SiC is a hard man-made material and has emerged as an excellent material for a wide range of applications which are exposed to extreme conditions such as high temperatures and harsh chemical environments. These applications range from SiC being used as an abrasive, to a refractory material, to a semiconductor material for high power and high frequency electronic devices. The properties of the material for each application is different, with the semiconductor grade material for electronic devices being the most refined. SiC, with its excellent thermal properties and high resistance to harsh chemical environments, lends itself to being an ideal support for catalyst systems. Various characterisation & analysis techniques such as Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatography (GC) are used in this thesis to investigate the suitability of single crystal SiC for high temperature catalytic systems. Low temperature oxidation of methane was used to investigate the catalytic activity of: Porous and standard 4H-SiC with and without Pd Porous and Standard 6H-SiC with and without Pd. Nanocrystalline Beta-SiC powder with and without Pd. Part of the samples were impregnated with Pd using Palladium Nitrate (Pd (NO3)2) which is a common precursor for Pd. Activation treatments which were investigated were oxidation and reduction. Oxidation was generally better in activating the catalyst, as was expected, since the PdO phase is known to be more active in oxidising methane. A mixed set of Pd and PdO were observed by SEM and EDS which were the main characterisation techniques used to analyze the structure of the catalysts before and after the reaction. The Beta-SiC showed by far the best activity which could be attributed to the micro-crystalline powder format in which it was used, where as all other catalysts studied here were derived from crushed wafer pieces. Type II porous 4H-SiC was another of the samples which registered impressive results, vis-à-vis catalytic activity.

Réseaux locaux. Le mécanisme de communication par bus série auto-alloué. Recoupleur. L'analyseur : outil de mise au point et d'évaluation des systèmes bâtis autour du bus série auto-alloué. Sureté de fonctionnement d'un système reparti bâti autour du mécanisme de communication par bus série auto-alloue.

La popularité des réseaux informatiques et d'Internet s'accompagne d'un essor des applications communicantes et de la multiplication des protocoles dont le fonctionnement est plus ou moins compliqué, ce qui implique également des performances différentes en termes de robustesse. Un premier objectif de cette thèse est d'approfondir plus en détails la robustesse de protocoles s'illustrant par d'extraordinaires performances empiriques tels que les botnets. Différents protocoles employés par les botnets sont donc modélisés dans cette thèse. Par ailleurs, l'essor et la diversité des protocoles s'accompagnent d'un manque de spécification volontaire ou non que la rétro-ingénierie tente de retrouver. Une première phase essentielle est notamment de découvrir les types de messages. La technique mise en \oe uvre dans cette étude s'appuie sur les machines à vecteurs de supports tout en ayant au préalable spécifié de nouvelles représentations des messages dont la complexité de calcul est très réduite par rapport aux autres techniques existantes. Enfin, il existe généralement un grand nombre d'applications distinctes pour un même protocole et identifier précisément le logiciel ou le type d'équipement utilisé (marque, version) est un atout essentiel dans plusieurs domaines tels que la supervision ou la sécurité des réseaux. S'appuyant uniquement sur les types de messages, le comportement d'un équipement, c'est-à-dire la manière dont il interagit avec les autres, est une information très avantageuse lorsqu'elle est couplée avec les délais entre les messages. Enfin, la grammaire d'un protocole connu permet de construire les arbres syntaxiques des messages, dont le contenu et la structure sémantiquement riche, avaient peu été étudiés jusqu'à maintenant dans le cadre de l'identification des équipements.

L'analyse automatique de différences anatomiques en neuroimagerie a de nombreuses applications pour la compréhension et l'aide au diagnostic de pathologies neurologiques. Récemment, il y a eu un intérêt croissant pour les méthodes de classification telles que les machines à vecteurs supports pour dépasser les limites des méthodes univariées traditionnelles. Cette thèse a pour thème l'apprentissage automatique pour l'analyse de populations et la classification de patients en neuroimagerie. Nous avons tout d'abord comparé les performances de différentes stratégies de classification, dans le cadre de la maladie d'Alzheimer à partir d'images IRM anatomiques de 509 sujets de la base de données ADNI. Ces différentes stratégies prennent insuffisamment en compte la distribution spatiale des \textit{features}. C'est pourquoi nous proposons un cadre original de régularisation spatiale et anatomique des machines à vecteurs supports pour des données de neuroimagerie volumiques ou surfaciques, dans le formalisme de la régularisation laplacienne. Cette méthode a été appliquée à deux problématiques cliniques: la maladie d'Alzheimer et les accidents vasculaires cérébraux. L'évaluation montre que la méthode permet d'obtenir des résultats cohérents anatomiquement et donc plus facilement interprétables, tout en maintenant des taux de classification élevés.

