Atlantic horseshoe crabs (Limulus polyphemus) have endured decades of intense harvest pressure. Genetics studies have shown evidence of distinct sub-groups spanning the coast, although few fine-scale studies have been done to delineate these groups on a local level. Massachusetts lies directly between two of these sub-groups. With documented differences in prosomal widths of horseshoe crabs from either side of Cape Cod, it is possible that Cape Cod is a barrier to gene flow and that there are two distinct genetic groups within Massachusetts. Regulations currently consider all horseshoe crabs to be of one stock. I examined 6 microsatellite loci from 193 horseshoe crabs collected from 7 locations across Massachusetts between 5 May and 24 June 2010. I also analyzed the prosomal widths of 324 horseshoe crabs from 8 locations across Massachusetts. Data analysis revealed low divergence with a G′ST of 0.005 (95% CI −0.004–0.013) and a G″ST of 0.015 (95% CI −0.014–0.045). Wellfleet Bay showed evidence of divergence from all other sites except Buzzards Bay. Isolation by distance is apparent via the Atlantic Ocean. Phenotypic variation in the prosomal widths of horseshoe crabs shows greater divergence among sites than neutral markers and indicates the presence of additive genetic effects. Low divergence and high heterozygosity indicate that although documented population declines have occurred, effective population size (Ne) is still large enough to maintain allele frequencies. With isolation by distance, divergence is likely to increase over time if populations remain low. Phenotypic divergence shows the possibility of local adaptation and that the implementation of management units (MUs) to the north and south of Cape Cod would be recommended as a conservative measure.

An analytical model of cracked composite beams vibrating in coupled bending-torsion is developed. The beam is made of fiber-reinforced composite with fiber angles in each ply aligned in the same direction. The crack is assumed open. The local flexibility concept is implemented to model the open crack and the associated compliance matrix is derived. The crack introduces additional boundary conditions at the crack location and these effects in conjunction with those of material properties are investigated. Free vibration analysis of the cracked composite beam is presented. The results indicate that variation of natural frequencies in the presence of a crack is affected by the crack ratio and location, as well as the fiber orientation. In particular, the variation pattern is different as the magnitude of bending-torsion coupling changes due to different fiber angles. When bending and torsional modes are essentially decoupled at a certain fiber angle if there is no crack, the crack introduces coupling to the initially uncoupled bending and torsion. Based on the crack model, aeroelastic characteristics of an unswept composite wing with an edge crack are investigated. The cracked composite wing is modeled by a cracked composite cantilever and the inertia coupling terms are included in the model. An approximate solution on critical flutter and divergence speeds is obtained by Galerkin's method in which the fundamental mode shapes of the cracked wing model in free vibration are used. It is shown that the critical divergence/flutter speed is affected by the elastic axis location, the inertia axis location, fiber angles, and the crack ratio and location. Moreover, model-based crack detection (size and location) by changes in natural frequencies is addressed. The Cawley-Adams criterion is implemented and a new strategy in grouping frequencies is proposed to reduce the probability of measurement errors. Finally, sensitivity of natural frequencies to model parameter uncertainties is investigated. Uncertainties are modeled by information-gap theory and represented with a collection of nested sets. Five model parameters that may have larger uncertainties are selected in the analysis, and the frequency sensitivities to uncertainties in the five model parameters are compared in terms of two immunity functions. / Ph. D.

