This thesis investigates the small time asymptotics of solutions of stochastic equations in infinite dimensions. In this abstract H denotes a separable Hilbert space, A denotes a linear operator on H generating a strongly continuous semigroup and (W(t))t???0 denotes a separable Hilbert space-valued Wiener process. In chapter 2 we consider the mild solution (Xx(t))t???[0,1] of a stochastic initial value problem dX = AX dt + dW t ??? (0, 1] X(0) = x ??? H , where the equation has an invariant measure ??. Under some conditions L(Xx(t)) has a density k(t, x, ??) with respect to ?? and we can find the limit limt???0 t ln k(t, x, y). For infinite dimensional H this limit only provides the lower bound of a large deviation principle (LDP) for the family of continuous trajectory-valued random variables { t ??? [0, 1] ??? Xx(??t) : ?? ??? (0, 1]}. In each of chapters 3, 4 and 5 we find an LDP which describes the small time asymptotics of the continuous trajectories of the solution of a stochastic initial value problem. A crucial role is played by the LDP associated with the Gaussian trajectory-valued random variable of the noise. Chapter 3 considers the initial value problem dX(t) = (AX(t) + F(t,X(t))) dt + G(X(t)) dW(t) t ??? (0, 1] X(0) = x ??? H, where drift function F(t, ??) is Lipschitz continuous on H uniformly in t ??? [0, 1] and diffusion function G is Lipschitz continuous, taking values that are Hilbert-Schmidt operators. Chapter 4 considers an equation with dissipative drift function F defined on a separable Banach space continuously embedded in H; the solution has continuous trajectories in the Banach space. Chapter 5 considers a linear initial value problem with fractional Brownian motion noise. In chapter 6 we return to equations with Wiener process noise and find a lower bound for liminft???0 t ln P{X(0) ??? B,X(t) ??? C} for arbitrary L(X(0)) and Borel subsets B and C of H. We also obtain an upper bound for limsupt???0 t ln P{X(0) ??? B,X(t) ??? C} when the equation has an invariant measure ??, L(X(0)) is absolutely continuous with respect to ?? and the transition semigroup is holomorphic.

Thesis (Ph. D.)--University of Cambridge, 1995. / Cover title. "April 1996." Includes bibliographical references.

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In order to obtain an improved understanding of behaviour at work, employees should be studied from physical, psychological, and spiritual dimensions. Although the physical and psychological dimensions of individuals at work have been studied extensively, the spiritual dimension has been neglected for many years. The objective of the present research was to determine the relationship between spirituality and a positive work-related attitude, i.e. job satisfaction. A cross-sectional study was conducted with a sample of 600 white collar workers chosen from two organisations in different industries in South Africa. Personal spirituality, organisational spirituality, job satisfaction, and perceptions were measured. The data was analysed by means of a Principal Factor Analysis, Analysis of Variance (ANOVA), Item Analysis, Correlation Analysis, and Regression Analysis. Some instruments used in the study were revalidated. The primary result of this research indicated a positive relationship between organisational spirituality and job satisfaction. In addition, weak negative relationships were found between personal spirituality and job satisfaction, as well as personal spirituality and organisational spirituality. Personal spirituality showed statistically significant associations with biographical-type variables such as gender, ethnical grouping, and strength of religious conviction. The association between personal spirituality and strength of religious conviction significantly differed between the private hospital and educational organisation. Organisational spirituality showed a statistically significant association with age. The association between organisational spirituality and gender significantly differed between the private hospital and educational organisation. The two organisations were also found to differ in terms of organisational spirituality, with the educational organisation measuring higher on organisational spirituality than did the private hospital. Job satisfaction and perceptions did not show statistically significant associations with any of the biographical-type variables. Furthermore, it was determined that the respondents perceive personal spirituality and job satisfaction to be related. These findings deepened the understanding of personal spirituality, organisational spirituality, and job satisfaction. It brought new insight into the significant role which spirituality plays in the context of the workplace. To survive in the 21st century, organisations need to be spiritually-based. This in turn will lead to workers being satisfied with their entire work experience. / Thesis (PhD (Organizational Behaviour))--University of Pretoria, 2008. / Human Resource Management / PhD / unrestricted

With the rapid and exponential growth of Internet use worldwide, online learning has become one of the most widely used learning paradigms in the education environment. Yet despite the rapidly increasing cultural diversity of online learners, few studies have investigated the effectiveness of cross-cultural Online Learning Systems (OLS) using a suitable measurement to answer the question, "Do culturally different learners perceive OLS effectiveness differently?" In this study, Hofstede's theory on cultural dimensions and Levy's Learners' Value Index of Satisfaction (LeVIS) framework are applied as a foundation for studying how culturally different learners perceive OLS effectiveness. The aim of this comparative study was to gain a better understanding of OLS effectiveness in a non-western culture by comparing cultural dimensions and learners' perceived effectiveness of OLS (across the four pillars: technology/support, course, professor, & learner) among American and Malaysian learners. Learners from American and Malaysian universities were surveyed and a factorial analysis of variance (factorial ANOVA) was used to determine any significant differences among participants regarding perceived OLS effectiveness across the four pillars of OLS based upon Hofstede's cultural dimensions. Results indicated significant differences in perceived OLS effectiveness between American and Malaysian learners in the course and professor pillars based on Hofstede's five cultural dimensions. However, the technology/support and learner pillars showed no significant differences between American and Malaysian learners' perceived OLS effectiveness. The main contribution of this study is its findings regarding the effect of culture on perceived OLS effectiveness. This study examined American and Malaysian learners' perceived effectiveness of the technology/support, course, professor, and learner pillars of OLS based on Hofstede's five cultural dimensions. Based upon analysis of the survey results, it was determined that American learners perceived a slightly higher OLS effectiveness in terms of the course and professor pillars than Malaysian learners. In other words, the survey indicated that the cultural dimensions distinguishing American and Malaysian learners influenced those two groups' perceived effectiveness of the course and professor pillars of the OLS. Another contribution of this study is its recommendation, based upon the survey results, that Malaysian OLS course designers develop and implement course content and activities in the online learning environment to alleviate the apparent conflict between current online learning and Malaysian cultural characteristics. It is further recommended that Malaysian professors using OLS also strive to develop an instructional method more suitable to the cultural norms of Malaysian society. On a general level, it is hoped that this study will also contribute to a better awareness and understanding of the important and unresolved issues surrounding cultural attributes and learners' perceived OLS effectiveness. Based on this study, recommendations were made for future research in order to broaden, reenforce or adjust its findings. These included, 1) replicating this study in another setting, such as in the collaborative environment of international organizations; 2) including additional independent variables, such as academic major, enrollment status (full or part time), first language, graduate student status, and grade point average; 3) replicating the current study using a larger sample with multiple locations and cultures, and 4) replicating this study at a future date to reflect potential changes in culture, technology, and OLS design.

