952 resultados para Hirsch, Samson RaphaelHirsch, Samson RaphaelSamson RaphaelHirsch
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Dans les modèles d’évaluation d’actifs financiers, la stratégie de placement d’un individu est liée à la distribution des rendements des actifs inclus dans son portefeuille. Le modèle intertemporel d’évaluation des actifs financiers basé sur la consommation (C-CAPM) permet d’intégrer la dimension temporelle dans le cadre d’analyse et de comprendre l’arbitrage entre les décisions de consommation et d’épargne d’un individu. La prédiction fondamentale de ce modèle est l’existence d’un lien entre les rendements des actifs financiers et leur covariance avec le taux marginal de substitution intertemporel (TMSI). Dans un cadre théorique, l’énigme de la prime de risque est mise en évidence lorsqu’une fonction d’utilité de type CRRA est utilisée afin de représenter les préférences du consommateur. La rigidité de cette modélisation impose cependant un coefficient d’aversion au risque fixe réconciliant difficilement le modèle avec les données réelles. Ce mémoire a pour objectif de résoudre cette problématique en modifiant les formulations classiques du TMSI. Dans un contexte canadien, nous modifions la forme CRRA afin de déterminer, entre autres, si les variations du produit intérieur brut ont un effet sur le niveau d’aversion au risque d’un agent. Par la suite, nous insérons la richesse immobilière dans une forme d’utilité non-séparable comme proxy du rendement de la richesse. Nos résultats suggèrent qu’il est pertinent, sur une longue période, de tenir compte de la richesse immobilière dans le programme de consommation de l’agent.
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Méthodologie: Modèle de Fama-French
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Dans le souci d’améliorer le réseau de distribution de l'énergie électrique, tout en maintenant l'intégrité de certains sites urbains protégés, plusieurs municipalités du Québec ont choisi d’enfouir leurs fils électriques. Ce type d’installation requiert des chambres de raccordement souterraines afin de réaliser l’entretien du réseau et le câblage. Ces chambres sont typiquement placées à tous les 300 mètres du réseau et sont généralement recouvertes d’épaisseurs de remblai allant de 0,6 m à 1m. L’un des principaux problèmes affectant l’état structural de ces chambres est la dégradation du béton de la surface externe de celles-ci. Dans certains cas, la dégradation peut atteindre une portion non négligeable de l’épaisseur de la dalle, jusqu’à en causer l’effondrement. En plus de présenter un danger pour la population, ces effondrements entraînent des coûts d’entretien élevés pour les propriétaires d’ouvrages. En outre, ces chambres sont difficiles à inspecter par l’intérieur. Cette problématique est d’autant plus importante étant donné la grande quantité de chambres de raccordement souterraines construites par le passé. Dans ce contexte, Hydro-Québec a lancé un programme de recherche visant à faire l'évaluation par des techniques de contrôle non destructif de l’état du béton du toit des chambres de raccordement souterraines. C'est dans ce cadre que s'inscrit cette étude. Le but de notre projet est d'évaluer les capacités de la technique du Géoradar à détecter l’endommagement du béton et, si possible, déterminer l’étendue en profondeur des dégradations dans le béton de ces dalles en béton armé enterrées. Ce mémoire de maîtrise présente la méthode proposée pour atteindre cet objectif. Des simulations numériques ont été réalisées, dans un premier temps, pour établir les limites de l'application Géoradar dans le cadre de notre problématique. Les résultats obtenus ont ensuite été confrontés à des essais réalisés sur des dalles réelles enterrées. Les travaux ont permis de montrer sans équivoque qu'avec le Géoradar, il est possible de déceler la dégradation au niveau des dalles enterrées, lorsque celles-ci se situaient à une profondeur maximale de 75 cm sous un sol de type sableux. Mais, il est encore difficile de pouvoir estimer l’étendue en profondeur de la dégradation, sans connaître l'état initial des dalles.
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O ciclo de vida de Spaethiella tristis (Boh.), um besouro que se alimenta de folhas de dende (Elaeis guineensis Jacq.), é de mais ou menos 56 dias, sob condicoes de laboratorio. Seus inimigos naturais, coletados de um plantio de dende na Estacao Experimental do Rio Urubu/CPAA, foram: Paecilomyces farinosus (Samson & Evans) e Metarhizium sp. parasitando larvas e adultos, respectivamente, e uma especie nao identificada de Chalcididae (Hymenoptera), parasitando larvas. O dano da folha causado por S. tristis é agravado pela infeccao do fungo Pestalotiopsis guepini (Desm.) Steyaert, que se instala nos ferimentos feitos pelo inseto.
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This workshop proposes to explore new approaches to cultivate and support sustainable food culture in urban environments via human computer interaction design and ubiquitous technologies. Food is a challenging issue in urban contexts: while food consumption decisions are made many times a day, most food interaction for urbanites occurs based on convenience and habitual practices. This situation is contrasting to the fact that food is at the centre of global environment, health, and social issues that are becoming increasingly immanent and imminent. As such, it is timely and crucial to ask: what are feasible, effective, and innovative ways to improve human-food-interaction through human-computer-interaction in order to contribute to environmental, health, and social sustainability in urban environments? This workshop brings together insights across disciplines to discuss this question, and plan and promote individual, local, and global change for sustainable food culture.
