Thèses sur le sujet « Normal observer »

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1

Falkenberg, Helle Kristine. « An ideal observer approach to development of motion perception in normal and abnormal vision ». Thesis, Glasgow Caledonian University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416577.

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Bernard, Pauline. « Synthèse d'observateur pour systèmes non linéaires ». Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLEM010/document.

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Contrairement aux systèmes linéaires, il n’existe pas de méthode systématique pour la synthèse d’observateurs pour systèmes non linéaires. Cependant, la synthèse peut être plus ou moins simple suivant les coordonnées choisies pour exprimer la dynamique. Des structures particulières, appelées formes canoniques, ont notamment été identifiées comme permettant la construction facile et directe d’un observateur. Une façon usuelle de résoudre ce problème consiste donc à chercher un changement de coordonnées réversible transformant l’expression de la dynamique dans l’une de ces formes canoniques, puis à synthétiser l’observateur dans ces coordonnées, et enfin à en déduire une estimation de l’état du système dans les coordonnées initiales par inversion de la transformation. Cette thèse contribue à chacune de ces trois étapes. Premièrement, nous montrons l’intérêt d’une nouvelle forme triangulaire avec des non linéarités continues (non Lipschitz). En effet, les systèmes observables pour toutes entrées, mais dont l'ordre d’observabilité différentielle est supérieur à la dimension du système, peuvent ne pas être transformables dans la forme triangulaire Lipschitz standard, mais plutôt dans une forme triangulaire "seulement continue". Le célèbre observateur grand gain n’est alors plus suffisant, et nous proposons d’utiliser plutôt des observateurs homogènes.Une autre forme canonique intéressante est la forme linéaire Hurwitz, qui admet un observateur trivial. La question de la transformation d’un système non linéaire dans une telle forme n’a été étudiée que pour les systèmes autonomes à travers les observateurs de Kazantzis-Kravaris ou de Luenberger. Nous montrons ici comment cette synthèse, consistant à résoudre une EDP, peut être étendue aux systèmes instationnaires/commandés. Quant à l’inversion de la transformation, cette étape est loin d’être triviale en pratique, surtout lorsque les espaces de départ et d’arrivée ont des dimensions différentes. En l’absence d’expression explicite et globale de l’inverse, l’inversion numérique repose souvent sur la résolution d’un problème de minimisation couteux en calcul. C’est pourquoi nous développons une méthode qui permet d’éviter l’inversion explicite de la transformation en ramenant la dynamique de l’observateur (exprimée dans les coordonnées de la forme canonique) dans les coordonnées initiales du système. Ceci passe par l’ajout de nouvelles coordonnées et par l’augmentation d’une immersion injective en un difféomorphisme surjectif. Enfin, dans une partie totalement indépendante, nous proposons aussi des résultats concernant l’estimation de la position du rotor d’un moteur synchrone à aimant permanent en l’absence d’informations mécaniques (sensorless) et lorsque des paramètres tels que la résistance ou le flux de l’aimant sont inconnus. Ceci est illustré par des simulations sur données réelles
Unlike for linear systems, no systematic method exists for the design of observers for nonlinear systems. However, observer design may be more or less straightforward depending on the coordinates we choose to express the system dynamics. In particular, some specific structures, called canonical forms, have been identified for allowing a direct and easier observer construction. It follows that a common way of addressing the problem consists in looking for a reversible change of coordinates transforming the exression of the system dynamics into one of those canonical forms, design an observer in those coordinates, and finally deduce an estimate of the system state in the initial coordinates via inversion of the transformation. This thesis contributes to each of those three steps.First, we show the interest of a new triangular canonical form with continuous (non-Lipschitz) nonlinearities. Indeed, we have noticed that systems which are observable for any input but with an order of differential observability larger than the system dimension, may not be transformable into the standard Lipschitz triangular form, but rather into an "only continuous" triangular form. In this case, the famous high gain observer no longer is sufficient, and we propose to use homogeneous observers instead.Another canonical form of interest is the Hurwitz linear form which admits a trivial observer. The question of transforming a nonlinear system into such a form has only been addressed for autonomous systems with the so-called Lunberger or Kazantzis-Kravaris observers. This design consists in solving a PDE and we show here how it can be extended to time-varying/controlled systems.As for the inversion of the transformation, this step is far from trivial in practice, in particular when the domain and image spaces have different dimensions. When no explicit expression for a global inverse is available, numerical inversion usually relies on the resolution of a minimization problem with a heavy computational cost. That is why we develop a method to avoid the explicit inversion of the transformation by bringing the observer dynamics (expressed in the canonical form coordinates) back into the initial system coordinates. This is done by dynamic extension, i-e by adding some new coordinates to the system and augmenting an injective immersion into a surjective diffeomorphism.Finally, in a totally independent part, we also provide some results concerning the estimation of the rotor position of a permanent magnet synchronous motors without mechanical information (sensorless) and when some parameters such as the magnet flux or the resistance are unknown. We illustrate this with simulations on real data
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Jakobsson, Tell. « Lactobacillus iners and the normal vaginal flora ». Doctoral thesis, Linköping : Department of Clinical and Experimental Medicine, Linköping University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11334.

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4

Léonard, Guillaume. « Observer pour agir : Une étude comparative de la facilitation motrice liée à l'observation, l'imagerie et l'imitation d'actions dans le vieillissement normal et la maladie de Parkinson ». Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27265.

