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Ce travail de thèse est une contribution à l’étude de la réponse mécanique en grandes transformations du polyéthylène. Dans une première partie, des observations expérimentales sont données sur la réponse mécanique dépendante du temps de polyéthylènes contenant une large gamme de fractions cristallines. Dans une seconde partie, un modèle de comportement viscoélastique-viscoplastique est développé pour reproduire, lorsque le taux de cristallinité évolue, la transition progressive entre la réponse mécanique typique des thermoplastiques et celle plus typique des élastomères. Afin d’identifier les paramètres du modèle, une méthode déterministe analytique et une méthode numérique, basée sur un algorithme génétique, sont développées. Dans une troisième partie, le modèle de comportement proposé est implanté dans un code de calculs par éléments finis et utilisé pour prédire la réponse d’échantillons multi-couches de polyéthylènes à différentes fractions cristallines. Des comparaisons entre les simulations et les données expérimentales (en termes de réponse mécanique et d’évolution de la striction) mettent en évidence les capacités prédictives du modèle proposé. / This PhD dissertation deals with the large-strain mechanical response of polyethylene. In a first part, experimental observations are reported on the time-dependent mechanical response of polyethylene materials containing a wide range of crystal fractions. In a second part, a large-strain viscoelastic-viscoplastic constitutive model is developed to capture the progressive transition from thermoplastic-like to elastomeric-like mechanical response of polyethylene materials, as the crystal content changes. In order to identify the model parameters, an analytical deterministic scheme and a practical, “engineering-like”, numerical tool, based on a genetic algorithm are developed. In a third part, the proposed constitutive model is implemented into a finite element code and used to predict the response of multi-layered polyethylene specimens with different crystal fractions. Comparisons between the simulations and the experimental data (in terms of mechanical response and necking evolution) point out the model predictive capabilities.

Ce travail, basé sur une étude normative du développement et non sur une étude économique du droit. démontre que le concept d développement Influence dans certains cas l'Interprétation et l'application du droit international des investissements. Le concept du développement est utilisé sous diverses acceptions: le développement économique, le niveau de développement des États et le développement sous sa forme durable. Sous ces formes, son influence s'observe à deux niveaux: celui de l'identification et celui de la protection des investissements Internationaux. Référence est faite à la contribution d'une activité au développement économique de son État d'accueil pour identifier un Investissement: le concept est, de même, parfois utilisé lorsqu'il s'agit de déterminer l'étendue de la protection due aux Investissements internationaux. Ici, c'est le niveau de développement et le développement durable qui sont utilisés pour évaluer la protection effectivement due aux investissements Internationaux. La protection est ici considérée dans un sens tata Sens : elle englobe aussi la protection financière. La thèse fait valoir que l'utilisation du concept est très contestable pour Identifier un Investissement, alors que son Influence est plus palpable au niveau de l'application des normes relatives à la protection des Investissements. Dans ce sens, la thèse explique que le concept produit des effets plus concrets sur le droit international des investissements lorsque son utilisation se fonde sur certains principes ou s'accompagne de certaines techniques juridiques. En filigranes le travail critique aussi l'approche adoptée par les juristes lors de l'étude du développement. / This study, based on a normative study of development and not on an economic study of law, shows that the concept of development sometimes influences the interpretation and the enforcement of international investment law. The concept of development used in this study threefolds : it combines economic development, the level of development of States and sustainable development. Under these forms, its influences is perceive at two levels: that of the identification and of the protection of international investments. Indeed, the contribution of an activity to the economic development of the host State is used to identify an investment. The concept is also used when determining the scope of protection due to foreign investments. Here is the level of development and the concept of sustainable development which are used to assess the protection due to international investment. Protection is considered here in a broad sense: it also includes the financia1 protection of investments. The thesis argues that the use of the concept is highly questionable to identify an investment, while its influence is noteworthy in the enforcement of the investment protection principles. In this vein, the thesis explains that the concept produces more tangible effects on international investment law when its use is grounded on certain legal principles or techniques. In the work's background pattern lurks some critics of the method used by jurists in the study of development.

