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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Millimeter-wave UWB architecture for wireless sensor networks

Ercoli, Mariano 14 December 2012 (has links) (PDF)
Exploiting wireless communications has had an unstoppable growth in the last years. In this attracting scenario, the Ultra Wide Band (UWB) market represents one of the main interesting targets for semiconductor industry. The availability of newer and larger bandwidth in the frequency spectrum (60 GHz and 77 GHz) opens to the possibility of higher bitrates communications. The technology cost reduction is made possible by the use of silicon as semiconductor substrate in the place of classical heterojunction materials. The rapid reduction of the technological node (seen as the thinning of the gate channel) in the new generation of CMOS transistors allows obtaining faster transistors that become usable on V band applications. Therefore, the digital origin of the technology yields two additional advantages. First of all, the facilities for the circuits' production already exist as well as the recipe to create the devices on the substrate. The only additive cost remains the characterization of the technology at mm-wave frequencies. The second fundamental advantage is the possibility to have a complete integration of the system in the same dies with a substantial reduction of packaging and interconnection costs. The objectives of this thesis is the design and the modeling of a complete 60 GHz UWB transceiver starting from the characterization and the optimization of the single subcomponents. The main feature that constitutes the principal constraint of the entire work of this thesis is the high efficiency required for the transceiver front - end. The energy safe capability, in fact, represents the strength point of this project, being the system conceived for wireless sensors network applications. Passive components as inductors and RF lines, have been the first elements that have been designed and characterized. Then the structure of CMOS transistor have been analyzed and characterized in order to obtain performances as higher as possible, in particular for wide transistors. The knowledge acquired during this first part has allowed the developed of high quality factor inductors and high performance transistors (used in the design of upconversion mixer). In addition, the optimum correspondence between simulations and measurements combined with the gained experience on the RF electromagnetic simulations have been exploited to create a series of innovative (when possible) passive structures as baluns, power splitters and power couplers. The second significant part of this work has been consecrated to the modeling of a series of high performance active circuits in the transmitter and the receiver blocks (upconversion mixer, voltage controlled oscillator ad a series of differential and single-ended buffers). The behavior of these structures has been accurately investigated and optimized in order to be later efficiently integrated in the complete transceiver system. The systems are finally integrated in two different dies, transmitter and receiver blocks, and the 60 GHz link has been yield by a demostrator set-up.
122

Pas de titre en français

Pandey, Amit Kumar 20 June 2012 (has links) (PDF)
Pas de résumés en français
123

Verification of real time properties in fiacre language

Abid, Nouha 11 December 2012 (has links) (PDF)
Pas de résumés en français
124

Vers le déploiement d'un réseau de capteurs enfouis dans des multi-plis carbone-epoxy pour l'instrumentation in-situ de structures composites pour l'avionique

Lubin, Jérôme 17 December 2012 (has links) (PDF)
Les matériaux composites à base de fibre carbone suscitent un intérêt grandissant dans l'industrie en général et avionique en particulier. Très appréciés pour leur résistance exceptionnelle aux efforts de traction ils présentent également un poids bien plus faible que les métaux y compris l'aluminium. Cela permet d'envisager la construction d'aéronefs d'une très grande solidité tout en réduisant significativement leur consommation en carburant. Cependant les composites carbone sont relativement fragiles sous des efforts en flexion ou compression. Leur durée de vie est peu connue et dépend fortement de la géométrie des pièces qui sont souvent surdimensionnées par sécurité. Afin de prévenir d'éventuels accidents et conserver des pièces légères il est indispensable d'évaluer leur état de santé. L'objectif de cette thèse est la conception d'une solution d'instrumentation à base de capteurs miniaturisés en technologie silicium sensibles aux vibrations mécaniques et capables de détecter l'apparition d'un défaut dans la structure. Nous développé un procédé de fabrication simple et robuste pour des capteurs dont l'élément sensible est une jonction PN de type Zéner implémentée dans du polysilicium. Nous avons démontré dans un premier temps une sensibilité aux vibrations mécaniques. La capacité de ces capteurs à faire du suivi de réticulation en autoclave a également été démontrée. La phase suivante a concerné l'étude d'un procédé de packaging souple robuste et modulable pour la mise en réseau des capteurs. Enfin la dernière étape concerne l'étude d'un circuit électronique permettant la lecture du signal et la réduction du bruit de fond.
125

New York, Pierpont Morgan Library, M. 333 and manuscript illumination at the monastery of St.-Bertin under Abbot Odbert (986-ca. 1007)

Lowry, Susan. January 1993 (has links)
Thesis (Ph. D.)--Columbia University, 1993. / Department: Art History. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 205-210).
126