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L'objectif du présent travail était de déterminer et de comparer le patron de modulation de l'excitabilité corticomotrice lié à l'observation, l'imagerie et l'imitation d'actions chez les jeunes âges de moins de 30 ans (n=21), les personnes âgées de plus de 55 ans (n=19) et les personnes atteintes de la maladie de Parkinson (MP) (n=11). L'action présentée sur un écran d'ordinateur 17" illustrait la main d'une personne coupant une pièce de matériel à l'aide d'une paire de ciseaux. Les potentiels moteurs évoqués induits à l'aide de la stimulation magnétique transcrânienne étaient mesurés dans le premier interosseux dorsal (FDI) et dans le court abducteur du cinquième doigt (ADM) dans quatre conditions: (1) repos, (2) observation de l'action, (3) imagerie motrice de l'action et (4) imitation de l'action. Chez les jeunes participants, l'imitation produisait la plus grande facilitation lorsque comparée au repos, suivi de l'observation et de l'imagerie qui induisaient des facilitations comparables. Ces facilitations étaient sélectives au muscle FDI puisque, dans le muscle ADM, seule l'imitation était associée à une facilitation corticomotrice. Chez les personnes âgées, le patron de facilitations était relativement semblable à celui observé chez les jeunes, à la différence que les facilitations notées dans le FDI étaient aussi présentes dans l'ADM. Quant aux patients avec la MP, les facilitations associées aux conditions d'observation et d'imagerie se sont avérées variables et inconsistantes par rapport aux personnes contrôlés du même âge. La diminution de la sélectivité chez les personnes âgées ainsi que les déficits des facilitations clicz les personnes atteintes de la MP cadrent bien avec la théorie de simulation motrice proposée par Jeannerod (2001). En effet, de tels déficits sont similaires à ceux observés chez ces populations lors de l'exécution réelle (notamment une diminution de la dextérité manuelle chez les personnes âgées et des troubles d'activation motrice chez les personnes atteintes de la MP) et appuient donc l'hypothèse selon laquelle il existerait une équivalence au niveau neural entre les états associés à la production d'actions motrices, que celles-ci soient exécutées réellement, simplement observées ou simulées mentalement.
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5

Hoang, Trong bien. « Switched observers and input-delay compensation for anti-lock brake systems ». Phd thesis, Université Paris Sud - Paris XI, 2014. http://tel.archives-ouvertes.fr/tel-00994114.

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Many control algorithms for ABS systems have been proposed in the literature since the introduction of this equipment by Bosch in 1978. In general, one can divide these control algorithms into two different types: those based on a regulation logic with wheel acceleration thresholds that are used by most commercial ABS systems; and those based on wheel slip control that are preferred in the large majority of academic algorithms. Each approach has its pros and cons [Shida 2010]. Oversimplifying, one can say that the strength of the first ones is their robustness; while that of the latter ones their short braking distances (on dry grounds) and their absence of limit cycles. At the midpoint of this industry/academy dichotomy, based on the concept of extended braking stiffness (XBS), a quite different class of ABS control strategies has been proposed by several researchers (see, e.g., [Sugai 1999] and [Ono 2003]). This concept combines the advantages from both the industrial and academic approaches. Nevertheless, since the slope of the tyre characteristic is not directly measurable, it introduces the question of real-time XBS estimation. The first part of this thesis is devoted to the study of this estimation problem and to a generalization of the proposed technique to a larger class of systems. From the technological point of view, the design of ABS control systems is highly dependent on the ABS system characteristics and actuator performance. Current ABS control algorithms on passenger cars, for instance the Bosch ABS algorithm, are based on heuristics that are deeply associated to the hydraulic nature of the actuator. An interesting observation is that they seem to work properly only in the presence of a specific delay coming from the hydraulic actuation [Gerard 2012]. For brake systems that have different delays compared to those of hydraulic actuators, like electric in-wheel motors (with a smaller delay) or pneumatic trailer brakes (with a bigger delay), they might be no longer suitable [Miller 2013]. Therefore, adapting standard ABS algorithms to other advanced actuators becomes an imperative goal in the automobile industry. This goal can be reached by the compensation of the delays induced by actuators. The second part of this thesis is focused on this issue, and to the generalization of the proposed technique to a particular class of nonlinear systems. Throughout this thesis, we employ two different linearization techniques: the linearization of the error dynamics in the construction of model-based observers [Krener 1983] and the linearization based on restricted state feedback [Brockett 1979]. The former is one of the simplest ways to build an observer for dynamical systems with output and to analyze its convergence. The main idea is to transform the original nonlinear system via a coordinate change to a special form that admits an observer with a linear error dynamics and thus the observer gains can be easily computed to ensure the observer convergence. The latter is a classical method to control nonlinear systems by converting them into a controllable linear state equation via the cancellation of their nonlinearities. It is worth mentioning that existing results for observer design by error linearization in the literature are only applied to the case of regular time scalings ([Guay 2002] and [Respondek 2004]). The thesis shows how to extend them to the case of singular time scalings. Besides, the thesis combines the classical state feedback linearization with a new method for the input delay compensation to resolve the output tracking problem for restricted feedback linearizable systems with input delays.
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Dziengel, Norman [Verfasser]. « Distributively Observed Events in Wireless Sensor Networks / Norman Dziengel ». Berlin : Freie Universität Berlin, 2016. http://d-nb.info/1095540157/34.

