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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.
11

Signal Transmission in Escherichia coli Cyclic AMP Receptor Protein for Survival in Extreme Acidic Conditions

Evangelista, Wilfredo, Knapp, James, Zandarashvili, Levani, Esadze, Alexandre, White, Mark A., Gribenko, Alexey V., Lee, J. Ching 12 October 2021 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / During the life cycle of enteric bacterium Escherichia coli, it encounters a wide spectrum of pH changes. The asymmetric dimer of the cAMP receptor protein, CRP, plays a key role in regulating the expressions of genes and the survival of E. coli. To elucidate the pH effects on the mechanism of signal transmission, we present a combination of results derived from ITC, crystallography, and computation. CRP responds to a pH change by inducing a differential effect on the affinity for the binding events to the two cAMP molecules, ensuing in a reversible conversion between positive and negative cooperativity at high and low pH, respectively. The structures of four crystals at pH ranging from 7.8 to 6.5 show that CRP responds by inducing a differential effect on the structures of the two subunits, particularly in the DNA binding domain. Employing the COREX/BEST algorithm, computational analysis shows the change in the stability of residues at each pH. The change in residue stability alters the connectivity between residues including those in cAMP and DNA binding sites. Consequently, the differential impact on the topology of the connectivity surface among residues in adjacent subunits is the main reason for differential change in affinity; that is, the pH-induced differential change in residue stability is the biothermodynamic basis for the change in allosteric behavior. Furthermore, the structural asymmetry of this homodimer amplifies the differential impact of any perturbations. Hence, these results demonstrate that the combination of these approaches can provide insights into the underlying mechanism of an apparent complex allostery signal and transmission in CRP. / National Institutes of Health / Revisión por pares
12

Isolement acoustique de parois aux basses fréquences : programmation d'outils prédictifs et confrontations expérimentales dans le cas de planchers solivés en bois / Sound insulation of walls at low frequencies : programming predictive tools and experimental results in the case of timber joist floor

Tribaleau, Antonin 24 September 2013 (has links)
Dans le domaine de l’acoustique du bâtiment, la structuredes constructions en bois est légère et ses capacités d’isolementacoustique sont faibles en particulier pour les basses fréquencesen comparaison à d’autres techniques de constructioncomme le béton. Les travaux de cette thèse se donc sont centréssur l’élaboration d’un outil prédictif visant à déterminer lesperformances acoustiques des planchers solivés en bois afin decompléter les outils prédictifs actuellement sur le marché. Laméthode des éléments finis est adaptée pour résoudre ce problèmevibro-acoustique car le comportement basses fréquencesest de type modal. Pour gagner en temps de calcul, une résolutionmixte éléments finis – formulation intégrale d’Huygens etdifférentes optimisations ont été mises en place. Grâce à l’utilisationde la méthode des éléments finis, il a été possible demettre en évidence des résonances de ce problème couplé quifont chuter localement la valeur de l’affaiblissement ; celles-cine peuvent être prises en compte par la méthode des matricesde transfert. Néanmoins, ces deux méthodes fournissent des alluresmoyennes de courbes d’affaiblissement équivalentes, enparticulier lors d’une étude en tiers d’octave. Pour aborder leproblème des transmissions latérales, nous avons montré lafaisabilité de la détermination expérimentale des propriétés mécaniqueséquivalentes d’un élément de jonction courant entreles planchers et les murs : le sabot métallique. Un modèle mécaniquesimplifié par éléments finis permet ainsi un couplagemécanique entre les solives et les poutres en intégrant les effetslocaux de dissipation présents pour ce type de jonction. / In building acoustics, the structure of wooden construction islightweight and sound insulation at low frequency are weakcompared to other construction techniques like concrete. Thework of this thesis is focus on the development of predictivetools for determining the acoustic performance of wooden joistfloors to complete the existing predictive tools available on themarket. The finite element method (FEM) is adapted to solvethis vibro-acoustic problem because behavior at low frequenciesis modal. To save computation time, a mixed resolutionfinite element with Huygens integral formulations and severaloptimizations were implemented. We could note the interest ofthe FEM : we observed that resonances of the coupled systemdrive locally down the value of the TL, which can not be takeninto account by the method of transfer matrices. However, wenote that these two methods provide equivalent average curveshapes of TL’s spectrum. To deal with the problem of flankingtransmissions, penalizing the lightweight construction, we experimentalydetermine the mechanical properties of a equivalentjunction element between floors and walls : the wood joisthanger. Through a simplified mechanical model, this numericalfinite element model allows a mechanical coupling between thejoists and beams by incorporating the local effects of dissipationpresent for this type of junction.
13