This study was instigated by the lack of human dimensions research undertaken in New Zealand, and seeks to investigate the knowledge and values New Zealanders hold about New Zealand wildlife within three distinct groups of the New Zealand public. These groups were the Royal Forest and Bird Society of New Zealand Inc, the New Zealand Ecological Society (Inc.), and the New Zealand Deerstalkers Association. A questionnaire administered via Association list-serv's was utilised and a total of 52 questionnaires were completed by members of the three stakeholder groups. These were then analysed to investigate the values and knowledge New Zealanders hold toward wildlife in New Zealand. The findings of this study suggest that New Zealander's hold strong utilitarian and negativistic values toward wildlife while the humanistic, moralistic, and naturalistic values were expressed by the majority of respondents. This result could be due to the high level of respondents who were from the New Zealand Deerstalkers Association. Conversely, whiled the data suggests that New Zealander's hold the ecologistic/scientific value only weakly, overall they have a high level of factual knowledge about wildlife. Because of this, it may be suggested that wildlife managers should generate education programmes that specifically address the negativistic value by making them imaginative and interesting. Demographic factors were found to be influential in the ways in which New Zealander's value wildlife and the knowledge they hold although these were not as significant as indicated by studies undertaken in other countries. The lowest levels of knowledge were shown by respondents who were over 60 years of age; and higher income levels corresponded with the negativistic value being held more highly. Several areas of this study showed transgressions from other studies undertaken overseas. Unlike other studies, which suggested that females hold the naturalistic value more strongly than males, this study showed that both males and females held the naturalistic value only weakly. This indicates that findings from studies conducted overseas may not be transferable to the New Zealand situation and therefore, for New Zealand managers to effectively incorporate human dimensions information in decision-making processes, human dimensions research must be undertaken in the New Zealand context. Furthermore, wildlife managers should not make assumptions based on other studies and communities as these can lead to ineffective communication and implementation of wildlife management policies and education programmes.

La thèse contient un premier chapitre avec des préliminaires sur les langages bidimensionnels, sur les résultats principaux et sur les différentes caractérisations des langages reconnaissables par systèmes de pavages qui jouent un rôle central dans la thèse. Ensuite, nous décrivons la structure algébrique des familles des langages locaux. Nous prouvons que cette structure est un treillis par rapport à l'inclusion et nous étudions les propriétés de ce treillis. Par ailleurs, nous traitons des problèmes informatiques de décidabilité et nous donnons la position, dans la hiérarchie arithmétique, des problèmes classiques sur des langages de mots appliquées aux langages bidimensionnelles. Dans la thèse, après quelques définitions de base sur les polyominos, nous traitons la reconnaissabilité de plusieurs classes des polyominos par des langages reconnaissables par systèmes de pavages. En particulier, nous donnons les systèmes de pavages pour des langages représentant les classes des polyominos convexes, h-convexes ou parallélogrammes. Ensuite, nous étudions la reconnaissabilité des polyominos L-convexes. En conclusion, la dernière partie de la thèse est consacrée à l'application des langages reconnaissables par systèmes de pavages au calcul d'ADN. Nous donnons l'idée de la construction avec de l'ADN de quelques classes des polyominos (par exemple la classe des polyominos parallélogrammes) obtenues à travers la famille des langages reconnaissables par systèmes de pavages.

<p>It is an intriguing possibility that our world may consist of more than three spatial dimensions, compactified on such a small scale that they so far have escaped detection. In this thesis, a particular realization of this idea -- the scenario of so-called 'universal extra dimensions' (UED) -- is studied in some detail, with a focus on cosmological consequences and appplications.</p><p>The first part investigates whether the size of homogeneous extra dimensions can be stabilized on cosmological time scales. This is necessary in order not to violate the stringent observational bounds on a possible variation of the fundamental constants of nature.</p><p>An important aspect of the UED model is that it can provide a natural explanation for the mysterious dark matter, which contributes nearly thirty times as much as luminous matter like stars, galaxies etc. to the total energy content of the universe. In the second part of this thesis, the observational prospects for such a dark matter candidate are examined. In particular, it is shown how dark matter annihilations taking place in the Milky Way could give rise to exotic contributions to the cosmic ray spectrum in photons and antiprotons, leading to distinct experimental signatures to look for.</p><p>This includes a comparison with similar effects from other dark matter candidates, most notably the neutralino, which appears in supersymmetric extensions of the standard model of particle physics.</p>

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