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Against a background of population aging, and with it, warnings about the sustainability of social welfare systems and problems associated with declining labour supply, there is an increasing policy emphasis on extending working lives of older workers among the industrialised nations (Hirsch, 2003; Keese, 2005; Taylor, 2006). However, recent commentaries have tended to focus on the relationship between population aging and the labour market, largely ignoring other critical factors that are affecting older workers’ relationship with the labour market. This contrasts with extensive research undertaken in the 1980s and 1990s when the forces acting upon older workers at that time were thoroughly elucidated (e.g. Kohli et al., 1991). The focus of this paper is on the labour supply challenges for employers and nations arising from demographic trends, in combination with social and technological changes and the wider forces of globalisation, how each is responding, and how these trends are affecting older workers’ trying to secure or maintain footholds in a labour market but facing, as Richard Sennett (2006) puts it, the ‘spectre of uselessness’ as jobs they could do have either migrated to other parts of the world or have been destroyed in the wake of industry failure.
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Norman K. Denzin (1989) claims that the central assumption of the biographical method—that a life can be captured and represented in a text—is open to question. This paper explores Denzin’s statement by documenting the role of creative writers in re-presenting oral histories in two case studies from Queensland, Australia. The first, The Queensland Business Leaders Hall of Fame, was a commercial research project commissioned by the State Library of Queensland (SLQ) in 2009, and involved semi-formal qualitative interviews and digital stories. The second is an on-going practice-led PhD project, The Artful Life: Oral History and Fiction, which investigates the fictionalisation of oral histories. Both projects enter into a dialogue around the re-presentation of oral and life histories, with attention given to the critical scholarship and creative practice in the process. Creative writers represent a life having particular preoccupations with techniques that more closely align with fiction than non-fiction (Hirsch and Dixon 2008). In this context, oral history resources are viewed not so much as repositories of historical facts, but as ambiguous and fluid narrative sources. The comparison of the two case studies also demonstrates that the aims of a particular project dictate the nature of the re-presentation, revealing that writing about another’s life is a complex act of artful ‘shaping’. Alistair Thomson (2007) notes the growing interdisciplinary nature of oral history scholarship since the 1980s; oral histories are used increasingly in art-based contexts to produce diverse cultural artefacts, such as digital stories and works of fiction, which are very different from traditional histories. What are the methodological implications of such projects? This paper will draw on self-reflexive practice to explore this question.
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Anna Hirsch and Clare Dixon (2008, 190) state that creative writers’ ‘obsession with storytelling…might serve as an interdisciplinary tool for evaluating oral histories.’ This paper enters a dialogue with Hirsch and Dixon’s statement by documenting an interview methodology for a practice-led PhD project, The Artful Life Story: Oral History and Fiction, which investigates the fictionalising of oral history. ----- ----- Alistair Thomson (2007, 62) notes the interdisciplinary nature of oral history scholarship from the 1980s onwards. As a result, oral histories are being used and understood in a variety of arts-based settings. In such contexts, oral histories are not valued so much for their factual content but as sources that are at once dynamic, emotionally authentic and open to a multiplicity of interpretations. How can creative writers design and conduct interviews that reflect this emphasis? ----- ----- The paper briefly maps the growing trend of using oral histories in fiction and ethnographic novels, in order to establish the need to design interviews for arts-based contexts. I describe how I initially designed the interviews to suit the aims of my practice. Once in the field, however, I found that my original methods did not account for my experiences. I conclude with the resulting reflection and understanding that emerged from these problematic encounters, focusing on the technique of steered monologue (Scagliola 2010), sometimes referred to as the Biographic Narrative Interpretative Method (Wengraf 2001, Jones 2006).
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This workshop is a continuation and extension to the successful past workshops exploring the intersection of food, technology, place, and people, namely 2009 OZCHI workshop, Hungry 24/7? HCI Design for Sustainable Food Culture and Sustainable Interaction with Food, Technology, and the City [1] and 2010 CHI panel Making Food, Producing Sustainability [3]. The workshop aims to bring together experts from diverse backgrounds including academia, government, industry, and non-for-profit organisations. It specifically aims to create a space for discussion and design of innovative approaches to understanding and cultivating sustainable food practices via human-computer-interaction (HCI) as well as addressing the wider opportunities for the HCI community to engage with food as a key issue for sustainability The workshop addresses environmental, health, and social domains of sustainability in particular, by looking at various conceptual and design approaches in orchestrating sustainable interaction of people and food in and through dynamic techno-social networks.