Les règles de droit patrimonial et successoral à la Basse Epoque égyptienne et à l'époque ptolémaïque (664 - 30 avant notre ère) / The rules of patrimonial and inheritance rights in Egypt during the late period and the Ptolemaïc period (660-30 B. C.)

Houssais, Frédéric 19 June 2013 (has links)
Les présents travaux portent sur une période particulière de l’Égypte pharaonique, marquée par l’apparition d’une nouvelle écriture cursive – le démotique – transcrivant un état plus récent de la langue égyptienne, et par une évolution marquée de la société égyptienne sous l’influence des dominations étrangères successives. Parmi la documentation juridique disponible, de nombreux textes ont trait aux règles de droit patrimonial et à leurs modes de transmission : des textes théoriques ( tel le Code d’Hermopolis), mais également, et en plus grands nombres, de la documentation d’application de ces règles de droit et des décisions judiciaires s’y rapportant, ainsi que des textes littéraires qui nous éclairent sur le mode de fonctionnement de la famille égyptienne du premier millénaire avant notre ère. Outre la description des règles de transmission patrimoniale intrafamiliale, l’analyse de cette documentation permet de percevoir le rôle des différents éléments composant la famille égyptienne : père, fils aîné, femme, principalement, et d’en mieux comprendre les mécanismes successoraux en tant que vecteur, non seulement du patrimoine familial, mais aussi et surtout, du rôle de chef de famille, de patriarche, au sein de l’indivision familiale. Enfin, les sources juridiques relevant de la pratique démontrent que les Égyptiens du premier millénaire avant notre ère interprétaient les règles liées aux transmissions patrimoniales et en usaient de façon stratégique, afin de les façonner de la manière désirée, quitte à passer outre aux principes établis, parfois depuis de nombreux siècles. / The present work concerns a particular period of Pharaonic Egypt, marked by the appearance of a new cursive writing – the demotic writing – transcribing a more recent state of the Egyptian language, and a loss of political independence. Among the available legal documentation, numerous texts concerned the rules of patrimonial law and their modes of transmission: theoretical texts (such as the Legal Code of Hermopolis), but also, and in larger numbers, the application documentation of these legal rules and the court orders relating to it, and literary texts which give us another view of the first millennium B.C. Egyptian family way of functioning. Besides the description of the rules of the family intra family holdings transmission, the analysis of this documentation allows to determine what the role of the family main component was: father, first son, woman, and to understand the inheritance process as vector, not only of the family goods, but mostly of the family chief (or patriarch) role in the family undivided possession. Then, the useful judicial sources show that the first millennium B.C. Egyptians interpreted the rules of patrimonial transmissions and used of them strategically in order to disregard the established principles, often since centuries
14

Influence des jonctions sur le comportement vibro-acoustique d'assemblages de structures bois pour le bâtiment / Influence of the junctions on the vibro-acoustic behaviour of wooden lightweight structures

