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Thermochemical storage systems prove to be good alternatives to current technologies for seasonal or inter-seasonal storage of heat, because energy is stored as a chemical potential and therefore, there is no heat loss during the storage period. Nowadays, a large number of studies have been conducted on the development of thermochemical reactor integrated in the storage system, andlittle study has been conducted on reactor technologies separated from the storage system. The latter, however, have the advantage, among others, of separating the thermal power produced or consumed and the storage capacity of the installation, which would increase the storage density.This study investigates the development of a moving-bed thermochemical reactor operating with hydrated salts and humid air cross-flow, suitable for district heating applications. A reactor prototype, developed and built during this study, allowed to analyze the functioning of the reactor. This study has, among others, highlighted the impact of the preferential air flow path on the reactorperformances (temperature and power), as well as the importance of the air humidity at the reactor inlet on these performances.In addition, two mathematical models have been developed : a 1D analytical model and a 2D model taking into account the heat and mass transfer phenomena within the reactive area. The 2D model, validated with the experimental results, was exploited using the finite element simulation software COMSOL Multiphysics to conduct a theoretical study on the functioning and the performances of the reactor. This numerical study focused on the influence of operating conditions (air flow rate and moisture content, solid flow rate) on the performances and the efficiency of the system and allowed the comparison of moving bed reactor over fixed bed reactors, commonly developed for thermochemical storage applications. This study has shown the importance of solid velocity control for optimizing the performances of the moving bed reactor.This study has highlighted ...

Ce texte s'interroge sur la stabilité du régime climatique de Rio-Kyoto. Il vise à fournir une réponse à la question de substance qui est posée : la défection des USA n'ayant manifestement pas empêché la création du régime international, peut-elle néanmoins le déstabiliser à court ou moyen terme ? Mais il vise aussi, dans une perspective d'Economie Politique Internationale, à répondre à la question suivante : la négociation climat augure-t-elle de la fin de l'âge réaliste dans les relations internationales ?

The aim of this thesis is to offer a characterization of terminological variation and neology around the topic of Anthropogenic Climate Change (ACC), taking into account the role and implications of these two linguistic phenomena in relation to climate objectives. What is at stake is a better understanding of the role that terms, on the one hand, and terminology as a discipline, on the other hand, can play in addressing the climate issue. Climate change, as a transdisciplinary subject of study and a topic of debate among different social groups, does not constitute a prototypical research theme in terminology. The first part of this thesis is thus dedicated to defining a specialized domain of climate change and demonstrating the benefits of studying the latter from a variationist perspective, considering neology as a form of variation. In the second part, we combine tools from Textual Terminology and Discourse Analysis to identify a specialized terminology of ACC and demonstrate how it evolves over time and how it tends to vary among climate experts, specifically between intergovernmental organizations (IGOs) and non-governmental organizations (NGOs). In a final section, we examine variation between these two expert communities and the press, and question the existence of a climate terminology specific to the latter, in line with the transdisciplinary nature of the ACC domain. For each form of variation under study, we present its potential implications in relation to the purpose of this domain, defined as revolving around three major objectives: reducing gaps in climate change knowledge, disseminating this knowledge, and taking climate action. ; L'objectif de la thèse est de proposer une caractérisation de la variation terminologique et de la néologie autour du changement climatique d’origine anthropique (CCA) en tenant compte du rôle et des implications de ces deux phénomènes linguistiques vis-à-vis des objectifs climatiques. L’enjeu de ce projet est une meilleure compréhension du rôle que peuvent jouer les ...

This PhD thesis contributes to the power management in buildings. It is shown that, by providing appliances with optimization algorithms and communication abilities, it is possible to improve energy consumption and production in buildings by exploiting the degrees of freedom coming from user requests and appliance behaviors. A mathematical formulation and a multi-layer control architecture composed of three layers: predictive, reactive and local layers, are proposed in order to optimize user's comfort, economical and environmental criterion. Different solving approaches based on hybrid metaheuristics and dynamic programming are proposed. A multi-parametric programming is used to take into account big uncertainties. It has been applied to the power management of a photovoltaic building and to the prevention of blackouts using sets of buildings equipped with intelligent and communicating home automation systems. ; Le travail présenté contribue à la gestion de la consommation et de la production d'énergie dans le bâtiment. L'objectif est de montrer qu'en dotant les équipements domotiques d'algorithmes d'optimisation et de facultés de communication, il est possible de mieux maîtriser la consommation dans le bâtiment en exploitant les degrés de liberté offerts par l'usager et ceux liés au fonctionnement des équipements. Une formulation mathématique et une architecture de conduite structurées en trois niveaux : prédictif, réactif et local, sont proposées dans le but d'optimiser le confort de l'usager, les coûts économiques et environnementaux. Plusieurs approches de résolution à base de métaheuristiques hybrides et de programmation dynamique sont proposées. La programmation multiparamétrique est utilisée pour la prise en compte des grosses incertitudes. Ces résultats ont été appliqués à la gestion d'énergie d'un bâtiment photovoltaïque et à la prévention de blackouts par un délestage intelligent.

