work describes in detail the different production stages of the black selective coating from the preparation of the solutions to the manufacturing of a prototype. According to our study, the optimal coating for stainless steel tubes with a length of two meters is composed of a superposition of thin layers of Cu-Co-Mn-O//Cu- Co-Mn-Si-O//Si-O applied through sol-gel technology and annealed by an innovative induction heating process for which a patent request has been filed. The nanocomposite coating has the advantage of combining the optical properties αsol = 0.93 and εth = 0.12 with durability properties that make it eligible for possible industrialisation. The second part of the thesis describes the production of orange coloured interferen- tial filters applied on photovoltaic collectors through magnetron sputtering, a process for which another patent application has been filed. The obtained samples meet the expectations of the market with regard to such a product with a relative performance reduction of 10 to 15% in comparison with an identical collector without a filter. An in- dustrial prototype of 1190 mm x 412 mm has been produced and is being characterised at the moment these lines are written.

Keywords: Daylighting ; electricity ; energy saving ; buildings ; anidolic reflector ; lightdeflector ; light-duct ; solar protection ; blinds ; visual comfort ; thermal comfort ; seasonal selectivity ; Eclairage naturel ; electricite ; economie d'energie ; bâtiment ; reflecteur anidolique ; deflecteur lumineux ; conduit lumineux ; protection solaire ; store ; confort visuel ; confort thermique ; selectivite saisonniere These Ecole polytechnique federale de Lausanne EPFL, n° 2026 (1999)Faculte de l'environnement naturel, architectural et construitLaboratoire d'energie solaire et physique du bâtimentJury: Raphael Compagnon, Markus Hubbuch, Theo Lasser, Juan Carlos Minano, Claude Morel, Jean-Pierre Stoeckli Public defense: 1999-9-9 Reference doi:10.5075/epfl-thesis-2026Print copy in library catalog Record created on 2005-03-16, modified on 2016-08-08

Réalisation emblématique du « Plan Neige » français de 1964, la station touristique d'Avoriaz résulte d'un projet initié par un promoteur privé et encadré par une convention d'aménagement signée avec la commune de Morzine. Le réseau d'eau d'Avoriaz s'est ainsi construit ex-­‐nihilo en suivant le développement de la station touristique et sous la responsabilité de l'aménageur. Celui-­‐ci, propriétaire des infrastructures durant l'étendue de la convention d'aménagement, a ensuite délégué la gestion du réseau à un opérateur privé. Il en résulte une double-­‐délégation de service impliquant des acteurs public et privé. Cette communication analyse les effets de cette double-­‐délégation sur, d'une part, les modalités de gestion des réseaux et, d'autre part, sur la capacité de pilotage de l'action publique pour la gestion du réseau et de la ressource en eau. Iconic Achievement of the French « Plan Neige », the resort of Avoriaz is the result of a project initiated by a private promoter and framed by a management agreement signed with the city of Morzine. As a result, the water network has been built ex-­‐nihilo following the development of the resort and under the responsibility of the promoter. The latter, owner of the infrastructure in the scope of the management agreement delegated the water network management to a private operator. The result is a double delegation involving public and private actors. This paper presents the analyses of effects of such double-­‐delegation firstly on network's governance modalities and secondly on the steering capacities of public authority over water network and water resources management.

Les changements climatiques liés au réchauffement planétaire comportent des enjeux cliniques majeurs. Nous nous concentrerons sur les enjeux cardiovasculaires et rénaux. Les adaptations physiologiques et effets physiopathologiques sont décrits, particulièrement chez des populations vulnérables. Les conséquences cliniques des vagues de chaleur sont en grande majorité cardiovasculaires. Les accidents vasculaires cérébraux, cardiopathies ischémiques aiguës et morts subites sont augmentés jusqu’à 40 %. De même, les épisodes d’insuffisance rénale aiguë, les troubles électrolytiques et les lithiases rénales augmentent. Le risque d’insuffisance cardiaque et le nombre d’insuffisances rénales chroniques augmentent également dans les régions tropicales. Les médecins doivent être conscients de ces conséquences pour lesquelles ils seront impliqués à l’avenir. Climate change and global warming present major clinical challenges. We focus on cardiovascular and renal clinical consequences. The physiological adaptations and physiopathological effects are described, especially in vulnerable populations. The clinical consequences during heat waves, are mainly cardiovascular with stroke, acute ischemic heart disease and sudden death increased by up to 40%. Likewise, episodes of acute renal failure, electrolyte disturbances and kidney stones disease increase. The chronic consequences should not be overlooked, as the risk of heart failure also increases in high ambient temperature regions and there is also some evidence of an increase in chronic kidney disease in tropical zones. Physicians must be aware of these consequences as they will be involved in their management in the future.

