Abstract concepts seem to be related to space dimension. Evidence of this relation refers to the domain of numerical cognition. An example is the SNARC effect (Spatial Numerical Association of Response Codes, Dehaene, Bossini, and Giraux 1993), which consists in the observation that people react faster to small number with the left hand and to large number with the right hand. This number-space interaction has been explained according to the mental number line hypothesis (e.g. Restle 1970; Dehaene, Bossini, and Giraux 1993), which claims that the representation of numbers has the form of a horizontal line upon which numbers are represented from left to right. Recently, an alternative account suggests that the association between numbers and space results from a decision process to categorize numbers as “small” and “large” before being associated with space dimension (e.g. Gevers et al. 2006b, 2010; Van Opstal and Verguts 2013). The first goal of this thesis is investigating the spatial coding of numbers. In a first study, magnitude concepts such as “small” and “large” were observed to be spatially organized like numbers. In a second study, these magnitude concepts were intermixed with numbers in a reversal design (e.g. Notebaert et al. 2006). In this study, responding as incompatible to magnitude concepts with hand or foot was observed to reverse the spatial mapping of numbers, supporting the idea that the congruency between numbers and space results from conceptual coding of magnitude (e.g. Gevers et al. 2006b, 2010; see also Van Opstal and Verguts 2013). Further evidence of association between abstract concepts and space has been provided also in the domain of emotion. On one hand, Casasanto (2009a) demonstrated that people spontaneously associate positive valence with the side of space congruent to the dominant hand. On the other hand, Holmes and Lourenco (2011) observed that emotional expressions are left-to-right spatially organized with increasing in happiness/angriness rather than positive/negative valence. A second aim of this thesis is focused on investigating the spatial coding of emotion. This was meant to understand how general are the spatial mechanisms. In a third study, the reversal paradigm (e.g. Notebaert et al. 2006) was adopted to investigate the processing mechanism underlying spatial coding of numbers and emotional valence concepts. Manipulation of the mapping between valence concepts and lateralized responses did not influence the spatial coding of numbers, suggesting a separate underlying architecture. Finally, in a fourth study, spatial coding of emotion was observed according to both valence and arousal dimensions (Casasanto 2009a; Holmes and Lourenco 2011). / Doctorat en Sciences psychologiques et de l'éducation / info:eu-repo/semantics/nonPublished

Language is one of the main means of acquiring information about the world. An important debate in social psychology, linguistics and philosophy is how we come to believe information contained in statements we hear and read. Are we capable of assessing it and filtering it out, in case it is erroneous? Or do we rather tend to believe it? The experimental studies described in this thesis suggest that we strongly tend to believe statements we hear and read, even if we are aware of their falsity. Truth bias, as this tendency has been called, was detected both at the level of people’s memory and at the level of their judgments. Specifically, in a fake judicial context participants who read or listened to statements explicitly designated as true or false about a perpetrator tended to misremember false statements as true. Additionally, they were influenced by the false statements’ content in judgments they made about the perpetrators. Chapter 1 encompasses 5 Studies, all pointing to a strong truth bias, that, contrary to what is often assumed, may operate even in the absence of increased cognitive load (Studies 1–2). Studies 3–5 in Chapter 1 were methodologically-oriented, primarily aimed at testing the validity of the generalized truth bias established in Studies 1–2. Chapter 2 examines potential vigilance triggers that may reduce the truth bias. Manipulating the source of the false information (by informing participants that the speaker is either a defense attorney or prosecutor; Study 1), rendering participants accountable for their judgments (Study 2) or asking real judges to accomplish our experimental task (Study 3) did not reduce the truth bias. Nevertheless, offering participants financial incentives for providing an accurate judgment, eliminated both the memory-based and the judgment-based truth bias (Study 4). Based on the present experimental findings, I develop a model predicting that the truth bias is an intrinsic element of linguistic communication and hard to override. / Doctorat en Sciences psychologiques et de l'éducation / info:eu-repo/semantics/nonPublished

