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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.
361

Determinação de fatores de interferência de produtos de fissão do urânio na análise por ativação neutrônica / Determination of uranium fission products interference factors in neutron activation analysis

RIBEIRO JUNIOR, IBERE S. 10 November 2014 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2014-11-10T11:38:41Z No. of bitstreams: 0 / Made available in DSpace on 2014-11-10T11:38:41Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
362

A história no banco dos réus : leis de impunidade, memória da repressão política e as decisões da Suprema Corte na Argentina e no Brasil

Gallo, Carlos Artur January 2016 (has links)
No contexto da Guerra Fria, o Brasil e a Argentina tiveram suas estruturas de poder ocupadas por ditaduras civis-militares alinhadas aos preceitos da Doutrina de Segurança Nacional (DSN). Impactando na organização política, social, cultural e econômica dos países referidos, os militares no poder foram responsáveis por um incremento no uso da violência, de modo que, como saldo da repressão há um número significativo de pessoas que foram presas, torturadas, mortas e/ou desaparecidas por agentes da repressão. Em junho de 2005, na Argentina, e em abril de 2010, no Brasil, a Corte Suprema desses países levou a julgamento causas que tratavam da possibilidade de processar e punir os envolvidos nos crimes cometidos pelo aparato repressivo, sendo produzidas decisões bastante diferentes: na Corte Suprema de Justicia de la Nación (CSJN), a maioria dos Ministros declarou a nulidade das “leis de impunidade”, uma vez que mantê-las contrariaria a normativa internacional dos direitos humanos vigente; no Supremo Tribunal Federal (STF), também pela maioria dos votos, foi decidido que a interpretação de que a Lei da Anistia de 1979 havia anistiado aos repressores era correta e estava de acordo com a nova Constituição. Tendo esses elementos como ponto de partida, esta tese analisou o impacto que os processos de transição brasileiro e argentino tiveram no novo cenário político iniciado com o fim dessas ditaduras. Fazendo uso do método comparado de análise, a pesquisa parte do pressuposto de que o modo como se deu a transição (mais negociada ou mais abrupta) repercute na manutenção de legados autoritários na nova democracia, influenciando na forma como o Judiciário se manifesta sobre questões relacionadas à punição das violações aos direitos humanos praticadas pela ditadura. Em síntese, a comparação dos casos selecionados para este estudo permitiu observar que o tipo de transição ocorrido impactou, de fato, no modo como uma agenda política sobre o tema das violações foi elaborada nesses países. No contexto argentino, onde se deu uma transição abrupta, as elites civis e militares no poder tiveram sua capacidade de resguardar garantias políticas duradouras reduzida e foi fortalecida a causa dos direitos humanos. No caso brasileiro, onde ocorreu uma transição bastante negociada, os termos dos pactos que garantiram a saída das Forças Armadas do poder puderam ser mantidos em longo prazo, sendo reforçados por um conjunto de legados autoritários que garantem a impunidade dos envolvidos com a repressão. Ainda que mudanças conjunturais possam repercutir no estabelecimento de políticas de memória em cada contexto, tendo em vista que, mesmo na Argentina, a trajetória dessas políticas específicas foi marcada por avanços e recuos, é fato que, em contextos como o brasileiro, é mais difícil formular políticas sobre o tema, uma vez que não se realize uma ruptura com resquícios da ditadura que se mantêm convivendo com a democracia. / In the context of the Cold War, Brazil and Argentina had their power structures occupied by civilians and military dictatorships aligned with the requirements of National Security Doctrine (NSD). Impacting the political, social, cultural and economic organization of these countries, the military in power were responsible for more use of violence, so that, as the balance of the repression there is a significant number of people who were arrested, tortured, killed and/or disappeared by agents of repression. In June 2005, in Argentina, and in April 2010, in Brazil, the Supreme Court of these countries put on trial cases that addressed the possibility of prosecuting and punishing those involved in the crimes committed by the repressive apparatus, several decisions being produced: in the Supreme Court de Justicia de la Nación (SCJN), most Ministers declared the nullity of "impunity laws", since keeping them contrary to international rules of the current human rights; the Federal Supreme Court (FSC), also by majority vote, it was decided that the interpretation of the Amnesty Law of 1979 had pardoned the repressors was correct and was in accordance with the new Constitution. Taking these elements as a starting point, this