This thesis aims to examine the causal mechanisms of living environments on leisure mobilities and verify whether their inclusion is actually able to challenge the compact city as a sustainable urban form. The research focuses on the Swiss case and in particular the cities of Geneva and Zurich. The empirical approach is based on three types of additional analysis carried out in these areas: contextual analysis, quantitative analyzes based on data from the Mobility and Transport Microcensus 2010 and qualitative analysis through interviews. The main results are the following: â ¢ We find the existence of two opposing logics of association between land density and distance traveled: a decreasing link to daily mobility, but a positive correlation for occasional mobility (day trips and overnight trips). The denser is the living environment, the greater is the distance for this mobility. â ¢ Adding the two types of mobility to obtain a total average, we find that the inner city dwellers displayed, ultimately, much higher totals than would suggest the analysis of their daily mobility alone which therefore represent an invitation to invalidate the link compact city=short distances. â ¢ By transforming these distances into environmental impact, however, our calculations show that even while taking into account the many trips of urban dwellers, the negative relationship between total energy consumption and land density of the territory remains. â ¢ By examining in detail the share of leisure in daily and occasional mobility, we see that the logic of compensation is not what structures the links with urban environnements. In everyday life, the logic of proximity prevails: to live in the centre is rather correlated to more compactophile leisure and residing in the periphery to more leisure oriented towards the attributes of nature. â ¢ For occasional trips, we show firstly that compactophile mobilities represent a large part of these practices among all respondents, and secondly, that even in the case of very important and high energy consuming naturophile mobility, the relationship with the density of the living environment is not established. The central Genevans and are much less consumers of this type of leisure than people in the centre of Zurich even though their city is much more airy and green. Moreover, we also highlight, in peri-urban dwellers, a very intense mobility or this purpose. â ¢ The interpretation that we propose refers to lifestyles and residential choice of city dwellers which takes into account their leisure aspirations. These tastes are then translated into specific leisure activities and travel. In everyday life, they rely on proximity and functional, social and sensitive attributes of their living environment that they have chosen largely also for this. When it comes to breaking the routines during holidays and vacations, the same lifestyles result in significant occasional mobility whose motives can register in continuity of their daily lifestyle (loving the same things elsewhere) or by contrast (appreciate the diversity of spaces). In both cases, these motivations echo the valorisation of the diversity inherent in urbanity without questioning the urban residential location quality itself. Our results lead us ultimately to reject the compensation effect hypothesis and reaffirm, against the defenders of the sprawl-city, the virtues of the compact city, which remains a sustainable urban form, including for our leisure mobility.

Etude du degré d'attention de 3 quotidiens de Suisse, Le Temps, La Tribune de Genève et Le Courrier au changement climatique, au réchauffement climatique et aux gaz à effet de serre durant la période janvier 2006-décembre 2015. Analyse quantitative des variations d'attention au problème social récurrent avec des périodes de forte attention et de déclin. Regain d'attention surtout durant les conférences de la Convention-cadre des Nations-Unies sur le changement climatique et les réunions internationales de groupes de pays. Analyse qualitative de contenu par ordinateur des thèmes dominants, mots-clés, sources, pays mentionnés, points d'ancrage et cadres médiatiques thématiques ou rhétoriques. L'explication de la causalité et du rôle humain dans les changements climatiques occupe une importance moindre par rapport aux conséquences, enjeux géostratégiques et solutions proposées.

Keywords: district heating network ; heat load ; tree-shaped or meshed configuration ; pumping energy ; modifications ; extension ; simulation ; pipe diameters ; discounting values ; combinatory optimisation ; knowledge-based rules ; chauffage a distance ; reseaux ; demande thermique ; configuration maillee ou arborescente ; energie de pompage ; modifications ; extension ; simulation ; diametres de conduites ; couts actualises ; optimisation combinatoire ; regles basees sur des connaissances These Ecole polytechnique federale de Lausanne EPFL, n° 1304 (1994)Chaire de recherche operationnelle SOGroupe GnansounouJury: F. Bosshard ; P.-A. Haldi ; Th. Liebling ; Y. Smeers ; I. Smith Reference doi:10.5075/epfl-thesis-1304Print copy in library catalog Record created on 2005-03-16, modified on 2016-08-08