Neste trabalho é elaborada uma solução analítica do campo de temperatura em um material opaco, contendo dois cilindros subsuperficiais paralelos e acoplados, iluminado por um feixe de luz modulado. O método é baseado na expansão de ondas térmicas planas e cilíndricas em série de funções de Bessel e Hankel. Primeiramente, o trabalho mostra o modelo da propagação de ondas térmicas planas em um material homogêneo, infinito, opaco e termicamente isotrópico. Então, para um melhor entendimento da abordagem matemática, iniciamos com o modelo mais simples, que é um material contendo apenas um cilindro. Após, ampliamos o modelo colocando dois cilindros separados neste material, onde aparecem os efeitos de múltiplos espalhamentos. Em seguida, tratamos os modelos descritos em meios semi-infinitos, no qual levamos em consideração a condição adiabática na fronteira da amostra com o ar, ou seja, o meio não perde calor para o ambiente. Esta condição é representada pelo método das imagens. A heterogeneidade do meio é alcançada com a generalização do modelo para um meio com N cilindros separados. Finalmente, incluimos as modificações dos modelos prévios devido ao acoplamento de dois cilindros. Este modelo é geral, no sentido que não existem restrições com respeito aos diâmetros e posições dos cilindros dentro do material, nem com relação às propriedades térmicas dos cilindros e matriz. Além disso, serve para calcular a temperatura em qualquer ponto da amostra. As ondas térmicas levam informações sobre a estrutura interna e propriedades térmicas do material compósito que, na prática, podem ser obtidas através das medidas da temperatura na superfície da amostra através de técnicas fototérmicas. Com isto, somos capazes de caracterizar estruturalmente um material compósito reforçado por fibras. Também podemos caracterizá-los termicamente obtendo suas propriedades térmicas efetivas. Medidas experimentais com amostras calibradas usando a técnica de termografia infravermelho lock-in (radiometria fototérmica), com frequência fixa, confirmam a validade do modelo. Além disso, um estudo da distribuição de ondas térmicas em materiais contendo esferas também estão discutidos teoricamente aqui. / In this work we elaborate an analytical solution of the temperature field of an opaque material containing two overlapping and parallel subsurface cylinders, illuminated by a modulated light beam. The method is based on the expansion of plane and cylindrical thermal waves, in series of Bessel and Hankel functions. Firstly, the work shows the model of propagation of plane thermal waves in homogeneous, infinite, opaque and thermally isotropic materials. Then, for a clearer mathematical study, we initiate with a simpler method, which is a material containing only one cylinder. After that, we expanded the model by placing two separated cylinders inside of this material where the multiple scattering effects appeared. In the sequence we will treat the described model in semi-infinite materials, in which we take into consideration the adiabatic condition at the border of the sample with the air, that is, the material does not loose heat to the environment. This condition is represented through method of images. The heterogeneity of the medium is achieved with the generalization of the model for a medium with N separated cylinders. Finally, we include the modifications to the previous model due to the overlapping of these cylinders. This model is general, in the sense that there are no restrictions when considering the diameters and positions of the cylinders inside the material nor with respect to the thermal properties of the cylinders and matrix. Besides, it can be used to calculate the temperature at any point of the sample. The thermal waves carry informations about the composite materials internal structure and thermal properties that, in practice, can be obtained with the measurement of the temperature in the surface of the sample, through photothermal techniques. Considering this, we are able to structurally characterize a composite material of fibers. We are also capable of characterizings them thermally, obtaining their effective thermal properties. We have performed measurements on calibrated samples using lock-in infrared thermografy (photothermal radiometry) with a fixed frequency which confirms the validity of the model. Furthermore, a study of thermal waves distributions on materials containing spheres are also discussed theoretically here.

