This thesis is concerned with the deformation and adhesion of thin elastic sheets that come into contact with an underlying substrate. The focus of this work is on the interplay between material and geometric properties of a system and how this interplay determines the equilibrium states of sheet and substrate, particularly in the regime of geometrically nonlinear deformations. We first consider the form of an elastic sheet that is partially adhered to a rigid substrate, accounting for deflections with large slope: the Sticky Elastica. Starting from the classical Euler Elastica we provide numerical results for the profiles of such blisters and present asymptotic expressions that go beyond the previously known, linear, approximations. Our theoretical predictions are confirmed by desktop experiments and suggest a new method for the measurement of material properties for systems undergoing large deformations. With the aim to gain better understanding of the initial appearance of blisters we next investigate the deformation of a thin elastic sheet floating on a liquid surface. We show that, after the appearance of initial wrinkles, the sheet delaminates from the liquid over a finite region at a critical compression, forming a delamination blister. We determine the initial blister size and the evolution of blister size with continuing compression before verifying our theoretical results with experiments at a macroscopic scale. We next study theoretically the deposition of thin sheets onto a grooved substrate, in the context of graphene adhesion. We develop a model to understand the equilibrium of the sheet allowing for partial conformation of sheet to substrate. This model gives phys- ical insight into recent observations of ‘snap-through’ from flat to conforming states and emphasises the crucial role of substrate shape in determining the nature of this transition. We finally present a theoretical investigation of stiction in nanoscale electromechanical contact switches. Our model captures the elastic bending of the switch in response to both electrostatic and van der Waals forces and accounts for geometrically nonlinear deflections. We solve the resulting equations numerically to study how a cantilever beam adheres to a fixed bottom electrode: transitions between free, pinned and clamped states are shown to be discontinuous and to exhibit significant hysteresis. The implications for nanoscale switch design are discussed.

This thesis consists of three chapters investigating the impact of immigrant language skills on Canadian wages. The first chapter, “Linguistic diversity among Canadian immigrants: 1981-2006”, describes the changes in linguistic diversity among Canadian immigrants, as measured by a preferred linguistic distance measure, the Levenshtein Distance (LD) Index, and documents socio-demographic characteristics of recent immigrants as well as their labour market performance based on their language capital at the time of entry. The LD is an approximation of immigrants’ language skills in the Canadian official languages and represents the “distance” of an immigrant’s reported language to the Canadian official languages. Using the 20% micro-data files of the Canadian Censuses between 1981 and 2006, I assign each immigrant an index number based on two language measures: mother tongue and home language. French and English are defined as the Canadian official languages in Quebec and outside of Quebec, respectively. The main findings suggest that although immigrants’ mother tongues became more “distant” to the Canadian official languages in both regions over time, the language skill of an average immigrant based on home language remained almost the same in Quebec, in particular, between 1981 and 1996. In terms of immigrants’ socio-demographic characteristics and their labour market performance, general patterns were similar across the two regions, although there were significant differences by language groups. In particular, the change in immigrants’ wages by language groups is suggestive of the role of language skills in determining wages. The second chapter, “Immigrant versus native men? Substitutability and the role of linguistic diversity in Canada”, estimates the degree of substitutability between immigrant and native men by incorporating immigrants’ language skills into the analysis and calculates the potential wage effects of immigration on Canadian wages. Using the 20% micro-data files of the Canadian Censuses between 1981 and 2006 and imposing a nested-CES production function on the Canadian economy, I estimate immigrant-native substitutability based on immigrants’ language skills in addition to education levels and years of labour market experience. I use the LD Index to represent immigrants’ language skills by the distance of the mother tongue and home language of an immigrant to English outside of Quebec and to French in Quebec. I define three language groups for immigrants as the high language-skilled, the medium language-skilled, and the low language-skilled. The key findings are as follows. First, home language-based estimates suggest imperfect substitutability in Canada outside of Quebec in some cases. Second, by language skill groups, the low language-skilled immigrants are more likely to be imperfect substitutes for the Canadian-born. Third, the findings for Quebec are substantially different from those for Canada outside of Quebec. My simulations suggest that the long-run effect of immigration on immigrants’ wages was negative between 1981 and 2006 while the long-run effect of immigration on the wages of the Canadian-born was small but positive over the same period. The third chapter, “Gender, linguistic diversity, and labour market substitutability”, uses the same methodology and data sources as in the second chapter to incorporate female workers into the analysis of immigrant-native substitutability. This study estimates the elasticity of substitution between immigrant language groups and natives for female workers and the pooled sample of male and female workers. The findings suggest that the degree of substitutability between female immigrants and female natives is similar to the degree of substitutability between male immigrants and male natives. The main results do not change for the pooled sample. Due to potential differences between language accumulation processes between female and male immigrants, the third chapter also estimates female-male immigrants substitutability based on language skills, education levels, and years of labour market experience. The findings suggest that female and male immigrants are imperfect substitutes outside of Quebec regardless of language measures.

