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Many online platforms rely on users to voluntarily provide content. What motivates users to contribute content for free, however, is not well understood. In this paper, we use a revealed-preference approach to show that career concerns play an important role in user contributions to Stack Overflow, the largest online question-and-answer community. We investigate how activities that can enhance a user’s reputation vary before and after the user finds a new job. We contrast this reputation-generating activity with activities that do not improve a user’s reputation. After finding a new job, users contribute 23.7% less in reputation-generating activity; by contrast, they reduce their non–reputation-generating activity by only 7.4%. These findings suggest that users contribute to Stack Overflow in part because they perceive such contributions as a way to improve future employment prospects. We provide direct evidence against alternative explanations such as integer constraints, skills mismatch, and dynamic selection effects. This paper was accepted by Chris Forman, information systems.

Cet article se propose d’analyser l’évolution de l’imaginaire informatique entre la fin des années 80 et les années 2010 au travers de l’étude de deux mondes fictionnels de jeu de rôle appartenant au genre du cyberpunk : Cyberpunk et Shadowrun. Après une rapide présentation de ces deux mondes fictionnels, il se livre dans un premier temps à l’étude des évolutions de l’imaginaire informatique constatées entre les différentes éditions de ces jeux afin de souligner deux idées importantes : la révolution que constitue un monde informatique sans fil et le paradoxe entre une démocratisation et une complexification de l’informatique. Dans un second temps, il s’efforce de dégager les grandes permanences de cet imaginaire informatique en montrant qu’il se cristallise autour des notions de capitalisme, de puissance, de violence et d’une étrange similitude entre magie et informatique. This paper aims to study how computer imaginary evolved from the end of the eighties until our days. To achieve this, we’ll scrutinize two famous cyberpunk pen and paper role playing game’s fictional worlds : Cyberpunk and Shadowrun. After a short description of those fictional worlds, we’ll study how computer imaginary evolved through the many editions of those RPG to emphasize two main ideas : the revolution of wireless hardware and the paradoxical democratization and complexity of computers. After which, we’ll show the permanence and consistency of some notions and representations : how computers are linked to capitalism and the idea of power or violence, and how computers are often related to the idea of magic.

TEC - Travaux en Cours; International audience; Multi-display environments (MDE) are becoming more and more common in public areas. They are mainly used to display information due to the limited interaction possibilities they offer. In this paper, we study how using everyday objects, available on or around users, could improve interaction with public multi-display environments. To this end, we conducted a study, in the form of a creativity session, to understand how participants would use everyday objects, to realize the most usual tasks in public MDEs. The results of this study are presented and discussed in this paper.; Les environnements multi-écrans (EME) se multiplient dans les lieux publics. Les possibilités d’interaction qu’ils offrent étant limitées, ils sont principalement utilisés pour afficher de l’information. Dans cet article, nous étudions comment les objets du quotidien, disponibles sur ou autour des utilisateurs, pourraient porter l’interaction avec les environnements multi-écrans publics. Cette approche fait émerger des solutions pour des interactions rapides, opportunistes et naturelles, ce qui répond aux besoins liés à ce type d’environnements (publics et peu sécurisés). Nous avons réalisé une séance de créativité à laquelle ont participé 8 personnes. Le but de cette séance était d’étudier la manière avec laquelle les participants exploiteraient différentes catégories d'objets du quotidien pour réaliser plusieurs tâches d’interaction avec des EME.

International audience; This paper introduces the Halphen distribution family for modeling travel time distributions and their reliability on single road links. This probability family originally used in hydrology has a set of relevant characteristics. It is composed of three probability distribution functions for which the mathematical properties are described here. The paper uses a graphical representation, the δ-Moment Ratio Diagram (δ-MRD). This tool allows characterizing travel time reliability as well as selecting best distribution candidates within the fitting processes, by considering empirical data sets. A systematic methodology is developed to take advantage of both aspects. From maximum log-likelihood estimation it is shown that Halphen distributions are amongst the best state-of-the-art solutions for the travel time modeling purpose. This global framework is validated using two empirical data sets: an urban data set gathered in Portland, Oregon (USA) and a periurban data set from Lyon (France). The model calibration is eased through the use of the δ-MRD; this property opens new research directions about the mapping between traffic states and statistical modeling. It comes out from all these considerations that the Halphen family is suitable to describe accurately the travel time dynamics on single links. Therefore it could be part of a decision support system for practitioners interested in travel time variability.