thesis analyzed the impact that the Brazilian transition and Argentina had the new political scene started with the end of these dictatorships. Making use of the comparative method of analysis, the research assumes how the transition was (most traded or most abrupt) affects the maintenance of authoritarian legacy in the new democracy, influencing the way the judiciary manifests about issues related to the punishment of human rights violations committed by the dictatorship. In summary, comparison of the cases selected for this study allowed us to observe that the type of transition occurred impacted, in fact, the way a political agenda about the subject of violations was developed in these countries. In the Argentine context, where there was an abrupt transition, civilian and military elites in power had their capacity reduced to safeguard permanent political guarantees and it was strengthened the cause of human rights. In Brazil, where there was a transition fairly negotiated, the terms of the agreement that ensured the output of the Armed Forces from the power could be maintained in the long run, they were reinforced by a set of authoritarian legacies that guarantee the impunity of those involved in the repression. Although changes may reflect the establishment of memory policies in each context, given that even in Argentina, the trajectory of these specific policies was marked by advances and retreats, the fact is that, in contexts such as Brazil, it is more difficult to formulate policies about the topic, since it is not carried out a break with remnants of the dictatorship remain living with democracy. / Durante la Guerra Fría, Brasil y Argentina tuvieron sus estructuras de poder ocupadas por dictaduras cívico-militares vinculadas a la Doctrina de Seguridad Nacional (DSN). Teniendo impacto en la organización política, social, cultural y económica de los dos países mencionados, los militares en el poder fueron responsables por incrementar la aplicación de la violencia, de manera que, como saldo de la represión, hay un número significativo de personas que fueron detenidas, torturadas, muertas y/o desaparecidas por los agentes de la represión. En junio de 2005, en Argentina, y en abril de 2010, en Brasil, la Corte Suprema de estos países ha llevado a juicio casos sobre las posibilidades de procesar y punir a los involucrados en los crímenes del aparato represivo, siendo producidas decisiones muy diferentes: la Corte Suprema de Justicia de la Nación (CSJN) ha declarado, por la mayoría de los votos de sus Ministros, la nulidad de las “leyes de impunidad”, una vez que mantenerlas era algo contrario a la normativa internacional de derechos humanos vigente; el Supremo Tribunal Federal (STF), al contrario, ha declarado, también por la mayoría de los votos, que la interpretación de que la Ley de Amnistía de 1979 había amnistiado a los represores era correcta y estaba de acuerdo con la nueva Constitución. Impartiéndose de esos elementos, esta tesis hace un análisis del impacto de los procesos de transición a la democracia en el nuevo escenario político empezado con el final de las dictaduras. Aplicando el método comparado, la investigación plantea que la manera como se ha desarrollado la transición (más negociada o más abrupta) repercute en la manutención de legados autoritarios en la nueva democracia, reflejando en el modo como el Poder Judicial va a manifestarse sobre la punición de las violaciones a los derechos humanos llevadas a cabo por la dictadura. En síntesis, la comparación de los juicios ha permitido observar que el modelo de transición ha impactado, de hecho, en la manera como fue elaborada una agenda política sobre las violaciones en estos países. En Argentina, donde ocurrió una transición abrupta, las élites civiles y militares en el poder tuvieron minimizada su capacidad de resguardar garantías políticas duraderas, haciéndose fuerte en este contexto la causa de los derechos humanos. En Brasil, la transición ha sido muy negociada, de manera que los términos de los pactos que han garantizado que las Fuerzas Armadas dejarían al poder pudieron mantenerse en el nuevo régimen, siendo fortalecidos por un conjunto de legados autoritarios que sostienen la impunidad de los involucrados con la represión. Aunque cambios de contexto puedan generar impacto en el establecimiento de políticas de memoria en cada país, como se puede verificar en el caso argentino, donde la trayectoria de esas políticas está marcada por avances y retrocesos, queda evidente que, en países como Brasil, es más complicado formular políticas sobre la temática en cuanto no se realice una ruptura con fragmentos de la dictadura que se mantienen en la democracia.
363

Determinação de fatores de interferência de produtos de fissão do urânio na análise por ativação neutrônica / Determination of uranium fission products interference factors in neutron activation analysis