Radio frequency system optimization and troubleshooting remains one of the most challenging aspects of working in a cellular network. To stay competitive, cellular providers continually monitor the performance of their networks and use this information to determine where to improve or expand services. As a result, operators are saddled with the task of wading through overwhelmingly large amounts of data in order to trouble-shoot system problems. Part of the difficulty of this task is that for many complicated problems such as hand-off failure, clues about the cause of the failure are hidden deep within the statistics of underlying dynamic physical phenomena like fading, shadowing, and interference. In this research we propose that Hidden Markov Models (HMMs) be used as a method to infer signature statistics about the nature and sources of faults in a cellular system by fitting models to various time-series data measured throughout the network. By including HMMs in the network management tool, a provider can explore the statistical relationships between channel dynamics endemic to a cell and its resulting performance. This research effort also includes a new distance measure between a pair of HMMs that approximates the Kullback-Leibler divergence (KLD). Since there is no closed-form solution to calculate the KLD between the HMMs, the proposed analytical expression is very useful in classification and identification problems. A novel HMM based position location technique has been introduced that may be very useful for applications involving cognitive radios. / Ph. D.

Cette thèse présente trois contributions en lien avec l'apprentissage et la détection de dissimilarité statistique multivariée, problématique d'importance primordiale pour de nombreuses méthodes d'apprentissage utilisées dans un nombre croissant de domaines. La première contribution introduit la notion de taille d'effet multivariée non-paramétrique, éclairant la nature de la dissimilarité détectée entre deux jeux de données, en deux étapes. La première consiste en une décomposition d'une mesure de dissimilarité (divergence de Jensen-Shannon) visant à la localiser dans l'espace ambiant, tandis que la seconde génère un résultat facilement interprétable en termes de grappes de points de forte discrépance et en proximité spatiale. La seconde contribution présente le premier test non-paramétrique d'homogénéité séquentiel, traitant les données issues de deux jeux une à une--au lieu de considérer ceux-ci- in extenso. Le test peut ainsi être arrêté dès qu'une évidence suffisamment forte est observée, offrant une flexibilité accrue tout en garantissant un contrôle del'erreur de type I. Sous certaines conditions, nous établissons aussi que le test a asymptotiquement une probabilité d'erreur de type II tendant vers zéro. La troisième contribution consiste en un test de détection de changement séquentiel basé sur deux fenêtres glissantes sur lesquelles un test d'homogénéité est effectué, avec des garanties sur l'erreur de type I. Notre test a une empreinte mémoire contrôlée et, contrairement à des méthodes de l'état de l'art qui ont aussi un contrôle sur l'erreur de type I, a une complexité en temps constante par observation, le rendant adapté aux flux de données. / In this thesis, we study problems related to learning and detecting multivariate statistical dissimilarity, which are of paramount importance for many statistical learning methods nowadays used in an increasingly number of fields. This thesis makes three contributions related to these problems. The first contribution introduces a notion of multivariate nonparametric effect size shedding light on the nature of the dissimilarity detected between two datasets. Our two step method first decomposes a dissimilarity measure (Jensen-Shannon divergence) aiming at localizing the dissimilarity in the data embedding space, and then proceeds by aggregating points of high discrepancy and in spatial proximity into clusters. The second contribution presents the first sequential nonparametric two-sample test. That is, instead of being given two sets of observations of fixed size, observations can be treated one at a time and, when strongly enough evidence has been found, the test can be stopped, yielding a more flexible procedure while keeping guaranteed type I error control. Additionally, under certain conditions, when the number of observations tends to infinity, the test has a vanishing probability of type II error. The third contribution consists in a sequential change detection test based on two sliding windows on which a two-sample test is performed, with type I error guarantees. Our test has controlled memory footprint and, as opposed to state-of-the-art methods that also provide type I error control, has constant time complexity per observation, which makes our test suitable for streaming data.

This dissertation is an exploratory study aimed at empirically identifying and examining manifestations of communication barriers in the South African National Defence Force. A convergence model of communication is presented, describing the stages involved when individuals share the same information. The convergence model of communication delineates the relationship among the physical, psychological, and social aspects of communication. Two complementary theorems deduced by Kincaid (1988) from the convergence principle and the basic cybernetic process involved in information processing are applied in the analyses. The theorems specify the conditions under which intercultural communication will lead to convergence between members of different cultures involved. An empirically testable model was developed to collect information about possible communication barriers. The barriers are an indication of the restrictions on communication in the system and therefore indicate the possibility of restricting cultural convergence. / Communication / M.A. (Communication)