Avaliação de Imunomarcação de COX-2 em Carcinomas Intestinais Caninos / Evaluation of cox-2 immunomarkation in canine intestinal carcinomas

Santos, Fernanda Faquim 07 May 2018 (has links)
Submitted by Fernanda Faquim Dos Santos (ferfachin@yahoo.com.br) on 2018-06-01T23:44:34Z No. of bitstreams: 1 DISSERTAÇÃO FERNANDA F.SANTOS.pdf: 1996897 bytes, checksum: 3f600e1895c2f870f15395cb5de30a1a (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-06-05T18:33:27Z (GMT) No. of bitstreams: 1 santos_ff_me_jabo.pdf: 1996897 bytes, checksum: 3f600e1895c2f870f15395cb5de30a1a (MD5) / Made available in DSpace on 2018-06-05T18:33:27Z (GMT). No. of bitstreams: 1 santos_ff_me_jabo.pdf: 1996897 bytes, checksum: 3f600e1895c2f870f15395cb5de30a1a (MD5) Previous issue date: 2018-05-07 / Devido ao aumento da expectativa de vida dos animais de estimação, o aparecimento de neoplasias tem se tornado uma importante afecção na Medicina Veterinária. As neoplasias gastrointestinais de cães são pouco diagnosticadas e sua etiologia é desconhecida. As localizações mais frequentes são o jejuno, cólon e reto. Objetivou-se avaliar a Cox-2 por meio de imunohistoquímica e a intensidade de PAS positivo nas amostras de intestinos de cães saudáveis (GS) e com neoplasia (GN). As neoplasias foram classificadas por análise histopatológica. As diferenças foram significativas quando P<0.05 (testes não paramétricos). Nas amostras neoplásicas observou-se imunodetecção acentuada de COX-2, quando comparadas aos cães saudáveis, com diferenças significativas entre os grupos. O mesmo ocorreu para a intensidade de PAS, onde se observou diminuição do número de células caliciformes e aumento na produção de muco nas amostras neoplásicas, enquanto nas amostras saudáveis observou-se marcação intensa nas células caliciformes. Com isso pode-se concluir que a COX está envolvida na capacidade do tumor evadir as defesas do sistema imunológico. Apesar da relação entre o processo inflamatório, mais especificamente o papel das prostaglandinas, e o desenvolvimento e propagação tumoral ser bastante claro, ainda muito se têm a ser esclarecido. / Due to the increase in the life expectancy of the pets, the appearance of neoplasias has become an important affection in the Veterinary Medicine. Gastrointestinal neoplasms of dogs are poorly diagnosed and their etiology is unknown. The most frequent locations are jejunum, colon and rectum. The objective of this study was to evaluate Cox-2 by means of immunohistochemistry and the positive PAS intensity in intestinal samples from healthy dogs (GS) and neoplasia (GN). The neoplasms were classified by histopathological analysis. The differences were significant when P <0.05 (non-parametric tests). In the neoplastic samples, marked COX-2 immunodetection was observed when compared to healthy dogs, with significant differences between groups. The same was observed for PAS intensity, where a decrease in the number of goblet cells and an increase in the mucus production were observed in the neoplastic samples, while in the healthy samples intense marking was observed in the goblet cells. With this we can conclude that COX is involved in the ability of the tumor to evade the defenses of the immune system. Although the relationship between the inflammatory process, more specifically the role of prostaglandins, and tumor development and propagation is very clear, much remains to be elucidated.
127

The role of arylamine N-acetyltransferase 1 (NAT1) in the clinical therapy of tuberculosis

Willemse, Gratia-Lize January 2017 (has links)
Magister Scientiae - MSc (Medical BioSciences) / Despite attempts to develop new drugs to reduce the worldwide mortality rate attributable to tuberculosis (TB), the illness remains a threat. Isoniazid (INH) has been used as a frontline drug for decades. However, several resistant strains of the organism - Mycobacterium tuberculosis (M. tuberculosis) - still emerge. The drug is mainly metabolised by a family of enzymes, arylamine N-acetyltransferases (NAT). The three human NAT genes - NAT1, NAT2 and the pseudogene, NATP - are found on chromosome 18p22. NAT1 and NAT2 are isoenzymes which differ at certain amino acid positions. Subsequently, the differences affect substrate specificity. NAT1 shows specificity to p-aminobenzoic acid (PABA) and paminosalicylate (PAS). Previously, computer algorithms were used to predict the efficacy of the enzyme with regard to the acetylation phenotype it confers. The two which were focused on, Sorting Intolerant From Tolerant (SIFT) program and Polymorphism phenotyping version 2 program (PolyPhen-2), showed conflicting results for the effect of SNPs on the acetylation rate and subsequent enzyme function. Further structural prediction methods were used to test the effect of V231G on the structure and consequent function of the native protein, NAT1.
128

