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Thesis (Ph. D.)--State University of New York at Binghamton, Department of System Science and Industrial Engineering, 2005. / Includes bibliographical references.

Thesis (M.S.)--Rochester Institute of Technology, 1994. / Typescript. Includes bibliographical references (leaves 103-104).

La nanostructuration des matériaux thermoélectriques semble être la solution pour palier au faible rendement généralement rencontré chez ces matériaux. Bien qu’il y ait eu de nets progrès en manipulant de nouvelles formulations et en nano-structurant les composés existants, peu de travaux ont été entrepris sur la fabrication de dispositifs permettant la micro-génération ou le micro-refroidissement thermoélectrique. Dans ce contexte, les travaux de recherche ont été en premier lieu l’optimisation et la maitrise de la croissance par voie électrochimique de réseaux auto-ordonnés de nanofils thermoélectriques à base de tellurure de bismuth de type n (Bi2Te3-xSex) et de type p (BixSb2-xTe3) dans des membranes d’alumine nanoporeuses. Les propriétés structurales et thermoélectriques de ces nanofils ont été investigués. Concernant les caractérisations électriques, une nouvelle méthode de mesure sur nanofil unique dans sa membrane a été développée. Elle permet de s’affranchir des problèmes d’oxydation quand le fils est libéré de sa membrane dans les méthodes de mesure classiques. La conductivité thermique a aussi été estimée sur des fils dans leurs membranes avec la méthode 3-omega. La deuxième partie de la thèse a été consacré à des premiers essais d'assemblage des deux types pour évaluer la performance d’un prototype de thermogénérateur (TEG) fonctionnant à une température proche de l’ambiante. Et en parallèle une étude des problèmes de résistance de contact entre le métal et le thermoélectrique a été réalisée. / Nanostructuration of thermoelectric materials seems to be the solution for their low efficiency generally encountered. Even if fair progress have been realized in manipulation of new formulations and nanostructuration of existing materials, few studies have been undertaken to develop devices for thermoelectric micro-generation or micro-cooling. In this context, bismuth antimony telluride (BixSb2-xTe3) and bismuth tellurium selenide (Bi2Te3-xSex) nanowires, have been potentiostatically electrodeposited using anodic alumina membrane. Nanowires structure, stoichiometry and thermoelectric properties have been investigated. A new method for electrical characterization have been developed, consisting in direct electrical transport measurement on a single nanowire embedded in his matrix. This method avoid oxidation effects and time-consuming processing as nanowires need no preliminary preparation and remain in their template during measurement. Thermal conductivity was also investigated using 3-omega method. The second part of this work was dedicated to first tests on n-type and p-type assembly in order to study the efficiency of TEG prototype working at ambient temperature. In parallel, a study of contact resistance (thermoelectric / metal) have been conducted.

Representation theory is the study of abstract algebraic structures by representing their elements as linear transformations or matrices. It provides a bridge between the abstract symbolic mathematics and its explicit applications in nearly every branch of mathematics. Combinatorial representation theory aims to use combinatorial objects to model representations, thus answering questions in this field combinatorially. Combinatorial objects are used to help describe, count and generate representations. This has led to a rich symbiotic relationship where combinatorics has helped answer algebraic questions and algebraic techniques have helped answer combinatorial questions. In this thesis we discuss the representation theory of the symmetric group and the general linear group. The theory of these two families of groups is often considered the corner stone of combinatorial representation theory. Results and techniques arising from the study of these groups have been successfully generalized to a very wide class of groups. An overview of some of the generalizations can be found in [BR99]. There are also many avenues for further generalizations which are currently being explored. The constructions of the Specht and Schur modules that we discuss here use the concept of Young tableaux. Young tableaux are combinatorial objects that were introduced by the Reverend Alfred Young, a mathematician at Cambridge University, in 1901. In 1903, Georg Frobenius applied them to the study of the symmetric group. Since then, they have been found to play an important role in the study of symmetric functions, representation theory of the symmetric and complex general linear groups and Schubert calculus of Grassmannians. Applications of Young tableaux to other branches of mathematics are still being discovered. When drawing and labelling Young tableaux there are a few conflicting conventions in the literature, throughout this thesis we shall be following the English notation. In chapter 1 we shall make a few definitions and state some results which will be used in this thesis. In chapter 2 we discuss the representations of the symmetric group. In this chapter we define the Specht modules and prove that they describe all the irreducible representations of Sn. We conclude with a discussion about the ring of Sn representations which is used to prove some identities of Specht modules. In chapter 3 we discuss the representations of the general linear group. In this chapter we define the Schur modules and prove that they describe all the irreducible rational representations of GLmC. We also show that the set of tableaux forms an indexing set for a basis of the Schur modules. In chapter 4 we describe a relation between the Specht and Schur modules. This is a corollary to the more general Schur-Weyl duality, an overview of which can be found in [BR99]. The appendix contains the code and screen-shots of two computer programs that were written as part of this thesis. The programs have been written in C++ and the data structures have been implemented using the Standard Template Library. The first program gives us information about the representations of Sn for a given n. For a user defined n it will list all the Specht modules corresponding to that n, their dimensions and the standard tableaux corresponding to their basis elements. The second program gives information about a certain representation of GLmC. For a user defined m and λ it gives the dimension and the semistandard tableaux corresponding to the basis elements of the Schur module Eλ .