Blon, David 28 September 2016 (has links)
La forte sensibilité des ouvrages bois aux transmissions latérales, vibrations et autres sons basses fréquences représente un obstacle à leur développement. En réponse à cette problématique, le projet Vibracoubois, dans lequel s'inscrivent ces travaux, vise à développer la caractérisation ainsi que la modélisation des transferts vibro-acoustiques au sein de ces structures. L'objectif principal de ces travaux est donc d'élargir le champ de l'étude expérimentale et numérique à une structure complète constituée de différentes parois et de cavités couplées. Les jonctions, véritables nœuds des systèmes constructifs, sont placées au centre de l'étude. Pour ce faire, un protocole expérimental est développé, permettant d'effectuer des mesures en laboratoire mais également in-situ sur des structures réelles. Les résultats de campagnes d'essais effectuées au sein de deux maquettes d'ouvrages bois (ossature et bois massif) grandeur nature sont présentés. Par ailleurs, en vue de se rapprocher des jonctions réelles du bâtiment, des méthodes numériques de couplage incluant des effets locaux de dissipation sont développées. Une méthode hybride est présentée. Un modèle numérique de la maquette en bois massif, basé sur la méthode des éléments-finis, est créé. L'utilisation de cette méthode est justifiée de par la prépondérance des comportements modaux aux basses fréquences. Ce modèle intègre la méthode hybride en vue d'obtenir un couplage souple entre les parois, par opposition au couplage classique rigide des éléments-finis. Les résultats d'un processus de recalage portant sur les propriétés des parois et des jonctions ainsi que sur le couplage vibro-acoustique sont présentés. / Wooden buildings are very sensitive to flanking transmissions, vibrations and low frequency sounds, which interferes with their development. The Vibracoubois project, in which this research work is part of, aims to respond to this problem by improving the vibro-acoustic transfers characterization and modelling of these structures. This research work mainly focuses on expanding the experimental and the numerical scope of the study to an entire structure made of coupled walls and air cavities. The junctions, considered critical for the vibration propagation in these buildings, are placed at the center of this work. First, an experimental protocol is presented. It allows to measure both the vibro-acoustic behaviour of laboratory and real structures. The results of test campaigns run on two full-scale experimental mock-ups (timber frame and CLT) are then presented. Secondly, numerical coupling methods that include local dissipation effects are developed, in order to get closer to real junctions behaviour. A hybrid coupling method is presented. A numerical model of the CLT mock-up, based on the finite-elements method, is then created. The use of this method is justified because of the strong modal behaviour of these structures at low frequencies. This model implements the hybrid coupling method in order to create flexible junctions, as opposed to the classic rigid coupling of the finite-elements. Based on the CLT mock-up experimental measurements, the results of an adjustment process of the wall and the junction properties used in the numerical model is finally presented.
15

Exploitation de la non-circularité pour les transmissions et l'écoute passive / Exploitation of non-circularity for transmissions and passive listening

