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Les travaux de thèse portent sur la réalisation de capteurs à fibre optique protégés par un revêtement résistant aux hautes températures, supérieures à 350 °C. Une partie des travaux est réalisée sur tour de fibrage dans l’optique d’améliorer la fiabilité mécanique de ces capteurs compacts.Les premiers travaux présentés se focalisent sur l’étude microstructurale par microscopie électronique à transmission de réseaux de Bragg point par point inscrits par un laser femtoseconde. Les observations démontrent un gradient chimique du germanium au niveau des modifications périodiques. Ce gradient expliquerait en partie les évolutions spectrales de ces capteurs à 1000 °C.La deuxième étude montre le potentiel des fibres dopées en nanoparticules de zircone pour les mesures réparties à 800 °C par réflectométrie fréquentielle exploitant la rétrodiffusion Rayleigh. Ces fibres présentent une meilleure stabilité de mesure de température que les fibres classiquement employées pour la télécommunication optique.La troisième étude porte sur la protection mécanique des fibres optiques par un revêtement « hautes températures ». Pour la première fois, les silicones chargées sont étudiées comme revêtement pour fibre optique. Le comportement du revêtement est étudié jusqu’à 470 °C à l’aide de réseaux de Bragg protégés par dip-coating. Le revêtement est aussi déposé sur fibre lors de sa fabrication sur tour de fibrage. Plus de 100 mètres de fibre sont protégées en continu avec une épaisseur d’environ 13 µm. / The Ph.D. work focuses on the realisation of optical fibre sensors protected by a high-temperature resistant coating. The aim application temperature is above 350 °C. One part of the work is done on a fibre draw tower to improve the mechanical reliability of these compact sensors.The first part of the presented work focuses on the microstructural study of point-by-point fibre Bragg gratings. These gratings are inscribed in the optical fibre core with a femtosecond laser. The analysis by transmission electronic microscopy shows germanium chemical gradient near the periodic modifications. This gradient could partially explain the spectral evolutions of these sensors at 1000 °C.The second study shows the performances of zirconia nanoparticle-doped optical fibres for distributed sensing at 800 °C by Optical Frequency Domain Reflectometry. These fibres have a better stability of temperature measurement than conventional fibres for optical telecommunication.The third study is related to the mechanical protection of optical fibres by a high-temperature resistant coating. For the first time, a silicone coating with fillers is studied like a coating for optical fibre. The coating is applied on fibre Bragg gratings by dip-coating to study the behaviour of the coating on the fibre up to 470 °C. Then the coating is applied on an optical fibre by using a fibre draw tower. A 100 meter-length fibre is protected with a thickness of around 13 µm.

Each year the top 125 players on the PGA TOUR money list receive fully exempt status for the upcoming season. Past literature looks at the determinants that led to success for the top professionals on the PGA TOUR. Instead, I look at the determinants of finishing inside the top 125 on the PGA TOUR money list and retaining one’s TOUR card. I analyze the difference both statistically and in future earnings between finishing 100-125th on the money list and 126-150th. This paper finds that greens and regulation and putting have the largest effect on retaining a TOUR card while driving distance and accuracy are significant but at a much lower level. Future studies should look into the tradeoff between playing on the PGA TOUR and less marque tours like the Web.com as it can affect one’s earnings greatly.

Tour guides are one of the most visible players in tourism but little scholarly attention has been given to the links that tour guides may have with sustainable development. This study addresses the gap by promoting an understanding of how tour guides can assist in moving tourism in a sustainable direction. Sustainable development is expected to improve the quality of life for all people without causing undesirable ecological and socio-cultural outcomes. As a central agent in the entire tourism system, tour guides have a variety of roles to play in response to the expectations of the various tourism stakeholders. A literature review suggests that tour guides can contribute to destinations'sustainable development by exerting their functions on experience management, resources management and local economic promotion. Interpretative guiding is the means by which tour guides can realize these above potentials. A case study was conducted in Hainan, China. The guiding performance there was examined to see whether and to what extent tour guides are contributing to the achievement of local sustainability. It was discovered that the tour guides in Hainan do not exert (well) their expected functions either in enhancing enjoyable experiences for tourists, in supporting local resource conservation, or in promoting the healthy development of the local economy. Their potentials are blocked by the issues and problems of instant money-making-centered guiding conduct, below-cost group receiving industry practices and unfair remuneration system for the guides, absence of protection measures to ensure the guides??? interests, opportunism in guiding and lenient certificating requirements, lack of professionalism and effective training, ineffective monitoring measures, and limited awareness of sustainable development. In order to better the situation, unhealthy travel and trade industry practice should be banned; effective certificating, training and monitoring measures should be developed and implemented; tour guides??? personal interests should be protected and local awareness of sustainability, in particular that of the industry members, should be fostered. Serious efforts of the government administration as well as industry members and tour guides are required if tour guides are to fulfill their potential as agents of sustainable development.