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WITH THE ADVANCES OF INSTRUMENTS DEDICATED TO MOLECULAR ASTRONOMY MADE DURING THE PAST DECADES AND FORTHCOMING (HERSCHEL AND ALMA), MORE AND MORE MOLECULES ARE DISCOVERED, AND OBSERVED SPECTRA BECOME MORE AND MORE PRECISE. FOR A GOOD UNDERSTANDING OF THESE DATA, ONE NEEDS STATE-TO-STATE COLLISIONAL RATES FOR THE OBSERVED MOLECULES. THE PRECISION OF RATES IS ONE OF THE KEY POINTS OF THIS THESIS: AT THE SAME TIME, WE SEEK THE MAXIMUM PRECISION AND CHARACTERIZE THE NEED AND COST OF PRECISION IN THE CALCULATIONS WE MAKE. CO-H2 IS A SYSTEM OF GREAT ASTROPHYSICAL INTEREST, PREVIOUSLY WIDELY STUDIED. WE SHOW ON THIS SYSTEM THE EQUAL IMPORTANCE OF THE MAIN STEPS OF THE CALCULATION IN THE FINAL PRECISION OF THE RATES. ON HC3N-H2, WE ACHIEVE FOR THE FIRST TIME A FIT OF THE POTENTIAL ENERGY SURFACE (PES) ON A SPHERICAL BASIS ALLOWING US TO CARRY OUT, ALSO FOR THE FIRST TIME, QUANTUM SCATTERING CALCULATIONS. STRONG QUANTUM SELECTION RULES ARE OBTAINED (ABSENT AT THE CLASSICAL LEVEL). THEY SHOULD PLAY A ROLE IN THE ASTROPHYSICAL MODELING OF THIS MOLECULE. THESE RESULTS ARE IN PRINCIPLE TRANSPOSABLE TO ANY LARGE LINEAR MOLECULE. FINALLY, WE BUILD FOR H2O-H2 A NINE-DIMENSIONAL PES, INCLUDING ALL VIBRATIONS. THE ORIGINAL AND AND PRECISE FIT OF THIS SURFACE ALLOWS US TO RULE ON THE OPTIMAL CHOICE OF GEOMETRIES FOR RIGID MOLECULES, AS WELL AS TO COMPUTE ROVIBRATIONAL RATES. THE LATTER, BEING ONE ORDER OF MAGNITUDE LARGER THAN THE PREVIOUS DATA, WILL CHANGE THE INTERPRETATION OF OBSERVATIONS, NOTABLY THOSE OF THE FORTHCOMING HERSCHEL SPACE TELESCOPE. ; AVEC LES PROGRES DES INSTRUMENTS DEDIES A L'ASTRONOMIE MOLECULAIRE REALISES DURANT LES DERNIERES DECENNIES ET A VENIR (HERSCHEL ET ALMA), TOUJOURS PLUS DE MOLECULES SONT OBSERVEES, ET LES SPECTRES OBTENUS SONT DE PLUS EN PLUS PRECIS. POUR INTERPRETER CES DONNEES, IL FAUT NOTAMMENT DES TAUX DE COLLISION D'ETAT A ETAT POUR LES MOLECULES OBSERVEES. LA PRECISION DES TAUX EST UN DES POINTS CENTRAUX DE CETTE THESE. CECI, AUSSI BIEN DANS LA RECHERCHE D'UN MAXIMUM DE PRECISION QUE DANS LA ...

