In this thesis we present work done in an analysis of models of brane induced gravity. These are higher dimensional generalizations of Einstein's General relativity where our universe is considered as a brane in a higher dimensional bulk and where the gravitational dynamics on the brane is enhanced. This provides a modification of gravity on the brane as compared to ordinary general relativity, primarily at very large distances. These models are therefore very interesting for adressing the cosmological constant problem. Even though the basic setup is natural to consider from the perspective of effective field theory and also follow from certain string theoretical considerations, the models have been plagued by inconsistencies in the form of unstable modes. In particular, a ghostlike and tachyonic scalar mode appears already at the linear level in a perturbative treatment. In order to gain a deeper insight into the nature of these consistency problems we have revisited the models, performing a more extensive analysis of the generic models than has previously been done. We have worked entirely in a gauge invariant formalism in order not to be obscured by gauge issues. We have also incorporated an effective thickness of the brane in our analysis and performed an explicit analysis of the effect of contributions from the extrinsic geometry. Although our analysis has been carried out at the linear level in a perturbative treatment we are able to get a deeper understanding of the unstable mode and illuminate some of the difficulties of these models that would likely persist even in a full nonlinear analysis.

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. 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. 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. 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.

Cette thèse établit, et étudie, un lien entre l'homologie de Khovanov et la topologie des revêtements ramifiés doubles. Nous y introduisons certaines propriétés de stabilité en homologie de Khovanov, dont nous dérivons par la suite des obstructions à l'existence de certaines chirurgies exceptionnelles sur les noeuds admettant une involution appropriée. Ce comportement, analogue à celui de l'homologie de Heegaard-Floer sous chirurgie, renforce ainsi le lien existant (dû à Ozsváth et Szabó) entre homologie de Khovanov, et homologie d'Heegaard-Floer des revêtements ramifiés doubles. Dans l'optique de poursuivre et d'exploiter plus avant cette relation, les méthodes développées dans ce travail sont appliquées à l'étude des L-espaces, et à déterminer, en premier lieu, si l'homologie de Khovanov fournit un invariant des revêtements ramifiés doubles, et en deuxième lieu, si l'homologie de Khovanov permet de détecter le noeud trivial. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Homologie de Khovanov, Homologie de Heegaard-Floer, Chirurgies de Dehn, Involutions, Variétés de dimension trois, Revêtements ramifiés doubles.

In the midst of stiff and fierce competition and increased number of grocery retail outlets providing a variety of products, customers have become accustomed to patronizing multiple outlets. Retailers have recognized this trend and are of the view that customer satisfaction plays a role in the success of business strategies. Therefore it has become important for grocery retail stores to try and manage customer satisfaction. This paper was thus developed to investigate the satisfaction levels of customers in supermarkets. Data was collected from three supermarkets in Visby, Gotland. The study examined the importance of overall dimensions and specific elements of customer satisfaction towards the measurement of satisfaction levels. In addition, comparative analysis was conducted between the three relative grocery stores. Customer satisfaction levels were measured. The highest percentage of customers of the whole sample belonged to medium level of satisfaction. The statistical result concluded that customers of ICA Nära and customers of ICA were higher satisfied than those of Coop Forum. The results showed that customers felt satisfied with Location, Staff courtesy and Reliability of supermarkets as the top aspects that drive satisfaction while additional services were ranked lowest. Due to these results, the impact of these attributes on Customer satisfaction must not be underestimated.

With the millions of students currently enrolled in higher education, a substantial opportunity arises for college personnel to impact the health and wellness of our future U.S. adult population. Most health scholars agree that wellness is a multidimensional construct. Despite disagreement regarding the optimal number of dimensions - ranging from three to twelve - there is a general consensus around the following: (1) physical, (2) social, (3) spiritual, (4) intellectual, (5) emotional, and (6) occupational. With regard to these six dimensions of wellness, the purpose of this study was to conduct a naturalistic inquiry among graduating health education majors to evaluate which particular dimension of wellness was most influenced or impacted, by their college life experience. Participants were recruited via email and in-class-visits. Of the 173 students who were eligible to participate in this study at the time of recruitment, 58 indicated interest and a final sample size of 30 students were interviewed. When determining which specific dimension of wellness was most impacted or influenced by the college life experience, two narratives of an unplanned pregnancy and alcoholism immediately came to mind. However, when trying to compile all 30 narratives to identify which dimension was most impacted, collectively, I concluded that all dimensions were impacted, and, due to the dimensions' interconnectedness, no one particular dimension could be singled out as most impacted. The six dimensions of wellness interact continually and synergistically. For example, the need for stress management and stress reduction is linked mostly obviously with emotional wellness; however, should one practice yoga for stress relief, he/she is impacting their physical, social, and spiritual health as well. Segmenting students' narratives about their college life experiences into discrete domains represented a challenge - one that reflects how activities that support wellness cannot easily be segmented into discrete domains, either.