Purpose – The purpose of this paper is to present how to model moral sensitivity and emotions in organizational setting by using the SocLab formal framework. SocLab is a platform for the modelling, simulation and analysis of cooperation relationships within social organizations – and more generally Systems of Organized Action. Design/methodology/approach – Simulation results, including an interesting tendency for a Free Rider model, will be given. Considering that actors’ decision-making processes are not just driven by instrumental interest, the SocLab learning simulation algorithm has been extended to represent moral sensitivity, making actors trying to prevent bad emotions and feel good ones. Findings – Some simulation results about actors’ collaboration and emotions in a Free Rider model were presented. A noteworthy tendency is that actors’ unconditional collaboration, which occurs when their moral sensitivity reaches its highest value, is not so good since it exempts other actors from collaboration (they take advantage from the unconditional collaboration), while values of moral sensitivity somewhat below the highest value (between 0.7 and 0.9) still induces collaboration from others. Originality/value – The research and results presented in this paper have not been presented in other papers or workshops. The presented quantitative definition of emotions (determining indexes of emotions) is different to previous approaches – for instance, to Ortony, Clore and Collins (OCC) qualitative descriptions and to logical descriptions. Similarly, simulation of morality in organizations is a new research field, which has received scarce attention up to now.

National audience; Research contributions to improve interactive systems reliability as, for now, mainly focused towards fault occurrence prevention by removing software bugs at development time. However, Interactive Systems complexity is so high that whatever efforts are deployed at development time, faults and failures occur at operation time. Root causes of such failures may be due to transient hardware faults or (when systems are used in high atmosphere) may be so called "natural faults" triggered by alpha particles in processors or neutrons from cosmic radiations. This paper proposes an exhaustive identification of faults to be handled in order to improve interactive systems reliability. As currently no research has been carried out in the field of interactive systems to detect and remove natural faults, this paper proposes a software architecture providing fault-tolerant mechanisms dedicated to interactive systems. More precisely, the paper how such architecture addresses the various component of interactive applications namely widgets, user application and window manager. These concepts are demonstrated through a case study from the domain of interactive cockpits of large civil aircrafts. \; La recherche pour améliorer la fiabilité des systèmes interactifs s’est, pour l’instant, principalement dirigée vers la prévention d’introduction de fautes par la suppression des bugs lors du développement. Cependant, la complexité des systèmes interactifs est telle que, quels que soient ces efforts, des défaillances apparaissent lors de leur utilisation. Les causes de telles défaillances peuvent être dues à des pannes matérielles intermittentes ou (quand ces systèmes sont utilisés en haute altitude (avions, véhicules spatiaux …) être déclenchées par des fautes naturelles dues aux particules alpha dans les processeurs ou aux neutrons issus des radiations cosmiques. Cet article propose l’identification exhaustive des problématiques se posant pour améliorer la fiabilité des systèmes interactifs en prenant en compte à la fois les erreurs faites dans les phases de développement et les fautes qui peuvent se produire lors de leur utilisation. Du fait qu’aucune recherche n’a été menée à ce jour pour détecter et éliminer les fautes naturelles, l’article propose aussi une architecture logicielle pour intégrer des mécanismes de tolérance aux fautes dans les systèmes interactifs. L’article présente en particulier comment cette architecture couvre les différents composants d’un système interactif incluant les widgets, le gestionnaire de fenêtres et l’application interactive. Ces concepts sont mis en œuvre sur une application interactive de cockpits d’avions civils.

Within the last two decades, text messaging by means of SMS has become a central tool of communication around the globe. The use of more than one language for composing a message is wide spread, but, to this day, is relatively underrepresented in research. This paper presents an analysis of the plurilingual nature of SMS communication in Switzerland with the limelight on the forms and functions of code-switching within a set of 345 messages, base language of which is French. Results show that SMS users regularly exhibit code-switching even if they are not members of a bilingual speech community. Code-switching most frequently consists of inserts, i.e. embeddings of single items or combinations of items within a message composed in another language, and this typically involves (only) a limited range of routinized expressions. While English is the most frequently used language for code-switching, German, Swiss German, Spanish and Italian are also recurrent, the latter two being particularly associated with terms of endearment. Code-switching regularly highlights the expression of actions that have a strong interpersonal (phatic) focus, such as greetings, good-byes or thanks. It elucidates the expressive character of the messages, and is also associated with the expression of affection. The specificity of the plurilingual SMS repertoire is discussed in the paper's conclusion.

National audience; In real world scenarios, the formation of consensus is an self-organisation process by which actors have to make a joint assessment about a target subject being it a decision making problem or the formation of a collective opinion. In social simulation, models of opinion dynamics tackle the opinion formation phenomena. These models try to make an assessment, for instance, of the ideal conditions that lead an interacting group of agents to opinion consensus, polarisation or fragmentation. In this paper, we investigate the role of social relation structure in opinion dynamics using an interaction model of relative agreement. We present an agent-based model that defines social relations as multiple concomitant social networks and apply our model to an opinion dynamics model with bounded confidence. We discuss the influence of complex social network topologies where actors interact in multiple relations simultaneously. The paper builds on previous work about social space design with multiple contexts and context switching, to determine the influence of such complex social structures in a process such as opinion formation.

