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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

I OPT OUT: UNDERSTANDING THE IMPACT OF RACE, SELF-LIMITING BEHAVIOR, AND MOTIVATIONAL PERSISTENCE ON SELF-EFFICACY AND INTENTIONS TO BE AN ATHLETICS DIRECTOR

Merrill, Miriam Gwendolyn January 2019 (has links)
Barriers for women in athletics administration have been examined by researchers to understand such barriers through a multi-level approach (Cunningham, 2010; Taylor & Wells, 2017). Research suggests barriers exist at a macro-level with gender discrimination (Schull, Shaw, & Kihl, 2013), homologous reproduction and hegemony (Knoppers, 1989; Regan & Cunningham, 2012). Examples of occupational segregation (Whiteside & Hardin, 2010) define barriers at the meso-level, and variables, such as self-efficacy, exist at the micro-level for women in male-dominated fields (Marra, Rodgers, Shen, & Bogue, 2009). The purpose of this study was to examine the relationship between self-limiting behavior and the intent to pursue the athletics director position, as well as the relationship between motivational persistence and the intent to pursue the athletics director position. The potentially mediated relationship of self-efficacy between these relationships was also investigated. The target population was female senior-level administrators at FBS and FCS institutions. Additionally, the aim was to understand if race moderates the relationship among self-efficacy, self-limiting behavior, and motivational persistence for female senior-level athletics administrators at FBS institutions. Lastly, the research sought to understand the differences between African American and White female senior-level administrators and their perceptions of self-efficacy, self-limiting behavior, and motivational persistence and intentions to pursue the athletics director position. Ninety-seven female senior-level athletic administrators were surveyed with 11 of those participants completing an in-depth interview. Seventy-five percent of the women surveyed do not plan on becoming a director of athletics at an FBS institution; however, 44% indicated they would pursue an NCAA Division I FCS or Division I - AAA athletics director position at some point. In other words, there is more of an interest to pursue the athletics director position at a less powerful institution. The data also suggested African American women in senior-level administration positions report higher self-limiting behaviors and higher self-efficacy than White women. Moreover, race was found to be a moderator between self-efficacy and intention to pursue the FBS athletics director position. Qualitative interviews from 11 women were conducted for analysis of experiences. Four major themes emerged from the data: Assets, resources, micro-level challenges, and macro-level challenges. Limitations including small sample size as well as unreliable measures for self-limiting behavior were discussed. The current study suggests that self-efficacy is important when it comes to intentions to pursue the athletics director position. It is also important to note the racial differences between groups as it relates to self-efficacy and intentions. Keywords: athletic administration, self-efficacy, racial differences, women, career intentions / Kinesiology
132

General Weighted Optimality of Designed Experiments

Stallings, Jonathan W. 22 April 2014 (has links)
Design problems involve finding optimal plans that minimize cost and maximize information about the effects of changing experimental variables on some response. Information is typically measured through statistically meaningful functions, or criteria, of a design's corresponding information matrix. The most common criteria implicitly assume equal interest in all effects and certain forms of information matrices tend to optimize them. However, these criteria can be poor assessments of a design when there is unequal interest in the experimental effects. Morgan and Wang (2010) addressed this potential pitfall by developing a concise weighting system based on quadratic forms of a diagonal matrix W that allows a researcher to specify relative importance of information for any effects. They were then able to generate a broad class of weighted optimality criteria that evaluate a design's ability to maximize the weighted information, ultimately targeting those designs that efficiently estimate effects assigned larger weight. This dissertation considers a much broader class of potential weighting systems, and hence weighted criteria, by allowing W to be any symmetric, positive definite matrix. Assuming the response and experimental effects may be expressed as a general linear model, we provide a survey of the standard approach to optimal designs based on real-valued, convex functions of information matrices. Motivated by this approach, we introduce fundamental definitions and preliminary results underlying the theory of general weighted optimality. A class of weight matrices is established that allows an experimenter to directly assign weights to a set of estimable functions and we show how optimality of transformed models may be placed under a weighted optimality context. Straightforward modifications to SAS PROC OPTEX are shown to provide an algorithmic search procedure for weighted optimal designs, including A-optimal incomplete block designs. Finally, a general theory is given for design optimization when only a subset of all estimable functions is assumed to be in the model. We use this to develop a weighted criterion to search for A-optimal completely randomized designs for baseline factorial effects assuming all high-order interactions are negligible. / Ph. D.
133