Comprehension of complex animation : cueing, segmentation and 2D / 3D presentations / Comprehension d'animations complexes : signalisation, segmentation et présentations en 2D et 3D

Putri, Dian Kemala 25 November 2011 (has links)
Pas de résumé en français / The goal of our studies was to test the effect of segmentation, cueing, and 2D/3D presentations to foster complex animation rocessing. The material was an upright mechanical piano system. We used an eye tracking system which provides information about learners’ attention direction during the animation processing. We analyzed the effect of the format presentations and the eye movements during learning. Based on animation and multimedia research background, four experiments were conducted. In the first experiment the effect of the presentation of simplified external representations on learning from complex animation was investigated. Experiment two and three aimed at studying the cognitive processes involved in learning to complex mechanism system with new cueing techniques with spatial-temporal colored tokens. In the fourth experiment, 2D and 3D presentation of the same animated content were compared. Results of these experiments showed that (1) the use of a dual format presentation is better for developing a dynamic mental model from the animation than a single format, (2) the signaling strategies using cued tokens of dual format can guide efficiently learner’s building of mental model and can enhance learner’s comprehension of complex system, (3) a sequential format presentation followed by an animation format presentation helps the learner to understand the key stages of a dynamic process and to create a high quality mental model, (4) 3D animation presentation is better than 2D animation presentation to direct attention on relevant component of the animation. For depth processing, comprehension with 3D animation presentation is better than 2D animation format. Eye tracking measures provided insights into how people understood and learned complex systems. The analysis of eye tracking also contributed to the understanding of the subject’s perceptual processing during learning. Overall, results provide a significant contribution in the field of learning with complex animation. Recommendations in the ergonomics area for the design of animations are proposed.
129

Convergências entre o Programa de Avaliação Seriada da UnB e o ENEM na área de Matemática : histórico e perspectivas

Marques, André Marcelino 29 June 2016 (has links)
Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Matemática, Programa de Mestrado Profissional em Matemática em Rede Nacional, 2016. / Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2016-09-19T17:00:28Z No. of bitstreams: 1 2016_AndréMarcelinoMarques.pdf: 1280075 bytes, checksum: 2c6745927a4cc59860162a2d06a3c9d9 (MD5) / Approved for entry into archive by Raquel Viana(raquelviana@bce.unb.br) on 2016-10-13T17:20:07Z (GMT) No. of bitstreams: 1 2016_AndréMarcelinoMarques.pdf: 1280075 bytes, checksum: 2c6745927a4cc59860162a2d06a3c9d9 (MD5) / Made available in DSpace on 2016-10-13T17:20:07Z (GMT). No. of bitstreams: 1 2016_AndréMarcelinoMarques.pdf: 1280075 bytes, checksum: 2c6745927a4cc59860162a2d06a3c9d9 (MD5) / No Brasil, o acesso a um curso de graduação exige que o candidato se submeta a algum processo de seleção. Compreender os detalhes desse processo é fundamental para que ele obtenha êxito. Nesse cenário, o professor se insere como um orientador para seus alunos, devendo se apropriar de todas as informações para poder revelar a eles as características intrínsecas inerentes a esses processos de passagem da educação básica para a superior. Nesse sentido, este trabalho contribui como uma compilação dessas características, pois objetiva investigar as convergências entre o Programa de Avaliação Seriada da Universidade de Brasília (PAS/UnB) e o Exame Nacional do Ensino Médio (ENEM). Ambas as avaliações constituem importantes modalidades de acesso à Universidade de Brasília (UnB). O ENEM, de relevância nacional, tem o desempenho dos estudantes associado ao Sistema de Seleção Unificada (Sisu), o qual permite aos participantes optarem por ingressar em cursos de graduação na maioria das Instituições federais de ensino superior (IFES) do Brasil. A partir de 2017, o PAS será a modalidade de acesso à UnB que mais vinculará calouros à instituição. Para encontrar as convergências entre as duas avaliações, foi priorizada uma abordagem qualitativa, utilizando-se análises documental, de dados e de conteúdo. Iniciou-se com uma breve contextualização histórica, seguida de uma comparação das matrizes de referência que dão suporte teórico-metodológico aos dois processos, encontrando-se os pontos comuns referentes a competências, habilidades e objetos de conhecimento avaliados. O trabalho avançou para uma análise criteriosa dos itens das provas aplicadas no subprograma 2013-2015 do PAS/UnB e das questões da prova do ENEM de 2015, no âmbito da Matemática, destacando-se semelhanças e diferenças em termos da abordagem e dos objetivos avaliativos de cada item/questão. Nas perspectivas futuras, infere-se que a UnB fez a opção pelo fortalecimento do PAS como processo de escolha de seus estudantes ingressantes, apontando para uso mais eficaz da tecnologia associada ao Programa, com a implantação de provas adaptativas feitas em ambiente vistual. _________________________________________________________________________________________________ ABSTRACT / In Brazil, the access to anundergraduate course requires the candidate to undergo a selection process. Understanding the details of this process is essential for him to succeed. In this scenario, the teacher is included as a mentor for his students and it is expected that he gets all the information in order to reveal to them the intrinsic characteristics inherent in these processes of transition from basic to higher education. In this sense, this work contributes with a compilation of these characteristics, since it aims to investigate the convergences between the Programa de Avaliação Seriada from University of Brasilia (PAS/UnB) and the Exame Nacional do Ensino Médio (ENEM). Both examsare important ways of access the University of Brasilia (UnB). With national relevance, the ENEM has the performance of students associated with the Sistema de SeleçãoUnificada(SiSU), which allows participants to choose to join undergraduate courses in most public higher education institutions (IFES) in Brazil. From 2017, PAS will be the means of access to UnB that most freshmen bind the institution. To find the convergences between the two assessments forms, it was prioritized a qualitative approach, using documentary analysis, data and content. We start with a brief historical background, followed by a comparison of reference matrices that give theoretical and methodological support to the two exams, finding the commonalities regarding competences, abilities and knowledge objects. The work has progressed to a careful analysis of the mathematics items of the tests applied in the PAS/UnB - Subprogram 2013-2015 and in ENEMduring 2015, highlighting similarities and differences in terms of approach and evaluative goals of each item / question. In future prospects, it is inferred that the UnB has the option for strengthening the PAS as the process of choosing their freshmen students, pointing to more effective use of technology associated with the Program, with the implementation of adaptive tests made in a virtual environment.
130