La texturation de surface est une thématique récente qui suscite un certain engouement pour les contacts dynamiques. Pendant de nombreuses années, les tribologues ont privilégié les surfaces lisses aux faibles rugosités pour limiter le frottement. Inspiré des rugosités de surface organisées observées dans la nature, les topologies de surfaces sont désormais axées sur la texturation et la structuration des rugosités. Fort de ce potentiel, de nombreuses études traitent, par une approche numérique, la modélisation de ces surfaces et les études expérimentales sont rares, avec une instrumentation souvent insuffisante pour appréhender tous les phénomènes physiques. Par une approche expérimentale, nous analysons le comportement des butées hydrodynamiques à faces parallèles partiellement texturées. Les 80 capteurs équipant le dispositif d'essais permettent d'apprécier avec rigueur la phénoménologie à l'interface du patin et du film lubrifiant. L'analyse met l'accent sur la capabilité de ce composant à être intégré dans un environnement industriel. Afin d'objectiver les résultats, les campagnes d'essais sont menées sur dix butées hydrodynamiques dont quatre sont munies de texturation. Une comparaison de ces butées facilite leur classement en termes de capacité de charge, de réduction de frottement ou encore de risque d'usure dans les phases de démarrage. Pour les configurations étudiées, les butées texturées ne peuvent concurrencer les butées à poches ou à plans inclinés du point de vue de la capacité de charge. En se référant à une butée à faces parallèles, les butées texturées permettent une réduction du frottement de 30% à faibles charges tandis que pour de fortes charges, les / Surface texturing is a recent topic which has raised a great interest in contact dynamics. For many years, engineers have favored smooth surfaces with low roughness in order to minimize friction losses. Inspired by textured surfaces which can be commonly found in nature, the research in surface topography is now focused on texturing and roughness characterization. Considering the great potential of surface texturing, many research studies analyze this subject, most commonly theoretically, while experimental works are often performed with inadequate equipment which does not allow a proper evaluation of the involved physical phenomena. This study uses an experimental approach in order to analyze the behavior of hydrodynamic thrust bearings with parallel textured pads. The experimental device is equipped with 80 sensors which allow a proper assessment of the phenomenology at the film/pad interface. This analysis focuses on the capability of this textured component to be integrated in an industrial environment. To objectify the results, the tests are conducted on ten hydrodynamic thrust bearings, among which four are textured. The comparison between the performances of these bearings facilitates their classification in terms of load-carrying capacity, friction loss and wears resistance during the start-up period. Results show that for the studied configurations, the textured thrust bearings cannot compete with pocketed or tapered land thrust bearings in terms of load-carrying capacity. In the case of parallel thrust bearings, surface texturing can help to reduce friction up to 30% at low loads while for heavy loads, their performance is equivalent or even lower than that of