Enhancing Patient-Professional Communication About End-of-Life Issues in Life-Limiting Conditions: A Critical Review of the Literature

Barnes, S., Gardiner, C., Gott, M., Payne, S., Chady, B., Small, Neil A., Seamark, D., Halpin, D. 12 1900 (has links)
No / Context. The End of Life Care Strategy for England highlights effective communication between patients and professionals as key to facilitating patient involvement in advance care planning. The strategy emphasizes that, currently, communication in patients with noncancer life-limiting conditions is likely to be inadequate, and research has identified that patients with chronic obstructive pulmonary disease and heart failure have a poor understanding of their condition. Objectives. To identify existing interventions of patient-professional communication developed for life-limiting conditions and explore the applicability of interventions developed within a cancer framework to other diagnostic groups. Methods. A comprehensive literature review of studies describing communication interventions for patients receiving end-of-life care was undertaken. Ten electronic databases were searched. Inclusion criteria were all English language studies relating to patient-professional communication interventions for patients with life-limiting conditions receiving end-of-life care. Results. Of the 755 articles initially identified, 16 met the inclusion criteria. Three core themes emerged from the synthesis of the literature: using education to enhance professional communication skills, using communication to improve patient understanding, and using communication skills to facilitate advance care planning. Conclusion. Although limited, evidence relating to the development and evaluation of communication interventions for patients with life-limiting illnesses would suggest that a successful intervention should include combined components of training, patient discussion, and education. In a context of limited resources and an increasing number of patients living and dying with chronic life-limiting conditions, the need for appropriate and effective communication strategies should be seen as a priority for both research and policy.
134

A systematic review of the relationships between social capital and socioeconomic inequalities in health: a contribution to understanding the psychosocial pathway of health inequalities

Uphoff, E.P., Pickett, K.E., Cabieses, B., Small, Neil A., Wright, J. January 2013 (has links)
Yes / Recent research on health inequalities moves beyond illustrating the importance of psychosocial factors for health to a more in-depth study of the specific psychosocial pathways involved. Social capital is a concept that captures both a buffer function of the social environment on health, as well as potential negative effects arising from social inequality and exclusion. This systematic review assesses the current evidence, and identifies gaps in knowledge, on the associations and interactions between social capital and socioeconomic inequalities in health. Through this systematic review we identified studies on the interactions between social capital and socioeconomic inequalities in health published before July 2012. The literature search resulted in 618 studies after removal of duplicates, of which 60 studies were eligible for analysis. Self-reported measures of health were most frequently used, together with different bonding, bridging and linking components of social capital. A large majority, 56 studies, confirmed a correlation between social capital and socioeconomic inequalities in health. Twelve studies reported that social capital might buffer negative health effects of low socioeconomic status and five studies concluded that social capital has a stronger positive effect on health for people with a lower socioeconomic status. There is evidence for both a buffer effect and a dependency effect of social capital on socioeconomic inequalities in health, although the studies that assess these interactions are limited in number. More evidence is needed, as identified hypotheses have implications for community action and for action on the structural causes of social inequalities.
135

高温超伝導バルク導体を用いた超伝導限流変圧器の開発に関する研究

早川, 直樹, 大久保, 仁, 加藤, 克巳, Juengst, Klaus-Peter 03 1900 (has links)
科学研究費補助金 研究種目:基盤研究(A)(2) 課題番号:14205040 研究代表者:早川 直樹 研究期間:2002-2003年度
136