雙重股權結構現今於美國公司治理上的應用越來越普遍，在此股權結構下的公司透過具不同投票權的股票達到控制權與盈餘分配權分離，使內部經理人可以掌握公司的控制權，但相應而生的可能是經理人與股東間的代理問題，且並非所有等級的股票皆公開在市場上交易，這也使得公司資訊透明度降低，進而影響股票的流動性和公司價值，然而，對於雙重股權結構亦有研究持正面看法，如公司可藉控制權集中提升經營效率等。本研究由此為出發點，欲以聯貸市場的角度來檢驗雙重股權結構公司在進行聯貸時，是否會對聯貸條件產生影響，而貸款銀行面對公司的雙重股權結構又將採取何種風險評估角度。 本研究利用1991至2012年間美國公司的資料，研究結果顯示公司在雙重股權結構下，所獲得之聯貸條件並未呈現負面影響，其中原因可能存在於雙重股權結構的公司特性與其可能為公司創造的價值。

Dans le cadre d’une sociologie des organisations portant sur les liens entre organisations télévisuelles et environnement, la présente thèse a pour objectif de cerner les modalités du développement récent de la télévision au Québec en le comparant à celui de la Belgique francophone et de la Suisse. Une telle comparaison repose sur un principe méthodologique simple: on cerne d’autant mieux la réalité que l’on étudie si on peut la comparer à une réalité équivalente d’autres sociétés. En s’appuyant sur des théories de développement organisationnel reliées au courant néo-fonctionnaliste et en adaptant des « histoires de cas » d’études organisationnelles à la réalité télévisuelle des années 90 et 2000, le chercheur a mis au point une grille de classification des données permettant d’étudier les composantes du développement de la télévision dans trois « petites » sociétés industrialisées. Dans un premier temps, il a pu constater une augmentation très importante du nombre de chaînes de télévision par rapport à ce qu’il était dans les années 50 à 70, le tout encadré par les autorités réglementaires en place. Par la suite, dans chacune de ces trois sociétés et sur une période de vingt-cinq ans, il a pu préciser les interactions et échanges entre organisations télévisuelles et environnement lesquels ont été, selon les cas, harmonieux, difficiles, voire même conflictuels. Après avoir comparé les modalités d’une telle augmentation entre les trois sociétés, le chercheur a pu constater une convergence de surface. On note bien quelques similitudes entre les trois sociétés, mais, surtout, chacune d’entre elles est restée sur son quant-à-soi. En Suisse, l’importance accordée au consensus social a favorisé un développement équilibré de l’augmentation des chaines. En Belgique, pays aux divisions profondes constamment réaffirmées, les oppositions ont permis, malgré tout, l’édification d’un ensemble audiovisuel relativement stable. Au Québec, avec une augmentation exponentielle du nombre de chaines, on a assisté à un véritable surdéveloppement de la télévision encouragé et planifié par les autorités gouvernementales canadiennes en réaction à un supposé envahissement culturel américain. Le CRTC, la régie des ondes canadiennes, a pesé de tout son poids pour favoriser l’augmentation du contenu canadien et de la production locale. Par ailleurs, cette augmentation s’est faite avec des ressources limitées. On en fait trop avec trop peu. C’est ce qui permettrait d’expliquer la baisse de qualité de la télévision québécoise contemporaine. Comme élément de solution aux problèmes que la télévision québécoise connait présentement, il faudrait considérer cette dernière pour ce qu’elle est véritablement: une petite télévision dans un univers industriellement hautement développé. Si une telle conception est très bien acceptée aussi bien en Belgique qu’en Suisse, elle ne l’est pas au Québec / The following thesis is an organizational analysis of the recent development of television in Switzerland, French Belgium and Québec. The main interactions between different television organisations of these three societies are studied to understand how each of them coped with the very important increase of television channels that most of the industrialized countries have encountered in the last twenty-five years or so. This organizational study is based upon the following principle: one may more easily grasp the specifics of a given society when it is compared to similar specifics of other societies. By considering the development of television as a social itinerary in each of these three societies, it becomes possible to see how values, interests, coalitions as well as conflicts played a vital role in a new multi-channels television environment. In so doing, the inevitable comparison between Canadian and American television so often made in Canada is avoided. The gap is so big between these two countries that, for once, it is worth using units of comparisons of about the same size. At the end of this study, it becomes clear that regulatory bodies in each of the three societies set out policies and guidelines to strongly encourage more existing television channels. Accordingly, a certain convergence between these three societies does exist and the popular belief that a given market was left to itself in a new television environment cannot be no longer sustained. However, if there are some elements of convergence, elements of divergence are much more important. In Switzerland, the increase of television channels was made in an orderly manner since consensus between all kinds of organizations is a vital part of Swiss way of life. In Belgium, since conflicts are the fundamentals of the everyday life among political parties, cultural and linguistic communities, oppositions remained very important in this increase of television channels. However, one must recognize as an end result that, surprisingly, the whole television environment stays rather stable. Québec had a development of its own. CRTC, the Canadian regulatory body, is mainly responsible for an overdevelopment of Québec television since the television environment in Québec counts a surprisingly high number of television channels for such a small industrialized society. The whole thing was deliberately planned by CRTC as an answer to an everlasting Canadian fear: an American cultural invasion, a “danger” that yet has to be proven. However, this overdevelopment of television did not come with increased resources to support so many television channels. Québec television offers too much with too little. This might explain a certain loss of quality observed in Québec television over the recent years. Things would probably be much easier if, for once, Québec television was considered for what it is: a small television in a highly developed and industrialized world. If that kind of consideration goes without saying in Switzerland and Belgium, it still is not the case in Québec.

