The face is one of the best biometrics for person identification and verification related applications, because it is natural, non-intrusive, and socially weIl accepted. Unfortunately, an human faces are similar to each other and hence offer low distinctiveness as compared with other biometrics, e.g., fingerprints and irises. Furthermore, when employing facial texture images, intra-class variations due to factors as diverse as illumination and pose changes are usually greater than inter-class ones, making 2D face recognition far from reliable in the real condition. Recently, 3D face data have been extensively investigated by the research community to deal with the unsolved issues in 2D face recognition, Le., illumination and pose changes. This Ph.D thesis is dedicated to robust face recognition based on three dimensional data, including only 3D shape based face recognition, textured 3D face recognition as well as asymmetric 3D-2D face recognition. In only 3D shape-based face recognition, since 3D face data, such as facial pointclouds and facial scans, are theoretically insensitive to lighting variations and generally allow easy pose correction using an ICP-based registration step, the key problem mainly lies in how to represent 3D facial surfaces accurately and achieve matching that is robust to facial expression changes. In this thesis, we design an effective and efficient approach in only 3D shape based face recognition. For facial description, we propose a novel geometric representation based on extended Local Binary Pattern (eLBP) depth maps, and it can comprehensively describe local geometry changes of 3D facial surfaces; while a 81FT -based local matching process further improved by facial component and configuration constraints is proposed to associate keypoints between corresponding facial representations of different facial scans belonging to the same subject. Evaluated on the FRGC v2.0 and Gavab databases, the proposed approach proves its effectiveness. Furthermore, due tq the use of local matching, it does not require registration for nearly frontal facial scans and only needs a coarse alignment for the ones with severe pose variations, in contrast to most of the related tasks that are based on a time-consuming fine registration step. Considering that most of the current 3D imaging systems deliver 3D face models along with their aligned texture counterpart, a major trend in the literature is to adopt both the 3D shape and 2D texture based modalities, arguing that the joint use of both clues can generally provides more accurate and robust performance than utilizing only either of the single modality. Two important factors in this issue are facial representation on both types of data as well as result fusion. In this thesis, we propose a biological vision-based facial representation, named Oriented Gradient Maps (OGMs), which can be applied to both facial range and texture images. The OGMs simulate the response of complex neurons to gradient information within a given neighborhood and have properties of being highly distinctive and robust to affine illumination and geometric transformations. The previously proposed matching process is then adopted to calculate similarity measurements between probe and gallery faces. Because the biological vision-based facial representation produces an OGM for each quantized orientation of facial range and texture images, we finally use a score level fusion strategy that optimizes weights by a genetic algorithm in a learning pro cess. The experimental results achieved on the FRGC v2.0 and 3DTEC datasets display the effectiveness of the proposed biological vision-based facial description and the optimized weighted sum fusion. [...]

La reconnaissance faciale est l'une des meilleures modalités biomêtriques pour des applications liées à l'identification ou l'authentification de personnes. En effet, c'est la modalité utilisée par les humains; elle est non intrusive, et socialement bien acceptée. Malheureusement, les visages humains sont semblables et offrent par conséquent une faible distinctivité par rapport à d'autres modalités biométriques, comme par exemple, les empreintes digitales et l'iris. Par ailleurs, lorsqu'il s'agit d'images de texture de visages, les variations intra-classe, dues à des facteurs aussi divers que les changements des conditions d'éclairage mais aussi de pose, sont généralement supérieures aux variations inter-classe, ce qui rend la reconnaissance faciale 2D peu fiable dans des conditions réelles. Récemment, les représentations 3D de visages ont été largement étudiées par la communauté scientifique pour palier les problèmes non résolus dans la reconnaissance faciale 2D, qui sont notamment causés par les changements d'illumination et de pose. Cette thèse est consacrée à la reconnaissance faciale robuste utilisant les données faciales 3D, incluant la reconnaissance de visage 3D, la reconnaissance de visage 3D texturé ainsi que la reconnaissance faciale asymétrique 3D-2D. La reconnaissance faciale 3D, utilisant l'information géométrique 3D représentée sous forme de nuage de points 3D ou d'image de profondeur, est théoriquement non affectée par les changements dans les conditions d'illumination et peut facilement corriger, par l'application d'une approche de recalage rigide comme ICP, les changements de pose. Le principal défi réside dans la représentation, avec précision, de la surface faciale 3D, mais aussi dans le recalage robuste aux changements d'expression faciale. Dans cette thèse, nous concevons une approche efficace et performante pour la reconnaissance de visage 3D. Concernant la description du