Distribution spectrale limite pour des matrices à entrées corrélées et inégalité de type Bernstein / Limiting spectral distribution for matrices with correlated entries and Bernstein-type inequality

Banna, Marwa 25 September 2015 (has links)
Cette thèse porte essentiellement sur l'étude de la distribution spectrale limite de grandes matrices aléatoires dont les entrées sont corrélées et traite également d'inégalités de déviation pour la plus grande valeur propre d'une somme de matrices aléatoires auto-adjointes et géométriquement absolument réguliers. On s'intéresse au comportement asymptotique de grandes matrices de covariances et de matrices de type Wigner dont les entrées sont des fonctionnelles d'une suite de variables aléatoires à valeurs réelles indépendantes et de même loi. On montre que dans ce contexte la distribution spectrale empirique des matrices peut être obtenue en analysant une matrice gaussienne ayant la même structure de covariance. Cette approche est valide que ce soit pour des processus à mémoire courte ou pour des processus exhibant de la mémoire longue, et on montre ainsi un résultat d'universalité concernant le comportement asymptotique du spectre de ces matrices. Notre approche consiste en un mélange de la méthode de Lindeberg par blocs et d'une technique d'interpolation Gaussienne. Une nouvelle inégalité de concentration pour la transformée de Stieltjes pour des matrices symétriques ayant des lignes $m$-dépendantes est établie. Notre méthode permet d'obtenir, sous de faibles conditions, l'équation intégrale satisfaite par la transformée de Stieltjes de la distribution spectrale limite. Ce résultat s'applique à des matrices associées à des fonctions de processus linéaires, à des modèles ARCH ainsi qu'à des modèles non-linéaires de type Volterra. On traite également le cas des matrices de Gram dont les entrées sont des fonctionnelles d'un processus absolument régulier (i.e. $beta$-mélangeant).On établit une inégalité de concentration qui nous permet de montrer, sous une condition de décroissance arithmétique des coefficients de $beta$-mélange, que la transformée de Stieltjes se concentre autour de sa moyenne. On réduit ensuite le problème à l'étude d'une matrice gaussienne ayant une structure de covariance similaire via la méthode de Lindeberg par blocs. Des applications à des chaînes de Markov stationnaires et Harris récurrentes ainsi qu'à des systèmes dynamiques sont données. Dans le dernier chapitre de cette thèse, on étudie des inégalités de déviation pour la plus grande valeur propre d'une somme de matrices aléatoires auto-adjointes. Plus précisément, on établit une inégalité de type Bernstein pour la plus grande valeur propre de la somme de matrices auto-ajointes, centrées et géométriquement $beta$-mélangeantes dont la plus grande valeur propre est bornée. Ceci étend d'une part le résultat de Merlevède et al. (2009) à un cadre matriciel et généralise d'autre part, à un facteur logarithmique près, les résultats de Tropp (2012) pour des sommes de matrices indépendantes / In this thesis, we investigate mainly the limiting spectral distribution of random matrices having correlated entries and prove as well a Bernstein-type inequality for the largest eigenvalue of the sum of self-adjoint random matrices that are geometrically absolutely regular. We are interested in the asymptotic spectral behavior of sample covariance matrices and Wigner-type matrices having correlated entries that are functions of independent random variables. We show that the limiting spectral distribution can be obtained by analyzing a Gaussian matrix having the same covariance structure. This approximation approach is valid for both short and long range dependent stationary random processes just having moments of second order. Our approach is based on a blend of a blocking procedure, Lindeberg's method and the Gaussian interpolation technique. We also develop new tools including a concentration inequality for the spectral measure for matrices having $K$-dependent rows. This method permits to derive, under mild conditions, an integral equation of the Stieltjes transform of the limiting spectral distribution. Applications to matrices whose entries consist of functions of linear processes, ARCH processes or non-linear Volterra-type processes are also given.We also investigate the asymptotic behavior of Gram matrices having correlated entries that are functions of an absolutely regular random process. We give a concentration inequality of the Stieltjes transform and prove that, under an arithmetical decay condition on the absolute regular coefficients, it is almost surely concentrated around its expectation. The study is then reduced to Gaussian matrices, with a close covariance structure, proving then the universality of the limiting spectral distribution. Applications to stationary Harris recurrent Markov chains and to dynamical systems are also given.In the last chapter, we prove a Bernstein type inequality for the largest eigenvalue of the sum of self-adjoint centered and geometrically absolutely regular random matrices with bounded largest eigenvalue. This inequality is an extension to the matrix setting of the Bernstein-type inequality obtained by Merlev`ede et al. (2009) and a generalization, up to a logarithmic term, of Tropp's inequality (2012) by relaxing the independence hypothesis
137