Ce mémoire a pour objectif de déterminer si les précipitations convectives estivales simulées par le modèle régional canadien du climat (MRCC) sont stationnaires ou non à travers le temps. Pour répondre à cette question, nous proposons une méthodologie statistique de type fréquentiste et une de type bayésien. Pour l'approche fréquentiste, nous avons utilisé le contrôle de qualité standard ainsi que le CUSUM afin de déterminer si la moyenne a augmenté à travers les années. Pour l'approche bayésienne, nous avons comparé la distribution a posteriori des précipitations dans le temps. Pour ce faire, nous avons modélisé la densité \emph{a posteriori} d'une période donnée et nous l'avons comparée à la densité a posteriori d'une autre période plus éloignée dans le temps. Pour faire la comparaison, nous avons utilisé une statistique basée sur la distance d'Hellinger, la J-divergence ainsi que la norme L2. Au cours de ce mémoire, nous avons utilisé l'ARL (longueur moyenne de la séquence) pour calibrer et pour comparer chacun de nos outils. Une grande partie de ce mémoire sera donc dédiée à l'étude de l'ARL. Une fois nos outils bien calibrés, nous avons utilisé les simulations pour les comparer. Finalement, nous avons analysé les données du MRCC pour déterminer si elles sont stationnaires ou non. / The main goal of this master's thesis is to find whether the summer convective precipitations simulated by the Canadian Regional Climate Model (CRCM) are stationary over time or not. In order to answer that question, we propose both a frequentist and Bayesian statistical methodology. For the frequentist approach, we used standard quality control and the CUSUM to determine if the mean has increased over the years. For the Bayesian approach, we compared the posterior distributions of the precipitations over time. In order to do the comparison, we used a statistic based on the Hellinger's distance, the J-divergence and the L2 norm. In this master's thesis, we used the ARL (average run length) to calibrate each of our methods. Therefore, a big part of this thesis is about studying the actual property of the ARL. Once our tools are well calibrated, we used the simulation to compare them together. Finally, we studied the data from the CRCM to decide, whether or not, the data are stationary.