Chapter 1 Low-skilled Migration and Altruism: Population ageing has become a common concern among welfare states, including Canada and most of the OECD countries. Immigration has been identified as a solution to help sustain labour-force growth in industrialized countries, and as the factor most able to mitigate dire predictions of future fiscal imbalances. This chapter examines the impact of low-skilled immigration in a host country where households are altruists with a pay-as-you-go pension system to support the elderly. It demonstrates that low-skilled immigration does not harm the welfare of the domestic population. We use an overlapping-generations model similar to the work of Razin and Sadka (2000) but introduce paternalistic altruism into the life-cycle framework. Within this context of inter-generational altruism and pay-as-you-go pension systems, the initial negative fiscal impact of low-skilled migrants is compensated, thus, all income groups (high and low) and all age groups (young and old) benefit from migration. // Chapter 2 Growth and Sustainability: In light of the major environmental issues experienced by several countries in the last decades, several papers have advocated the rethinking of the role of governments in environmental preservation. This chapter develops an overlapping-generations model of environmental quality and production and investigates the potential role of governmental participation in the preservation of the quality of the environment so as to achieve both economic growth and environmental sustainability. The analysis suggests that long term economic growth and environment sustainability can be maintained with tax-funded environmental programs in a context of a negative production externality on the quality of the environment. // Chapter 3 The Incidence of Geography on Canada’s Services Trade: We estimate geographic barriers to export trade in nine service categories for Canada's provinces from 1997 to 2007 using the structural gravity model. Constructed Home, Domestic and Foreign Bias indexes capture the direct plus indirect effect of services trade costs on intra-provincial, inter-provincial and international trade relative to their frictionless benchmarks. Barriers to services international trade are huge relative to inter-provincial trade and large relative to goods international trade. A novel test confirms the fit of structural gravity with services trade data.

Chapter 1: Interregional Transfers through Public Pension in Canada- In this chapter, I build a regional computable general equilibrium model with an overlapping generations (OLG) structure of the Canadian economy to analyze population aging dynamics and public pensions. Canada is divided into three regions: Atlantic, Quebec and Rest of Canada (ROC). The impact of population aging is investigated on each of three regions' pension systems. The results confirm that as a result of aging all regions are affected negatively if they choose to have an independent pension system. Under a joint pension system most of the pressure of the provision of the pension system is on the ROC. Atlantic region benefits the most from a joint pension plan as the implicit funds ow from ROC to Atlantic region. Quebec benefits from having its own program, but the benefits disappear slowly in future years. Chapter 2: Age-Variable Rate of Time Preference in CGE-OLG Model- Contrary to the mainstream studies in the area of intertemporal optimization that assume a constant rate of time preference over individuals' life cycles, in this chapter I propose a new approach to measure the rate of time preference by assuming that the rate of time preference evolves by age. I construct an overlapping generations model (OLG) and calibrate rate of time preference. The age-variable rate of time preference would permit to capture many other elements that affect the life cycle profile of consumption as observed in the data. The results show that rate of time preference exhibits three phases and is different for young versus old. Chapter 3: Computing Demographic Change Simulation under Constant and Age-variable Rate of Time Preference - This chapter simulates the impact of an aging population on various macroeconomic variables and calculates the cohort welfare as well as social welfare. The outcomes from simulations are dependent on the choice of rate of time preference as well as the structure of the model. The results in this chapter provide a new approach to determining the impact of aging population. The choice of a realistic rate of time preference, which allows its variability by age, affects the cohort welfare noticeably.

Magíster en Economía Aplicada. Ingeniero Civil Industrial / Desarrollamos un modelo de equilibrio dinámico para el fenómeno de Overlapping , donde agentes neutros al riesgo transan un activo de forma continua en libros de órdenes reales mediante órdenes de tipo market y limit . Encontramos que los principales oferentes de órdenes limit se ven beneficiados tanto en la apertura como en el cierre del overlap . Antes del inicio, cargan el libro con órdenes limit lejos de los precios de bid y ask . Al cierre del overlap , obtienen los mejores términos transaccionales del día, alcanzando así su máximo bienestar. Por otro lado, los demandantes de órdenes tipo market tienen su bienestar mínimo durante los primeros minutos de overlap entre los libros de órdenes.

No description available.