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Tami, Ramdane. « Formes normales d'observabilité : étendue, partielle et réduite ». Thesis, Orléans, 2014. http://www.theses.fr/2014ORLE2039.

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L'observateur est un outil essentiel pour accéder à l'information, non mesurable directement, d'un système dynamique. Dans le cas des systèmes non linéaires, il y a une grande carence concernant la synthèse d'observateur. Motivée par l'absence d'une solution générique, cette thèse élargit la classe des systèmes non linéaires pour lesquels on peut appliquer les observateurs connus. Dans l'approche adoptée, le système non linéaire est transformé à travers un changement de coordonnées sous forme normale d'observabilité qui a une structure adéquate à la synthèse d'observateurs. Les difficultés liées aux conditions d'existence d'un changement de coordonnées sont mises en évidence et des solutions sont proposées. Par conséquent, la classe des systèmes non linéaires qui peuvent se mettre sous une forme normale d'observabilité est élargie. Dans un premier temps, nous avons proposé une forme normale d'observabilité étendue dépendante de la sortie en augmentant l'espace d'état par des variables auxiliaires. Ainsi, nous avons établi les conditions nécessaires et suffisantes à l'existence d’un changement de coordonnées permettant d’obtenir une telle forme. En outre, nous avons proposé, pour certains modèles, des procédures heuristiques pour la mise sous forme normale d'observabilité étendue dépendante de la sortie. Dans un deuxième temps, nous avons traité la mise sous forme normale d'observabilité d'un système non linéaire partiellement observable. Enfin, nous avons abordé la transformation d'une classe spéciale de systèmes non linéaires sous la forme normale d'observabilité réduite. L'efficacité et l'intérêt des méthodes développées sont établis au travers de plusieurs applications
Observer is an essential means to access to no-measurable information of a dynamical system. In the case of nonlinear systems, there is a great deficiency concerning the observer design theory. Motivated by the lack of a generic solution to observer design, this thesis enlarges the class of nonlinear systems which admit a standard observer. Using a geometrical approach, the considered nonlinear systems are transformed through a change of coordinates into observer form, which has an adequate structure to the observer design. The difficulties related to the conditions on the existence of such a change of coordinates are highlighted and solutions are proposed. Therefore, the class of nonlinear systems which can be transformed under an observer form is expanded. Firstly, we proposed an extended output depending observer form which does not preserve the size of the original state space and we established the sufficient conditions for the existence of a change of coordinates enabling to construct the proposed form. Moreover, we proposed a heuristic procedure to construct the extended output depending observer form of some models. Secondly, we dealt with the observer form for some partially observable nonlinear systems. Finally, we discussed the transformation into the reduced observer form for a class of nonlinear systems. The efficiency and interest of the developed methods is established through several applications
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Pescim, Rodrigo Rossetto. « The new class of Kummer beta generalized distributions : theory and applications ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11134/tde-30012014-112231/.

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In this study, a new class of generalized distributions was developed, based on the Kummer beta distribution (NG; KOTZ, 1995), which contains as particular cases the exponentiated and beta generators of distributions. The main feature of the new family of distributions is to provide greater flexibility to the extremes of the density function and therefore, it becomes suitable for analyzing data sets with high degree of asymmetry and kurtosis. Also, two new distributions belonging to the new class of distributions, based on the Birnbaum-Saunders and generalized gamma distributions, that has as main characteristic the hazard function which assumes different forms (unimodal, bathtub shape, increase, decrease) were studied. In all studies, general mathematical properties such as ordinary and incomplete moments, generating function, mean deviations, reliability, entropies, order statistics and their moments were discussed. The estimation of parameters is approached by the method of maximum likelihood and Bayesian analysis and the observed information matrix is derived. It is also considered the likelihood ratio statistics and formal goodness-of-fit tests to compare all the proposed distributions with some of its sub-models and non-nested models. The developed results for all studies were applied to six real data sets.
Neste trabalho, foi proposta uma nova classe de distribuições generalizadas, baseada na distribuição Kummer beta (NG; KOTZ, 1995), que contém como casos particulares os geradores exponencializado e beta de distribuições. A principal característica da nova família de distribuições é fornecer grande flexibilidade para as extremidades da função densidade e portanto, ela torna-se adequada para a análise de conjuntos de dados com alto grau de assimetria e curtose. Também foram estudadas duas novas distribuições que pertencem à nova família de distribuições, baseadas nas distribuições Birnbaum-Saunders e gama generalizada, que possuem função de taxas de falhas que assumem diferentes formas (unimodal, forma de banheira, crescente e decrescente). Em todas as pesquisas, propriedades matemáticas gerais como momentos ordinários e incompletos, função geradora, desvios médio, confiabilidade, entropias, estatísticas de ordem e seus momentos foram discutidas. A estimação dos parâmetros é abordada pelo método da máxima verossimilhança e pela análise bayesiana e a matriz de informação observada foi derivada. Considerou-se, também, a estatística de razão de verossimilhanças e testes formais de qualidade de ajuste para comparar todas as distribuições propostas com alguns de seus submodelos e modelos não encaixados. Os resultados desenvolvidos foram aplicados a seis conjuntos de dados.
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Buchs, Arnaud. « Observer, caractériser et comprendre la pénurie en eau : une approche institutionnaliste de l'évolution du mode d'usage de l'eau en Espagne et au Maroc ». Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00703273.