International audience; Several separate displays are used by Air Traffic Controllers, such as radar view, flight lists view or paper strips. In order to link the information between these views and keep focus on a subset of flights, controllers are required to do visual operations (eye gaze, analysis of visual properties etc.). This process can be disruptive when traffic increases and when visualizations display large amounts of objects. In this paper we propose the use of animated transitions to replace the visual paths controllers take. We discuss this technique and show results of a predictive evaluation that suggests an improvement in users' performance.

International audience; Initially designed in the nineteen seventies as a mere zapping tool, obviously the traditional device known as the TV remote control no longer responds to the multifarious needs of today's interactive television. Designing new remote-control devices is a challenge that the HCI community has started to face. The paper indicates the various directions that are currently being investigated by researchers. The paper starts with an attempt to characterize the specific context of interactive TV. We then offer a tentative account of the design and evaluation space of interest. There is little doubt that the traditional remote control may still be improved and augmented. It is unlikely, however, that it will survive for long the crisis it has been undergoing since the beginning of the digital era, given the emerging plethora of alternative interaction possibilities based on a variety of new interfacing logics, which the paper reviews.

Evaluating information retrieval implies a document collection on which search is carried out, a set of test queries and the lists of the relevant documents for each query. This evaluation framework also includes evaluation measures making it possible to control the impact of search parameters on the performance. Trec-eval calculates a large number of measures, some being used more widely, like the mean average precision or recall-precision curves. The aim of this paper is to choose the minimal set of measures necessary to compare different information retrieval systems. In this paper, we present the study we carried out on relationships between 27 measures among the most used in the literature. We show that a set of 7 measures is enough to represent 27 studied measures: ircl_prn.80, MAP, ircl_pr.20, recip_rank, P15, exact_precision, and exact_recall.

International audience; This paper presents a design space based on a morphological analysis of menu techniques. The goal of this design space is to facilitate the exploration of novel menu designs, in particular to increase menu capacity without sacrificing performance. The paper demonstrates the generative aspect of this design space with four new menu designs based on poorly explored combinations of input dimensions. For two of these four designs, the paper presents controlled experiments that show that they perform on a par with other menus from the literature.; Cet article présente un espace de conception basé sur une analyse morphologique des mécanismes de structuration des menus et de sélection des items. Son but est de faciliter l'exploration de nouveaux types de menus afin notamment d'augmenter leur capacité sans détériorer leurs performances. L'article démontre l'aspect génératif de cet espace de conception grâce à quatre nouveaux designs de menus, basés sur des combinaisons de dimensions pas ou peu explorées. Pour deux d'entre eux, des expérimentations contrôlées montrent qu'ils offrent des performances comparables aux menus de la littérature.

Three studies evaluate rewritings by students from 8 to 12 years old who used a resource texts database. This paper stresses the importance of the semantic treatment in the processes of writing and rewriting, describes the rewriting assistance system, and introduces to some important results. The students who use the system rewrite more, add macrostructure propositions and produce original propositions rather than propositions borrowed from the resource texts; the system helps the unskilled writers; access to the resource texts by criteria is more helpful than free navigation; the students who learned how to rewrite with the computer system succeed in better using the paper resource texts and transfer their skills to other text genres., Les trois expériences rapportées dans cet article ont pour but d'évaluer les effets d'une base de données textuelles, le logiciel expérimental Scripertexte, sur la révision et la réécriture de récits chez des élèves de huit à douze ans. La première expérience mesure les effets de ce dispositif sur l'amélioration des textes. La deuxième compare les effets de deux modes de navigation dans le logiciel. La troisième cherche à évaluer les apprentissages après trois ans d'utilisation de l'outil.

National audience; In the last few years, many works have been done in order to ensure interoperability between applications. Enterprise applications integration and the opening of information systems towards integrated access have been the main motivation for the interest around systems interoperability. In this Paper, an MDA based approach for interoperability is proposed. The MDA is an approach for systems development, which increases the power of models in that work. It provides a means for using models for better understanding, designing, constructing, deploying, operating, maintaining and modifying systems. The three primary goals of MDA are portability, interoperability and reusability. In this paper we apply the MDA as a formal base that supports our approach for interoperability between different information systems

cote interne IRCAM: Rioux01a; None / None; National audience; This paper presents two exploratory experiments aimed at establishing a lexicon suitable for the description of the sound quality of flue organ pipes. A lexicon of reference was established by an expert organ-builder commenting several voicing steps performed on a flue pipe. This lexicon was then extended, the purpose being primarily to enhance communication between and among organ builders, acousticians and musicians. In the first experiment a qualitative analysis was made of data collected from a listening test in which a number of specialists on organ performance, music theory, history and building took part. The 40 participants made ratings and gave comments to ten recordings of pipe sounds through the voicing process. By comparing an analysis of participants’ comments with a primary list of descriptors defined by an organ builder, an attempt is made to extend this primary list to a more standard lexicon. A temporary classification of these descriptors is proposed and is reviewed in a companion paper oriented towards a quantitative analysis of this type of data. In a second experiment, a dimensional analysis of data collected from a semantic differential test based upon the descriptors found in Experiment 1. From a quantitative analysis the initial "qualitative" categorisation is reviewed and enhanced. By inspecting the factor structure of the descriptors, groups of related descriptors were formed and suitable prototypes of each group were proposed. We then show how, from original data extracted from free comments, a detailed classification of descriptors can be made.

