This dissertation analyzes problems related to matching in general networks and decision under uncertainty. Chapter 1 introduces the framework of convex matching games. Chapter 2 discusses three distinct applications of the framework. Chapter 3 develops a new test of choice models with expected utility. In Chapter 1, I use Scarf's lemma to show that given a convexity structure that I introduce, the core of a matching game is always nonempty, and the framework I introduce can accommodate general contracting networks, multilateral contracts, and complementary preferences. In Chapter 2, I provide three applications to show how the convexity structure is satisfied in different contexts by different assumptions. In the first application, I show that in large economies, the convexity structure is satisfied if the set of participants in each contract is small compared to the overall economy. The second application considers finite economies, and I show that the convexity structure is satisfied if all agents have convex, but not necessarily substitutable, preferences. The third application considers a large-firm, many-to-one matching market with peer preferences, and I show that the convexity structure is satisfied under convexity of preferences and a competition aversion restriction on workers' preferences over colleagues. In Chapter 3, I show that some form of cyclic choice pattern across distinct information scenarios should be regarded as inconsistent with a utility function that is linear in beliefs.

Li Wenjing. / "April 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 155-167). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Liu, Jian. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (p. 86-91). / Abstracts in English and Chinese. / Chapter 1 --- Introduction of Matching Mechanisms --- p.1 / Chapter 1.1 --- Background for College Admissions Problem --- p.1 / Chapter 1.2 --- Background for Internet Advertising Market --- p.3 / Chapter 2 --- Application I: College Admissions Problem Revisited --- p.6 / Chapter 2.1 --- Three Basic Mechanisms --- p.6 / Chapter 2.1.1 --- Boston Mechanism --- p.7 / Chapter 2.1.2 --- Gale-Shapley Student Optimal Mechanism --- p.9 / Chapter 2.1.3 --- Top Trading Cycles Mechanism --- p.11 / Chapter 2.2 --- College Admissions Mechanisms Around the World --- p.12 / Chapter 2.2.1 --- Serial Dictatorship in Turkey --- p.13 / Chapter 2.2.2 --- JUPAS in Hong'Kong SAR --- p.14 / Chapter 2.2.3 --- College Admissions in Mainland China --- p.16 / Chapter 2.3 --- Generalized Model for College Admissions: JUPAS Revisited --- p.19 / Chapter 2.4 --- Extension to Marriage Problem --- p.23 / Chapter 2.5 --- Strategy Analysis in Extended Marriage Problem --- p.27 / Chapter 2.6 --- Strategy Analysis in JUPAS --- p.30 / Chapter 2.7 --- Efficiency Investigation via Simulation --- p.33 / Chapter 2.7.1 --- Efficiency Definition --- p.33 / Chapter 2.7.2 --- Simulation Design --- p.36 / Chapter 2.7.3 --- Simulation Results --- p.38 / Chapter 3 --- Application II: Search Engines Market Model --- p.42 / Chapter 3.1 --- The Monopoly Market Model --- p.42 / Chapter 3.1.1 --- The Ex Ante Case --- p.43 / Chapter 3.1.2 --- The Ex Post Case --- p.45 / Chapter 3.1.3 --- Formulated As An Optimization Problem --- p.51 / Chapter 3.2 --- The Duopoly Market Model --- p.54 / Chapter 3.2.1 --- Competition for End Users in Stage I --- p.54 / Chapter 3.2.2 --- Competition for Advertisers in Stage II and III --- p.57 / Chapter 3.2.3 --- Comparison of Competition and Monopoly --- p.65 / Chapter 3.3 --- Numerical Results and Observations --- p.70 / Chapter 3.3.1 --- Baseline Setting --- p.71 / Chapter 3.3.2 --- Effect of Supplies --- p.74 / Chapter 3.3.3 --- Effect of Discount Factors --- p.75 / Chapter 4 --- Related Work --- p.78 / Chapter 5 --- Summary and Future Directions --- p.83 / Bibliography --- p.86

This dissertation quantitatively evaluates selected labor market policies in a search-matching model with skill heterogeneity where high-skilled workers can take temporary jobs with skill requirements below their skill levels. The joint posterior distribution of structural parameters of the theoretical model is obtained conditional on the data on labor markets histories of the NLSY79 respondents. The information on AFQT scores of individuals and the skill requirements of occupations is utilized to identify the skill levels of workers and complexity levels of jobs in the job-worker matches realized in the data. The model and the data are used to simulate the posterior distributions of impacts of labor market policies on the endogenous variables of interest to a policy-maker, including unemployment rates, durations and wages of low- and high-skilled workers. In particular, the effects of the following policies are analyzed: increase in proportion of high-skilled workers, subsidies for employing or hiring high- and low-skilled workers and increase in unemployment income.