La modernité ordinaire : Maurice Novarina, un architecte dans l'aventure des Trente Glorieuses / L'auteur n'a pas fourni de titre en anglais

Bonnot, Carine 03 November 2011 (has links)
Le projet de recherche présente un travail monographique sur l'architecte français Maurice Novarina, originaire de Haute-Savoie, qui a réalisé, tout au long du XXe siècle, d'importantes commandes publiques ; des églises – pour lesquelles il est le plus connu – et plus de 30 000 logements conçus lors des grandes opérations d'urbanisme des Trente Glorieuses. Son œuvre, répartie sur le territoire français et localisée majoritairement en Rhône-Alpes, en région parisienne et en Normandie, illustre l'évolution des commandes, des conceptions et des mises en œuvre architecturales et urbaines. Maurice Novarina fait partie des architectes qui ont marqué le XXe siècle par une production importante en quantité, et remarquée, hier comme aujourd'hui en qualité. En effet, nombreuses de ses réalisations sont considérées comme patrimoine puisqu'elles concernent certains monuments historiques, des bâtiments « Label XXe », ou intégrés dans des chartes patrimoniales et paysagères. Ce travail cherche donc à repositionner l'architecte dans l'histoire de l'architecture et de l'urbanisme du XXe siècle, à préciser le contexte politique, économique et social dans lequel sont nés les projets, et à questionner son œuvre en lumière des théories de la modernité. L'œuvre de Maurice Novarina reprend les caractéristiques architecturales et urbaines de la doctrine moderne : l'influence du compagnon de la modernité qu'est Auguste Perret est sensible dans les projets de reconstruction d'après-guerre, alors que celle de Le Corbusier et de la Charte d'Athènes irradie l'ensemble des projets d'urbanisme, plus particulièrement les ZUP. Ces modèles forts, les architectes les interprètent, les réduisent ou les améliorent. La production de Maurice Novarina, comme celle de nombreux de ses contemporains, concerne alors une architecture ordinaire, qui s'impose dans les réalisations du XXe siècle et se révèle omniprésente dans la presse architecturale de l'époque, alors qu'elle est finalement peu évoquée par l'Histoire. Ces architectures perdurent comme héritage du XXe siècle et résultent, non pas de la banalité, mais d'une forme d'application de la modernité corbuséenne, qui au-delà des grandes théories, a marqué les esprits et formaté notre regard contemporain. Partant de l'hypothèse que les principes architecturaux et urbains de la modernité peuvent prendre des formes de l'ordinaire, nous verrons comment, chez Maurice Novarina, l'architecture relie les deux entités contraires (modernité / ordinaire) et que le processus complexe d'élaboration des projets, reposant sur des associations d'acteurs, des commanditaires récurrents et des équipes pluridisciplinaires, participent également à la richesse des œuvres. / L'auteur n'a pas fourni de résumé en anglais.

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