This paper puts forward a new methodology to characterize and compare the examination practice of patent offices. The methodology codifies public information into a typology of chronological key ex...

In this paper, we develop a new method of identification of complex prepositions, in French. We include well-known semantic and morpho-syntactic tests, and introduce a few others – together, these tests make up a multi-variable grid which we believe can help identify complex prepositions. We run these tests on a list of 75 sequences, most of which are considered to be complex adpositions. We also include sequences which share the same patterns of word formation but do not have prepositional uses, in order to check the validity of our grid. Our results show that the semantic and morpho-syntactic clues used to identify complex adpositions, combined with corpus data exploration, are on the whole quite effective, but to varying degrees depending on the pattern of formation.

International audience; This paper aims at better understanding the transition from menus to shortcuts. We first discuss the limitations and the opportunities of the theoretical and empirical characterizations of this transition. We then consider keyboard shortcuts as a case study and manually annotate empirical data to estimate several behavioral markers such as the initial switch, the transition duration or the performance dip. These markers serve to precisely characterize and compare three interaction techniques. Finally, we compare two methods to automatically characterize the transition from menus to shortcuts.; Ce papier vise à mieux comprendre la transition des menus vers les raccourcis. Nous discutons d’abord les limitations et les opportuni- tés des caractérisations, théoriques et empiriques, de cette transition. Nous considérons ensuite les raccourcis claviers comme cas d’étude où nous annotons manuellement une collection de données pour estimer des marqueurs comportementaux comme le début de la transition, sa durée ou la chute de performance. Ceci permet de caractériser finement la transition de trois techniques d’interac- tion. Finalement, nous comparons deux méthodes pour caractériser automatiquement la transition des menus vers les raccourcis.

International audience; To execute a command, a user can make a selection in a menu using pointing actions, or, for example, use shortcuts such as gestures. To go faster, she can learn the positions to point or gestures to perform. In this paper, we present a study comparing learning of positions or directions to select commands. The results obtained reveal similar recall rates, with a slight advantage for positions. The qualitative results suggest an advantage of positions over directions for physical and mental demands. Finally, the study of memorization strategies developed by the subjects provides mnemonic methods that can be useful for designers and users.; Pour exécuter une commande, l’utilisateur peut effectuer une sélection dans un menu à l’aide d’actions de pointage, ou bien, par exemple, utiliser des raccourcis tels que des gestes. Pour aller plus vite, il peut apprendre les positions à pointer ou les gestes à exécuter. Nous présentons dans cet article une étude comparant l’apprentissage de positions et de directions pour sélectionner des commandes. Les résultats obtenus révèlent des taux de rappel sim- ilaires, avec un léger avantage pour les positions. Les résultats qualitatifs suggèrent un avantage des positions sur les gestes en ce qui concerne l’effort physique et cognitif. Finalement, l’étude des stratégies de mémorisation élaborées par les sujets fournit des méthodes mnémoniques pouvant être utiles aux designers et aux utilisateurs.

National audience; This paper introduces a new GUI framework based on the Entity- Component-System model (ECS), where interactive elements (Entities) can acquire any data (Components). Behaviors are managed by continuously running processes (Systems) which select entities by the components they possess. This model facilitates the handling and reuse of behaviors. It allows to define the interaction modalities of an application globally, by formulating them as a set of Systems. We present Polyphony, an experimental toolkit implementing this approach, detail our interpretation of the ECS model in the context of GUIs, and demonstrate its use with a sample application.; Cet article présente un nouveau cadre de conception d’IHM basé sur le modèle Entité-Composant-Système (ECS). Dans ce modèle, les éléments interactifs (Entités) acquièrent librement des données (Composants). Les comportements sont régis par des processus communs s’exécutant continuellement (Systèmes), qui sélection- nent les entités par les composants qu’elles possèdent. Ce modèle favorise la manipulation et la réutilisation des comportements. Il permet de définir globalement les modalités d’interaction d’une application, en les formulant par un ensemble de systèmes. Nous présentons Polyphony, une boîte à outils expérimentale implémen- tant cette approche, détaillons notre interprétation du modèle ECS en contexte IHM, et l’illustrons avec un exemple d’application.

