Les polaritons de microcavité sont des états hybrides lumière-matière à caractère bosonique.Dans les dernières décennies, un grand intérêt a été accordé à leur phase de condensation de Bose-Einstein.Nous avons développé dans ce travail des outils théoriques et numériques pour comprendre et interpréter la dynamique spatiale et temporelle de la formation des condensats de polaritons.Nous avons proposé une approche numérique pour la résolution complète des équations couplées du modèle Gross-Pitaevskii généralisé à deux dimensions en coordonnées cartésiennes.Nous avons cherché à comprendre les aspects du seuil de condensation sous différentes configurations spatiales et temporelles d'excitation optique non résonante.Nous avons en particulier proposé une nouvelle approche pour définir le seuil.Enfin, pour une condensation sous exciation focalisée, dans une microcavité ZnO, nous avons pu accéder à, et comprendre, quelques propriétés vues dans les expériences. / Microcavity polaritons are hybrid light-material states of a bosonic nature.In the last decades, an enormous interest has been paid to their Bose-Einstein condensation phase.We develop, in this work the theoretical and numerical tools to understand and interpret the spatial and temporal dynamics of the formation of condensates of polaritons.We propose a numerical approach for the comprehensive resolution of the generalized Gross-Pitaevskii model in two-dimensions in Cartesian coordinates.We sought to understand the aspects of the condensation threshold under different spatial and temporal configurations of non-resonant optical excitation.In particular, we propose a new approach to define the threshold.Finally, for a condensation under a focal exciation in a ZnO microcavity, we were able to access, and understand, some of the experimentally observed properties.

The decline in agricultural productivity in Nigeria is linked to a host of factors ranging from unsustainable growth policies, inadequate funding and infrastructures, low levels of value added through processing, low commodity prices, unstable markets, poor extension services and low rates of literacy. It is now well recognised that there is a need to diversify Nigerian agriculture as well as improving production performances. This study investigates the potential of cassava root tuber (CRT), as a means to promote agricultural growth. It assesses cassava production, profitability, efficiency, marketing structures and channels, constraints in production, the potential to add value by processing cassava into gari (a fermented, roasted, and dried granule) and its marketing at the farm level. These were supplemented by a critical review of policies and programmes, including trend analysis of cultivated area, production, yield and prices of major crops including cassava at the national level covering the period 1970–2009. The study surveyed 315 cassava producers (including 278 gari processors), 105 marketers involved in cassava marketing and 30 stakeholders from three regions in the Delta State, Nigeria. Descriptive statistics are used to analyse the socio-economic characteristics of the sample. In addition, profitability of CRT and gari and their marketing were assessed by benefit-cost analysis. Furthermore, productivity and efficiency of CRT and gari and their determinants were analysed using non-parametric DEA followed by Tobit regressions. Results indicate that cassava production and processing is profitable in all regions and for all farm size categories. The BCR is estimated at 2.83 and 1.22 for CRT and gari, respectively. However, the yield level of CRT and gari is very low, estimated at 7.7 t/ha and 4.7 t/ha, respectively. Also, efficiency levels are very low and vary by farm size as well as regions, with large scale producers relatively more efficient. Marketing of cassava in any form is profitable and efficient (Marketing Efficiency>1 in all cases) and profitability varies widely across regions. Provision of water was identified as the main constraint in processing, followed by shortage of electricity and poor marketing infrastructure. The review of past policies and trend analysis revealed inconsistent policies and fluctuations in agricultural productivity, but also showed increases in total production mainly driven by expansion of the area cultivated during later years, for cassava in particular. The policy implications include: (a) increased provision of modern technologies, use of improved varieties and modern technology; (b) land reform policies to consolidate farm size; (c) investment in elements of marketing infrastructure; and (d) improvements in extension services. Despite inconsistencies in policies, cassava stood out as a robust and resistant crop which provides confidence that targeted investment in the cassava sector will contribute to development of Nigerian agriculture.

<p>Private investment in Botswana as well as a ratio to Gross Domestic Product has been falling in some periods of 1976-2003. Viewed against the background of growing evidence of a link between investment and economic growth, an inconsistent and downward trend in Botswana's private investment is a matter of concern. Several studies in developing countries emphasize the importance of macroeconomic policy in explaining variations in investment, an in particular, identify the microeconomic determinants of private investment to include interest rates, output growth, public investment, bank credit to the private sector, inflation, real exchange rate, and the level of trade. This study evaluated the macroeconomic determinants of private investment in Botswana by means of a regression analysis based on the co-integration and Error Correction Model of Engle and Granger (1987).</p>

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<p>This thesis aims at explaining why the UK residential electricity (retail) market enjoys high gross margins in comparison to Vattenfall’s markets in for example Sweden. Gross margin is the difference between selling price and purchase costs, in this case the wholesale electricity price. The wholesale market essentially affects all retailers in the same way and can be analysed separately, therefore it is of great interest to analyse how there can be such a wide gap between the end-user electricity price and the wholesale price. Since the UK electricity market is seen as a forerunner to other markets, being an early adopter of liberalisation of a previously state-controlled industry and seen as the most competitive market in the world, it seems a bit odd that retail electricity prices are not pushed down to a margin cost level as is expected on a perfectly competitive market.</p><p>The report concludes that there are substantially higher gross margins on the UK market and then goes on to determine which the underlying drivers to this situation are. There are two underlying socio-cultural factors that have driven the development of the market. First it is the history of deregulation that brought lower end-user prices but also bad service experiences. Secondly, the UK public has a market-friendly mentality and acceptance to how the industry works. The result is that focus has moved away from price and there is little public worry about the market being too concentrated. Two more underlying drivers are related to the properties of the market: the linkage between gas and electricity that has lessened the impact of the electricity price and the UK trading system that makes it hard for new retailers to enter the market and put a pressure downwards on prices and gross margins.</p><p>These four underlying drivers have created a market situation where price has not been perceived as the only value component of electricity and where the focus on price and gross margins has been overshadowed by other issues in the public debate. The troublesome history have produced a ‘demand for brand’ that signals safety, which has helped building substantial barriers of entry and survival for non-incumbents retailers. Together with a highly consolidated market structure, a handful of large retailers are enabled to dominate the market and push up prices with little fear of retribution from competitors or society.</p> / The attachment F is data corrections of figures 1.7 and 1.8.

Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 109-116).

It is a research of the move trajectory of the ciliates while feeding the food, in order to estimate, differentiate from the movement behavior under different environments. First, discuss the differently distinguish with the single indicator. Second, discuss with integrate four kinds of indicator whether can distinguish differently. Finally, combine the indicator data and through different analysis technology look out the features of movement behavior, expect to be able to look out suitable information and knowledge from the indicator data. After deal with analytical technology, the result of decision tree is most suitable for predicted and have credibilities. If according to energy of biological, the analysis result is similar to optimal foraging theory. And learn from result under different condition, the movement behavior of the ciliates similar to the optimal foraging theory. In the matter of the result of analysis technology, data of the density of low food similar to data of the density of extremely high food. Besides, data of medium food and high food are analogous. The rule of decision tree can distinguish the density of different food, and can offer follow-up study to distinguish the environmental conditions. Those models are evaluated by predicting accuracies, and rules extracted from decision tree models are also of great help to prediction as well.

As corporate social responsibility (CSR) reporting becomes an increasingly adopted practice, the question concerning its utility remains. Many organizations including the Carbon Disclosure Project (CDP) and Global Reporting Initiative encourage firms to report because of purported benefits to revenue generation and cost control. This study investigates whether such boons of CSR reporting exist in the manufacturing industry by building a regression model that analyzes the relationship between gross profit margins and response to CDP questionnaires. While the results of the study are inconclusive, they hint at a positive relationship between CSR reporting and profitability. Further research with a larger data set and broader measure of CSR reporting is required to definitively state whether any significant relationship between the two variables exist.

This thesis aims at explaining why the UK residential electricity (retail) market enjoys high gross margins in comparison to Vattenfall’s markets in for example Sweden. Gross margin is the difference between selling price and purchase costs, in this case the wholesale electricity price. The wholesale market essentially affects all retailers in the same way and can be analysed separately, therefore it is of great interest to analyse how there can be such a wide gap between the end-user electricity price and the wholesale price. Since the UK electricity market is seen as a forerunner to other markets, being an early adopter of liberalisation of a previously state-controlled industry and seen as the most competitive market in the world, it seems a bit odd that retail electricity prices are not pushed down to a margin cost level as is expected on a perfectly competitive market. The report concludes that there are substantially higher gross margins on the UK market and then goes on to determine which the underlying drivers to this situation are. There are two underlying socio-cultural factors that have driven the development of the market. First it is the history of deregulation that brought lower end-user prices but also bad service experiences. Secondly, the UK public has a market-friendly mentality and acceptance to how the industry works. The result is that focus has moved away from price and there is little public worry about the market being too concentrated. Two more underlying drivers are related to the properties of the market: the linkage between gas and electricity that has lessened the impact of the electricity price and the UK trading system that makes it hard for new retailers to enter the market and put a pressure downwards on prices and gross margins. These four underlying drivers have created a market situation where price has not been perceived as the only value component of electricity and where the focus on price and gross margins has been overshadowed by other issues in the public debate. The troublesome history have produced a ‘demand for brand’ that signals safety, which has helped building substantial barriers of entry and survival for non-incumbents retailers. Together with a highly consolidated market structure, a handful of large retailers are enabled to dominate the market and push up prices with little fear of retribution from competitors or society. / The attachment F is data corrections of figures 1.7 and 1.8.

The fact that saving is one of the main factors to economic growth is unquestionable. Accumulated saving can be consider as the sources of capital stock to which play a crucial role in creating investment, production, and employment. And all these activities eventually enhance the economic growth. Therefore the main objective of this paper, ―The relationship between domestic saving and economic growth and convergence hypothesis: case study of Thailand‖, was to investigate the causality relationship between the domestic saving and economic growth of Thailand. This paper will analyze whether the direction of causality go from domestic saving to economic growth, or vice versa. Granger causality test were conducted by using time series annual data from 1960 to 2010, and the empirical result suggests that the direct of causality go from economic growth to domestic saving only. Aiming to grow its economy, Thailand had had development plans which used both saving and direct investment to stimulate economy. This paper examine whether the convergence hypothesis does hold in Thailand. This part would check whether or not Thailand is in the process of convergence, catching up, lagging behind, loose catching up, loose lagging behind or divergence over time compared with other developed countries. This test was conducted in pairwise between Thailand-Singapore, Thailand-United States, Thailand-United Kingdom, deployed data from 1970 to 2010, and the Augmented Dickey–Fuller (ADF) Test. The regression results demonstrate that convergence hypothesis does not hold in Thailand. Finally, the result of Granger Causality report that economic growth rate does matter lead to growth rate of domestic savings in Thailand only. Thus, in order to learn the effect of gross domestic saving per capita growth rate can help narrow the different of GDP between two countries concerned, this paper will examine the correlation of two variables, deployed the OSL methods to investigate the correlation between gross domestic saving growth rate and the different of GDP per capita between Thailand and Singapore. This test also examine whether saving does help support convergence hypothesis for Thailand or not. The test results shows that domestic saving growth rate does not help narrowing the range of different of income of Thailand and Singapore which mean that domestic saving growth rate does not support the convergence hypothesis in Thailand.