RIBEIRO JUNIOR, IBERE S. 10 November 2014 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2014-11-10T11:38:41Z No. of bitstreams: 0 / Made available in DSpace on 2014-11-10T11:38:41Z (GMT). No. of bitstreams: 0 / A análise por ativação com nêutrons é um método utilizado na determinação de diversos elementos em diferentes tipos de matrizes. Entretanto, quando a amostra contém altos teores de U ocorre o problema de interferência devido aos produtos de fissão do isótopo 235U. Um dos métodos de tratar este problema é fazer a correção usando fatores de interferência devido à fissão do U para os radionuclídeos utilizados nas análises dos elementos. No presente estudo foram determinados os valores dos fatores de interferência devido à fissão do U para os radioisótopos 141Ce, 143Ce,140La, 99Mo, 147Nd, 153Sm e 95Zr no reator nuclear de pesquisas IEA-R1 do IPEN-CNEN/SP. Esses fatores de interferência foram determinados experimentalmente, por meio da irradiação dos padrões sintéticos em uma determinada posição do reator, e teoricamente, determinando a razão dos fluxos de nêutrons epitérmicos e térmicos na mesma posição onde os padrões sintéticos foram irradiados e utilizando parâmetros nucleares da literatura. Os fatores de interferência obtidos foram comparados com os valores reportados em outros estudos. Para avaliar esses fatores de interferência, eles foram aplicados em análises dos elementos alvo deste estudo, nos materiais de referência certificados NIST 8704 Buffalo River Sediment, IRMM BCR-667 Estuarine Sediment e IAEA-SL-1 Lake Sediment. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
364

Estudo das impurezas radioativas gama emissoras presentes nos radiofármacos produzidos no IPEN-CNEN/SP / Study of the radioactive impurities gamma emitters present in the radiopharmaceutical solutions produced at IPEN-CNEN/SP

ALMEIDA, JAMILLE da S. 22 November 2017 (has links)
Submitted by Pedro Silva Filho (pfsilva@ipen.br) on 2017-11-22T17:07:51Z No. of bitstreams: 0 / Made available in DSpace on 2017-11-22T17:07:51Z (GMT). No. of bitstreams: 0 / Este trabalho tem como objetivo investigar a concentração de impurezas radioativas gama emissoras presentes nas soluções dos radiofármacos produzidos no Instituto de Pesquisas Energéticas e Nucleares - IPEN em São Paulo. Para que este radiofármaco possa ser utilizado adequadamente, sua qualidade deve ser avaliada de acordo com os procedimentos estabelecidos de acordo com os \"Requisitos Gerais para a Competência de Laboratórios de Teste e Calibração\", ISO / IEC 17025: 2005 e pelas \"Boas Práticas de Fabricação\" (BPF), controladas pela ANVISA (Agência Nacional de Vigilância Sanitária), no Brasil. Para determinar a atividade, dos radiofármacos das impurezas gama emissoras, foi utilizado um espectrômetro gama de alta resolução em duas distâncias fonte-detector; uma de 18 cm e outra de 1,7 cm. Para a distância de 18 cm, o espectrômetro HPGe foi calibrado com energias gama entre 81 kev e 1408 kev, medindo ampolas seladas de 60Co, 133Ba, 137Cs e 152Eu, padronizadas no Laboratório de Metrologia Nuclear (LMN) do IPEN. Para impurezas com baixas atividades, utilizou a distância fontedetector de 1,7 cm. A esta distância, o efeito soma em cascata é muito elevado, tornando difícil a medição das ampolas de calibração padrão, com isso, a curva de eficiência do espectrômetro foi obtida por um código de simulação de Monte Carlo, desenvolvido no IPEN. Neste código, todos os detalhes do sistema de detecção são modelados e as curvas de resposta para raios X e raios gama são calculadas pelo código de transporte de radiação MCNPX. Os espectros gama foram analisados pelo programa Alpino, que aplica o método de integração numérica da área sob os fotopicos de absorção total. Para as impurezas gama emissoras não detectadas visualmente, os limites de detecção foram calculados a partir da taxa de contagem de fundo, sob a área do pico de interesse. As soluções radioativas analisadas foram 67Ga,99Mo, 99mTc, 111In, 131I, 153Sm, 177Lu e 201Tl. Os resultados da relação entre a atividade do radionuclídeo em análise e as impurezas identificadas apresentaram acordo com os certificados de análise dos fabricantes, assim como, com as especificações da ANVISA. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
365

Étude du vieillissement normal des fonctions frontales : impact sur l’autonomie et la qualité de vie / Study of frontal lobe functions in normal aging : impact on autonomy and quality of life.