visage, nous proposons une représentation géométrique basée sur les cartes extended Local Binary Pattern (eLBP), qui décrivent de manière précise les variations de la géométrie locale de la surface faciale 3D; tandis qu'une étape combinant l'appariement local, basé 81FT, aux informations compositionnelles du visage et aux contraintes de configuration permet d'apparier des points caractéristiques, d'un même individu, entre les différentes représentations de son visage. Évaluée sur les bases de données FRGC v2.0 et Gavab DB, l'approche proposée prouve son efficacité. Par ailleurs, contrairement à la plupart des approches nécessitant une étape d'alignement précise et couteuse, notre approche, en raison de l'utilisation de l'appariement local, ne nécessite pas d'enrôlement dans des conditions de pose frontale précise et se contente seulement d'un alignement grossier. Considérant que la plupart des systèmes actuels d'imagerie 3D permettent la capture simultanée de modèles 3D du visage ainsi que de leur texture, une tendance majeure dans la littérature scientifique est d'adopter à la fois la modalité 3D et celle de texture 2D. On fait valoir que l'utilisation conjointe de ces deux types d'informations aboutit généralement à des résultats plus précis et plus robustes que ceux obtenus par l'un des deux séparément. Néanmoins, les deux facteurs clés de la réussite sont la représentation bimodale du visage ainsi que la fusion des résultats obtenus selon chaque modalité. Dans cette thèse, nous proposons une représentation bio-inspirée du visage, appelée Cartes de Gradients Orientés (Oriented Gradient Maps: OGMs), qui peut être appliqué à la fois à la modalité 3D et à celle de texture 2D. Les OGMs simulent la réponse des neurones complexes, à l'information de gradient dans un voisinage donné et ont la propriété d'être très distinctifs et robustes aux transformations affines d'illumination et géométriques. [...] / The face is one of the best biometrics for person identification and verification related applications, because it is natural, non-intrusive, and socially weIl accepted. Unfortunately, an human faces are similar to each other and hence offer low distinctiveness as compared with other biometrics, e.g., fingerprints and irises. Furthermore, when employing facial texture images, intra-class variations due to factors as diverse as illumination and pose changes are usually greater than inter-class ones, making 2D face recognition far from reliable in the real condition. Recently, 3D face data have been extensively investigated by the research community to deal with the unsolved issues in 2D face recognition, Le., illumination and pose changes. This Ph.D thesis is dedicated to robust face recognition based on three dimensional data, including only 3D shape based face recognition, textured 3D face recognition as well as asymmetric 3D-2D face recognition. In only 3D shape-based face recognition, since 3D face data, such as facial pointclouds and facial scans, are theoretically insensitive to lighting variations and generally allow easy pose correction using an ICP-based registration step, the key problem mainly lies in how to represent 3D facial surfaces accurately and achieve matching that is robust to facial expression changes. In this thesis, we design an effective and efficient approach in only 3D shape based face recognition. For facial description, we propose a novel geometric representation based on extended Local Binary Pattern (eLBP) depth maps, and it can comprehensively describe local geometry changes of 3D facial surfaces; while a 81FT -based local matching process further improved by facial component and configuration constraints is proposed to associate keypoints between corresponding facial representations of different facial scans belonging to the same subject. Evaluated on the FRGC v2.0 and Gavab databases, the proposed approach proves its effectiveness. Furthermore, due tq the use of local matching, it does not require registration for nearly frontal facial scans and only needs a coarse alignment for the ones with severe pose variations, in contrast to most of the related tasks that are based on a time-consuming fine registration step. Considering that most of the current 3D imaging systems deliver 3D face models along with their aligned texture counterpart, a major trend in the literature is to adopt both the 3D shape and 2D texture based modalities, arguing that the joint use of both clues can generally provides more accurate and robust performance than utilizing only either of the single modality. Two important factors in this issue are facial representation on both types of data as well as result fusion. In this thesis, we propose a biological vision-based facial representation, named Oriented Gradient Maps (OGMs), which can be applied to both facial range and texture images. The OGMs simulate the response of complex neurons to gradient information within a given neighborhood and have properties of being highly distinctive and robust to affine illumination and geometric transformations. The previously proposed matching process is then adopted to calculate similarity measurements between probe and gallery faces. Because the biological vision-based facial representation produces an OGM for each quantized orientation of facial range and texture images, we finally use a score level fusion strategy that optimizes weights by a genetic algorithm in a learning pro cess. The experimental results achieved on the FRGC v2.0 and 3DTEC datasets display the effectiveness of the proposed biological vision-based facial description and the optimized weighted sum fusion. [...]