States are not required to provide subsidies for childcare and transportation, but at the time of this writing all provided some supplements to TANF participants who were working, looking for work, or attending school. However, there has been little assessment of the effectiveness of these programs. Using data from a longitudinal study on Families First participants in the state of Tennessee, this exploratory study addresses the questions of whether transportation and childcare supplements contribute to the ability of TANF participants to move off welfare and support their families adequately through their own efforts, and whether outcomes from these services differ by geographic location. The survey sample consisted of 3,569 respondents who were currently receiving or who had recently received TANF services through Tennessee's Families First program, beginning with the initial survey in 2001. Regardless of any assistance provided for childcare and transportation, which have been addressed in the literature as significant barriers to employment and thus the well-being of TANF participants, most of the survey participants remain among the poorest families in the country. While transportation and childcare supports may alleviate some of the barriers that TANF participants must overcome, this research finds that they do not in themselves improve the likelihood that poor families will be abot to move out of poverty. However, there are some indicators that they do help in terms of having employment, which is the first step toward achieving financial well-being.

Policies are shaped by social values and assumptions, and can significantly impact the delivery of health and social services. Marginalized groups are often disadvantaged in the political realm and reliant on publicly funded services and supports. The purpose of this research is to consider how public policies are constructed and implemented for marginalized groups and to increase understanding of the consequences of policy reform. It draws on a case study of the Ontario Disability Support Program, Employment Supports (ODSP-ES) and considers the impact of the policy revision that occurred in 2006 on employment support services for people living with mental illness. A constructivist grounded theory approach guided data collection and analysis. Key policy documents were analyzed and 25 key informant interviews were conducted with individuals who were involved in: the construction and/or implementation of the policy; developing and/or delivering employment services under the policy; or advocacy work related to the policy. The findings highlight the impact of outcome-based funding on employment services and practices, and provide lessons for the construction and implementation of public policy for marginalized groups. The new funding system has promoted a shift from a traditional social service model of employment supports towards a marketing model, wherein services focus on increasing job placement and short-term job retention rates. However, the introduction of market principles into employment services has had significant implications for people living with mental illness. Employment programs are required to absorb increased financial risk, thereby altering the way service providers work with clients to help them find and keep jobs; there is a heightened focus on the rapid placement of clients into available jobs and less attention to the quality of employment being achieved and to complex barriers that prevent individuals from succeeding with employment. Although ODSP-ES has been somewhat successful at connecting people with disabilities to competitive employment, it has led to secondary consequences that compromise its overall utility. The findings highlight the complexity of constructing and implementing public policy for marginalized groups and suggest that evaluating public policy is an interpretative exercise that should be explored from multiple perspectives beyond the stated objectives.

Policies are shaped by social values and assumptions, and can significantly impact the delivery of health and social services. Marginalized groups are often disadvantaged in the political realm and reliant on publicly funded services and supports. The purpose of this research is to consider how public policies are constructed and implemented for marginalized groups and to increase understanding of the consequences of policy reform. It draws on a case study of the Ontario Disability Support Program, Employment Supports (ODSP-ES) and considers the impact of the policy revision that occurred in 2006 on employment support services for people living with mental illness. A constructivist grounded theory approach guided data collection and analysis. Key policy documents were analyzed and 25 key informant interviews were conducted with individuals who were involved in: the construction and/or implementation of the policy; developing and/or delivering employment services under the policy; or advocacy work related to the policy. The findings highlight the impact of outcome-based funding on employment services and practices, and provide lessons for the construction and implementation of public policy for marginalized groups. The new funding system has promoted a shift from a traditional social service model of employment supports towards a marketing model, wherein services focus on increasing job placement and short-term job retention rates. However, the introduction of market principles into employment services has had significant implications for people living with mental illness. Employment programs are required to absorb increased financial risk, thereby altering the way service providers work with clients to help them find and keep jobs; there is a heightened focus on the rapid placement of clients into available jobs and less attention to the quality of employment being achieved and to complex barriers that prevent individuals from succeeding with employment. Although ODSP-ES has been somewhat successful at connecting people with disabilities to competitive employment, it has led to secondary consequences that compromise its overall utility. The findings highlight the complexity of constructing and implementing public policy for marginalized groups and suggest that evaluating public policy is an interpretative exercise that should be explored from multiple perspectives beyond the stated objectives.