International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Advanced Airborne Test Instrumentation System (AATIS), one of the major instrumentation systems in use today by the Department of Defense (DoD), was developed in the late 1980's to improve and modernize its predecessor - the Airborne Test Instrumentation System (ATIS). Use of AATIS, by not only the Air Force but the Navy and Army, has improved instrumentation commonality and interoperability across multiple test programs. AATIS, developed by the same manufacturer as the DoD Common Airborne Instrumentation System (CAIS), has a common bus structure - enabling cross utilization of many components which will ease transition from one system to another. The objective of this paper is to provide an overview on the Advanced ATIS System and its logistics support concept. For system description, an overview is presented on the airborne system and related ground support equipment. A brief description is given on the three levels of maintenance being used or planned for by the using activities. Finally, a projection is presented on the utilization of this system for the next 3 years.

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Le principal objectif de la thèse est l'étude des relations entre les différents espaces des moduIes provenant de connections sur des fibrés vectoriels sur des variétés algébriques. Les classes suivantes de connections sont considérées: la classe des connections méromorpbes avec diviseur de pôles fixè D et ses sous-classes des connections intégrables, connections logarithmiques intégrables et connections logarithmiques intégrables avec une structure parabolique sur D. La question la plus fascinante est la relation entre l'espace des modules des connections et celui des fibrés vectoriels sous-jacents. L'application naturelle oubliant la seconde composante de la paire (fibré vectoriel, connection) est bien définie uniquement au-dessus du lieu des fibrés vectoriels semistables, puisque uniquement ceux-ci ont une théorie de modules conséquente. La première partie de la thèse fournit un exemple pratique d'une famille de connections logarithmiques de rang 2 sur une courbe elliptique, pour laquelle la question de la (semi)stabiIilé des fibrés vectoriels sous-jacents est complètement résolue. Les connections logarithmiques sous considération sont les images directes de connections régulières sur des fibrés en droites au-dessus de revêtements doubles de genre 2 de la courbe elliptique, appelés bielliptiques. Nous donnons une paramétrisation explicite de telles connections, déterminons leur monodromie et leur groupe de Galois différentiel. Le fibré vectoriel sous-jacent de rang 2 est décrit en termes de transformées élémentaires et d'applications birationnelles des surfaces réglées. Dans la seconde partie, nous construisons les espaces de Kuranishi (ou déformations verselles) pour les quatre classes de connections. Les espaces tangents et les espaces d'obstructions de la théorie des déformations sont définis comme l'hypercohomologie d'un complexe approprié de faisceaux, et l'espace de Kuranishi est une fibre de l'application d'obstruction formelle. Dans la troisième partie, nous esquissons la construction de GlT des espaces des moduIes pour les quatre classes de connections et utilisons le théorème des slices étales de Luna pour représenter le germe de l'espace des moduIes des connections comme le quotient de l'espace de Kuranishi par le groupe des automorphismes de la fibre centrale. Cette méthode est utilisée pour déterminer les singularités de l'espace des modules des connections dans des exemples, en particulier, ceux provenant des courbes bielliptiques. / The logarithmic connections studied in Chapter 1 are direct images of regular connections on line bundles over genus-2 double covers of the elliptic curve. We give an explicit parametrization of ail such connections, determine their monodromy, differential Galois group and the underlying rank-2 vector bundle. The latter is described in terms of elementary transforms. The question of its (semi)-stability is addressed. ln Chapter 2, we construct the Kuranishi spaces (or versai deformations) for the four connection classes: the class of meromorphic connections with fixed divisor of poles D and its subclasses of integrable. integrable logarithmic and integrable logarithmic connections with a parabolic structure over D. ln Chapter 3, we use the Kuranishi spaces to describe the local structure of the moduli spaces of connections and their relation to the moduli spaces of underlying vector bundles.

Abstract In this thesis, the fabrication and performance of the OC-48 optical transceiver modules applied in optical communication network are studied. The optical transceiver modules consist of two parts¡Gthe transmitter and receiver. In the transmitter, laser driver IC and 1310nm FP (Fabry-Perot) Laser are used. In the receiver, limiting amplifier IC and 1310nm ROSA (Receiver Optical Sub-Assembly) are introduced. The static response of L-I curve and dynamic responses of VNA (Vector Network Analyzer) are studied. The effective bandwidth of LD can be observed from dynamic response. These parameters can help us to determine the LD driver for use in high frequency operation. Then, the method of DC-Coupling circuit to drive IC can be successfully transferred to optical signal. The operation conditions of an OC-48 transceiver module are the laser output power of -6dBm, signal pattern of 27-1, and data rate of 2.5Gb/s. The result of eye diagram measurement can meet the mask of ITU-T standards with the deterministic jitter of 49.88ps (0.1247 UI).¡CAfter 1 meter fiber transmission, the receiver can meet ITU-T standard with deterministic jitter of 125.28ps (0.3132 UI). In the future, the receiver should be improved to get a lower deterministic jitter.