<p>U okviru ovog rada je razvijen ravanski model koji sadrži sve važne aspekte interakcije vode, nanosa i zagađivača u prirodnim vodotocima. Model obuhvata procese<br />strujanja vode, oba oblika kretanja nanosa (suspendovani i vučeni), mehanizme<br />razmene mase između nanosa u suspenziji i nanosa u aktivnom sloju, deformacije korita usled erozije i deponovanja nanosnog materijala, mehanizme razmene<br />mase između nanosa u aktivnom sloju i aktivnom stratumu, kao i procese transporta nekonzervativne zagađuju&acute;ce materije koja je u interakciji sa nanosom preko<br />procesa adsorpcije/desorpcije. Formulisane jednačine transporta zagađivača obuhvataju njegovu pojavu u rastvorenom i adsorbovanom obliku. Razmena između<br />dva vida pojave zagađivača (rastvoreni i adsorbovani) je opisana preko kinetickih<br />procesa prvog reda, pri cemu je modelisanje koeficijenata razmene usko povezano<br />sa dostupnom povrˇsinom za adsorpciju. Sa druge strane, razmena između materije<br />adsorbovane na suspendovani nanos, odnosno materije adsorbovane na nanos u aktivnom sloju je neposredno vezana za nanosne procese uvlačenja zrna u suspenziju i<br />deponovanja istih iz suspenzije. Početni &scaron;ematski testovi su podrazumevali proveru<br />razvijenog algoritma za re&scaron;avanje advektivnih članova jednačina. Druga grupa &scaron;ematskih testova je podrazumevala implementaciju razvijenog modela transporta<br />zagađujuće materije, pri čemu su testirani i kvalitativno ocenjeni mehanizmi<br />razmene i interakcije. Za testiranje modela na primerima aluvijalnih vodotokova<br />izabrane su dve deonice reke Dunav. Prva lokacija se nalazi u pograniˇcnoj zoni<br />između Mađarske i Srbije gde su testirani aspekti modela koji se odnose na<br />proracun tečenja i pona&scaron;anje nanosa. Druga deoncia se nalazi kod Beograda<br />gde je, pored proračuna strujanja i nanosa, vr&scaron;ena analiza modela transporta zagađujuće materije obuhvatajući sve relevantne mehanizme i aspekte izučavanih<br />procesa. Upoređivanjem terenskih merenja i rezultata proračuna je konstatovano<br />da razvijeni model može simulirati interakciju vode, nanosa i zagađivača u prirodnim vodotocima sa zadovoljavajucom tačno&scaron;ću i pouzdano&scaron;ću.<br />&nbsp;</p> / <p>This work presents the development of a two-dimensional model for flow, sediment<br />and pollutant interaction in natural watercourses. The model incorporates water<br />flow computation, both aspects of sediment transport (suspended and bed-load),<br />the mechanisms of exchange between suspended and bed sediment, bed evolution<br />due to erosion and deposition, the mechanisms of exchange between active layer<br />and active stratum sediment, as well as the processes of nonconservative pollutant<br />transport including its interaction with sediment particles by adsorption/desorption.<br />Deriving the governing equations for pollutant transport included the dissolved and<br />adsorbed pollutant. The exchange between the dissolved and adsorbed pollutant<br />was described using a first order kinetic process, while the modeling of the exchange<br />coefficients remained closely related to the sediment surface available for adsorption.