A measurement of the quark spin distributions of the nucleon at HERMES

Tallini, Hugh Arthur McLaren January 1998 (has links)
No description available.
138

Filosofická a psychologická problematika svobodné vůle. Svobodná vůle a odpovědnost / Philosophical and Psychological Aspects of Free Will. The Free Will and Responsibility

Stanková, Eva January 2013 (has links)
The question of free will, determinants of free action and responsibility is one of the most thrilling questions of the mankind. Moreover, the free will problem is closely connected to regulation and hindsight judgement of man behaviour so the law is concerned with the problem as well. However, a legal concept of free will is missing in the Czech law or legal theory. The author is therefore concerned with the fact that there is no satisfactory legal definition of free will even though legal responsibility is impliedly based on free action and free will. The Czech law defines just the freedom of action in negative terms, i.e. as an action of will free from circumstances limiting or precluding legal responsibility. The aim of the thesis is to summarize knowledge of social psychology regarding free will and assess whether the Czech law does impose the right standard of freedom of will in comparison to scientific experiments and findings. Furthermore, there are philosophical theories of free will introduced in the thesis and consequently these theories are questioned and examined for the purpose of defining legal concept of free will. At the end of the psychological part of the thesis one comes to the conclusion that the social determinants such as peer pressure, conformity and obedience to authority...
139

Towards an Understanding of the Gas Diffusion Layer in Polymer Electrolyte Membrane Fuel Cells

Morgan, Jason 12 December 2016 (has links)
The gas diffusion layer (GDL) is one of the key components in a polymer electrolyte membrane (PEM) fuel cell. It performs several functions including the transport of reactant gases and product water to and from the catalyst layer, conduction of both electrons and heat produced in the catalyst layer, as well as mechanical support for the membrane. The overarching goal of this work is to thoroughly examine the GDL structure and properties for use in PEM fuel cells, and more specifically, to determine how to characterize the GDL experimentally ex-situ, to understand its performance in-situ, and to relate theory to performance through controlled experimentation. Thus, the impact of readily measured effective water vapor diffusivity on the performance of the GDL is investigated and shown to correlate to the wet limiting current density, as a surrogate of the oxygen diffusivity to which it is more directly related. The influence of microporous layer (MPL) design and construction on the fuel cell performance is studied and recommendations are made for optimal MPL designs for different operating conditions. A method for modifying the PTFE (Teflon) distribution within the GDL is proposed and the impact of distribution of PTFE in the GDL on fuel cell performance is studied. A method for characterizing the surface roughness of the GDL is developed and the impact of surface roughness on various ex-situ GDL properties is investigated. Finally, a detailed analysis of the physical structure and permeability of the GDL is provided and a theoretical model is proposed to predict both dry and wet gas flow within a GDL based on mercury intrusion porosimetry and porometry data. It is hoped that this work will contribute to an improved understanding of the functioning and structure of the GDL and hence advance PEM fuel cell technology.
140

Qualidade física de solos com horizonte antrópico (Terra Preta de Índio) na Amazônia Central / Soil physical quality of anthropics horizons (Amazonian Dark Earth) in Central Amazon