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Ce mémoire de thèse a pour objet la pénurie en eau. Face aux analyses techniques a-historiques centrées sur la rareté physique de l'eau, nous développons une problématique sociale-contingente pour laquelle les usages de l'eau sont au cœur de l'explication. La première partie correspond à l'étape d'observation. Elle a pour objectif de retracer l'évolution du mode d'usage de l'eau à Almeria (Andalousie) et à Marrakech et Agadir (Maroc) entre la fin du XIXe siècle et aujourd'hui. Considéré comme domaine d'observation, le mode d'usage de l'eau (Arrus) qualifie l'articulation d'un volet " économique ", relatif à l'ajustement réciproque de l'offre et des usages finals de l'eau produite (formalisé par des normes-procédures) et d'un volet " institutionnel ", relatif aux normes sociales (qualifiées de normes-règles) présidant à la définition des droits de disposition sur les ressources en eau. Pour chacun des trois terrains, cette étape comprend une étude de terrain qualitative combinée à une analyse historiographique et à une analyse textuelle de documents de planification selon la méthode Alceste. Cette étape débouche sur la formulation de quatre faits stylisés chronologiques traduisant la succession de quatre phases constitutives du cycle de vie d'un mode d'usage de l'eau particulier. La deuxième partie est d'ordre théorique. Elle correspond aux étapes de caractérisation et de compréhension. Ces deux étapes reposent sur la mobilisation d'une grille théorique nouvelle élaborée par Billaudot sur la base d'une mise en rapport de l'institutionnalisme de Commons et de l'institutionnalisme sociologique de l'approche interprétative de l'économie des conventions (Boltanski et Thévenot). Qualifiée d'institutionnalisme historique et pragmatique, cette approche se présente comme une perspective d'approfondissement de l'institutionnalisme historique de la théorie de la régulation. Elle a pour objectif d'articuler genèse et fonction des institutions et conduit notamment à associer à chacune des modalités de règlement des transactions de Commons une valeur de référence et un bien supérieur. Ainsi, le mode d'usage de l'eau particulier ayant connu une phase de régime en Espagne et au Maroc au cours de la seconde moitié du XXe siècle est qualifié d'" hydrauliciste ". Il se caractérise par une représentation de l'eau essentiellement comme ressource d'allocation, dont l'abondance obtenue par des infrastructures à haute intensité de génie civil constitue une des prérogatives de l'État " moderne " qui, en aval, régit également son usage. L'identification des principales caractéristiques du mode d'usage " hydrauliciste " permet d'aboutir à la troisième étape, à savoir la compréhension des déterminants de son entrée en crise à partir des années 1980. D'une part, cette crise porte sur l'arrivée à terme des régularités antérieures quant à l'ajustement réciproque de l'offre et des usages finals de l'eau produite : on constate une raréfaction des ressources primaires (on qualifie cet aspect de " crise de la régulation "). D'autre part, elle correspond à la remise en question du cadre institutionnel qui soutient le volet économique (on constate une " crise du fondement du régime "). Ainsi, les normes sont partiellement disqualifiées par un double processus de délocalisation en faveur d'une décentralisation de la gestion de l'eau. De plus, le caractère non soutenable du mode d'usage antérieur conduit à l'émergence d'aspirations écologistes concrétisées par la proposition de nouvelles normes d'usage. Le registre de socialisation écologique pour lequel l'eau est comprise comme un milieu de vie se renforce. Au final, nous aboutissons à l'identification d'un nouveau mode d'usage actuellement en vigueur. Nous montrons qu'il ne procède pas d'une rupture paradigmatique mais correspond à un " régime de crise ".
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Filali, Rania Linda. « Sur la synchronisation et le cryptage de systèmes chaotiques à temps discret utilisant les techniques d'agrégation et la représentation en flèche des matrices ». Phd thesis, Ecole Centrale de Lille, 2013. http://tel.archives-ouvertes.fr/tel-00858272.

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L'objectif de cette thèse était de développer une méthode de synthèse de commande par retour d'état puis par observateurs offrant des conditions de synthèse non contraignantes dans le cas de systèmes non linéaires à temps discret. Dans cette méthode, est mise en exergue l'importance du choix de la description des systèmes sur l'étendue des résultats pouvant être obtenus lorsque la méthode d'étude de la stabilité est fixée. Ainsi l'utilisation des normes vectorielles comme fonction d'agrégation et du critère pratique de Borne et Gentina pour l'étude de la stabilité, associée à la description des systèmes par des matrices caractéristiques de forme en flèche de Benrejeb, a conduit à l'élaboration de nouvelles conditions suffisantes de stabilisation de systèmes dynamiques discrets non linéaires, formulées en théorèmes et corollaires. Ces résultats obtenus, sont ensuite exploités, avec succès, pour la formulation de nouvelles conditions suffisantes de vérification des propriétés de synchronisation pour les systèmes hyperchaotiques à temps discrets. Ensuite, le cas de synthèse d'observateur est validé dans deux types de transmission chaotique
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COLAVITO, Valeria. « The deployment of visual attention in time : evidence from normal observers and brain-damaged patients ». Doctoral thesis, 2007. http://hdl.handle.net/11562/337994.