To date, relatively little research has investigated participants’ ability to monitor their memory for faces and names. Four experiments were conducted with aim of developing a comprehensive profile of memory monitoring performance during face identification tasks. In each experiment, memory monitoring judgements were solicited during encoding and/or retrieval of unfamiliar face-name pairs. In general, subjective estimates of future and past memory performance were valid predictors of objective memory performance, regardless of whether a face or name was the item to be retrieved from memory. As a test of the stability of memory monitoring accuracy across different categories of stimuli, memory monitoring for face-name pairs was compared with noun-noun pairs. The predictive validity of estimates of future memory performance was similar across the categories of stimuli, but the predictive validity of estimates of past memory performance was superior for nouns compared with names. A subset of the studies examined the influence of face and name distinctiveness on memory and memory monitoring for face-name associations. This was done in an attempt to identify sources of information that individuals might use to monitor their memory during face-name learning. The beneficial effects of distinctiveness on associative memory were symmetrical between faces and names, such that relative to their typical counterparts, distinct faces enhanced memory for names, and distinct names enhanced memory for faces. These effects were also apparent in memory monitoring. Estimates of future and past memory performance were greater for face-name associations that contained a distinct face or name compared with a typical face or name, regardless of whether the distinct item was a cue or target. Moreover, the predictive validity of prospective monitoring improved with name distinctiveness, whereas the predictive validity of retrospective monitoring improved with facial distinctiveness. Altogether, the results of the dissertation indicate that participants can monitor their memory for faces and names at a level above chance, that retrospective metamemory is more accurate for nouns compared with names, and that distinctiveness not only affects the strength of the association between a face and a name, but also the ability to monitor that association.

Current online identification techniques are recursive and involve local search techniques. In this thesis, we show how genetic algorithms, a parallel, global search technique emulating natural genetic operators can be used to estimate the poles and zeros of a dynamical system. We also design an adaptive controller based on the estimates. The algorithms are shown to be useful for continuous time parameter identifications and to be able to identify directly physical parameters of a system. Simulations and an experiment show the technique to be satisfactory and to provide unbiased estimates in presence of colored noise. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

M.Sc. / A Smart Card looks like a normal plastic card that we use every day, but its capabilities and advantages are huge. Inside the card there is a small microprocessor capable of doing operations on data. With memory available on the card, data can be stored in a safe and secure location. This card can be used for various applications and is a big improvement on all of its predecessors. These applications can be anything from SIM cards in a cell phone to credit cards and cards used for access control. The Smart Card offers us better security and offline identification because of its own embedded microprocessor. The combination of Smart Cards with biometrics for security reasons will be a logical step and the ideal way to identify the person as the true owner of the card. This dissertation will investigate the use of contact Smart Cards in the University environment, more specifically as a University student card. The Smart Card will be combined with a fingerprint to enforce better security. The main purpose is to use the Smart Card and the biometric property for access control at various places on campus.

M.Ing. (Electrical And Electronic Engineering) / Iris recognition systems have attracted much attention for their uniqueness, stability and reliability. This recognition system is composed of four main modules, namely, iris acquisition, iris segmentation, feature extraction and encoding and - nally iris matching. However, performance of this system is a ected by poor image quality. In this research, a novel iris image quality assessment method based on character component is presented. This method is composed of two steps, individual assessment of character quality parameters and fusion of estimated quality parameters using Principal Component Analysis (PCA). The de ned quality parameters considered in this research are entropy, sharpness, occlusion, dilation, area ratio, contrast and blur. The designed technique was tested on three databases: Chinese Academy of Science Institute of Automation (CASIA), University of Beira Interior (UBIRIS) and Internal Collection (IC). Individual assessment of quality parameters has shown that dilation, sharpness and blur have more in uence on the quality score than the other parameters. The images were classi ed into two categories (good and bad) by human visual inspection. The e ect of the individual parameters on each database is illustrated, with CASIA exhibiting higher quality scores than the UBIRIS and IC databases. Support Vector Machine (SVM) and Linear Discriminant Analysis (LDA) were used to evaluate the performance of the proposed quality assessment algorithm. A k-fold cross validation technique was employed to the classi ers to obtain unbiased results. Two performance measures were used to rate the proposed algorithm, namely, Correct Rate (CR) and Area Under the Curve (AUC). Both performance measures showed that SVM classi er outperforms LDA in correctly classifying the quality of the images in all three databases. The experimental results demonstrated that the proposed algorithm is capable of detecting poor quality images as it yields an e ciency of over 84% and 90% in CR and AUC respectively. The use of character component to assess quality has been found to be su cient, though there is a need to develop a better technique for standardization of quality. The results found using a SVM classi er a rms the proposed algorithm is well-suited for quality assessment.