In this dissertation, I investigate how government policies influence an individual's decision to search for and accept a job and/or crime opportunity. Chapter 1 looks at how long it takes for released inmates to find a job, and when they find a job, how their incarceration rate changes. The purpose is to predict the effects of a successful job placement program. An on-the-job search model with crime is used to model criminal behavior, derive the estimation method and analyze different types of policies. The results show the unemployed are incarcerated twice as fast as the employed and take on average four and a half months to find a job. Combining these results, it is demonstrated that reducing the average unemployment spell of criminals by two months reduces crime and recidivism by more than five percent. Chapter 2 incorporates crime into a search and matching model of the labor market. All workers, irrespective of their labor force status can commit crimes and the employment contract is determined optimally. The model is used to study, analytically and quantitatively, the effects of various labor market and crime policies such as unemployment insurance, hiring subsidies and the duration of jail sentences. For example, wage subsidies reduce unemployment, the crime rates of employed and unemployed workers, and improve society's welfare. Chapter 3 investigates a market where wholesalers search for retailers and retailers search for consumers. I show how the timing, targets and types of anti-drug policies matter. For instance, supply falls if the likelihood of apprehension rises when a network is established. Alternatively, if the cost of apprehension rises for wholesale dealers when a network is searching for consumers, then revenue sharing is distorted. Such a distortion will increase retail profits and aggregate supply. As an application, the model provides an alternative explanation for why the United States cocaine market saw rising consumption and falling prices during the 1980's. Specifically, the ``War on Drugs" distorted the cocaine market and increased supply.

Osteoarthritis and ageing have been shown to induce changes in the number and health of peripheral mechanoreceptors. Whilst position and movement awareness in the osteoarthritic knee have been studied extensively, little work to date has been produced on muscle force awareness in this subject group. Poor force acuity may contribute to muscle and joint pain and dysfunction, and additionally hinder rehabilitation efforts in an osteoarthritic population. Overestimation of the muscles forces required for a given task, resulting in greater joint compression forces, may aggravate and inflame osteoarthritic symptoms. Underestimation of required muscle forces may amplify existing joint instability, increasing the risk of injury in an osteoarthritic population. Additionally, both under and overloading of muscles during the rehabilitation process can delay the return to full function after injury.When regarding the neurological process of force coding, current debate centres on the relative importance of centrally generated motor command mediated 'sense of effort' versus the peripheral mechanoreceptor signalled 'sense of tension' as the dominant coding process, with central mechanisms favoured in the majority of studies published to date. The purpose of this study was to investigate muscle force awareness in the knee extensors and flexors and hands of subjects with and without knee joint osteoarthritis. Twenty one subjects with knee joint osteoarthritis and 23 age and gender matched subjects with no known knee pathology were evaluated. All subjects performed ipsilateral isometric force estimation and force matching tasks, at levels scaled to individual maximum voluntary capacity (MVC). Errors in estimation and matching acuity were normalised to reference targets (comparison force/reference force) giving a relative score (RS) to allow comparison across submaximal force levels with RS less than 1.0 indicating that subjects produced insufficient force and vice versa.Maximal voluntary capacity tests revealed significantly lower (p<0.05) peak knee extension torque (111.2 Nm versus 145.3 Nm), but similar peak knee flexion torque (46.1 Nm versus 45.4 Nm for osteoarthritis and control subjects respectively). A pattern of overestimation at low reference levels and underestimation at high reference levels was demonstrated by all subjects. In the lower limb, force appreciation differed significantly between muscle groups regardless of knee condition, with knee extensors demonstrating greater overall accuracy than knee flexors. There was a significant difference (p<0.05) in force estimation ability and a trend to significance (p=0.066) for force matching acuity across groups at the 10% MVC test level. A significant (p<0.05) group difference in grip force estimation ability between the lowest and highest target levels was demonstrated.It can be concluded that there are small differences in force acuity in osteoarthritis subjects at lower submaximal force targets when compared to healthy age matched peers. The notion of information redundancy, whereby no new proprioceptive inputs, regardless of origin, are able to effect an improvement in force acuity in a given situation has been demonstrated in previous studies that reported relatively stable force matching acuity at forces between 30% and 60% of maximal capacity. The poor comparative force perception demonstrated in this study by the osteoarthritis group at the lower submaximal test levels supports the notion that centrally generated copies of motor commands do not provide sufficient data to adequately encode force magnitude at low levels of force generation, evoking a greater reliance data received from peripheral mechanoreceptors. This has significant implications for this subject group given that the majority of daily tasks require only low levels of force generation. Given that perceptive acuity in a variety of sensory modalities has been shown to improve with training there may be a role for force perception training in older adults with osteoarthritis.