In multi-view video applications, view synthesis is a computationally intensive task that needs to be done correctly and efficiently in order to deliver a seamless user experience. In order to provide fast and efficient view synthesis, in this thesis, we present a cloud-based implementation that will be especially beneficial to mobile users whose devices may not be powerful enough for high quality view synthesis. Our proposed implementation balances the view synthesis algorithm’s components across multiple threads and utilizes the computational capacity of modern CPUs for faster and higher quality view synthesis. For arbitrary view generation, we utilize the depth map of the scene from the cameras’ viewpoint and estimate the depth information conceived from the virtual camera. The estimated depth is then used in a backward direction to warp the cameras’ image onto the virtual view. Finally, we use a depth-aided inpainting strategy for the rendering step to reduce the effect of disocclusion regions (holes) and to paint the missing pixels. For our cloud implementation, we employed an automatic scaling feature to offer elasticity in order to adapt the service load according to the fluctuating user demands. Our performance results using 4 multi-view videos over 2 different scenarios show that our proposed system achieves average improvement of 3x speedup, 87% efficiency, and 90% CPU utilization for the parallelizable parts of the algorithm.

New unsaturated coupled models have been developed for fluid transport in deformable rock by using modified mixture theory rather than a fully mechanics-based approach. These models include the following: an unsaturated hydro-mechanical coupled model for both non-swelling and swelling materials, in which a new coupled formulation for hydration swelling rock has been included; and an unsaturated hydro-mechanical-chemo coupled model, incorporating a new coupled formulation including osmosis flow and an unsaturated version of Darcy's law which has been extended by including osmosis effects.Modified mixture theory is mainly based on non-equilibrium thermodynamics. Helmholtz free energy is used to give the energy relationship between the fluids and solid and, by using the Gibbs-Duhem equation, the interactions between different fluids such as gas, water and chemical can be obtained. In this research, general coupled formulations for both large small and deformations have been obtained. For swelling rocks, the water between the clay platelets can be modeled by including the difference between the free energy of whole domain and that of the pore water plus the solid skeleton. By assuming small deformations, the final equations can be compared with those derived using the mechanics approach.The new coupled models have been tested by carrying out simple benchmark numerical simulations using finite elements. Problems analyzed include: (1) the consolidation of saturated swelling rocks in which the hydration swelling effects on consolidation have been analysed in detail; (2) the desaturation and resaturation of seasonally affected rocks around tunnels; (3) the desaturation stage for swelling rocks used in the containment of nuclear waste disposal; (4) chemical transport in very low permeability rock used for nuclear waste disposal, in which particular attention has been focused on osmosis flow and chemical consolidation. In summary, this thesis extends modified mixture theory and develops new coupled formulations which can be applied to deep nuclear waste disposal, including tunnelling, drilling and chemical transport in low permeability host rock.

In this thesis we are interested in the propagation of low-frequency linear elastic waves through composite materials. We use a variety of dynamic homogenization techniques to find the effective elastic properties of some composites. We consider composites with isotropic phases for ease of exposition but the theory could easily be extended to anisotropic inclusions or host.We use a Representative Volume Element approach with the Method of Asymptotic Homogenization to model a random fibre-reinforced composite. The fibres are all aligned in the same direction and are taken to be of infinite extent, so the composite is essentially two-dimensional. For a random composite we have considered the anti-plane case for SH wave propagation and the in-plane case for P and SV elastic wave propagation, extending the previous published work of Parnell and Abrahams (2006), (2008a), in which a periodic fibre-reinforced composite was studied. We also show, for a simple example, that it is possible to extend the Representative Volume Element method to a three-dimensional particulate composite.In this thesis an Integral Equation Method for homogenization is also studied, with application to periodic fibre-reinforced composites. We have extended the work of Parnell and Abrahams (2008b), which considered SH wave propagation only, to the case of P and SV wave propagation.