International audience; Decreasing electricity consumption is a major challenge of our society. Eco-feedback methods allow users to get information about their electricity consumption to reduce it. However it is still difficult to determine what are the actions that impact the consumption in practice. In this paper we suggest to apply a What if approach to eco-feedback in a household context. We deploy the Activelec system in personal housings, which allows to apply virtual modifications in appliances usage and to evaluate the savings realized. The results of our experimentation show that participants appreciated the interaction method based on the What if. It allowed them to find and to evaluate efficient modifications in their appliances usage, and several have been applied in practice by the participants. This experimentation shows that the What if paradigm is a potential way for eco-feedback technologies.; Réduire la consommation d’électricité est un enjeu majeur de notre société. Les méthodes eco-feedback permettent aux utilisateurs d’obtenir un retour sur leur consommation d’électricité afin de la diminuer. Toutefois, il est toujours difficile de déterminer concrètement quelles actions impactent la consommation. Dans cet article, nous proposons d’appliquer une méthode What if à l’eco-feedback en contexte domestique. Nous déployons le système Activelec dans des logements personnels, qui permet d’appliquer des changements virtuels dans l’utilisation des appareils et d’évaluer les économies réalisées. Les résultats de notre expérimentation montrent que les participants ont apprécié la méthode d’interaction basée sur le What if. Celle-ci leur a permis de trouver et d’évaluer des modifications efficaces dans l’utilisation de leurs appareils, et certaines ont été appliquées en pratique par les participants. Cette expérimentation montre que le paradigme What if est une piste potentielle pour les technologies eco-feedback.

National audience; Collaborative Virtual Environments (CVEs) are systems that allow multiple participants located remotely to collaborate in a shared virtual space. In order to take advantage of the possibilities offered by such systems, their design must allow users to interact and communicate effectively. One of the open questions in this area concerns the fidelity of the remote partner’s avatar. This can indeed have a direct effect on communication between remote users, more particularly regarding spatial interactions. In this paper, we present a theoretical framework to analyze the fidelity of the remote partner’s avatar in CVE. We also present an ongoing study to compare the effects of two partner’s avatar types on spatial communication. This will permit extracting guidelines for designing CVEs including pointing and spatial guidance tasks.; Les environnements virtuels collaboratifs (EVC) permettent à plusieurs utilisateurs distants de collaborer dans un espace virtuel partagé. Pour tirer parti des possibilités offertes par les EVC, leur conception doit permettre aux utilisateurs d’interagir et de communiquer efficacement. Une des questions ouvertes dans ce domaine concerne la fidélité de l’avatar du partenaire distant. En effet, celle-ci peut avoir une influence directe sur la communication entres utilisateurs distants et plus particulièrement sur leurs interactions spatiales. Dans ce papier, nous présentons un cadre théorique pour analyser la fidélité de l’avatar du partenaire dans un EVC. Nous présentons également une étude expérimentale en cours pour étudier les effets de deux types d’avatars du partenaire sur la communication spatiale dans un EVC. Cette recherche permettra d’extraire des lignes directrices pour la conception des EVC supportant des tâches de pointage et de guidage spatial.

International audience; This paper proposes a new construction of rate-adaptive coding schemes based on Low Density Parity Check (LDPC) codes for Slepian Wolf source coding. Unlike standard rate-adaptive source coding schemes, the code construction we propose is based on finite-length code design tools that permit to greatly improve the decoding performance at short to moderate length. In particular, our method permits to limit the number of short cycles in the codes at all rates of interest, and to avoid eliminating some source bits from the code constraints. The proposed method shows a performance improvement of up to an order of magnitude at almost all the considered rates compared to the standard LDPCA construction.

Les programmes d’enseignement ont fait l’objet d’une réécriture qui a été confiée au Conseil supérieur des programmes. À la suite des consultations effectuées et de l’avis de nombreux linguistes, les programmes publiés en 2015 simplifient la terminologie grammaticale, tout en conservant les distinctions opératoires pour l’orthographe, et introduisent la notion de prédicat. Cet article présente les raisons qui ont présidé aux choix opérés en matière de grammaire et expose les réactions démesurées et déraisonnables qu’a suscitées l’introduction du prédicat dans les programmes scolaires. En effet, à partir de janvier 2017, la presse écrite et audiovisuelle et les réseaux sociaux ont abondamment traité du prédicat. Les critiques ne se fondent ni sur la lecture des programmes, ni sur l’analyse des notions, mais elles s’en prennent au prédicat, accusé d’être responsable d’une détérioration à venir des apprentissages orthographiques et grammaticaux, voire d’être l’instrument de tentatives de dégradation de l’enseignement. The French syllabus for primary and first grade of secondary school has been redefined recently by the Conseil supérieur des programmes. Since this council consulted with many specialists in linguistics, they decided to simplify the grammatical terminology, while maintaining the categories useful as far as spelling is concerned, and introduced the notion of predicate. This paper explains the reasons leading to such decisions and highlights the unreasonable overreactions raised by the introduction of the predicate. Thus, since January 2017, written and audiovisual media and social networking frequently dealt with the predicate. Hardly anybody read the syllabus itself, nor did they analyze the notion of predicate, but critics accused the predicate of being responsible of grammar and spelling’s future decline and even deteriorating education.