Neves Junior, Afrânio Ferreira 06 June 2008 (has links)
As Terras Pretas de Índio (TPI) apresentam por definição o horizonte A antrópico, de cor escura, com presença de artefatos líticos e/ou cerâmicos oriundos do processo de ocupação humana na Amazônia. As áreas que ocorrem se diferenciam dos solos adjacentes por exibirem e manterem condições químicas do solo adequadas ao crescimento de plantas, mesmo após vários anos de cultivo. Essa pesquisa testa a hipótese que de que as TPI exibem condições físicas do solo adequadas ao crescimento de plantas e, mais adequadas que às encontradas nos solos adjacentes. O objetivo deste estudo foi avaliar as propriedades físicas dos horizontes antrópicos de duas TPI relacionando-as com as propriedades estruturais do solo que podem limitar o crescimento de plantas. Para a realização deste estudo foram amostradas duas áreas com horizonte A antrópico (TPI) e amostras do solo adjacente. A primeira área está localizada na estação experimental da Embrapa Amazônia Ocidental (Campo Experimental do Caldeirão) no município de Iranduba, Estado do Amazonas. O solo adjacente foi classificado como Argissolo Amarelo Tb Distrófico. A segunda área está localizada em uma pequena propriedade agrícola no município de Manacapuru, Estado do Amazonas. O solo adjacente foi classificado como Latossolo Amarelo Tb Distrófico. Para a caracterização das propriedades físicas do solo, coletaram-se 120 amostras de solo indeformadas na profundidade entre 0-0,05 m e oito amostras de solo com o formato de blocos (7,0 x 15 x 22 cm). As amostras coletadas foram utilizadas para determinar a curva de retenção da água no solo, a condutividade hidráulica saturada, a curva de resistência do solo à penetração, a densidade do solo, densidade de partículas, a porosidade total do solo, a estabilidade e a resistência tênsil de agregados e a friabilidade do solo. Além das propriedades físicas, o Intervalo Hídrico Ótimo (IHO) e o índice \"S\" foram utilizados como indicadores da qualidade física do solo. A hipótese da pesquisa foi parcialmente comprovada. Os índices de qualidade do solo constataram que as Terras Pretas de Índio apresentam condições físicas do solo adequadas ao crescimento de plantas, entretanto, as TPI não apresentam propriedades físicas mais adequadas ao crescimento de plantas que os horizontes superficiais adjacentes. / Amazonian Dark Earth (ADE) presents an Anthropic A horizon, with dark color and presence of lithic and ceramics sherds. Those topsoil characteristics resulted from old Indian settlements from the pre-Columbian time in the Amazon Basin. ADE shows differences from the surrounding soils by its very good soil chemical characteristics and that are still in the most sites very fertile and productive after long time of cultivation. In this study we tested the hypothesis that ADE presents good soil physical conditions to plant growth, and more appropriate than the surrounding soil. The objective of this study was to evaluate physical properties of Anthropic horizons of two sites with ADE. The soil physical properties were discussed concerning the potencial impacts on plant growth. The Anthropic horizons from two ADE sites were sampled and also the A horizon from the surrounding soil. The ADE sites sampled were located in the Amazonas State in Brazil, one at the Experimental Research Station of Embrapa Amazônia Ocidental (Campo Experimental do Caldeirão) - Iranduba, the surrounding soil was an Dystric Yellow Acrisol. The another site was located near the city of Manacapuru - AM in a private farm. The adjacent soil in this area was classified as Dystric Yellow Ferralsol. At the depth of 0-0,05 m, 120 soil cores were collected along with eight soil box (7,0 x 15 x 22 cm). At the laboratory, soil samples were analyzed to determine: soil water retention curve, saturated hydraulic conductivity, penetration resistance curve, bulk density, particle density, total porosity, aggregate stability, tensile strength and friability. The Least Limiting Water Range (LLWR) and S indexes were used as soil physical quality indicators. The hypothesis was partially proven. The soil quality indexes indicated that ADE presented appropriate soil physical conditions for plant growth; however, the ADE had no better soil physical quality than the surrounding soil.

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