The thesis presents the structural behaviour of fibre reinforced polymer (FRP) laminated composites based on 3D elasticity formulation and finite element modeling using Abaqus. This investigation into the performance of the laminate included subjecting it to various parameters i.e. different boundary conditions, material properties and loading conditions to examine the structural responses of deformation and stress. Both analytical and numerical investigations were performed to determine the stress and displacement distributions at any point of the laminates. Other investigative work undertaken in this study includes the numerical analysis of the effect of flexural deformation of the FRP strengthened RC slab. The formulation of 3D elasticity and enforced boundary conditions were applied to establish the state equation of the laminated composites. Transfer matrix and recursive solutions were then used to produce analytical solutions which satisfied all the boundary conditions throughout all the layers of the composites. These analytical solutions were then compared with numerical analysis through one of the commercial finite element analysis programs, Abaqus. Out of wide variety of element types available in the Abaqus element library, shells and solids elements are chosen to model the composites. From these FEM results, comparison can be made to the solution obtained from the analytical. The novel work and results presented in this thesis are the analysis of fully clamped laminated composite plates. The breakthrough results of fully clamped laminated composite plate can be used as a benchmark for further investigation. These analytical solutions were verified with FEM solutions which showed that only the solid element (C3D20) exhibited close results to the exact solutions. However, FEM gave poor results on the transverse shear stresses particularly at the boundary edges. As an application of the work above, it is noticed that the FEM results for the FRP strengthened RC slab, agreed well with the experimental work conducted in the laboratory. The flexural capacity of the RC slab showed significant increase, both at service and ultimate limit states, after FRP sheets were applied at the bottom surface of the slab. Given the established and developed programming codes, exact solutions of deflection and stresses can be determined for any reduced material properties, boundary and loading conditions, using Mathematica.

M.Ing. / Water demand prediction can be useful for future planning and has a significant economic effect on a city, town or suburb. There are numerous factors influencing water demand and therefore influencing the prediction thereof. The effect of each of these factors on the water demand is called the elasticity of that factor. The main aim of this study is to determine area and income elasticities of demand. This will enable the reader to predict water demand by taking stand size (area) and income into account. The stand value of each user was used as a surrogate for the income of that user. Another aim of this study is to compare average water demands for different cities and towns in Gauteng, South Africa with each other. Over 190 000 users' data were used for this study.

The impact of fuel price changes can be seen in practically all sectors of the United States economy. Fuel prices directly and indirectly influence the daily life of most Americans. The national economy as well as the high standard of living we have come to enjoy in the United States is run on gasoline. Since the late 1990's the days of cheap oil and $1.00 gallons of gas are clearly over, understanding the influences of fuel price is more important now than ever. Since 1998 regular gasoline prices have increased $0.22 per gallon per year on average through the present with little evidence suggesting this trend will slow down or reverse substantially. The drastic and permanent change to the status quo of fuel prices has potentially rendered traditional knowledge of fuel price elasticities inapplicable to current analysis. Obtaining accurate measures of fuel price elasticities is important as it is used as a measure of personal mobility and can be related to the quality of life the public is experiencing. Price elasticities are also used in determining the future revenue available for surface transportation projects. Traditionally, short-run fuel price elasticities are thought to be inelastic allowing transportation agencies to ignore short-run fuel price changes to some degree when creating future projects and evaluating its economic feasibility. By using driving data collected from The National Evaluation of a Mileage-based Road User Study the fuel price elasticity of vehicle-miles traveled (VMT), as well as the sensitivity of gas prices relative to a historical high price, were estimated for the first year study participants using a panel data set approach with linear regression. The short-run fuel price elasticity of VMT was determined to be -1.71 with a range of -1.93 and -1.48. The elasticities found were significantly higher than the average short-run fuel price elasticity of -0.45 but can be rationalized by the impact poor economic conditions as well as the historically high fuel prices experienced prior to the researches time table had on the individuals driving behavior. The results suggest current short-run elasticities are not inelastic, if this trend continues transportation agencies must re-evaluate how they predict the future funding available for surface transportation projects.