<br />On the other hand, the exchange between the pollutant adsorbed on suspended sediment and the pollutant adsorbed on active layer sediment was directly related<br />to the sediment processes of entrainment and deposition. Numerical tests included<br />the evaluation of the developed algorithm for advection terms. The second group<br />of numerical tests targeted the pollutant transport model, with the emphasis on<br />the mechanisms of exchange and interaction. For field test cases two reaches of the<br />Danube River were used. The first reach was located in the border area between<br />Hungary and Serbia. Field data collected there was used to analyze the developed<br />model&rsquo;s ability to simulate flow and sediment transport. Data collected on the second reach near Belgrade was used to perform flow, sediment and pollutant transport<br />simulations, taking into account all the relevant mechanisms of the studied processes.<br />Comparing the computed and measured values, it was concluded that the developed<br />model is able to simulate the interaction of flow, sediment and pollutant in natural<br />watercourses with acceptable precision and reliability.</p>

We employ two efficient parallel approaches to reduce a model arising from a semi-discretization of a controlled heat transfer process for optimal cooling of a steel profile. Both algorithms are based on balanced truncation but differ in the numerical method that is used to solve two dual generalized Lyapunov equations, which is the major computational task. Experimental results on a cluster of Intel Xeon processors compare the efficacy of the parallel model reduction algorithms.

ROLE OF THE YXKO GENE OF BACILLUS SUBTILIS IN RESPONCE TO ENVIRONMENTAL STRESS Abstract Mutation of the yxkO gene, which encodes a putative ribokinase and belongs to the σB general stress response regulon, leads to reduced salt tolerance under potassium limitation in Bacillus subtilis. The biological function of the yxkO gene has not been determined yet, but it may be involved in the high affinity potassium uptake system, which has been described in Escherichia coli in contrast to Bacillus subtilis. Our goal was to describe another features of a mutant in the yxkO gene and to try to propose the role of this gene. Using the integration vector pMutin4, we prepared a Bacillus subtilis strain MP2 with a yxkO gene inactivation. The MP2 strain displays limited growth in a rich medium and it is a sensitive strain to tetracycline. Furthermore, this strain is unable to form endospores and the cells are longer, which indicates a septum formation defect. We accomplished a 2-D protein gel analysis to compare expression profiles of the MP2 strain and the 1A680 standard strain after salt and ethanol stress. The MP2 strain shows changes in productions of some energy metabolism enzymes and flagellin protein. We conclude that yxkO is a regulatory gene, whose product has a pleiotropic effect on many of cell functions.