Calso, Cristina 17 November 2017 (has links)
En s’appuyant sur l’hypothèse frontale du vieillissement (West, 1996), ce travail vise à évaluer le vieillissement normal de capacités frontales (contrôle exécutif, prise de décision, énergisation, métacognition ; Stuss, 2008)et à analyser les liens éventuels entre ces habiletés,l’autonomie et la qualité de vie des aînés. Quarante personnes jeunes (26±5 ans), 40 âgées (68,7±3,7 ans)et 30 très âgées (83,4±3,5 ans) en bonne santé ont participé à notre étude. Les aînés ne montraient pas de traits dépressifs/anxieux, ni de déclin cognitif typiques d’un vieillissement pathologique. Ils présentaient une autonomie et une qualité de vie satisfaisantes.Certaines habiletés cognitives semblent se détériorer après 65 ans (flexibilité, énergisation, prise de décision sous risque explicite, théorie de l’esprit, détection de la coopération/tromperie), d’autres après 80 ans (fluence verbale, mémoire épisodique, dénomination, inhibition,prise de décision en situation ambiguë), d’autres encore seraient préservées (lecture, rappel immédiat,réalisation de tâches de flexibilité spontanée et de temps de réaction simple). La conscience que les sujets ont d’eux-mêmes dépendrait de leur âge. Trois profils distincts de fonctionnement frontal ont été décrits pour chaque groupe de participants, montrant une variabilité intra groupe importante. Le niveau d’autonomie des personnes âgées serait associé au contrôle exécutif,celui de qualité de vie à l’énergisation et à la métacognition. Ces résultats vérifient partiellement nos hypothèses et conduisent à envisager le développement de programmes d’entraînement cognitif multidimensionnels, susceptibles d’influencer la sphère personnelle des aînés. / Starting from the “frontal lobe hypothesis of cognitive aging” (West, 1996), the main objective of this work is to study frontal lobe functions (executive control, decision making,energization, metacognition; Stuss, 2008) and their possible associations with levels of autonomy and quality of life in normal aging. Forty young adults (26±5years), forty old adults (68,7±3,7 years) and thirty very old adults (83,4±3,5 years) participated to our study.These healthy subjects didn’t show any depressive/anxious symptoms and global cognitive decline, which are frequently observed in pathologic alaging. They have a good level of autonomy and general satisfaction of life. A number of frontal lobe abilities seem to decrease after 65 years old (flexibility,energization, explicit decision-making, theory of mind,detection of cooperative and deceptive situations).Other functions decline after 80 years old (verbalfluency, episodic memory, naming, inhibition, implicit decision-making). Reading, immediate recall, realization of spontaneous flexibility and simple reaction time tasks are preserved with aging. Self-consciousness seems to depend on individuals’ age. We have described three different clusters of the frontal functioning for each group of participants, showing the existence of animportant intragroup variability. Old adults’ level of autonomy seems to be associated with the executive control, old adults’ quality of life correlated with the energization and metacognitive functions. These resultsconfirm in part our hypothesis and support the development of multidimensional cognitive training programs, which could impact old adults’ personal sphere.
366

Eliminating propositional attitudes concepts / Pourquoi éliminer les concepts d'attitudes propositionnelles?

