4,937 Works

Contribution à l'étude du comportement thermo-hydraulique du stockage de chaleur en aquifère

Stéphane Dupasquier
In this work, a parametric study is done with computational methods for groundwater flow and heat transport in order to describe the dominant physical phenomena in an Aquifer Thermal Energy Storage (ATES). Optimum operating conditions and geological parameters are deduced from it. The intended use of the ATES is the domestic water or space heating. The stock is seasonal and functions without heat pump. Parametric study is organized as a series of reference simulations relating...

Elucidating the Role of Quaternary Structure in Modulating Macrophage Migration Inhibitory Factor (MIF) Functions

Farah El Turk
Macrophage Migration Inhibitory Factor (MIF) is a multifunctional protein and a major mediator of innate immunity. The paramount importance of MIF in the pathogenesis of many inflammatory, infectious, auto-immune and oncogenic diseases led to its emergence as a viable therapeutic target. Understanding MIF' biological and structural properties is of fundamental importance to provide insights into the molecular bases underlying its mode of action, and to develop effective strategies to diagnose, prevent or treat MIF associated...

Broadcast Encryption and Traitor Tracing for Conditional Access Systems

Alexandre Karlov
In the context of the thesis we are studying the notions of broadcast encryption and traitor tracing in an industrial framework of conditional access systems related to Pay-TV. Broadcast encryption represents a cryptographic primitive which allows confidential transmission of content on a broadcast channel in such a way that only an authorized subset of users defined by the broadcaster are able to access it. Traitor tracing is a mechanism for identifying rogue sources who shared...

Precipitation and transformation of nanostructured copper oxalate and copper/cobalt composite precursor synthesis

Lucica Cristina Soare
The aim of this thesis was to synthesise and control a nanostructured composite of copper/cobalt. Both the copper and cobalt oxalate exhibit a nanostructure. Attempts to produce nanocomposite particles in the size range of 10-70 nm were made via an oxalate co-precipitation route followed by the appropriate thermal treatment to finally obtain the metal nanocomposite. Much attention was focussed on the understanding of the copper oxalate precipitation and its further transformation into metal before the...

Wireless sensor networks for marginal farming in India

Jacques Panchard
In this dissertation, we explore the potential of wireless sensor networks (WSNs) in an original context, the small agriculture of Developing Countries (DCs). Our goal is to confront an emerging technology with a concrete problem of world-wide dimensions, the sustainability of farming for small land-holders living in conditions of water scarcity. Based on a survey about information needs, we design a series of precise use cases, provide system design, implementation and deployment guidelines for the...

High temperature mechanical spectroscopy of fine-grained zirconia and alumina containing nano-sized reinforcements

Claudia Ionascu
Polycrystalline zirconia (3Y-TZP grade) unreinforced and reinforced with multiwalled carbon nanotubes (CNTs) or silicon carbide whiskers (SiCw) or silicon carbide particles (SiCp) have been processed and studied by mechanical spectroscopy with complementary observations of electron microscopy and creep tests. Moreover, for comparison with zirconia, polycrystalline alumina specimens, unreinforced and reinforced with silicon carbide nanoparticles, have also been studied. The high-temperature mechanical loss spectrum of pure zirconia presents an exponential background (exponential increase with temperature) accompanied...

Distribution management system including dispersed generation and storage in a liberalized market environment

Elvira Kägi-Kolisnychenko
Distribution systems are now fundamentally changing. This is due to the fact that a lot of small size dispersed generation units (DG) are expected to be installed at the distribution level, that is, in the medium voltage (MV) and low voltage (LV) networks [1.1]. The problems arise from the current design features of distribution networks, which were not supposed to include energy sources. At this level, until now, the energy is bought from the wholesale...

Comportement du ballast sous l'action du bourrage et du trafic ferroviaire

Chiara Paderno
The geometry of the railway track is degraded under traffic load, and must be maintained periodically. This degradation is due to the arrangement of ballast particles under loads and vibrations, which results into irreversible plastic settlements. Tamping is a procedure of maintenance, used to restore the correct geometrical position of the ballasted tracks. However, the penetration of the vibrating tines into the ballast causes an increase in the fine particles content by rupture of the...

The Notch signaling pathway:hair graying and pigment cell homeostasis

Karine Schouwey
In animals, pigment cells are essential for coloration, as seen in feathers, fur, skin and eyes. In mammals, neural crest-derived melanocytes constitute the major population of pigment cells that is located mainly in the skin epidermis, as well as in hair follicles. A minor population of pigment cells originates from the optic cup and forms the retinal pigment epithelium (RPE), a cell monolayer lying between the neural retina and the choroid. In many cell types,...

Analysis of the Pigment Cell Specific Gene MART-1/Melan-A/mlana:Expressional Regulation and Function

Iraz Toprak Aydin
Pigmentation is a complex process that provides many diverse benefits for the organism. Pigment production takes place in the pigment cell lineage in dedicated organelles called melanosomes. Several proteins are specifically recruited to melanosomes for this purpose, and many of them are involved in melanin synthesis. MART-1 is one of the melanosomal proteins. It has been widely studied as an agent for immunotherapy against malignant melanoma but very little is known about the gene and...