International audience; In desktop 3D modeling applications, object manipulation relies on the use of standard transformation widgets. However, these widgets are less efficient on touchscreens due to the low accuracy of touch inputs, and also to the fingertip occlusion issue. In this paper, we propose two unimanual constrained manipulation techniques on TabletPCs. Based on finger identification, our techniques map the index, middle and ring fingers of the dominant hand to the X, Y and Z axes of the coordinate system. After registering the axis-fingers mapping on the screen, users can perform different chording gestures to trigger axis-, plane-constrained or uniform manipulations. We have conducted a user study to examine the learnability and usability of the proposed gestures. The results indicate that these gestures can be memorized quickly after a short training period. Users found some gestures to be easy to use and comfortable while others require additional investigations. These findings permits to give recommendations for designing a unimanual constrained manipulation technique that can be used efficiently in a 3D modeling application on TabletPCs.; Dans les applications de modélisation 3D sur PC, la manipulation avec contraintes d'objets repose sur l’utilisation des widgets de transformation 3D. Cependant, ces widgets sont moins efficaces pour une utilisation sur des écrans tactiles en raison de la faible précision des dispositifs d’entrée et des problèmes d'occultation. Dans ce papier, deux nouvelles techniques uni-manuelles de manipulation 3D sur TabletPC sont proposées. Basées sur l’identification des doigts, nos deux techniques associent l'index, le majeur et l'annulaire de la main dominante aux axes x, y et z du système de coordonnées. Après l’enregistrement de cette association axe-doigts, les utilisateurs peuvent effectuer différents gestes d’accords pour des manipulations avec contraintes sur les axes, sur les plans et des manipulations uniformes. Nous avons mené une étude préliminaire pour examiner l'apprenabilité et l’utilisabilité des gestes proposées. Les résultats indiquent que ces derniers peuvent être mémorisés rapidement. Certains gestes ont été jugés confortables et faciles à utiliser par les utilisateurs alors que d’autres nécessitent davantage d’investigations. Ces résultats permettent de donner des recommandations quant à la conception d’une technique uni-manuelle de manipulation avec contraintes qui peut être utilisée efficacement pour la modélisation 3D sur TabletPC.

International audience; Virtual Reality simulators are increasingly used for training novice surgeons. However, there is currently a lack of guidelines for how to go about achieving the appropriate levels of interaction fidelity for these systems. In this paper, we present two navigation techniques for a needle insertion trainer. The first technique is based on tracking the user’s head position and represents a high-fidelity interaction metaphor. The second technique is touch-based and represents a medium-fidelity interaction metaphor. Our objective is to present the design rational of these techniques, our research questions and a discussion about the experimental study that will be used to compare them.; Les simulateurs virtuels sont de plus en plus utilisés pour former des chirurgiens débutants. Cependant, il y a actuellement un manque de lignes directrices pour définir les niveaux appropriés de fidélité d’interaction pour ces systèmes. Dans ce papier, deux techniques de navigation pour un simulateur virtuel d’insertion d’aiguille sont présentées. La première technique est basée sur le suivi de la position de la tête de l'utilisateur et représente une métaphore d’interaction haute-fidélité. La seconde technique est basée sur l’interaction tactile et représente une métaphore d'interaction moyenne-fidélité. Notre objectif est de présenter la logique de conception de ces techniques, nos questions de recherche et une discussion sur le protocole expérimental qui servira à les comparer.

International audience; In this paper, we explore how to combine the advantages of physical knobs and sliders by using shape-change in order to transform one into another on-demand. By doing so we merge the benefits of both input devices: knobs enable relative angular input with dynamic gain and require little space; sliders require more space but enable absolute linear input and can be grouped to be simultaneously adjusted and monitored. Our initial contextual interviews unveil situations where such dynamic device could be particularly beneficial for professionals such as sound and light engineers as they require tangible devices and high flexibility. We then present the 9 alternative designs of KnobSlider, a shape changing input device that can switch from a knob to slider and vice-versa. We propose a set of 11 requirements for such a shape-changing device and conducted a systematic analysis of our 9 designs against our 11 requirements. This work is a first step toward building a high-fidelity KnobSlider.; Dans cet article, nous examinons comment combiner les avantages des boutons rotatifs et linéaires à l'aide du changement de forme afin de transformer l'un vers l'autre sur demande. Ce faisant, nous fusionnons les avantages des deux dispositifs d’interaction: les boutons rotatifs permettent le contrôle angulaire relatif avec un gain dynamique et nécessitent peu d'espace; les boutons linéaires nécessitent plus d'espace, mais permettent le contrôle linéaire absolu et peuvent être regroupés pour être ajustés et contrôlés simultanément. Nos enquêtes contextuelles initiales dévoilent des situations où un tel dispositif dynamique pourrait être particulièrement bénéfique pour les professionnels tels que les ingénieurs du son et les éclairagistes. Nous présentons ensuite 9 prototypes basse fidélité du KnobSlider, un dispositif de contrôle déformable qui peut changer d'un bouton rotatif à un bouton linéaire et vice-versa. Nous proposons un ensemble de 11 exigences pour un tel dispositif déformable et effectuons une analyse systématique de nos 9 alternatives par rapport à ces 11 exigences. Ce travail est une première étape vers la construction d'un KnobSlider haute fidélité.