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The study of the Attentional blink phenomenon has revealed to be one of the most useful tool to get insights abount the temporal constraints that limit rapid shifts in attentional redeployment. We report the interesting finding that, both in normal observers and, to some extent, also in brain-damaged patients, the magnitude of the interference effect described in the Attentional Blink can be reduced by the concomitant presentation of a task-irrelevant auditory stimulation which is able to induce a better temporal segmentation of the visual sequence. this argues against the unavoidable nature of the Attentional Blink effect, suggesting that rather than a fundamental limitation of attentional selection in time, it could be considered as a failure in optimally organize a flux of rapid and brief events.
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JIAN, JIA-WUN, et 簡嘉文. « Memory Colors in Deutan and Normal Observers ». Thesis, 2016. http://ndltd.ncl.edu.tw/handle/vfd3a2.

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碩士
國立臺灣科技大學
色彩與照明科技研究所
104
The aim of this study is to investigate memory colors of the familiar objects for deutan color vision, and compare the memory color differences between the normal and deutan observers. The rating score data obtained from visual assessment experiment is analyzed by a bivariate Gaussian function. Then memory-color rating ellipses of deutan color vison and normal color vision for the 12 familiar images (1 scene and 11 objects) are established in CIE u’v’ chromaticity diagram. For most of the familiar images, the deutan color vision get larger sizes of the rating ellipses normal color vision. The main differences between them are the length of major axis of memory-color rating ellipses, and the major axis of deutan’s rating ellipses are parallel to the red-green direction. It’s possible to distinguish deutan color vision from normal color vision according to the memory-color rating ellipses.
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CHEN, MING-XIAN, et 陳明顯. « The psychophysical test in dark adaptation on glaucomatous patient and normal observers ». Thesis, 1990. http://ndltd.ncl.edu.tw/handle/34931233165148636567.

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LAI, ZHI-HUAN, et 賴志桓. « The cut-off freq. on simple glaucomatous patient and normal observers in sinusoidal filcker stimulation ». Thesis, 1990. http://ndltd.ncl.edu.tw/handle/88709635560452951484.

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Monchusi, Bernice Andrieca. « The molecular basis of the phenotype observed when normal cells recover from camptothecin and methyl pyruvate ». Thesis, 2018. https://hdl.handle.net/10539/25620.

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A thesis submitted to the Faculty of Science under the School of Molecular and Cell Biology, University of the Witwatersrand, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, 2017.
Cancer has become a major cause of death in modern society. New cancer cases are estimated to increase to 22.2 million by 2030. Many chemotherapeutic drugs, such as irinotecan, target the p53 pathway in rapidly dividing cells. However, chemotherapeutic drugs possess little discrimination between normal and cancer cells since they target DNA replication, a normal physiological process. Many studies indicate that cancer and normal cells prefer different glucose metabolic pathways. Cancer cells rely mainly on glycolysis while normal cells prefer the oxidative phosphorylation (OXPHOS). We hypothesise that manipulating the known metabolic programme of cancer cells to follow the OXPHOS pathway experienced by normal cells may alleviate side effects experienced by normal cells and accelerate cancer cell death. In order to enhance OXPHOS optimal pyruvate levels were used. To investigate the effect of this on normal and cancer cell division, cell viability and cytotoxicity was measured in real-time using xCELLigence technology. Flow cytometry was then used to determine the mode of cell death and cell cycle changes induced by the various treatments. In order to characterise the molecular bases of this, differential gene expression upon treatment with the various drugs was measured by RT-PCR and Western blot analysis. Furthermore, we conducted microarray analyses using the Human Cancer PathwayFinder array to determine pathways affected by the drug combination in A549 lung fibroblast cancer and a normal lung fibroblast (MRC-5). Differentially expressed genes with a fold change ≥ 2 were analysed by PANTHER, GeneMania and Reactome. Overall, this study shows that the reversal of the metabolic program in A549 and MDA-MB 231 cancer cells with chemotherapeutic agents accelerates the death of cancer cells while promoting the survival of normal MRC-5 cells. However, in the breast cancer cell line, MDA-MB 231 with mutant p53, it is observed that inhibition of proliferation is by another cell death mechanism. RT-PCR and western blot analyses indicate that introduction of exogenous methyl pyruvate enhanced the p53/p21 axis of the apoptotic pathway resulting in cancer cell death. While promoting survival in MRC-5 normal lung fibroblast cells by turning off the p53/p21 axis of the apoptotic pathway. Furthermore, the introduction of exogenous methyl pyruvate promotes MRC-5 cell proliferation by modulating the expression of RBBP6 isoform 1 and isoform 3. Microarray analysis indicates alterations in specific genes promote the survival and growth of MRC-5 normal cells and death of A549 lung cancer cells. This knowledge may provide an opportunity to protect patients who undergo chemotherapy from the harsh side-effects and increase the success rate of chemotherapeutic drugs.
LG2018
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Valdez, Susana Santos Ângelo Salgado. « Perceived and observed translational norms in biomedical translation in the contemporary Portuguese translation market : a quantitative and qualitative product- and process-oriented study ». Doctoral thesis, 2018. http://hdl.handle.net/10451/38410.