Sadok, Mustapha 15 December 2017 (has links)
Cette thèse est consacrée à l’exploitation des propriétés de non-circularité et de non-gaussianité des signaux d’intérêt (SOI) et/ou des interférences pour les transmissions sans fil et l’écoute passive. Dans une première partie de cette thèse, nous nous intéressons à l’extension des récepteurs SIMO-MLSE conventionnels vers de nouvelles architectures exploitant la potentielle non-circularité au second ordre des interférences co-canal (CCI), pour la démodulation de signaux rectilignes (BPSK, ASK), quasi-rectilignes (MSK, GMSK et OQAM) et à symboles complexes (QAM). L’architecture générale des récepteurs développés est basée sur un prétraitement avec une extension widely linear (WL) du filtre adapté spatio-temporel, ramenant le traitement de démodulation à un problème scalaire, un échantillonnage au rythme symbole et ensuite un organe de décision basé sur une version modifiée de l’algorithme de Viterbi. Pour le cas particulier des signaux quasi-rectiligne, on intercale un traitement de dérotation entre l’échantillonneur et l’organe de décision. Un travail de modélisation à temps discret des SOI, brouilleurs et du bruit de fond a été mené afin de créer des modèles de simulations pour la validation des expressions SINR analytiques interprétables, via l’évaluation des probabilités d’erreur symboles. Dans une deuxième partie, nous nous intéressons à la formation de voies (Beamforming) non-linéaire à travers des structures de Volterra complexe du troisième ordre. Ces dernières permettent l’exploitation de la non-circularité jusqu’au sixième ordre ainsi que du caractère non-gaussien des SOI et/ou des interférences. Dans le contexte de l’écoute passive, nous avons introduit un beamformer MVDR de Volterra du troisième ordre utilisant la seule information a priori du vecteur directionnel du SOI et implémentable grâce à une structure équivalente GSC. Nous avons étudié ses performances en particulier par l’évaluation analytique des expressions du SINR en fonction des statistiques de l’interférence, et par sa vitesse d’apprentissage, démontrant ainsi sa supériorité par rapport aux beamformers MVDR linéaire et WL classiques. Dans un contexte de radiocommunications, nous avons étudié une version MMSE de ce beamformer de Volterra complexe du troisième ordre qui prend lui en compte les propriétés statistiques de non-circularité jusqu’au sixième ordre et de non-gaussianité du SOI et du CCI. La dernière partie de cette thèse est consacrée à la robustesse de tests de détection de rectilinéarité de signaux en présente d’offsets de fréquence. Ces tests sont importants pour ajuster la nature du traitement (linéaire ou WL) en fonction de la rectilinéarité des signaux, afin de garantir le meilleur rapport performance/temps de convergence des algorithmes / This thesis is devoted to exploit the non-circularity and non-gaussianity properties of signals of interest (SOI) and/or interference for wireless transmissions and passive listening. In the first part of this thesis, we are interested in the extension of conventional SIMO-MLSE receivers to new architectures exploiting the potential second order non-circularity of co-channel interference (CCI), for the demodulation of rectilinear signals (BPSK, ASK), quasi-rectilinear (MSK, GMSK and OQAM) and quadrature amplitude modulation (QAM). The general architecture of the developed receivers is based on a pre-processing with a widely linear (WL) extension of the spatio-temporal matched filter, bringing the demodulation processing back to a scalar problem, a sampling at the symbol rate and then a decision block based on a modified version of the Viterbi algorithm. For the particular case of the quasi-rectilinear signals, a derotation processing is interposed between the sampler and the decision block. A work on equivalent discrete time modeling of SOI, interferers and background noise has been carried out in order to create simulation models as for the validation of the interpretable analytic SINR expressions, by the evaluation of the symbol error rates. In a second part, we are interested to the beamforming through complex Volterra structures of the third order. These structures allow us the exploitation of the non-circularity up to the sixth order as well as the non-gaussian nature of the SOI and/or the interferences. For passive listening applications, we have introduced a third-order Volterra MVDR beamformer using only a priori information of SOI steering vector and implemented by an equivalent GSC structure. We have studied its performance, in particular by interpretable closed-form expressions as functions of statistics of the interference, and by its speed of learning, thus proving its advantages with respect to the conventional linear and WL MVDR beamformers. For wireless communications applications, we have studied an MMSE version of this complex Volterra beamformer of the third order that takes into account of the non-circularity up to the sixth order as well as the non-gaussian nature of the SOI and interference. The last part of this thesis is devoted to the robustness of rectilinearity tests in the presence of frequency offset. These tests are important for adjusting the processing (linear or WL) as a function of the rectilinearity of the signals in order to guarantee the best performance/convergence rate ratio of algorithms
16

DATA COMMUNICATIONS OVER AIRCRAFT POWER LINES

Tian, Hai, Trojak, Tom, Jones, Charles 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper introduces a study of the feasibility and initial hardware design for transmitting data over aircraft power lines. The intent of this design is to significantly reduce the wiring in the aircraft instrumentation system. The potential usages of this technology include Common Airborne Instrumentation System (CAIS) or clock distribution. Aircraft power lines channel characteristics are presented and Orthogonal Frequency Division Multiplexing (OFDM) is introduced as an attractive modulation scheme for high-speed power line transmission. A design of a full-duplex transceiver with accurate frequency planning is then discussed. A general discussion of what communications protocols are appropriate for this technology is also provided.
17