Doctorat en sciences psychologiques / info:eu-repo/semantics/nonPublished

Doctorat en sciences psychologiques / info:eu-repo/semantics/nonPublished

Doctorat en sciences psychologiques / info:eu-repo/semantics/nonPublished

Doctorat en sciences psychologiques / info:eu-repo/semantics/nonPublished

Doctorat en sciences psychologiques / info:eu-repo/semantics/nonPublished

Les besoins énergétiques du monde entier augmentent de plus en plus et parmi les sources en énergie renouvelable, l'énergie solaire connaît actuellement un très fort développement. Une des voies en énergie solaire est la filière utilisant des panneaux solaires hybrides qui produisent à la fois de l'électricité et de la chaleur. Le marché des capteurs hybrides en présence ou non de concentrateur et leurs caractéristiques sont présentés. Dans la thèse, on a étudié un capteur hybride associé avec un concentrateur holographique du rayonnement solaire. Ce concentrateur permet de séparer la partie visible utilisée par les cellules photovoltaïques de celle infrarouge, absorbée par l'échangeur thermique. Les différents éléments du capteur et leur fonctionnement sont décrits. Les caractéristiques du capteur et son efficacité dépendent des paramètres optiques et thermiques de ses éléments. Ces paramètres (facteurs de transmission, de réflexion, d'absorption, émissivité) ont été déterminés expérimentalement (CERTES IUT Sénart, CEMHTI Orléans, Université Blaise Pascal Clermont-Ferrand). Les résultats obtenus ont été utilisés dans une modélisation stationnaire et monodimensionnelle des échanges thermiques pour deux configurations différents (avec deux plaques en polycarbonate et avec une plaque en polycarbonate et une lame d'air). La modélisation introduit les effets radiatifs, conductifs et l'absorption du rayonnement en volume. Les profils thermiques et les rendements électriques et thermiques obtenus montrent l'efficacité d'un capteur solaire hybride avec concentrateur holographique. / The energy requirements worldwide are increasing more and among renewable energy sources, solar energy is exhibiting a very strong growth. Solar hybrid panels that produce both electricity and heat is currently a very promising way. The market for hybrid solar panel with and without concentrator and their characteristics are presented. In the thesis, a hybrid solar panel associated with a holographic concentrator solar radiation is studied. This concentrator separates the visible range used in the photovoltaic cells of the infrared range absorbed by the heat exchanger. The elements of the panel are described. The sensor characteristics and effectiveness depend on the optical and thermal parameters of its elements. These parameters (transmission factors, reflection, absorption, emissivity) were determined experimentally (CERTES IUT Sénart, CEMHTI Orleans, University Blaise Pascal Clermont-Ferrand). The results were obtained in a stationary and dimensional modelling heat exchanges for two different configurations (with two polycarbonate plates with a polycarbonate plate and an air). The model introduces radiative effects, conduction and radiation absorption by volume. The thermal profiles, and electrical and thermal efficiencies obtained show the effectiveness of a hybrid solar collector with holographic concentrator.

Cette thèse explore l’impact des technologies de l'information et de la communication (TIC) sur le comportement des employés. Alors que la théorie néoclassique de la croissance considère les TIC comme un outil utilisé dans le processus de production, nous nous sommes basé sur une théorie qui stipule que les technologies ont deux aspects différents. Les technologies de la communication centralisent la prise de décision tandis que les technologies de l'information déplacent la prise de décision au niveau de l'employé. Nous avons abordé les questions du meilleur type de technologie pour l’amélioration de la performance des employés, des coûts engendrés par l'utilisation de ce type de technologies et de l’impact de la surveillance informatique dans la réduction de ces coûts. Nous avons utilisé la méthode expérimentale pour répondre à ces questions. Nos résultats montrent que les employés préfèrent utiliser les technologies de l'information et ceux qui les utilisent sont plus productifs que les autres. Nous trouvons également que l’environnement de travail et les technologies qui poussent la prise de décision au niveau de l'employé pourraient engendrer des coûts importants pour l’entreprise. Cependant, la surveillance informatique est efficace pour réduire ces coûts mais son effet diminue au fil du temps. Nos résultats montrent que les employés les plus productifs sont ceux qui ont passé le plus de temps sur internet. Donner aux employés les informations constantes et détaillées (sur leur performance) produites par les technologies pourrait être une façon efficace de les sensibiliser sur l’ampleur de la surveillance informatique afin de les rendre plus performants. / This dissertation explores the impact of the use of Information and Communication Technologies (ICT) on employees’ behaviors. While the neoclassical growth theory considers ICT as an input used in the production process, we relied on a literature in the organizational economic field which states that technologies have two different key aspects. Information technologies push down the decision making at the employee level while Communication technologies centralize the decision making. We addressed the issue of the more efficient technologies for workers’ performance, the costs generated by using the most efficient type of technologies and how the technology-based monitoring may be useful to reduce those costs. We used the experimental methodology since the collection of individuals and team's production is hard with survey data. Our results show that employees prefer information technologies and those who use it are more productive than others. We also show that work organization and technologies which push down the decision making at the employee level could entail some substantial costs for the firm. Indeed, employees are more willing to engage on time wasting activities in order to influence the principal’s decision when they can participate to the decision making process. However IT monitoring is quite successful at reducing those costs. Technology monitoring implies a disciplining effect at the beginning when the sanction is available but this effect lessens over time. Our results show that employees are more productive when they spend more time on internet. Giving constant heightened feedbacks provided by ICT to employees about their productivity should be the better way to sensitize them about the extent of technology monitoring in order to increase their performance.