Increasing evidence suggests that overlapping genes is a common phenomenon in eukaryotic genomes too and are not restricted to prokaryotes alone. Here we determined overlapping genes in a set of orthologous genes in the genomes of human, chimp, mouse, rat, and dog and contrasted the patterns of overlapping between two principal types of overlapping genes, the same-strand-overlapping genes and different-strand-overlapping genes. The two types of overlapping genes are compared with respect to their frequencies, overlap lengths, region of overlap, and conservation of overlap in five species. Our results suggest the following: different-strand-overlaps are more common, both types show different patterns with respect to overlap lengths and regions of overlap, different-strand-overlapping genes are more evolutionarily conserved, and 3'-UTR evolution plays an important role in transitions between non-overlapping genes and overlapping genes. The thesis also presents a review of related work in terms of history, origin, types, biological significance of overlapping genes, human diseases associated with them, and their comparison in prokaryotes and eukaryotes. / Master of Science

The main objective of this study is to analyze the effects cotton quality has on hedging and basis movements within the cotton market to help market participants minimize price risk. The effectiveness of using cotton futures in hedging price risk will be determined by calculating optimal hedge ratios by tenderable quality. Hedge ratios will be calculated using simple differences and error correction models (ECM) on overlapping price data, estimated under both generalized least squares (GLS) and maximum likelihood estimation (MLE). An empirical analysis shows that as cotton quality improves, the optimal hedge ratio decreases. ECMs estimated under GLS are found to be most efficient. It is also found that cotton classing data by quality has no significant effect on cotton basis. Farmers and merchandisers can take these results as a framework to better manage price and basis risk in the hedge and speculative scenarios.

Thesis (PhD (Electrical and Electronic Engineering))--University of Stellenbosch, 2009.

Multiculturalism, as a set of ideas and policies, is one of the normativeapproaches to the current situation of cultural diversity in multicultural cities.But how can the ideas of multiculturalism be translated into the reality of urbanform? The overall aim of this dissertation is to provide a theoretical andconceptual frame of reference for distilling and identifying the ideas ofmulticulturalism which can be translated into spatial form, and in this way, tohighlight the role urban form may play in addressing the situation of living‘together-in-difference’. In this study, the relation between the materiality ofurban form and the political framework of multiculturalism is at the core of thediscussion.In its exploration into multiculturalism, the thesis identifies theoretical lacunae inexplaining the spatial dimensions of multiculturalism. To be able to discussmulticulturalism in urban form terms, the dissertation chooses the position of a‘civility of indifference’, developed by Amin (2012), as one of many possiblestances within this discourse as an operative conception for such an exercise.Adopting the logical argumentation as the research strategy, the thesis delvesdeep into the conceptual domain mapped by space syntax theory as a primarysystem in this endeavour, and accordingly, describes how the spatial form of thecity, by way of human movement, has the potential to create a variety of socialgroupings. Thereupon the thesis develops a secondary conceptual system withexplanatory applicability to the relation between multiculturalism and spatialform. Supported by these systems of argumentation, the study describes how thespatial morphology of the city may have influence on the situation of livingtogether. It is suggested that overlapping spaces represent the spaces whereurban structure potentially can provide the spatial viability for the emergence ofa ‘civility of indifference’ and its two organizing principles of co-presence andmultiplicity.Hence, the dissertation intends to contribute to theoretical efforts into theexperience of living ‘together-in-difference’ from architectural and urban designperspectives, and argues that multiculturalism distinctly possesses spatialdimensions, which should be conceptualized and addressed through thetheoretical lens of spatial form. Hence, the thesis defends that notwithstandingbeing a complex of social processes, the spatial dimensions of multiculturalismshould not be belittled in efforts to address the situation of living together in themulticultural cities of the West. / <p>QC 20150522</p>

This thesis presents two chapters on credence goods and one on ongoing partnerships in an infinitely repeated game. The chapters on credence goods focus on the welfare and efficiency of equilibria in overcharging models of credence goods, something which has not been explicitly addressed before. The chapter on partnerships presents a theory explaining ongoing partnerships as solving a commitment problem for clients. There is a small literature on partnerships, and this chapter represents a novel but complimentary approach to that literature. At core, chapters 2, 3 and 4 of this thesis ask the following questions respectively: Do competition and information increase welfare in credence goods markets? How do customers in credence goods markets discipline experts from committing fraud? Can these strategies be welfare ranked? Why do ongoing partnerships exist? What problem do they solve?