Bantegnie, Brice 03 September 2015 (has links)
Dans cette thèse je défends l'élimination des concepts d'attitudes propositionnelles. Dans le premier chapitre, je présente les thèses éliminativistes en philosophie de l'esprit et des sciences cognitives contemporaines. Il y a deux types d'éliminativisme: le matérialisme éliminatif et l'éliminativisme des concepts. Il est possible d'éliminer les concepts soit des théories naïves soit des théories scientifiques. L'éliminativisme à propos des concepts d'attitudes propositionnelles que je défends requière le second type d'élimination. Dans les trois chapitres suivants je donne trois arguments en faveur de cette thèse. Je commence par soutenir que la théorie interventionniste de la causalité ne fonde pas nos jugements de causalité mentale. Ensuite je montre que nos concepts d'attitudes propositionnelles ne sont pas des concepts d'espèces naturelles car ils groupent ensemble les états des différents modules d'une architecture massivement modulaire, la thèse de modularité massive faisant partie, je l'affirme, de notre meilleur programme de recherche. Finalement, mon troisième argument repose sur l’élimination du concept de contenu mental de nos théories. Dans les deux derniers chapitres de la thèse, je défends ce dernier argument. Tout d'abord, je réfute l'argument du succès selon lequel étant donné que les psychologues emploient le concept de contenu mental et ce faisant produisent de la bonne science ce concept ne devrait pas être éliminé. Ensuite je rejette une autre façon d'éliminer ce concept, celle choisie par les théoriciens de la cognition étendue. Pour cela je réfute le meilleur argument qui a été donné en faveur de cette thèse: l'argument du système. / In this dissertation, I argue for the elimination of propositional attitudes concepts. In the first chapter I sketch the landscape of eliminativism in contemporary philosophy of mind and cognitive science. There are two kinds of eliminativism: eliminative materialism and concept eliminativism. One can further distinguish between folk and science eliminativism about concepts: whereas the former says that the concept should be eliminated from our folk theories, the latter says that the concept should be eliminated form our scientific theories. The eliminativism about propositional attitudes concepts I defend is a species of the latter. In the next three chapters I put forward three arguments for this thesis. I first argue that the interventionist theory of causation cannot lend credit to our claims of mental causation. I then support the thesis by showing that propositional attitudes concepts aren't natural kind concepts because they cross-cut the states of the modules posited by the thesis of massive modularity, a thesis which, I contend, is part of our best research-program. Finally, my third argument rests on science eliminativism about the concept of mental content. In the two last chapters of the dissertation I first defend the elimination of the concept of mental content from the success argument, according to which as psychologists produce successful science while using the concept of mental content, the concept should be conserved. Then, I dismiss an alternative way of eliminating the concept, that is, the way taken by proponents of extended cognition, by refuting what I take to be the best argument for extended cognition, namely, the system argument.
367

Le lien réciproque entre musique et mouvement étudié à travers les mouvements induits par la musique / The reciprocal link between music and movement studied through music-induced movements

Peckel, Mathieu 15 December 2014 (has links)
La musique et le mouvement sont inséparables. Les mouvements produits spontanément lors de l'écoute musicale seraient le reflet d'un lien étroit entre le système perceptif et moteur. Ce lien est l'objet d'étude de cette thèse. Une première approche concernait l'impact des mouvements induits par la musique sur la cognition musicale. Dans deux études, nous montrons que bouger en rythme sur la musique n'améliore ni la rétention de nouveaux morceaux de musique (Etude 1) ni la rétention d'informations contextuelles relatives à leur encodage (Etude 2). Les résultats des ces deux études suggèrent la superficialité du traitement inhérent à l'expression des affordances musicales nécessaire à la production de mouvements induits par la musique dans la tâche motrice ainsi qu'un traitement moteur automatique de la musique indépendamment de la tâche. L'importance du groove musical a également été mise en évidence. Une deuxième approche concernait l'influence de la perception de rythmes musicaux sur la production de mouvements rythmiques. Notre troisième étude testait l'hypothèse selon laquelle les membres du corps seraient influencés de manière différente en fonction du tempo musical. Les résultats montrent que la tâche de tapping était la plus influencée par la perception de rythmes musicaux. Ceci serait dû à la nature similaire de la pulsation musicale et des mécanismes de timing impliqués dans le tapping ainsi qu'à des phénomènes de résonance motrice. Nous avons également observé la mise en place de certaines stratégies face à la tâche. L'ensemble de ces résultats est discuté à la lumière du lien entre perception et action, de la cognition musicale incarnée et des affordances musicales. / Music and movement are inseparable. The movements that are spontaneously procuded when listening to music are thought to be related to the close relationship between the perceptual and motor system in listeners. This particular link is the main topic of this thesis. A first approach was focused on the impact of music-induced movements on music cognition. In two studies, we show that moving along to music neither enhances the retention of new musical pieces (Study 1) nor the retention of the contextual information related to their encoding (Study 2). These results suggest a shallow processing inherent to the expression of musical affordances required for the production of music-induced movements in the motor task. Moreover, they suggest that music is automatically processed in a motoric fashion independantly of the task. Our results also brought forward the importance of the musical groove. A second approach focused on the influence of the perception of musical rhythms on the production of rythmic movements. Our third study tested the hypothesis that different limbs would be differentially influenced depending on the musical tempo. Results show that the tapping taks was the most influenced by the perception of musical rhythms. We argued that this would come from the similar nature of the musical pulse and the timing mecanisms involved in the tapping task and motor resonance phenomena. We also observed different strategies put in place to cope with the task. All these results are discussed in light of the link between perception and action, embodied musical cognition and musical affordances.
368