Characterisation of the agent strain in sporadic and variant Creutzfeldt-Jakob disease by transmission to wild-type mice

Ritchie, Diane Louise January 2012 (has links)
Transmissible spongiform encephalopathy (TSE) strains are defined by their biological properties on transmission to wild-type mice, specifically by their characteristic incubation periods and patterns of vacuolar pathology (‘lesion profiles’) in the brain. Whilst a single TSE strain has been identified in variant Creutzfeldt-Jakob disease (vCJD), the phenotypic heterogeneity observed in sporadic CJD (sCJD) implies the existence of multiple strains of agent. These distinct strains are proposed to be enciphered by the different conformers of abnormal prion protein (PrP), recognised as different protease resistant PrP (PrPres) types by Western blotting (type 1 or type 2) and are thought to be substantially influenced by the different prion protein gene (PRNP) codon 129 polymorphism (MM, MV and VV). To test the relationship between disease phenotype and agent strain, this study carried out a full characterisation of the sCJD agent by primary transmission of brain tissue from 27 sCJD cases (comprising all six possible combinations of PRNP codon 129 genotype and PrPres type) in panels of wild-type mice using the standard strain typing properties of incubation period and lesion profiles, plus a full analysis of PrP in the mouse brain and the PrPres molecular subtypes present. Results were directly compared with the transmission characteristics of brain tissue from 10 vCJD cases. The characterisation of the agent strain in sCJD and vCJD was extended to include analysis of subsequent mouse-to-mouse passages. In an additional investigation, wild-type mice were experimentally challenged with a wide-range of lymphoid tissues, neural tissues and biological fluids from vCJD and sCJD patients in order to investigate the extent of peripheral involvement in CJD and to determine whether the agent is subject to any tissue-specific modifications. Analysis of all 27 sCJD sources demonstrated the existence of two strains of agent, one associated with the MM1/MV1 subgroups and the other associated with the MM2 subgroup, which could be distinguished by their transmission properties in the mice. The lack of transmission in mice challenged with VV1, MV2 and VV2 tissues provided evidence of at least one further sCJD strain. In contrast, all 10 vCJD sources resulted in consistent incubation periods and lesion profiles, suggesting that all 10 patients investigated were infected with the same strain of agent. Overall, the observation that PrPres type in sCJD and vCJD was maintained on transmission is consistent with the proposition that PrPres type plays a role in enciphering strain-specific information. Experimental transmissions from peripheral tissues extended the evidence for a peripheral infection in vCJD. However, comparison of incubation periods and lesion profiles from transmission of brain and peripheral tissues showed no evidence of tissue-specific modification in the biological properties of the agent. Furthermore, the detection of low levels of infectivity in a sCJD buffy coat sample provides supporting evidence for a peripheral involvement in sCJD. This study highlights the complex relationship between disease phenotype, PRNP codon 129 genotype, PrPres type and agent strain in sCJD and vCJD. Overall, this study confirms that multiple strains of agent are associated with sCJD, some of which successfully propagate in wild-type mice but none of which are identical to the agent responsible for vCJD. Importantly, the sCJD strains identified here by their biological properties partially correlated with the current sub-classification system for sCJD which is based on the clinical and pathological phenotype of the disease.
18

Eficiência de uma transmissão automotiva e do comportamento tribológico em regimes de lubrificação aplicados à engrenagens automotivas. / Efficiency at automotive transmission and tribology behavior at lubrification conditions applied at automotive gears.