Homopolymers and copolymers produced from aromatic based methacrylates, acrylates, and dimethacrylates are excellent materials with many applications in dentistry, microelectronics, and optics, including optical eye wear, fiber optics, and non-linear optics, such as holography. Carbazole based polymers have demonstrated good optical, photo-refractive, and charge-transporting properties, combined with ease of processing. The objective of this research was to design, synthesize, and characterize high refractive index polymers and copolymers for use in optical spectacle lenses of eyeglasses. Additionally, other interesting attributes were observed for selected carbazole based polymers, such as high thermal stability and birefringence, which could lend these materials to other uses, such as non-linear optics and electronic data storage. A family of novel, high refractive index homopolymers and copolymers were synthesized by incorporating carbazole, along with other aromatic substituents, into methacrylates, acrylates, and dimethacrylates. Subsequent free radical polymerizations provided for high refractive index materials well suited for lightweight optical spectacles and other applications. The refractive index of materials can be increased by increasing the polarizability of substituent groups. By incorporating oxygen, sulfur, or sulfoxide groups into polymers, high refractive index polymers have been attained. By reacting the phenol, aromatic diols, or aromatic thiols with 9-(2,3-epoxypropyl)-carbazole, the refractive index of the final polymer can be increased further. The reaction of the carbazole based intermediate with methacryloyl chloride or methacrylic anhydride eliminated any hydroxyl groups in the final methacrylate or dimethacrylate. Hydroxyl groups undergo intermolecular hydrogen bonding, which increases viscosity. The absence of hydrogen bonding in the final methacrylated monomers reduces viscosity, which is desirable for processing. Novel carbazole based monomers and polymers were characterized in terms of molecular composition and molecular weight, thermal properties, such as melting point, glass transition temperature, and decomposition, and in terms of optical properties, such as refractive index. The AIBN initiated carbazole-phenoxy based methacrylate polymerization was followed using in-situ FTIR, which showed the reaction to be completed within 40 minutes in DMAC at 90°C. Photo-DSC was used to determine the heat of polymerization (DHp) for the carbazole-phenoxy based methacrylate, which was found to be -39.4 kJ/mole. One and two dimensional 1H NMR was used to characterize the molecular structure of the carbazole-phenoxy based methacrylate monomer. The carbazole-phenoxy based methacrylate homopolymer had a surprisingly high decomposition temperature. 13C NMR spectroscopy experiments and molecular modeling were employed to explore the configuration of the polymerized carbazole-phenoxy based methacrylate. The lack of head-to-head linkages due to steric considerations could explain the higher thermal stability observed for the carbazole-phenoxy based methacrylate polymer. Refractive indices of these carbazole based methacrylates, acrylates, and dimethacrylate polymers ranged from 1.53 to 1.63. Statistical copolymers of carbazole based methacrylates with methyl methacrylate were also produced by solution polymerization in DMAC, and characterized. Using free radical polymerization techniques, homopolymers and copolymers of the carbazole functionalized methacrylates, acrylates, and dimethacrylates were readily obtained. This research demonstrated a variety of carbazole based chemistries which could produce controlled linear and cross-linked materials with high refractive index values and other interesting features. / Ph. D.

Queueing theory is the mathematical study of queues or waiting lines, which are formed whenever demand for service exceeds the capacity to provide service. A queueing system is composed of customers, packets or calls that need some kind of service. These entities arrive at queueing system, join a queue if service is not immediately available and leave system after receiving service. There are also cases when customers, packets or calls leave system without joining queue or drop out without receiving service even after waiting for some time. Queueing network models with finite capacity have facilitated the analysis of discrete flow systems, such as computer systems, transportation networks, manufacturing systems and telecommunication networks, by providing powerful and realistic tools for performance evaluation and prediction. In wireless cellular systems mobility is the most important feature and continuous service is achieved by supporting handoff from one cell to another. Hand off is the process of changing channel associated with the current connection while a call is in progress. A handoff is required when a mobile terminal moves from one cell to another or the signal quality deteriorates in current cell. Since neighbouring cells use disjoint subset of frequency bands therefore negotiation must take place between mobile terminal, the current base station and next potential base station. A poorly designed handoff scheme significantly decreases quality of service (QOS). Different schemes have been devised and in these schemes handoff calls are prioritize. Also most of the performance evaluation techniques consider the case where the arrival process is poisson and service is exponential i.e. there is single arrival and single departure. Whereas in practice there is burstiness in cellular traffic i.e. there can be bulk arrivals and bulk departures. Other issue is that, assumptions made by stochastic process models are not satisfied. Most of the effort is concentrated on providing different interpretations of M/M queues rather than attempting to provide a new methodology. In this thesis performance evaluation of multi traffic cellular models i.e. non priority, priority and hand off calling scheme for bursty traffic are devised. Moreover extensions are carried out towards the analysis of a multi-traffic M/M queueing system and state probabilities are calculated analytically.

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