Quels apports des méthodologies issues de la psychologie cognitive pour comprendre le comportement alimentaire ? : impact d'un amorçage olfactif / How do methodologies from cognitive psychology contribute to the understanding of eating behaviour ? : impact of an olfactory priming

Gaillet-Torrent, Marie 02 December 2013 (has links)
Il est maintenant bien établi en psychologie qu’une part significative des comportements et des choix sont influencés par des processus non-conscients. Les comportements alimentaires n’échappent pas à cette règle. L’objectif de cette thèse consistait à adapter et utiliser des méthodologies et les avancées issues de la psychologie cognitive pour étudier les comportements alimentaires. A cette fin, un paradigme d’amorçage a été utilisé. L’amorçage repose sur le fait que la perception d’un stimulus (l’amorce), qu’elle soit consciente ou non, peut entrainer une modification du traitement d’un autre stimulus (la cible), et aboutir à une modification du comportement. Evolutivement et fonctionnellement étroitement liée à l’alimentation, l’olfaction s’avère être une modalité particulièrement intéressante pour l’étude d’effets d’amorçage implicites sur des comportements alimentaires. Quatre études ont été mises en place pour étudier les effets d’odeurs alimentaires sur des choix alimentaires et des consommations. Pour la première fois, nous avons apporté des preuves scientifiques montrant : (1) qu’une odeur de fruit non-consciemment perçue peut avoir un impact sur les intentions de choix et sur les choix en situation réelle de consommation chez des adultes « sains », les guidant vers plus de fruits ou légumes ; (2) qu’une odeur de viande diffusée peu de temps avant le déjeuner semblerait pouvoir augmenter la consommation du plat principal chez des personnes âgées atteintes de la maladie d’Alzheimer. L’ensemble de ces résultats vient appuyer l’idée que l’utilisation d’amorces (olfactives) alimentaires conduirait à l’obtention d’effets « amorce-spécifique » / It is now well established in psychology that a significant part of human behaviours and decision-making is influenced by unconscious processes. Eating behaviours do not escape to this rule. The aim of this thesis consisted in adapting and using methodologies and advances from cognitive psychology in order to study eating behaviours. To this end, a priming paradigm was used. This paradigm is based on the fact that the perception of a stimulus (the prime), whether it is consciously or unconsciously perceived, may modify the processing of another stimulus (the target), and have an impact on a subsequent behaviour. Evolutionarily and functionally closely related to food, olfaction represents a modality particularly interesting to study implicit priming effects on eating behaviours. Four studies have been carried out to study the effects of food odours on food choices and intake. For the first time, scientific evidences have been provided to reveal: (1) that non-consciously perceived fruity odours can impact intentions of choices and choices in a real situation of consumption in ‘healthy’ adults, guiding them toward more fruit and vegetables; (2) that an odour of cooked-meat, diffused before lunchtime, would seem to be able to increase the intake of the main course, in elderly people with Alzheimer's disease. Taken together, these results support the idea that the use of (olfactory) food primes would lead to priming effects ‘specific to the food cue’
369

Werden Symbole auf Wegweisern schneller und sicherer erkannt als verbale Zielangaben? / Are pictograms identified faster and more correctly than verbal targets on road signs? / Est-ce que des pictogrammes sont identifiables plus vite et plus correctement que des destinations verbales sur les panneaux de signalisation?