Machado, Guilherme Antonio Assis 28 August 2018 (has links)
O aumento de eficiência de transmissões automotivas é a grande motivação deste trabalho. Sendo um dos objetivos principais avaliar correlações entre ensaios de eficiência de transmissões (com foco em engrenagens e cinemática do engrenamento) e ensaios tribológicos (com foco na avaliação do coeficiente de atrito e regimes de lubrificação). Nos ensaios tribológicos foi determinado o coeficiente de atrito para diferentes relações de rolamento e deslizamento, regimes de lubrificação, lubrificantes e recobrimentos. No banco de testes de transmissões automotivas foram avaliados diferentes lubrificantes e recobrimentos, similares aos avaliados nos ensaios tribológicos. Para se estabelecer a correlação entre estas duas escalas de ensaios, foi feito primeiramente um mapeamento de esforços e combinação de velocidades de rolamento e deslizamento durante o contato entre os dentes em uma transmissão. Este mapeamento permitiu: 1) que ensaios tribológicos tipo rolo esférico-disco fossem realizados de forma a se obter os coeficientes de atrito em diversas relações de razão deslizamento-rolamento (SRR - \"slide to roll ratio\") de forma a avaliar a performance de um revestimento a base de carbono e um óleo lubrificante aditivado; 2) Ensaios tribológicos esfera-disco plano também fossem realizados de forma a levantar os coeficientes de atrito para que, neste caso, fosse feito um confronto de especificação de óleos. Os ensaios de banco de provas foram feitos em diferentes condições: 1) utilizando um automóvel; 2) simulações numéricas (softwares comerciais) e 3) utilizando um banco para avaliação de eficiência de transmissões (dinamômetros e motores elétricos). Tanto os ensaios tribológicos (coeficiente de atrito) como testes de banco (avaliação da eficiência da transmissão) foram conduzidos em diferentes cenários de temperatura, relações de pressão de contato e velocidade comparadas com uma configuração de referência (características superficiais da engrenagem, contato na engrenagem e regimes de lubrificação). Os resultados obtidos permitiram associar o mapeamento do contato entre engrenagens e o regime de lubrificação com as eficiências obtida em banco de transmissões, softwares e ensaios tribológicos. Estes resultados indicam menores custos em desenvolvimentos e projetos de transmissões automotivas. / The greatest motivation of this thesis was the improving the efficiency of automotive transmissions. One of the aspects studied is how to establish a correlation between tribological test parameters based on the friction coefficient and lubrication regimes to the efficiency of an automotive transmission bench test. The efficiency of the transmission based on the contact established during the gearing for different coatings and lubricants. This correlation was based primarily using a stress map and the combination of sliding and rolling speeds applied on the surface contact between gear teeth. This mapping allows testing: 1) tribolological tests (roll on disc) combined with a device used to simulate contact conditions on friction coefficient, in which different conditions of slide to roll ratio (SRR) were obtained. Therefore the effect of carbon base coating and lubricants with different features could be tested. 2) tribological tests (ball on disc), in which friction coefficient was obtained for different lubricants to evaluate the behavior of them, probably related to additives. Transmission bench tests were also conducted, transmissions were tested:1) in automobiles; 2) using numerical simulation; 3) rig tests (dynamometers and electrical engines). Bench tests evaluated primarily the efficiency of the transmission. Tests (tribological and bench tests) in various scenarios of temperature, contact pressure ratio and speeds compared to the reference configuration (surface features of transmission gears, gear contact and regimes of lubrication) allowed the comparison between transmission efficiency, regimes the lubrication obtained during bench tests and tribological parameters, such as friction coefficient, and therefore, the results can help in selecting coatings and lubricants. These results indicate lower development and design costs in transmissions evaluation can be reached.
19

O PROCESSO DE PARENTALIZAÇÃO E SEUS ATUAIS IMPASSES.