Texte intégral
Résumé :
At the intersection of Descriptive Translation Studies and Social Sciences, this interdisciplinary, empirical, experimental and descriptive study addresses the question of ascertaining whether and to what extent translators’ decision-making processes are influenced by what translators believe to be the expectations of other agents, namely revisers and readers. Whereas preferences by translators have previously been described and explained in the literature, it is still unclear what revisers’ and readers’ translational preferences are and what expectations they have about translators and the translated text. In addition, there is still a lack of understanding about how translators translate, how translators think they should translate, and what translators believe to be the expectations of other translators, revisers, and readers. In order to address these issues, this study focuses on the distinction between observed and perceived norms in the translation of biomedical texts from English to European Portuguese in contemporary Portugal. It zooms in on preferences regarding source and target orientation in translation, comparing both the practice and beliefs of sixty agents with different roles and levels of experience: novice translators, experienced translators, revisers, and health professionals (representing the intended audience of the target text). In particular, the specific question which drives this research is: considering English to European Portuguese biomedical translation in the contemporary Portuguese market, are the observed translational norms and perceived translational norms of translators, revisers and readers similar or different regarding source and target orientation? Mainly informed by the metatheoretical, theoretical, and methodological discussions of Toury (1995, 2012), Hermans (1991; 1996; 1999a; 1999b; 2000), Bicchieri (2006, 2017a, and 2017b), and Rosa (2016c), norms and expectations emerge as a powerful descriptive tool in studying norm-governed behavior and specifically to capture and further understand the complexities of decision-making processes in translation. Based on an exploratory and preliminary case study, this dissertation first sets out to explore the practice of biomedical translation in Portugal to understand who the agents involved in biomedical translation are, what they do, what for, in what types of texts, with what function and for whom. To this end, a mixed corpus of 700,000 words of different text-types of medical and biomedical content translated from English to European Portuguese was analyzed, including e-mail exchanges between translators and project managers. This analysis shows that biomedical translation involves a complex structure of translation agents performing different translation tasks, among which revisers play a pivotal role. The most common text-type identified is instructional texts about medical devices aimed at health professionals. Following this preliminary assessment, for the main study, a mixed methodology based on quantitative and qualitative product- and process-oriented approaches was employed to study (i) thirty translations of an instructional text about a medical device intended for health professionals, (ii) the translational preferences of fifteen revisers and fifteen health professionals regarding the same instructional text, and (iii) the expectations of these translators, revisers, and health professionals about biomedical translation. The experiment involved eliciting data from fifteen novice translators and fifteen experienced translators asked to translate an instructional text. The data included keylogging and screen recording data, interim versions and target texts, and it was triangulated to produce an empirical description of translation phenomena of biomedical content. The data was analyzed in terms of (i) the translators’ translation problems, (ii) the corresponding observed translation solutions, and (iii) the source and target orientation of the solution types. In addition, the thirty translators, together with fifteen specialized revisers and fifteen health professionals, were asked to answer a questionnaire aimed at eliciting different types of beliefs and expectations to (i) analyze the translators’ expectations and perceptions about how they should translate and how other translators, revisers, and readers believe translators should translate, (ii) identify the revisers’ and health professionals’ translational preferences, and (iii) describe an elaborate network of beliefs and expectations affecting the translators’ decision-making processes that result from the interaction of several agents with different roles and levels of normative control, and (iv) to propose explanatory hypotheses for the identified translation phenomena. From the product analysis, the study found that (i) the novice and experienced translators opted for both source- and target-oriented translation solutions, while (ii) the revisers and health professionals opted for the most target-oriented translations. The most common target-oriented translation solutions (i.e., explicitation, implicitation, hyponymy/hypernymy, omission, addition, and other information changes) were also analyzed in terms of their textual function and potential motivations to propose explanatory hypotheses. From the process analysis, the comparison of the translators’ interim versions and final versions indicated that while (i) the novice translators proceeded from less source-oriented versions to more source-oriented ones, (ii) the experienced translators proceeded from more source-oriented versions to less source-oriented ones. From the analysis of the beliefs and expectations, the study found that (i) while the novice and experienced translators described the appropriateness of a translation using both source- and target-oriented criteria, (ii) the revisers and health professionals reported target-oriented criteria as the most important to describe the appropriateness of a translation. Overall, the novice and experienced translators’ behavior and expectations suggested initial norms of source and target orientation, revealing that aspects of both the source and target cultures and languages are valued. The analysis of the processes of the novice and experienced translators also suggested that there are other possible motivations for source and target orientation connected with (i) the number of translation problems and (ii) the time taken to translate the source text. Revisers’ and health professionals’ behavior and expectations suggested an initial norm of target orientation, revealing a higher valuation of the target culture, language, and prospective reader. The study also found that even though accuracy (a source-oriented criterion) is a common expectation among all agents, expectations regarding literal translation (source-oriented), transparency, and invisibility (target-oriented) are not shared by translators, revisers, and health professionals. By showing how perceptions and expectations about source and target orientation may influence translators’ textual regularities, the findings of this descriptive, target-oriented study add to our understanding of translational norms in general and in biomedical translation in particular. The main implications of this study are of four different types: theoretical, methodological, practical and didactic. This study raises theoretical implications that have a bearing on translational norms. In particular, it proposes a definition of translational norms that (i) allows for a distinction between object- and meta-level discourses (building on Rosa 2016c), (ii) explicitly includes the role of agents’ expectations as a driver of behavior, connoting what is considered appropriate and inappropriate (adapted from Bicchieri 2017a), and (iii) stresses the need to address different and sometimes conflicting perceptions of what is considered appropriate and inappropriate in a particular community. In addition, the study also offers methodological tools to address norms by proposing that translational norms can be further studied through the comparative analysis of a detailed taxonomy of beliefs, attitudes, and expectations elicited from different agents with various roles (adapted from Bicchieri 2017a). It also describes how translation problems can be identified based on keylogging and screen recording data through a fine-grained classification of translation units based on primary and secondary indicators of translation problems (building on Krings 1986; and Göpferich 2010b) in order to reconstruct the decision-making processes of the translator and, in particular, the methodological distinction between an interim solution and a consciously postponed decision. The described regularities and expectations expressed by the data also have implications for translation practice and translator training. The findings can be used to develop concrete solutions to address translation competence and best practices for the language industry. It is recommended that students should be specifically trained to raise self-awareness to monitor and assess, in their translation and revision decision-making processes, how their expectations about translation and their perceived expectations about revisers and readers can be related to their translation solutions. Given that communication between professional translators and revisers can be a factor for the distinct perceptions identified regarding expectations, best practices for peer feedback are also proposed. In addition, universities are called to action to promote communication among professional translators, revisers and readers in specialized domains, addressing at the same time the gap between academic work and the language industry.
Posicionando-se na intersecção dos Estudos Descritivos de Tradução e das Ciências Sociais, o presente estudo interdisciplinar empírico-experimental aborda a questão da influência dos processos de tomada de decisão dos tradutores pelo que os tradutores acreditam ser as expectativas de outros agentes, nomeadamente se os processos dos tradutores são influenciados pelas expectativas das expectativas de outros tradutores, revisores e leitores e em que medida. Embora as preferências dos tradutores já tenham sido descritas e explicadas na literatura, as preferências tradutórias de revisores e leitores, assim como as suas expectativas referentes aos tradutores e ao texto traduzido, foram ainda pouco abordadas. Uma outra lacuna na literatura diz respeito a como os tradutores traduzem, como os tradutores pensam que deviam traduzir e o que os tradutores acreditam ser as expectativas de outros tradutores, revisores e leitores. Para abordar estas questões, o presente estudo centra-se na distinção entre as actuais normas observadas e as normas presumidas na tradução biomédica no par de línguas inglês-português europeu em Portugal. O foco recai sobre as preferências referentes às culturas e línguas de partida e chegada na tradução, comparando práticas e convicções de sessenta agentes com diferentes cargos e níveis de experiência: tradutores júnior, tradutores experientes, revisores e profissionais de saúde (em representação do público-alvo do texto de chegada). Assim, a questão que norteia esta investigação é: no contexto da tradução biomédica contemporânea no par de línguas inglêsportuguês europeu, serão as normas tradutórias observadas e presumidas de tradutores juniores e experientes, de revisores e de leitores relativamente às culturas e línguas de partida e chegada semelhantes ou diferentes? As normas e as expectativas, fundamentadas pelos debates metateóricos, teóricos e metodológicos principalmente de Toury (1995, 2012), Hermans (1991; 1996; 1999a; 1999b; 2000), Bicchieri (2006, 2017a, and 2017b) e Rosa (2016c), apresentam-se como uma ferramenta descritiva robusta para o estudo do comportamento regido por normas e, em particular, para descrever e aprofundar o conhecimento em relação às complexidades dos processos de tomada de decisão em tradução. Com base num estudo de caso exploratório e preliminar, a presente dissertação estabelece como primeiro objetivo explorar a prática de tradução biomédica em Portugal, de forma a compreender quem são os agentes envolvidos na tradução biomédica, o que fazem, com que objetivos, em textos de que tipo, qual a função dos mesmos e para quem. Neste sentido, foi analisado um corpus de 700 mil palavras de diferentes tipos de texto de conteúdos médicos e biomédicos traduzidos de inglês para português europeu, incluindo mensagens de correio eletrónico trocadas entre tradutores e gestores de projeto. Esta análise demonstra que a tradução biomédica involve uma rede complexa de agentes de tradução que levam a cabo diferentes tarefas tradutórias, nas quais os revisores desempenham um papel fundamental. O tipo de texto mais comum identificado é o texto instrutivo de dispositivos médicos dirigidos a profissionais de saúde. No seguimento desta avaliação preliminar, para o estudo principal foi adoptada uma metodologia mista com base em abordagens quantitativas e qualitativas do produto e processo, de forma a estudar (i) trinta traduções de um texto instrutivo de um dispositivo médico dirigido a profissionais de saúde, (ii) as preferências tradutórias de quinze revisores e quinze profissionais de saúde relativamente ao mesmo texto instrutivo e (iii) as expectativas destes tradutores, revisores e profissionais de saúde sobre a tradução biomédica. A experiência envolveu a elicitação de dados de quinze tradutores júnior e quinze tradutores experientes, a quem foi pedido que traduzissem o texto instrutivo. Os dados incluíram registo de movimentos no teclado do computador e gravação do ecrã, versões preliminares e textos