Ruf, Stefanie 27 January 2017 (has links) (PDF)
Verkehrsschilder gelten als das gängigste Mittel zur Regulation des Straßenverkehrs und der Kommunikation zu den Straßennutzer*innen. Die Fähigkeit eines Fahrers bzw. einer Fahrerin, ein Verkehrsschild zu verstehen, ist deshalb essentiell für die Verkehrssicherheit. Zahlreiche Studien zeigen allerdings, dass mit einem durchschnittlichen Verständnis zwischen 50 und 70% der Verkehrsschilder z.T. große Verständnisschwierigkeiten bei den Fahrer*innen vorliegen. Die Verwendung von Piktogrammen stellt eine Möglichkeit dar, um vereinfachte, auf das Wesentliche reduzierte standardisierte Informationen zu übermitteln. In Folge der Zunahme des Verkehrsvolumens über die letzten Dekaden haben viele Länder solche symbolischen Schilder eingeführt, um internationale Reisen dort zu erleichtern, wo Sprachdifferenzen Barrieren darstellen könnten. Die vorliegende Arbeit beschäftigt sich deshalb mit der Verbesserung von Beschilderungen im Straßenverkehr für in- und ausländische Fahrer*innen in Bezug auf Verständlichkeit, Korrektheit von Entscheidungen und Reaktionszeiten. Derzeit gibt es eine Fülle an Forschung zu Symbolen auf Warn- und Gebotsschildern, allerdings nicht auf Wegweisern. Ziel dieser Studie war es, einen Forschungsbeitrag zur Nutzung von Piktogrammen im Straßenverkehr und zur Verkehrssicherheit zu leisten. Dazu wurde in einem Reaktionszeitexperiment zum einen die gerichtete Hypothese untersucht, dass Piktogramme schneller und sicherer erkannt werden als verbale Zielangaben. Diese Hypothese konnte nicht bestätigt werden, stattdessen wurde ein gegenteiliger Effekt gefunden. Zum anderen wurde die gerichtete Hypothese untersucht, dass deutsche Muttersprachler*innen sowohl bei symbolischen als auch bei verbalen Zielangaben insgesamt schnellere Reaktionszeiten und mehr korrekte Antworten zeigen; dies konnte bestätigt werden. Unter Einbezug der Kovariaten Alter, Geschlecht und Fahrerfahrung zeigten sich besonders ein signifikanter Effekt des Alters und des Schildes, das die Versuchspersonen präsentiert bekamen; der zuvor noch gefundene Haupteffekt der Art der Zielangabe (symbolisch/ verbal) war dann nicht mehr signifikant. Mögliche Gründe werden abschließend diskutiert. / Road signs can be regarded as the most common means of traffic regulation and communication to road users. The driver’s ability to understand a road sign therefore is essential for traffic safety. However, a large body of research shows that – with a mean comprehension value that varies between 50 and 70% - drivers have difficulties in understanding the meaning of traffic signs. The use of pictorials represents one way of conveying simplified, standardized pieces of information. With the increase in traffic volumes over the last decades, a lot of countries have introduced such symbolic signs to facilitate international travelling where language differences constitute linguistic barriers. Currently, a variety of studies on symbolic warning and mandatory signs, but not on directory signs exists. The present study subsequently deals with the improvement of directory signs in road traffic for national and international drivers regarding comprehensibility, correctness of decisions and reaction times. The aim of this study is to contribute to existing research on the topic of use of pictorials in road traffic and on traffic safety. A reaction time experiment was developed and carried out with 101 participants aged 18 to 87. 63 of the test persons had acquired German as mother language; for 38 of the participants, German was not the native tongue. Each participant was presented with 32 German directory signs that had specially been developed for the experiment. Participants had to indicate the direction they would use to reach a certain predetermined target location that could either be represented verbally or as a symbol. Two hypotheses were tested: the first hypothesis stated that pictorials should be detected faster and more accurately than verbal targets. This could not be confirmed; instead, we found the opposite pattern. The second hypothesis assumed that German native speakers would show faster reaction times and a greater number of correct answers for symbolic as well as for verbal targets compared to non-native German speakers; this hypothesis could be confirmed. Including the covariates age, sex and driving experience, a very significant effect of age as well as of the specific sign that the subjects were presented with could be shown; the previously found main effect of target type (verbal/pictorial) was not significant, anymore. Finally, the present study discusses possible reasons and influencing factors for the observed effects like arrangement and number of targets on a sign as well as the word length of the used targets.
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Quel son spatialisé pour la vidéo 3D ? : influence d'un rendu Wave Field Synthesis sur l'expérience audio-visuelle 3D / Which spatialized sound for 3D video ? : influence of a Wave Field Synthesis rendering on 3D audio-visual experience