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Metrics such as passengers per square metre have been developed to define optimum or crowded rail passenger density. Whilst such metrics are important to operational procedures, service evaluation and reporting, they fail to fully capture and convey the ways in which passengers experience crowded situations. This paper reports findings from a two year study of rail passenger crowding in five Australian capital cities which involved a novel mixed-methodology including ethnography, focus groups and an online stated preference choice experiment. The resulting data address the following four fundamental research questions: 1) to what extent are Australian rail passengers concerned by crowding, 2) what conditions exacerbate feelings of crowdedness, 3) what conditions mitigate feelings of crowdedness, and 4) how can we usefully understand passengers’ experiences of crowdedness? It concludes with some observations on the significance and implications of these findings for customer service provision. The findings outlined in this paper demonstrate that the experience of crowdedness (including its tolerance) cannot be understood in isolation from other customer services issues such as interior design, quality of environment, safety and public health concerns. It is hypothesised that tolerance of crowding will increase alongside improvements to overall customer service. This was the first comprehensive study of crowding in the Australian rail industry.
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The migration of three human prostate tumor epithelial cell lines (TSU-pr1, PC-3, DU-145) in response to secreted protein from a human prostate stromal cell line was investigated by using the modified blind-well Boyden chamber assay. Migrated cells were quantified by spectrophotometrically measuring the concentration of crystal violet stain extracted from their nuclei. Cell number was correlated linearly with the concentration of extracted crystal violet stain. All three tumor cell lines showed intrinsic migratory ability in the absence of chemoattractants, such that approximately 1-7% of plated cells migrated across the filter of the Boyden chambers during a 5-h incubation period. Prostate tumor cell migration was significantly enhanced (3-13-fold) in response to stromal cell secretory protein in a dose-dependent manner, whereas bovine serum albumin had no effect on stimulating tumor cell migration. Immunoprecipitation of the stromal cell secreted protein with a nerve growth factor antibody partially and significantly reduced its stimulatory activity for tumor cell migration. A Zigmond-Hirsch matrix assay of tumor cell migration in response to various concentration gradients of stromal cell secreted protein demonstrated both chemotaxis and chemokinesis by all three cell lines. These results are consistent with the stromal cell secretory protein stimulation of chemokinetic tumor cell migration through the capsule of the prostate. Outside of the prostate gland metastasis of tumor cells may occur by chemotaxis to preferential sites containing chemoattractants similar to or related to maintenance factors that can substitute for components of stromal cell secretory protein.
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Dissociable processes for conscious perception (“what” processing) and guidance of action (“how” processing) have been identified in visual, auditory, and somatosensory systems. The present study was designed to find similar dissociation within whole-body movements in which the presence of vestibular information creates a unique perceptual condition. In two experiments, blindfolded participants walked along a linear path and specified the walked distance by verbally estimating it (“what” measure) and by pulling a length of tape that matched the walked distance (“how” measure). Although these two measures yielded largely comparable responses under a normal walking condition, variability in verbal estimates showed a qualitatively different pattern from that in tape-pulling when sensory input into walking was altered by having participants wear a heavy backpack. This suggests that the “what” versus “how” dissociation exists in whole-body movements as well, supporting a claim that it is a general principle with which perceptual systems are organized.
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This study focuses on two philosophical issues related to the interpretation of art. Firstly, it considers the role of authorial intentions in interpretation. Secondly, the study raises the issue of relativism in interpretation through a discussion of the relativistic tendencies apparent in the views of three major figures of contemporary philosophy: Joseph Margolis, Hans-Georg Gadamer, and Richard Rorty. The major goal of the thesis is to develop a theory of interpretation supporting the role of authorial intentions in interpretation on the basis of Donald Davidson s late philosophy of language and the holistic account of interpretation that underlies different parts of his philosophy. It is my belief that an intentionalist view of interpretation built on Davidsonian elements manages to form the most convincing defense of that interpretive position against the skepticism present in the views of Margolis, Gadamer, and Rorty. The theoretical issues addressed in the thesis are illuminated by discussions of case-examples, most importantly Richard Wagner s The Valkyrie, Thomas Adés America: A Prophecy, and some symphonies by Dimitri Shostakovich. In chapter one, I present a critical discussion of Margolis robust relativism. While finding Margolis criticism of the self-refutive argument plausible, I, nevertheless, argue that the relativistic logic Margolis offers should not be favored in interpretation. The first parts of chapter two outline Davidsonian intentionalism by presenting a reading of Davidson s later work in philosophy of language and mind, and by indicating its relationship to Davidson s views of literature. Then, I shall compare Davidson s ideas with some recent modest forms of intentionalism found in analytic aesthetics, and argue that Davidsonian intentionalism is in many respects more satisfactory compared to them. Chapter three engages Gadamer s hermeneutics by defending E.D. Hirsch s criticism of Gadamer. Uncovering the shortcomings in the replies of Gadamer s followers to Hirsch s criticism serves as a basis for the defense of intentionalism in interpretation carried out in the chapter. That defense is then extended with a discussion of some recent hermeneutic readings of Davidson s views. Chapter four deals with the standing of intentionalism through Rorty s pragmatist approach to literature. By indicating the position of pragmatist notions of aesthetic experience and imagination in Davidsonian intentionalism, it is shown that an intentionalist approach need not be as impoverished with regard to the value Rorty attributes to literature as he assumes. The concluding chapter outlines some ways in which one can be a pluralist with regard to art and interpretation without falling into relativism.