In order to reach commercialization, organic photovoltaic solar cells need to reach efficiencies above 10 % and achieve lifetimes of several thousands of hours. Tandem solar cells are a way of improving the efficiencies. The objectives of this work are therefore to study the fabrication process, the operation and the ageing of organic tandem solar cells. First, single solar cells based on the active material PCDTBT are used as model to investigate the factors governing the cells efficiencies. Using characterization techniques such as impedance spectroscopy, the roles played by each layer of the cells are identified. Based on these results, a protocol to make series tandem cells is developed. Each of its steps is dedicated to treating a key aspect of tandem cells : choice of complementary absorbing polymers, design of the intermediate layer (IML) and thickness optimization. The functioning of the IML is subjected to a particular attention. To optimize the thicknesses, optical phenomena are numerically simulated. The prediction thus made are then compared to experimental results. Finally, the ageing of single and tandem cells is investigated on time spans ranging from several dozens to several thousands of hours. It is shown that the device degradation can be linked to poor ageing of the interface layers, while the active layer stays stable. Organic tandem cells are promising candidates to reach both high efficiencies and long lifetime. ; Pour être viable économiquement, les cellules photovoltaïques organiques doivent dépasser 10 % de rendement et atteindre plusieurs milliers d'heure de durée de vie. Les cellules tandems constituent une voie probante d'augmentation des rendements. Ce travail de thèse a pour objectifs l'élaboration de cellules organiques tandems puis l'étude de leur fonctionnement et de leur vieillissement. Dans un premier temps, les paramètres gouvernant le rendement de cellules photovoltaïques organiques sont examinés sur le modèle de cellules simples à base de PCDTBT. Des caractérisations ...

To better reduce its invoices, control its energy flows and respect various restrictions in this sector characterised by important consumption, the building becomes more and more complex including various innovative technologies such as Energy Management Systems (BEMS), efficient insulation and integrating renewable energies. This complexity requires a changing in building simulation techniques and paradigms in order to take into account its various developments. A global modelling of this system taking into account its various components and ensuring an efficient simulation of its heterogeneous subsystems must be performed.These objectives can only be achieved through the use of interoperability methodological approaches. Several interoperability solutions have been explored in the building sector and the state of the art make an accent on the standardization lack of applied solutions. A white box approach based on Modelica language has emerged in this area. To raise its interest and limitations, this solution is adopted for “PREDIS” system, a high energy performance building, modelling. A complementary black box approach, based on software component standard and dedicated for simulation is also applied to overcome the first approach difficulties. This approach is based on software component bus concept that is able to ensure an effective interoperability between modelling tools and simulation environments.In addition of the established software architecture around the platform interoperability, an efficient simulation of heterogeneous systems requires appropriate simulations techniques. These techniques may require several adaptations of used models that are provided by the component standard. ; Pour mieux maîtriser ses flux énergétiques et respecter les diverses restrictions mises en place dans ce secteur énergivore, le bâtiment devient un système de plus en plus complexe incluant divers technologies innovantes comme les systèmes de gestion énergétiques (SGEB), une isolation performante et intégrant les ...

Photovoltaic (PV) cells, for solar modules or panels, are protected from environmental stresses by polymeric encapsulants, which are mostly crosslinked elastomers. The optimization and the control of the encapsulation step have a twofold interest by increasing PV module lifetime and productivity, thus leading to a decrease of the cost of generated electricity. Two main directions have been investigated in this work: 1) The first one is related to the study of the crosslinking degree of the main industrial PV polyolefin encapsulant, EVA, which is a copolymer composed of ethylene and vinyl acetate, used currently in film form. Indeed, poor crosslinking level can lead to its creep, impacting directly the module lifetime. To overcome this problem, the quality control needs to be improved, by the evaluation of the crosslinking degree obtained while using the conventional encapsulation process (through lamination of encapsulant foils). Thus, the comparison of several methods to evaluate this degree are led ;2) The second direction concerns the study of a new encapsulation process. Indeed, the conventional lamination process potentially creates mechanical stresses in the PV cells, which as a consequence may limit the PV module lifetime. Moreover, lamination requires a relatively long processing time. To overcome this problem, the development of a new encapsulation process using a photopolymerizable encapsulant, initially liquid, decreases the production costs of PV modules and potentially increases their lifetime. The rheology properties and the polymerization kinetics of the new encapsulant are studied. At the end of the present work, both encapsulation processes are compared. Electrical performances of PV cells are measured before and after encapsulation as well as before and after ageing cycles. It has been revealed that the new encapsulation process presents at least as good, if not better performances than the standard process, thus highlighting its big potential for the manufacturing of PV modules ; Les cellules ...