Moulin, Samuel 03 April 2015 (has links)
Le monde du divertissement numérique connaît depuis plusieurs années une évolution majeure avec la démocratisation des technologies vidéo 3D. Il est désormais commun de visualiser des vidéos stéréoscopiques sur différents supports : au cinéma, à la télévision, dans les jeux vidéos, etc. L'image 3D a considérablement évolué mais qu'en est-il des technologies de restitution sonore associées ? La plupart du temps, le son qui accompagne la vidéo 3D est basé sur des effets de latéralisation, plus au moins étendus (stéréophonie, systèmes 5.1). Il est pourtant naturel de s'interroger sur le besoin d'introduire des événements sonores en lien avec l'ajout de cette nouvelle dimension visuelle : la profondeur. Plusieurs technologies semblent pouvoir offrir une description sonore 3D de l'espace (technologies binaurales, Ambisonics, Wave Field Synthesis). Le recours à ces technologies pourrait potentiellement améliorer la qualité d'expérience de l'utilisateur, en termes de réalisme tout d'abord grâce à l'amélioration de la cohérence spatiale audio-visuelle, mais aussi en termes de sensation d'immersion. Afin de vérifier cette hypothèse, nous avons mis en place un système de restitution audio-visuelle 3D proposant une présentation visuelle stéréoscopique associée à un rendu sonore spatialisé par Wave Field Synthesis. Trois axes de recherche ont alors été étudiés : 1 / Perception de la distance en présentation unimodale ou bimodale. Dans quelle mesure le système audio-visuel est-il capable de restituer des informations spatiales relatives à la distance, dans le cas d'objets sonores, visuels, ou audio-visuels ? Les expériences menées montrent que la Wave Field Synthesis permet de restituer la distance de sources sonores virtuelles. D'autre part, les objets visuels et audio-visuels sont localisés avec plus de précisions que les objets uniquement sonores. 2 / Intégration multimodale suivant la distance. Comment garantir une perception spatiale audio-visuelle cohérente de stimuli simples ? Nous avons mesuré l'évolution de la fenêtre d'intégration spatiale audio-visuelle suivant la distance, c'est-à-dire les positions des stimuli audio et visuels pour lesquelles la fusion des percepts a lieu. 3 / Qualité d'expérience audio-visuelle 3D. Quel est l'apport du rendu de la profondeur sonore sur la qualité d'expérience audio-visuelle 3D ? Nous avons tout d'abord évalué la qualité d'expérience actuelle, lorsque la présentation de contenus vidéo 3D est associée à une bande son 5.1, diffusée par des systèmes grand public (système 5.1, casque, et barre de son). Nous avons ensuite étudié l'apport du rendu de la profondeur sonore grâce au système audio-visuel proposé (vidéo 3D associée à la Wave Field Synthesis). / The digital entertainment industry is undergoing a major evolution due to the recent spread of stereoscopic-3D videos. It is now possible to experience 3D by watching movies, playing video games, and so on. In this context, video catches most of the attention but what about the accompanying audio rendering? Today, the most often used sound reproduction technologies are based on lateralization effects (stereophony, 5.1 surround systems). Nevertheless, it is quite natural to wonder about the need of introducing a new audio technology adapted to this new visual dimension: the depth. Many alternative technologies seem to be able to render 3D sound environments (binaural technologies, ambisonics, Wave Field Synthesis). Using these technologies could potentially improve users' quality of experience. It could impact the feeling of realism by adding audio-visual spatial congruence, but also the immersion sensation. In order to validate this hypothesis, a 3D audio-visual rendering system is set-up. The visual rendering provides stereoscopic-3D images and is coupled with a Wave Field Synthesis sound rendering. Three research axes are then studied: 1/ Depth perception using unimodal or bimodal presentations. How the audio-visual system is able to render the depth of visual, sound, and audio-visual objects? The conducted experiments show that Wave Field Synthesis can render virtual sound sources perceived at different distances. Moreover, visual and audio-visual objects can be localized with a higher accuracy in comparison to sound objects. 2/ Crossmodal integration in the depth dimension. How to guarantee the perception of congruence when audio-visual stimuli are spatially misaligned? The extent of the integration window was studied at different visual object distances. In other words, according to the visual stimulus position, we studied where sound objects should be placed to provide the perception of a single unified audio-visual stimulus. 3/ 3D audio-visual quality of experience. What is the contribution of sound depth rendering on the 3D audio-visual quality of experience? We first assessed today's quality of experience using sound systems dedicated to the playback of 5.1 soundtracks (5.1 surround system, headphones, soundbar) in combination with 3D videos. Then, we studied the impact of sound depth rendering using the set-up audio-visual system (3D videos and Wave Field Synthesis).

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