International audience; Operating systems support autoscroll to allow users to scroll a window while in dragging mode: the user moves the pointer near the window’s edge to trigger an "automatic" scrolling. Scrolling rate is typically proportional to the distance between the pointer and the window’s edge. This approach suffers from several problems, especially when the window is maximized resulting in a very limited space around the window. An other problem is that for some operations, such as object drag-and-drop, the source and destination might be located in different windows, making it complicated for the computer system to understand user’s intention. In this paper, we present ForceEdge, a novel autoscroll technique relying on trackpads with force-sensing capabilities to alleviate all the problems related to autoscroll. We present the theoretical foundations of ForceEdge and the implementation of a demonstrator that can be used to compare ForceEdge to the other autoscroll methods.; Les systèmes d’exploitation supportent le défilement automatique (autoscroll) dans le but de permettre aux utilisateurs de faire défiler une fenêtre depuis le mode glisser: l’utilisateur déplace le pointeur de la souris vers le bord de la vue, ce qui a pour effet de commencer à faire défiler cette dernière "automatiquement". La vitesse de défilement est généralement associée à la distance entre le pointeur de la souris et le bord de la fenêtre. Cette approche souffre de plusieurs problèmes, notamment que l’espace autour de la fenêtre peut être limité, voire inexistant, par exemple quand une vue est maximisée. Un autre problème est que pour certaines opérations, comme le glisser-déposer d’objets, il est possible que la destination se trouve dans une autre vue que celle d’origine, ce qui crée une situation potentiellement ambiguë pour le système. Dans cet article, nous présentons ForceEdge, une nouvelle technique d’autoscroll qui tire parti des capacités des pavés tactiles récents pour s’affranchir des problèmes inhérents aux méthodes conventionnelles d’autoscroll. Nous présentons les fondements théoriques de ForceEdge et l’implémentation d’un démonstrateur qui permet de comparer ForceEdge aux techniques d’autoscroll par défaut de Mac OS X.

International audience; Ridesharing is often viewed as a way to solve urban transport crisis but fails to become an effective widespread practice in the population. We show in this paper that a behavioral approach allows the consideration of sociological and psychological factors which constitute major challenges to the adoption of this practice. We deduct several hypotheses for promoting massification, finding incentives and enabling trust that we propose to explore with field experiments.; Le covoiturage est souvent cité comme solution à la saturation des transports urbains mais reste une pratique marginale dans la population. Nous montrons dans ce papier qu’une approche comportementale permet la prise en compte de facteurs sociologiques et psychologiques qui constituent des freins majeurs à l’adoption de cette pratique. Nous en déduisons plusieurs hypothèses sur le passage à l’échelle, les incitations et la confiance que nous proposons d’explorer par des expérimentations de terrains.

International audience; Résumé :Cette recherche propose la lecture d’œuvres de science-fiction avec l’assistance de méthodes mathématiques issues de la théorie des graphes. Notre approche associe lecture serrée et lecture distante pour représenter les liaisons entre les personnages, à partir de la structure formée par leurs co-occurrences dans le texte. Ce travail comporte trois propositions principales. La première est l’introduction d’une méthode de « lecture intermédiaire » (ou « middle reading ») alliant lecture serrée et lecture distante pour fournir une analyse du système des personnages d’une œuvre de fiction. Elle recourt à la visualisation de réseaux et à l’exploitation de leurs propriétés mathématiques (centralités, formations de communautés). La deuxième proposition est une typologie d’œuvres basée sur la structure formée par leurs personnages. La dernière proposition est un essai de lecture des œuvres basée sur la qualification des personnages, à fin d’étude des représentations.Summary : This paper introduces a way of studying science fiction works using mathematical methods grounded in graph theory. Our approach combines close and distant reading in order to describe the structural roles of characters, as they appear in the network built from their co-occurrences in the text. This study includes three main results. The first consists in the introduction of « middle reading », a method combining close and distant reading to analyze character systems in works of fiction. It relies on network visualization together with mathematical concepts like centrality or cluster detection. The second result consists in a typology of the works composing the corpus, based on the structure of their character networks. The third result is a reading proposal based on character qualification as scientist, technician or politician. This approach adds a dimension to these characters networks, thus allowing a richer interpretation of characters systems.