<p>Culture plays a key role in international business. This work-based thesis undertakes a case-study research of an information management software introduction process from Sweden to China. To design interview questions, the author used Prof. Hofstede’s cultural dimensions as the base theory and reviewed a number of literatures which apply this theory in the IT area. After interviews with both Swedish and Chinese sites, the results were analyzed with the theoretical data to examine how cultural differences influence people in a software introduction process. The author also applied software culturalization from Marble and Lu. Compared to the author’s own experiences and interview data, a recommendation list is stated as a guide of how to succeed in software introduction under different cultural backgrounds.</p>

Reproduction de : Thèse de docteur-ingénieur : informatique : Grenoble, INPG : 1984. / Titre provenant de l'écran-titre. Bibliogr. p. 122-137.

Habilitation à diriger des recherches : Informatique : Rennes 1 : 1999. / Bibliogr. p.109-136.

In this lecture we introduce a new transfinite dimension function for metric spaces which utilizes Henderson's topological D-dimension and ascribes to any metric space either an ordinal number or the symbol Ω. The construction of our function is motivated by that of Urbański's transfinite Hausdorff dimension, tHD. Henderson's dimension is a topological invariant, however, like Hausdorff dimension and tHD the function presented will be invariant under bi-Lipschitz continuous maps and generally not under homeomorphisms. We present some original results on D-dimension and build the general theory for the D-variant of transfinite Hausdorff dimension, \mathrm{t}_D\mathrm{HD}. In particular, we will show for any ordinal number α, existence of a metrizable space which has \mathrm{t}_D\mathrm{HD} greater than or equal to α and less than or equal to \omega_\tau, where τ is the least ordinal which satisfies α < \omega_\tau.

This thesis considers various aspects of general relativity in more than four spacetime dimensions. Firstly, I review the generalization to higher dimensions of the algebraic classification of the Weyl tensor and the Newman-Penrose formalism. In four dimensions, these techniques have proved useful for studying many aspects of general relativity, and it is hoped that their higher dimensional generalizations will prove equally useful in the future. Unfortunately, many calculations using the Newman-Penrose formalism can be unnecessarily complicated. To address this, I describe new work introducing a higher-dimensional generalization of the so-called Geroch-Held-Penrose formalism, which allows for a partially covariant reformulation of general relativity. This approach provides great simplifications for many calculations involving spacetimes which admit one or two preferred null directions. The next chapter describes the proof of an important result regarding algebraic classification in higher dimensions. The classification is based upon the existence of a particular null direction that is aligned with the Weyl tensor of the geometry in some appropriate sense. In four dimensions, it is known that a null vector field is such a multiple Weyl aligned null direction (WAND) if and only if it is tangent to a shearfree null geodesic congruence. This is not the case in higher dimensions. However, I have formulated and proved a partial generalization of the result to arbitrary dimension, namely that a spacetime admits a multiple WAND if and only if it admits a geodesic multiple WAND.Moving onto more physical applications, I describe how the formalism that we have developed can be applied to study certain aspects of the stability of extremal black holes in arbitrary dimension. The final chapter of the thesis has a rather different flavour. I give a detailed analysis of the properties of a particular solution to the Einstein equations in five dimensions: the Pomeransky-Sen'kov doubly spinning black ring. I study geodesic motion around this black ring and demonstrate the separability of the Hamilton-Jacobi equation for null, zero energy geodesics. I show that this unexpected separability can be understood in terms of a symmetry described by a conformal Killing tensor on a four dimensional spacetime obtained by a Kaluza-Klein reduction of the original black ring spacetime.