A travers cette thèse, notre objectif de départ a été de comprendre en quoi l'atteinte des objectifs sociaux des PPP dépend des mesures prises par les gestionnaires publics dans le cadre de l'exercice de leurs rôles et responsabilités en matière de contrôle.C'est pourquoi il a été question pour nous de comprendre comment les pouvoirs publics au travers des dispositifs institutionnels et contractuels ont exercé ce rôle de contrôle sur le partenaire privé. Sur la base d'une telle orientation, il a été souscrit aux méthodes qualitatives notamment à l'étude de cas pour appréhender le contrôle dans les PPP. Sur l'institutionnalisation des axes comme la prise en compte de toutes les parties prenantes, les différences d'objectifs, les rôles et responsabilités, l'absence de hiérarchie ont été tour à tour analysés. Ce qui a permis d'en faire des préalables des PPP. S'agissant de la contractualisation, il a fallu s'intéresser aux modèles de contrôle qui étaient basés sur la nécessité d'apporter des corrections au système, et sur ceux qui créent les conditions d'imputabilité. En conclusion de ce point, il apparaitra que les contrats devraient s'appuyer sur des éléments de performance. Enfin, sur le traitement des divergences entre partenaires les différences d'objectifs, de valeurs et de caractéristiques, l'opportunisme des partenaires surtout privés, la nécessité d'une alliance et d'une coopération, le pragmatisme des partenaires ont été mis en avant. Autrement dit dans les PPP, il est nécessaire de procéder au management de telles divergences. / Through this PhD thesis, our initial objective was to understand the control exercised by the government on their private partners in the Public-Private Partnerships. This was necessitated by the differences in objectives of the partner institutions and their different characteristics.This is why it has been the question for us to understand how the authorities through the institutional and contractual arrangements exercised this role of control over the private partner.On the basis of such an approach, it was subscribed to qualitative methods including case study to understand the control on the PPP.On the institutionalization, axis such as the inclusion of all the stakeholders, the differences in objectives, the roles and responsibilities, the lack of hierarchy were alternately analyzed. This allowing to make them prerequisites to PPPs.With respect to contracting, we had to look at the control models which were based on the need to correct the system and on those which create the conditions of accountability. To conclude this point, it will appear that contracts should be based on elements of performance.Finally, on the treatment of the differences between partners, the differences in goals, values and characteristics, the opportunism of partners especially the private ones, the need for an alliance and cooperation, the pragmatism of partners have been highlighted. In other words in the PPP, it is necessary to manage such differences.

Les travaux de recherche menés dans cette thèse répondent à plusieurs problématiques concernant les Petites et Moyennes Entreprises (PME). Après un état de l'art et une proposition de classification des types de rationnement de crédit, les deux premières études s'interrogent sur l'accès des PME aux crédits bancaires : la première question concerne la prédiction du rationnement de crédit à partir des caractéristiques des PME, la deuxième est relative aux déterminants des conditions de crédit. Enfin, la troisième étude teste l'existence et les causes de la divergence des notations de crédit des PME. Les travaux économétriques menés dans ces trois études se sont appuyés sur deux échantillons différents : l'un construit à partir d'un questionnaire sur le rationnement du crédit envoyé à un panel de PME, l'autre contenant les PME clientes d'un établissement bancaire, ayant obtenu au moins un crédit sur la période d'étude de quatre ans. / This dissertation addresses several issues facing Small and Medium Enterprises (SMEs). The first three articles are focusing on SMEs' access to bank loans. This issue contains two areas for intervention. The first is the prediction of credit rationing decision based upon SMEs characteristics. The second relates to the determinants of credit terms. The fourth article approaches the issue of the existence and causes of split rating. Researches covered in this thesis are based on two different samples. The first sample was constructed from a credit rationing survey sent to an SMEs panel. The second sample was supplied by one French mutual bank and relates to information on its credit reports and credit history over the period from 2007 to 2010.