La recherche d'occurrences de gènes d'ARN dans les séquences<br /> génomiques est un problème dont l'importance est renouvelée par la<br /> découverte récente de très nombreux ARN fonctionnels, opérant<br /> souvent en interaction avec d'autres molécules.<br /><br />Le formalisme des réseaux de contraintes est approprié à cette problématique aussi bien sur le plan de la modélisation que sur les développements algorithmiques qu'il permet de proposer. <br /><br /> Après une analyse et une comparaison des outils existants plongés dans le cadre des réseaux de contraintes, nous<br /> montrons comment l'utilisation conjointe des réseaux de contraintes,<br /> des techniques de résolution associées et des algorithmes et<br /> structures de données du "pattern matching" permet de modéliser et de<br /> rechercher efficacement des motifs structurés en interaction (faisant<br /> intervenir plusieurs textes génomiques simultanément).

Cette thèse se situe dans le cadre du projet MISS (Mathématiques de l'Imagerie Stéréoscopique Spatiale) monté par le CNES en collaboration avec plusieurs laboratoires universitaires en 2007. Ce projet se donne l'objectif ambitieux de modéliser un satellite stéréoscopique, prenant deux vues non simultanées mais très rapprochées de la Terre en milieu urbain. Son but principal est d'obtenir une chaîne automatique de reconstruction urbaine à haute résolution à partir de ces deux vues. Ce projet se heurte toutefois à des problèmes de fond que la présente thèse s'attache à résoudre. Le premier problème est le rejet des matches qui pourraient se produire par hasard, notamment dans les zones d'ombres ou d'occlusion, et le rejet également des mouvements au sol (véhicules, piétons, etc.). La thèse propose une méthode de rejet de faux matches basée sur la méthodologie dite a contrario. On montre la consistance mathématique de cette méthode de rejet, et elle est validée sur des paires simulées exactes, sur des vérités terrain fournies par le CNES, et sur des paires classiques de benchmark (Middlebury). Les matches fiables restants représentent entre 40% et 90% des pixels selon les paires testées. Le second problème de fond abordé est la précision. En effet le type de stéréoscopie envisagé exige un très faible angle entre les deux vues, qui sont visuellement presque identiques. Pour obtenir un relief correct, il faut effectuer un recalage extrêmement précis, et calibrer le niveau de bruit qui permet un tel recalage. La thèse met en place une méthode de recalage subpixélien, qui sera démontrée être optimale par des arguments mathématiques et expérimentaux. Ces résultats étendent et améliorent les résultats obtenus au CNES par la méthode MARC. En particulier, il sera montré sur les images de benchmark Middlebury que la précision théorique permise par le bruit correspond bien à celle obtenue sur les matches fiables. Bien que ces résultats soient obtenus dans le cadre d'un dispositif d'acquisition précis (stéréoscopie aérienne ou satellitaire à faible angle), tous les résultats sont utilisables en stéréoscopie quelconque, comme montré dans beaucoup d'expériences.

<p><p>Microstrip structures became very attractive with the development of cost-effective dielectric materials. Among several techniques suitable to the analysis of such structures, the discrete mode matching method (DMM) is a full-wave approach that allows a fast solution to Helmholz equation. Combined with a full-wave equivalent circuit, the DMM allows fast and accurate analysis of microstrips lines on multilayered substrates.</p><p> </p><p>The knowledge of properties like dispersion and electromagnetic fields is essential in the implementation of such transmission lines. For this objective a MATLAB computer code was developed based on the discrete mode matching method (DMM) to perform this analysis.</p><p> </p><p>The principal parameter for the analysis is the utilization of different dielectric profiles with the aim of a reduction in the dispersion in comparison with one-layer cylindrical microstrip line, showing a reduction of almost 50%. The analysis also includes current density distribution and electromagnetic fields representation. Finally, the data is compared with Ansoft HFSS to validate the results.</p></p> / The German Aerospace Center has rights over the thesis work

In this paper we describe an approach for generating geometrically-parameterized integrated-circuit interconnect models that are efficient enough for use in interconnect synthesis. The model generation approach presented is automatic, and is based on a multi-parameter model-reduction algorithm. The effectiveness of the technique is tested using a multi-line bus example, where both wire spacing and wire width are considered as geometric parameters. Experimental results demonstrate that the generated models accurately predict both delay and cross-talk effects over a wide range of spacing and width variation. / Singapore-MIT Alliance (SMA)