de chegada; os mesmos foram triangulados de modo a possibilitar uma descrição empírica do fenómeno tradutório de conteúdos biomédicos. Os dados foram analisados em termos (i) dos problemas tradutórios dos tradutores, (ii) das correspondentes soluções de tradução observadas e (iii) da orientação dos tipos de solução para as culturas e línguas de partida e chegada. Estes trinta tradutores, conjuntamente com os quinze revisores especializados e quinze profissionais de saúde, foram também convidados a responder a um questionário com o objetivo de elicitar os diferentes tipos de convicções e expectativas, de forma a (i) analisar as expectativas e perceções dos tradutores sobre a forma como estes traduzem e como outros tradutores, revisores e leitores acreditam que os tradutores deviam traduzir, (ii) identificar as preferências tradutórias dos revisores e dos profissionais de saúde e (iii) descrever uma rede complexa de convicções e expectativas que afetam os processos de tomada de decisão dos tradutores e que resulta da interação entre vários agentes com diferentes cargos e níveis de controlo normativo (iv) para propor hipóteses explicativas referentes ao fenómeno de tradução identificado. Com base na análise do produto, o estudo concluiu que (i) os tradutores juniores e experientes optaram por soluções de tradução regidas pelas culturas e línguas de partida e chegada e (ii) os revisores e os profissionais de saúde optaram pelas traduções maioritariamente regidas pela língua e cultura de chegada. As soluções de tradução regidas pela cultura e língua de chegada (i.e., explicitação, implicitação, hiperonímia/hiponímia, omissão, adição e outras alterações de conteúdo) também foram analisadas quanto à sua função textual e potenciais motivações para propor hipóteses explicativas. Com base na análise do processo, a comparação entre as versões preliminares e os textos de chegada indicou que, embora (i) os tradutores juniores progredissem de versões menos orientadas para a partida para mais orientadas para a partida, (ii) os tradutores experientes progrediram de versões mais orientadas para a partida para menos orientadas para a partida. Com base na análise das convicções e das expectativas, o estudo concluiu que (i) enquanto os tradutores juniores e experientes recorreram a critérios regidos pelas culturas e línguas de partida e chegada para descrever a “correção” de uma tradução, (ii) os revisores e os profissionais de saúde indicaram critérios regidos pelas culturas e línguas de chegada como sendo os mais importantes para descrever a “correção” de uma tradução. Em suma, o comportamento e as expectativas dos tradutores juniores e experientes apontam para as normas iniciais de orientação para a cultura e língua de partida e de orientação para a cultura e língua de chegada, revelando assim uma valorização de aspetos de ambas as culturas e línguas. Também se apontam outras possíveis motivações para as orientações para as culturas e línguas de partida e de chegada baseadas na análise dos processos de tradutores juniores e experientes referentes (i) ao número de problemas de tradução e (ii) ao tempo empreendido para traduzir o texto de partida. O comportamento e as expectativas dos revisores e profissionais de saúde apontam para uma norma inicial regida pela cultura e língua de chegada, revelando uma valorização superior das culturas e línguas de chegada e do leitor prospetivo. O estudo concluiu também que embora a exatidão (um critério regido pela cultura e língua de partida) seja uma expectativa transversal a todos os agentes, as expectativas referentes à tradução literal (regida pela cultura e língua de partida), transparência e invisibilidade (regida pela cultura e língua de chegada) não são partilhadas pelos tradutores, revisores e profissionais de saúde. Ao descrever como as perceções e as expectativas referentes à regência das culturas e línguas de partida e chegada podem influenciar as regularidades textuais dos tradutores, as conclusões do presente estudo descritivo constituem um contributo para o aprofundamento do conhecimento sobre as normas tradutórias, em geral, e da tradução biomédica, em particular. As principais implicações do presente estudo são de quatro tipos: teóricas, metodológicas, práticas e pedagógicas. Ao nível teórico, este estudo propõe uma definição de normas tradutórias que (i) considera a distinção entre discursos ao nível objeto e ao nível meta (baseando-se em Rosa 2016c), (ii) inclui explicitamente o papel das expectativas dos agentes enquanto força motriz de comportamento, conotando o que se considera “correto” e “incorreto” (adaptado de Bicchieri 2017a) e (iii) enfatiza a necessidade de abordar perceções diferentes e, por vezes, contrárias em relação ao que é considerado como “correto” e “incorreto” numa comunidade específica. Além disso, o estudo apresenta também ferramentas metodológicas, propondo que o estudo das normas tradutórias possa ser aprofundado através da análise comparativa de uma classificação pormenorizada de convicções, atitudes e expectativas elicitadas de diferentes agentes com cargos diversos (adaptado de Bicchieri 2017a). Também descreve como os problemas tradutórios podem ser identificados com base em dados dos registos de movimentos no teclado do computador e gravação de ecrã através uma classificação detalhada das unidades de tradução baseada em indicadores primários e secundários de problemas tradutórios (adaptado a partir de Krings 1986 e Göpferich 2010b) para reconstruir os processos de tomada de decisão do tradutor e, mais especificamente, a distinção metodológica entre uma solução preliminar e uma decisão conscientemente adiada. As regularidades descritas e as expectativas expressas também têm implicações para a prática de tradução e para a formação de tradutores. Os resultados podem ser integrados na prática tradutória e na formação de tradutores, de forma a desenvolver soluções concretas para abordar as competências tradutórias e boas práticas na indústria das línguas. Recomenda-se que os estudantes sejam formados especificamente no sentido de se promover a consciencialização de modo a monitorizarem e avaliarem, nos seus processos de tomada de decisão de tradução e revisão, de que forma as suas expectativas sobre a tradução e as suas expectativas presumidas sobre os revisores e leitores têm impacto nas suas soluções de tradução. Dado que a comunicação entre tradutores profissionais e revisores pode contribuir para as perceções distintas identificadas relativamente às expectativas, também são propostas boas práticas para o feedback entre pares. Além disso, as universidades são chamadas a atuarem para promoverem a comunicação entre tradutores profissionais, revisores e leitores nos domínios especializados, contribuindo simultaneamente para colmatar o fosso entre as comunidades profissional e académica.
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