El presente trabajo de investigación tiene como finalidad determinar si es factible utilizar políticas de precios en base al tipo de elasticidad precio de la demanda del diario Peru.21 para el periodo 2008-2015.Así mismo, busca demostrar la existencia de variables exógenas que pueden afectar al precio y por ende al volumen de ventas del diario en estudio. Además, revela como el crecimiento del acceso a internet en el mercado peruano puede afectar en la circulación del diario Perú.21. Con el objetivo de identificar la relación existente entre la circulación del diario y el precio, se analizan las principales teorías que explican la elasticidad-precio, dando a conocer en qué medida la variación del precio de un producto puede afectar la cantidad demandada, así mismo se brinda información sobre el mercado de la prensa escrita en el Perú y como ha reaccionado ante el auge del internet. Luego, se diseña el modelo de regresión lineal a fin de explicar el comportamiento de la variable dependiente también llamada variable endógena que es la circulación del diario Perú.21 en función de las variables exógenas o denominadas independientes o explicativas como son el precio histórico anual del diario Perú 21, la inversión publicitaria en el diario, la inversión publicitaria en internet y el acceso a internet a nivel nacional. Dicho de otro modo, se realiza el modelo de regresión lineal múltiple con la finalidad entender cuáles son las variables más relevantes y como estas influyen en gran medida en la ecuación de la demanda. Finalmente, se consideran algunas recomendaciones que permitan mejorar la comercialización del diario Perú.21 dentro del mercado de diarios peruano, el cual está en constante cambio, debido al rápido avance de la tecnología en los medios de comunicación, con grandes expectativas de crecimiento en la ciudad de Lima y al interior del país. / The purpose of this research is to determine if it is feasible to use price policies based on the type of price elasticity of demand of Peru.21 for the period 2008-2015. Likewise, it seeks to demonstrate the existence of exogenous variables that may Affect the price and therefore the volume of sales of the newspaper under study. In addition, it reveals how the growth of internet access in the Peruvian market can affect the circulation of the newspaper Peru.21. In order to identify the relationship between daily circulation and price, the main theories that explain price elasticity are analyzed, revealing to what extent the variation of the price of a product can affect the amount demanded, as well Provides information on the market of the written press in Peru and how it has reacted to the rise of the internet. Then, the linear regression model is designed in order to explain the behavior of the dependent variable also called endogenous variable that is the circulation of the daily Peru.21 in function of the exogenous variables or denominated independent or explanatory as they are the annual historical price of the Newspaper Peru 21, advertising investment in the newspaper, advertising investment on the internet and internet access nationwide. In other words, the multiple linear regression model is performed in order to understand which variables are the most relevant and how they influence to a great extent the demand equation. Finally, some recommendations are considered to improve the marketing of the daily newspaper Peru.21 within the Peruvian newspaper market, which is constantly changing due to the rapid advance of technology in the media, with high expectations of growth in the market. City of Lima and inside of the country. / Trabajo de Suficiencia Profesional

Le fonctionnement des organismes vivants requiert la production deforces à grande échelle, pour des processus biologiques aussi diversque la motilité cellulaire, le développement embryonnaire, lacicatrisation ou encore la contraction musculaire. Dans de telssystèmes, les forces générées à l'échelle moléculaire par des moteursprotéiques sont transmises par des réseaux de fibres désordonnés,menant à des tensions actives à grande échelle. Les propriétésmacroscopiques passives de ces réseaux de fibres sont biencaractérisées. En revanche, ce problème de production de stress pardes unités actives microscopiques n'est pas résolu. Cette Thèseprésente une étude approfondie, par des méthodes théoriques etnumériques, de la transmission de forces dans les réseaux élastiquesde biopolymères. Je montre que la réponse linéaire, à faible force,des réseaux est remarquablement simple : elle est déterminée par laseule la géométrie des unités actives exerçant les forces. Aucontraire, lorsque les forces actives sont suffisamment importantespour provoquer le flambage non-linéaire des fibres, ces forces sontrectifiées par le réseau, et deviennent isotropiquementcontractiles. La contraction émergente qui en résulte est amplifiéepar la transmission de forces non-linéaire à travers le réseau. Cetteamplification du stress macroscopique est renforcée par le caractèredésordonnée du réseau, mais sature lorsque la densité d'unités activesest grande. Nos prédictions sont en accord quantitatifs avec desrésultats expérimentaux sur des tissus reconstitués et des réseauxd'actomyosine in vitro, et apportent un éclairage nouveau surl'influence de l'architecture microscopique des réseaux sur structuredes stress à l'échelle de la cellule et du tissu. / Large-scale force generation is essential for biological functionssuch as cell motility, embryonic development, wound healing and musclecontraction. In these processes, forces generated at the molecularlevel by motor proteins are transmitted by disordered fiber networks,resulting in large-scale active stresses. While fiber networks arewell characterized macroscopically, this stress generation bymicroscopic active units is not well understood. In this Thesis, Ipresent a comprehensive theoretical and numerical study of forcetransmission in elastic fiber networks. I show that the linear,small-force response of the networks is remarkably simple, as themacroscopic active stress depends only on the geometry of theforce-exerting unit. In contrast, as non-linear buckling occurs aroundthese units, local active forces are rectified towards isotropiccontraction, making the local geometry of force exertion irrelevant.This emergent contractility is amplified by non-linear forcetransmission through the network. This stress amplification isreinforced by the networks' disordered nature, but saturates for highdensities of active units. Our predictions are quantitativelyconsistent with experiments on reconstituted tissues and actomyosinnetworks, and that they shed light on the role of the networkmicrostructure in shaping active stresses in cells and tissue.