Nous adaptons la définition des sections de Postnikov et des tours de Postnikov des ensembles simpliciaux aux opérades simpliciales. Nous définissons ensuite des foncteurs de cotroncation afin de filtrer la tour de Postnikov d’une opérade simpliciale par les arités et former ainsi la double tour de Postnikov de cette opérade. Nous introduisons un nouveau type d’opérade, les gamma-opérades, où gamma désigne une opérade dans les groupoïdes. Nous les utilisons pour modéliser l’action de l’opérade groupoïde fondamental d’une opérade simpliciale sur ses groupes d’homotopies et son revêtement universel. Nous munissons la catégorie des gamma-opérades d’ensembles simpliciaux d’une structure de catégorie modèle. D’autre part, nous montrons que les gamma-opérades dans la catégorie des groupes abéliens munie de la structure monoïdale induite par la somme directe forment une catégorie abélienne. Cette catégorie abélienne fournit les coefficients pour la cohomologie équivariante opéradique que nous étudions ensuite. Une version relative de cette cohomologie est également étudiée. Nous définissons alors les invariants de Postnikov d’une opérade simpliciale. Ce sont des classes de cohomologie équivariante opéradique qui permettent de reconstruire inductivement et à homotopie près une opérade simpliciale à l’aide de sa double tour. Ce processus de reconstruction est utilisé afin de développer une théorie de l’obstruction pour les opérades simpliciales : on peut étendre un morphisme d’opérades simpliciales le long d’une cofibration si et seulement une suite de classes de cohomologie équivariante opéradique relative définie inductivement est nulle. / We adapt the definition of Postnikov sections and Postnikov towers of simplicial sets to simplicial operads. We then define cotruncation functors in order to filter the Postnikov tower of a simplicial operad by arity and form the Postnikov double tower of this operad. We introduce a new kind of operad, the gamma-operads with gamma a groupoid operad. We use them to model the action of the fundamental groupoid operad of a simplicial operad on its homotopy groups and its universal covering. We equip the category of gamma-operad in simplicial sets with a model structure. We also prove that the gamma-operads in the category of abelian group equipped with the monoidal structure induced by the direct sum form an abelian category. This abelian category provides the coefficients for the operadic equivariant cohomology we study afterward. Furthermore, we study a relative version of this cohomology. We thereafter define the Postnikov invariants of a simplicial operad. These are operadic equivariant cohomology classes which permit to reconstruct inductively and up to homotopy a simplicial operad by the mean of its double tower. This reconstruction process is used to develop an obstruction theory for simplicial operads : a simplicial operad morphism can be extended along a cofibration if an only if a sequence of relative operadic equivariant cohomology classes defined inductively vanishes.

Nous rappelons les fondements de l’arithmétique des classes logarithmiques, puis démontrons des résultats sur la capitulation des classes logarithmiques, en particulier un analogue du théorème 94 de Hilbert. Un algorithme de calcul du groupe de capitulation logarithmique est donné. Dans cette même perspective de principalisation des diviseurs logarithmiques, nous obtenons des conditions de finitude et d’infinitude de la tour localement cyclotomique d’un corps de nombres, concept initié par Jean-François Jaulent et Florence Soriano-Gafiuk. Les théorèmes montrent le rôle fondamental de la ramification logarithmique dans l’opposition à la principalisation . Une généralisation de cette tour est proposée, ainsi qu’une caractérisation de sa finitude / We present the foundations of logarithmic arithmetic and prove results about capitulation of logarithmic class, particularly a logarithmic version of Hilbert’s Theorem 94. We also give an algorithm to compute the kernel of the logarithmic capitulation. In the same view of principalization for logarithmic divisors, we obtain conditions for both finitude and infinitude of the locally cyclotomic tower constructed by Jean-François Jaulent and Florence Soriano-Gafiuk. The theorems shows the fundamental part of logarithmic ramification opposed to the phenomenon of principalization. We investigate a generalization of the locally cyclotomic tower and give a characterization for the finitude

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Truckload shipments constitute a significant portion of the freight transportation industry. In recent years, truckload industry is facing a serious problem of high driver turn over rate. In this research, we present a mathematical model for multi-zone dispatching method to solve this issue. Multi-zone dispatching is a method in which a service area is divided into many zones. Truckload within a zone is carried by local drivers and the truckload between zones is carried by lane drivers. Apart from reducing the driver tour length to a desirable level, the model for multi-zone also contains some unique constraints to address some issues from the perspectives of the company and the customer. The binary integer program is solved by exact methods. As the problem size increases, exact methods fail quickly. Hence, a construction heuristic within tabu search framework is developed to solve the model. Analysis of various parameters concerned is provided to gain better insights of varied aspects of the problem. Computational results for analysis of parameters and comparison of exact and heuristic methods are provided.

No description available.

Truckload shipments constitute a significant portion of the freight transportation industry. In recent years, truckload industry is facing a serious problem of high driver turn over rate. In this research, we present a mathematical model for multi-zone dispatching method to solve this issue. Multi-zone dispatching is a method in which a service area is divided into many zones. Truckload within a zone is carried by local drivers and the truckload between zones is carried by lane drivers. Apart from reducing the driver tour length to a desirable level, the model for multi-zone also contains some unique constraints to address some issues from the perspectives of the company and the customer. The binary integer program is solved by exact methods. As the problem size increases, exact methods fail quickly. Hence, a construction heuristic within tabu search framework is developed to solve the model. Analysis of various parameters concerned is provided to gain better insights of varied aspects of the problem. Computational results for analysis of parameters and comparison of exact and heuristic methods are provided.