Choix de variantes d'infrastructures routières:méthodes multicritères

Micaël Tille
This study provides a tool by means of which a road planner, usually a civil engineer, can achieve a durable infrastructure of high quality, acceptable to all parties concerned. The various elements which facilitate the work of planning are united into a modernized methodology for the elaboration of road projects, called a methodology of concert. After analysing the sort of problems encountered in the planning of road infrastructure (Chapter 1), the author classifies the main...

Déformations des couches bitumineuses au passage d'une charge de trafic

Jacques Perret
Undertaken in the field of design methods for flexible pavement, the present study focuses on the introduction of traffic loads, applied mainly to mechanistic empirical methods. In such research, strains due to traffic loads — calculated by pavement modeling based on linear elastic theory — are used for the evaluation of the life duration of the pavement. Real traffic loads on pavement vary significantly according to their intensity as well as their application modes. Our...

Modélisation et prédiction du comportement rhéologique des mélanges bitume caoutchouc

Mehdi Ould Henia
Asphalt rubber is a modified binder widely used in pavement construction. Composition design methods of asphalt rubber blends are exclusively empiric and rely on the selection of the optimal combination of parameters after a long experimental program. The understanding of the phenomena affecting the asphalt rubber behaviour starts with the proposal of a rational theory and its validation with experimental data. To do so, a set of experiments were carried out including three main factors...

A methodology (CUPRITE) for urban network travel time estimation by integrating multisource data

Ashish Bhaskar
Travel time is an important network performance measure and it quantifies congestion in a manner easily understood by all transport users. In urban networks, travel time estimation is challenging due to number of reasons such as, fluctuations in traffic flow due to traffic signals, significant flow to/from mid-link sinks/sources, etc. In this research a methodology, named CUmulative plots and PRobe Integration for Travel timE estimation (CUPRITE), has been developed, tested and validated for average travel...

Elaboration d'un système de navigation auto-alimenté (SNA) et évaluation de ses performances

Alexandre Torday
This research deals with self-supplied navigation systems (SNS), a combination of the technology of gathering travel time using floating car data (FCD) and dynamic route guidance (DRG). Using similar on-board equipment, these two systems can easily be combined in the same vehicle. The main goal is to prove the relationship between the percentage of SNS-equipped vehicles and the performance that can be expected from the use of this technology. After the description of the SNS...

Dynamic urban origin-destination matrix estimation methodology

Emmanuel Bert
The aim of this thesis is to develop a new methodology to determine dynamic Origin-Destination (OD) matrices for urban networks characterized by a high number of traffic hubs, complex route choice possibilities and a high level of traffic controls. By reviewing existing methods, from static to dynamic OD matrix evaluation, deficiencies in the approaches are identified: mainly, the level of detail of the traffic assignment for complex urban networks and the lack in dynamic approaches....

Sur quelques inclusions différentielles de premier et de deuxième ordre

Gisella Croce
The principal subject of this thesis is the study of some Dirichlet problems related to differential inclusions of first and second order. We have studied the two following problems : where E ⊂ R2×2 is a compact isotropic set and where We show some existence theorems of W1,∞ and W2,∞ solutions respectively. Moreover we have studied a minimization problem : the computation of α(p, q, r) defined by

Multiscale modelling of metabolism and transport phenomena in living tissues

Carlo D'Angelo
The range of applications of mathematical modelling in biosciences has recently expanded to encompass problems posed by biomedicine and sport sciences. Topics of interest are for instance the prediction of the response of an athlete to exercise, the pharmacokinetics of a chemical compound, or the detection of illicit drugs. In this work, we consider some of these problems, related to metabolism, circulation and mass transport in tissues. First, we address the quantitative analysis of the...

Shape design by optimal flow control and reduced basis techniques:applications to bypass configurations in haemodynamics

Gianluigi Rozza
The purpose of this thesis is to develop numerical methods for optimization, control and shape design in computational fluid dynamics, more precisely in haemodynamics. The application studied is related with the shape optimization of an aorto-coronaric bypass. The optimization process has to keep into account aspects which are very different and sometimes conflicting, for this reason the process has been organized in more levels dealing with a geometrical scale. Moreover we have chosen to use...

Domain decomposition methods for the coupling of surface and groundwater flows

Marco Discacciati
The purpose of this thesis is to investigate, from both the mathematical and numerical viewpoint, the coupling of surface and porous media flows, with particular concern on environmental applications. Domain decomposition methods are applied to set up effective iterative algorithms for the numerical solution of the global problem. To this aim, we reformulate the coupled problem in terms of an interface (Steklov-Poincaré) equation and we investigate the properties of the Steklov-Poincaré operators in order to...

Stabilization strategies for discontinuous Galerkin methods

Benjamin Stamm
The subject of this thesis is the analysis of discontinuous Galerkin methods for linear partial differential equations of first or second order. Discontinuous Galerkin methods are known to satisfy a local mass conservation property. Taking a closer look one can observe that this property often depends on the method itself, i.e. on some method-dependent parameters. The main objective of this work is to design discontinuous Galerkin schemes satisfying a method-independent local mass conservation property still...

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