The streptococci, as a group, are gram positive cocci which occur in pairs or chains; they are nonmotile, nonsporing, and catalase negative. Most species are facultative anaerobes, and a few are obligate anaerobes. They are chemorganotrophs producing lactic acid as an end product of glucose metabolism. The G + C (guanine + cytosine) content reported for 15 species is 33-42% (Diebel and Seeley, 1974). The genus Streptococcus includes a large number of saprophytic, pathogenic and non pathogenic species. Many of these bacteria are members of the normal body flora. However, man is very susceptible to the pathogenic members, and no organ in the body is completely immune to streptococcal infections. As a result, streptococci cause a greater variety of clinical manifestations than any other genus of bacteria. As far as it known, no biochemical, physiological, or antibiogram pattern studies have been done on streptococci from Stockton or other parts of California. Therefore it is the purpose of this investigation to biochemically and physiologically characterize primarily extra-respiratory streptococcal isolates, study their antibiogram patterns, and relate these characteristics to each other and to other patterns reported in the United States.

The recent realization that coagulase-negative staphylococci are of medical importance led to a number of studies which attempt to characterize them more adequately. These studies have shown that the coagulase-negative staphylococci represent a “complex” of several species. Kloos and Schleifer, who are credited with the major effort to characterize the group, list (1975b) nine species: S. epidermidis, S. saprophyticus, S. capitis, S. cohnii, S. haemolyticus, S. hominis, S. simulans, S. wylosus, and S. warneri. Hajek (1976) added a new one, S. intermedius, isolated from animals; Kloos et al. (1976b) described S. sciuri, and Deviese et al. (1978) transferred Micrococcus hyicus to the genus Staphylococcus, for a total of 12 species. Kloos and Schleifer (1975b) introduced a simplified scheme in the form of a flow chart (Figure 1) for routine identification of nine of these staphylococci. In OCtober of 1980 I began a study of this group with the purpose of conducting biochemical tests on clinical isolates from Stockton, California and, hopefully, expanding and updating the system that was introduced by Kloos and Schleifer. My system, henceforth referred to as the L-K Scheme, utilizes biochemical tests already available in clinical laboratories. Its purpose was to determine if the isolates used in this study can be placed in homogeneous groups.

目的：國內中藥材品種混亂的現象普遍，而香港的中藥材大多是由國內進口，其中相當部分將轉口至世界各地，中藥材品種混亂的問題對本港乃至各地都有影響。本課題旨在對香港藥食兩用中藥材進行調研整理和鑒別研究。通過市場調查獲得香港市場流通過程中的藥食兩用的中藥材、中藥飲片品種的商品規格、價格、產地資訊。獲取藥食兩用中藥材和中藥飲片的代用品、偽劣品種和品種混淆的情況。通過品種考證鑒定香港市面流通中藥材混淆品種的基源。發現存在的問題並提出解決意見。 方法：通過實地走訪調查、詢問、填寫調查表等方式，對香港十八個行政區的中藥批發商、中藥零售企業、食品零食商進行調查，並拍攝被調查的藥材和飲片、替代品、混淆品的照片作為影像記錄。 結果：1）香港藥食兩用藥材價格差異大，質量參差不齊 2）中藥規格等級劃分混亂，價格透明度低。3）香港部份市售的中藥材小薊、枳椇子、金銀花、青果、昆布、薏苡仁、酸棗仁、鮮白茅根、枸杞子、山藥基原與藥典存在差異。4 ）根據大棗的歷史沿革，推斷案（大棗、黑棗）為鼠李科植物棗Ziziphus jujuba Mi11.的成熟果實。 討論：1）香港藥食兩用中藥材存在基原混亂、規格劃分不統一、質量不穩定等問題。2）為保證中藥材質量，建議《香港中藥材標準》強制實施。3）開展基礎研究，開發新資源，尋找中藥代用品。4）完善中醫藥相關法律法規，嚴格監控中藥生產、購進、銷售各環節。5）發展高質量、高附加值的中藥產業。 關鍵詞：藥食兩用、中藥材、調查整理、性狀鑒別。