Bandiera, Gisele Teles da Cruz 25 March 2015 (has links)
Submitted by admin tede (tede@pucgoias.edu.br) on 2016-08-18T11:45:21Z No. of bitstreams: 1 GISELE TELES DA CRUZ BANDIERA.pdf: 891371 bytes, checksum: a12223dc7729e7f755c2f4f66179e0f2 (MD5) / Made available in DSpace on 2016-08-18T11:45:21Z (GMT). No. of bitstreams: 1 GISELE TELES DA CRUZ BANDIERA.pdf: 891371 bytes, checksum: a12223dc7729e7f755c2f4f66179e0f2 (MD5) Previous issue date: 2015-03-25 / This study aims to understand the complexity and the richness of the elements that come together for the construction of parenthood, from the psychoanalytic theory approach, using the descriptive method of Interpretative Phenomenological Analysis (IPA) and, above all, a case study. The results highlighted the psychic level, the importance of primary narcissism, the psychic transmissions that goes through the generations, and the reminiscence of childhood history of the parents. In a historical, social and cultural level, were evidenced impasses resulting from the breakdown of traditional paradigms – haunting contradictions and uncertainties – and still the individualistic logic and prevailing hedonistic. This context led to profound upheavals in the structure and family functioning, marked by the change in mindset of parents and of the postmodern woman, by the inversion of roles and the consequent imbalance of parental investment. Finally, highlighted that parents sufficiently good ensure a space of transcription and transformation to their heir, thanks to their psychological resources able to face adequately the needs of the environment and pull away themselves both of the compulsory repetition of transgenerational purposes as of the illusory attempt of refuse them. Therefore, it is a process that began in its own early childhood where certainly had been granted a satisfactory maternal care. Otherwise, still remain to parents, to find in the relation with child, a shelter to such repairs. / Este trabalho objetiva compreender, a partir das manifestações e relatos da experiência parental, a complexidade e a riqueza dos elementos que se conjugam para a construção da parentalidade e os atuais impasses envolvidos nesse processo. Trata-se de uma pesquisa qualitativa, composta de um estudo de caso, que adota a entrevista como instrumento para coleta de dados e a Análise Fenomenológica Interpretativa (AFI) como método para descrever e interpretar o fenômeno da parentalidade. Os resultados obtidos ressaltaram a importância do narcisismo primário, das transmissões psíquicas que perpassam as gerações, e da reminiscência da própria história infantil dos pais. Evidenciou impasses em função da quebra dos paradigmas tradicionais – que assombrou contradições e incertezas – e da lógica individualista e hedonista predominante. Esse contexto provocou reviravoltas profundas na estrutura e no funcionamento familiar, marcadas pela mudança no ideário dos pais e da mulher pós-moderna, pela inversão dos papéis e o consequente desequilíbrio do investimento parental. Por fim, a pesquisa destacou que pais suficientemente bons asseguram um espaço de transcrição e transformação ao seu herdeiro, graças aos seus recursos psíquicos capazes de enfrentar adequadamente às exigências do meio e de se desvencilharem, tanto da repetição compulsória dos desígnios transgeracionais, quanto da ilusória tentativa de recusá-los. Para tanto, conta-se com um processo iniciado em sua tenra infância, na qual, certamente, garantiuse uma assistência materna satisfatória. Caso contrário, ainda lhes resta encontrar, na própria relação vincular com o filho, abrigo para tais reparações.
20

Contribution à l'ingénierie des systèmes de transmission terrestres sur fibre optique utilisant le multiplexage en longueur d'onde de canaux modulés au débit de 40 Gbit/s.

Frignac, Yann 04 1900 (has links) (PDF)
Dans le contexte de l'expansion de la téléphonie mobile et de l'Internet de l'année 2000, la conception de systèmes de transmission numériques sur fibre optique atteignant des capacités de l'ordre du terabit/s est envisagée par les équipementiers. Ce travail de thèse contribue à répondre à ce défi technologique, dans le cadre des systèmes terrestres utilisant la technique du multiplexage en longueur d'onde (WDM). Les solutions explorées consistent, premièrement en l'évolution du débit par canal de 10 Gbit/s à 40 Gbit/s puis en l'augmentation de la capacité d'information transmise par unité de bande passante optique jusqu'à 1.28 bit.s-1Hz-1. Les adaptations des systèmes sont préalablement analysées par simulations numériques offrant des règles d'ingénierie et des idées nouvelles puis les résultats de ces analyses sont concrétisés par des expériences de transmission démonstratives allant jusqu'à un multiplexage de 256 canaux à 40 Gbit/s soit une capacité totale de 10 Tbit/s.

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