Multiple views of control flows as a tool to improve programmer's understanding of interactive software

International audienceMy work addresses the question of how to improve programming notations and environments used for developing interactive systems. I focus on representing the control flow in interactive programs in the hope that it will improve the programmer?s ability to understand how their programs work. My thesis is that offering programmers the ability to create and manipulate multiple ad-hoc views of the control flow is the right way to go, where current programming languages and environment each choose one particular view

A Monocentric City With Discrete Transit Stations

We extend the monocentric model by considering a discrete number of accessible mass transit stations. Households combine two modes for their daily home-to-work trip: a first mode for terminal access to stations and a second (long haul) mode which consists in radial mass transit axes. The urban equilibrium, i.e. city size and households' distribution, is derived as a function of the mass transit network and the distribution of land housing capacity. Then at the urban equilibrium the land rent is peaked at transit stations and decreases with the travel cost from the city center rather than with the distance to it. Accordingly, the housing lot size increases with the travel cost from the city center. These features distinguish our framework from previous monocentric models. Our analysis is based on the assumptions that land-owners are absent and city is open (the households' level of utility is given and the population size is endogenous). For numerical illustration, the model is calibrated to a selected rail network in the Paris area. A sensitivity analysis of the urban structure and land-use equilibrium is conducted with respect to the key model parameters.

The influence of psychological distance on the effects of music congruency in consumer behavior

Specific music genres (classical, country/rock) are known to have a premium pricing effect on consumer’s purchase decisions. The induction of a temporal psychological distance variable in a purchasing process alters music congruity semantic priming effects on consumer behavior, since more psychologically distant objects are said to reduce priming effects. In harmony with these concepts, a quantitative method shows how psychological distance influences background music affects through social identity, utilitarian, and ambiguous (displaying both attributes) products exposure on consumer’s overall pricing and hedonic perception; and if a contextual consumer conditioning can possibly force the perception framing of a product, when a background music is congruent with it.Específicos géneros musicais (clássica, country/rock) são conhecidos por terem um efeito de preço premium no que diz respeito às decisões de compra dos consumidores. A indução de uma variável de distancia psicológica temporal no processo de compra altera os priming effects da coerência musical, uma vez que quanto maior a distancia psicológica dos objetos menor serão os priming effects. Quando ambos conceitos se encontram em harmonia, o estudo mostra como a distancia psicológica influencia o efeito que a música de fundo tem na identidade social, no utilitarismo, e por fim, a ambiguidade (quando ambos atributos estão presentes) que a exibição do produto tem na disponibilidade para pagar e na experiência hedónica do consumidor. Este estudo também procura compreender se o condicionamento contextual do consumidor pode forçar a percepção de enquadramento do produto, quando a música de fundo é coerente com efeito de distancia psicológica

Dimerization of ion radicals in ionic liquids. An example of favourable "Coulombic" solvation.

International audienceThe irreversible dimerization of the acetophenone radical anion, chosen as an example of a carbon-carbon coupling reaction between two charged species, was investigated in a series of 1,3-dialkylimidazolium and 1,2,3-trialkylimidazolium ionic liquids. Indeed, such ion dimerizations which display slow kinetics despite small activation energies, are controlled by a subtle competition between bond formation, Coulombic repulsion and solvation. The effects of viscosity, "polarity" and ionic solvation on the reactivity of the radical anions were examined. The dimerization rate constants were demonstrated to be only weakly affected by the high viscosity of the medium or its apparent polarity. When the acetophenone radical anion is "solvated" in imidazolium-based ionic liquids, a strong interaction between the negatively-charged intermediates and the imidazolium cation occurs. The ensuing charge stabilization allows a fast dimerization step in all the ionic liquids used. The kinetic effect is even enhanced in the 1,3-dialkylimidazolium salts as compared to the 1,2,3-trialkylimidazolium ones because the interaction between the radical anions and the 1,3-dialkylimidazolium cations are stronger, probably due to the formation of H-bond. The reactivity of the ion radical is demonstrated not only to be mainly dominated by electrostatic interactions, but also that the nature of the ionic liquid cations with respect to that of the ion radical is a major factor that affects the reaction kinetics

Étude des architectures des microprocesseurs MIPS R10000, UltraSPARC et PentiumPro

Aujourd'hui, les microprocesseurs rapides sont utilisés dans de nombreux systèmes matériels : stations de travail, multiprocesseurs, systèmes temps réel. .. L'évolution technologique est extrêmement rapide dans de nombreux domaines tels que l'intégration sur les circuits intégrés, la fréquence de fonctionnement ou l' architecture des microprocesseurs. Nous étudions dans ce rapport les microprocesseurs MIPS~R10000, Sun UltraSPARC et Intel PentiumPro. Ces trois microprocesseurs sont disponibles depuis le début 1996. Cette étude comparative, effectuée dans le cadre de l'activité de veille technologique du projet CAPS (Compilation, Architectures Parallèles, Systèmes), met en évidence les choix faits par les constructeurs de ces trois microprocesseurs et compare les diverses mises en oeuvre

Exploration et gestion des connaissances des ressources en IHM

National audienceNous présentons dans l' article le résultat d'un travail réalisé à l'école de Printemps 2010 de l'AFIHM. L'analyse des activités liées à la réalisation d' un état de l'art nous montre qu'une des tâches les plus compliquées est la familiarisation avec un nouveau domaine. Pour outiller cette activité, nous présentons des pistes de réflexion basées sur une analogie avec la mémoire humaine

Recurrent boosting effects of short inactivity delays on performance: an ERPs study

<p>Abstract</p> <p>Background</p> <p>Recent studies investigating off-line processes of consolidation in motor learning have demonstrated a sudden, short-lived improvement in performance after 5–30 minutes of post-training inactivity. Here, we investigated further this behavioral boost in the context of the probabilistic serial reaction time task, a paradigm of implicit sequence learning. We looked both at the electrophysiological correlates of the boost effect and whether this phenomenon occurs at the initial training session only.</p> <p>Findings</p> <p>Reaction times consistently improved after a 30-minute break within two sessions spaced four days apart, revealing the reproducibility of the boost effect. Importantly, this improvement was unrelated to the acquisition of the sequential regularities in the material. At both sessions, event-related potentials (ERPs) analyses disclosed a boost-associated increased amplitude of a first negative component, and shorter latencies for a second positive component.</p> <p>Conclusion</p> <p>Behavioral and ERP data suggest increased processing fluency after short delays, which may support transitory improvements in attentional and/or motor performance and participate in the final setting up of the neural networks involved in the acquisition of novel skills.</p