Students with emotional and behavioral disorders (E/BD) have academic deficits that affect their success in school; however, few researchers have investigated what strategies work best for this population, especially in the area of writing. One promising intervention to support the writing skills of students with and at-risk for E/BD is self-regulated strategy development (SRSD). SRSD is a six-stage, explicit strategy instruction model that includes procedures for goal setting, self-monitoring, self-instruction, and self-reinforcement and can be generalized to a variety of writing tasks. The purpose of this study was to determine the effects of an SRSD persuasive writing intervention on the writing achievement of 44 students in a residential school. Results of a piecewise hierarchical linear modeling growth curve analysis suggest statistically significant gains were made over the course of the intervention in writing (quality, correct word sequences, and essay elements) and academic engagement. Effects also generalized to writing achievement measures. In addition, teachers implemented the intervention with high fidelity, and both students and teachers rated the intervention as socially acceptable, with higher ratings postintervention.

School-Wide Positive Behavior Supports (SWPBS) is a heavily promoted area that focuses on promoting pro-social behavior and preventing misbehavior. Many schools are moving towards SWPBS as the universal level of support for behavior. With Response to Intervention (RtI) being at the forefront of educational reform, this type of universal support is strongly recommended for academic needs, as well as behavioral needs. Data were collected from 25 schools in the West Region of Kentucky that collaborate with the Kentucky Center of Instructional Discipline (KYCID). A series of t-tests were completed in order to examine the relationship between Office Discipline Referrals (ODRs), Benchmark of Qualities (BoQ) scores, and the number of years a school had implemented SWPBS. Location of the ODRs as well as behaviors that led to ODRs were also examined. The findings of this study indicate that the longer a school has implemented SWPBS, the fewer ODRs it has during a school year. Also, BoQ’s were positively impacted the longer SWPBS was in place at a school. Regarding problem behavior, it was found that ODRs came primarily from a classroom environment as opposed to common areas (bathroom, hallway, cafeteria, and playground). A descriptive analysis was completed on the types of ODRs most commonly found in classroom settings, and it was discovered that the top three reasons for ODRs were defiance, fighting, and disruptive behavior. These findings can be used to guide schools on school-wide expectations and classroom management practices, as well as to affirm the continued implementation of SWPBS from year to year.

Cables are highly nonlinear structural members under transverse loading. This nonlinearity is mainly due to the close relationship between the final geometry under transverse loads and the resulting stresses in its equilibrium state rather than the material properties. In practice, the cables are usually used as isolated single-segment elements fixed at the ends. Various studies and solution procedures suggested by researchers are available in the literature for such isolated cables. However, not much work is available for continuous cables with multiple supports. In this study, a multi-segment continuous cable is defined as a cable fixed at the ends and supported by a number of stationary roller supports in between. Total cable length is assumed constant and the intermediate supports are assumed to be frictionless. Therefore, the critical issue is to find the distribution of the cable length among its segments in the final equilibrium state. Since the solution of single-segment cables is available the additional condition to be satisfied for multi-segment continuous cables with multiple supports is to have stress continuity at intermediate support locations where successive cable segments meet. A predictive/corrective iteration procedure is proposed for this purpose. The solution starts with an initially assumed distribution of total cable length among the segments and each segment is analyzed as an independent isolated single-segment cable. In general, the stress continuity between the cable segments will not be satisfied unless the assumed distribution of cable length is the correct distribution corresponding to final equilibrium state. In the subsequent iterations the segment lengths are readjusted to eliminate the unbalanced tensions at segment junctions. The iterations are continued until the stress continuity is satisfied at all junctions. Two alternative approaches are proposed for the segment length adjustments: Direct stiffness method and tension distribution method. Both techniques have been implemented in a software program for the analysis of multi-segment continuous cables and some sample problems are analyzed for verification. The results are satisfactory and compares well with those obtained by the commercial finite element program ANSYS.