Traduction française de l'article "Self-­‐Archiving with Ease in an Institutional Repository: Microinteractions and the User Experience" publié dans la revue Information Technology and libraries, septembre 2015; Details matter, especially when they can influence whether users engage with a new digital initiative that relies heavily on their support. During the recent development of MacEwan University’s institutional repository, the librarians leading the project wantedto ensure the site would offer users an easy and effective way to deposit their works, inturn helping to ensure the repository’s long-­‐term viability. The following paper discusses their approach to user-­‐testing, applying Dan Saffer’s framework of Microinteractions to how faculty members experienced the repository’s self-­‐archiving functionality. It outlines the steps taken to test and refine the self-­‐archiving process,shedding light on how others may apply the concept of microinteractions to better understand a website’s utility and the overall user experience that it delivers.; Chaque détail compte, particulièrement quand il peut influencer l'investissement des usagers envers une nouvelle initiative numérique qui se base beaucoup sur leur soutien. L'Université MacEwan (Edmonton, Canada) a récemment lancé son archive institutionnelle (Ro@M), les bibliothécaires qui menaient le projet ont souhaité s'assurer que le site offrait un moyen facile et efficace de déposer des documents et ainsi assurer la viabilité de l'application sur le long terme. Cet article présente leur approche des tests d'utilisabilité en mettant en pratique le cadre des microinteractions de Dan Saffer. Il souligne les étapes suivies pour les tests et précise la procédure d'auto-archivage, mettant en lumière comment d'autres peuvent appliquer le concept de microinteractions pour mieux comprendre l'utilité et l'expérience utilisateur prodiguées par un site web.

International audience; This paper proposes a method to understand saturation in the railways. It will be applied to the case of Lyon‐Paris High‐Speed Line. The method presented enables to test and compare different solutions to cope with saturation. It can be considered as both a tool for decision‐makers and a support to investment choices.; Ce papier propose une méthode pour conceptualiser la saturation d’une infrastructure ferroviaire. Elle est appliquée au cas de la Ligne à Grande Vitesse Paris‐Lyon et permet de tester et comparer plusieurs pistes de désaturation. Cette méthode peut être considérée comme un outil de décision au service des politiques publiques pour guider le choix en investissements.

International audience; In this paper, we explore the potential of mobile devices for the control and the composition of sound spatialization. We conducted interviews with four composers to understand their needs and guide the design of a new mobile application that allows the drawing of sound sources trajectories. We describe three collaborations with composers who appropriated the application to create trajectories and integrate them into their creations.; Dans cet article, nous explorons les possibilités offertes par les dispositifs mobiles pour le contrôle et l'écriture de la spatialisation sonore. Nous avons réalisé des entre-tiens avec quatre compositeurs pour comprendre leurs besoins et guider la conception d'une nouvelle application mobile permettant le dessin de trajectoires de sources sonores. Nous décrivons des collaborations avec trois compositeurs qui se sont appropriés l'application pour créer des trajectoires et les intégrer dans leurs créations.

International audience; The development of high-speed trains has been an important tool for national and regional planning in France for 30 years. Different levels of public policies (State, regional and local authorities) have funded a network linking a part of French metropolitan system. Analysis of planning documents can demonstrate a French political consensus on the importance of the High Speed Rail. But a change in the consensus seems to be emerging. The inability to finance all new railway projects and the need to finance the renovation of the existing network, require a new infrastructure approach. This approach is based on the construction of a technical model, la Ligne nouvelle, currently being negotiated between the actors of public policies and the manager of the national infrastructure. The purpose of this paper is to analyze this passage from the TGV to the Ligne nouvelle. This analysis is applied to a particular example, la Ligne nouvelle Paris Normandie, to illustrate this transition imagined to anticipate the evolution of high-speed rail networks in France.; Le développement des Lignes ferroviaires à grande vitesse (LGV) en France a constitué un outil majeur des politiques d’aménagement du territoire ces trente dernières années. Il traduit une lecture spécifique du rapport vitesse/territoire partagée par l’État, ses acteurs ferroviaires (SNCF, RFF) et les collectivités territoriales. Sans minorer la conflictualité induite par ces grands projets et leurs tracés, il reste qu’une vision partagée de la nécessité de cette grande vitesse ferroviaire a autorisé ce développement et les financements nécessaires. Un changement de période récent est pourtant à signaler. Ce changement est lié à deux facteurs, la difficulté de financement dans un contexte de contraction des ressources dédiées aux infrastructures nouvelles et la prise de conscience récente de la dégradation du réseau existant. Cette période voit alors émerger une remise en cause du tout TGV et une réflexion nouvelle sur la vitesse ferroviaire. Cette remise en cause, encore partielle, implique néanmoins un travail d’évolution du référentiel d’évaluation de l’infrastructure ferroviaire et une négociation entre le gestionnaire d’infrastructure et les collectivités territoriales. L’objectif de notre article, développé autour de l’exemple de la Ligne nouvelle Paris‐Normandie et du débat public associé, est d’apprécier cette mobilisation du critère de la vitesse dans les exercices de planification et de prospectives territoriales.

International audience; With the emergence of reconfigurable FPGA circuits as a credible alternative to GPUs for HPC acceleration, new compilation paradigms are required to map high-level algorithmic descriptions to a circuit configuration (High-Level Synthesis, HLS). In particular, novel parallelization algorithms and intermediate representations are required. In this paper, we present the data-aware process networks (DPN), a dataflow intermediate representation suitable for HLS in the context of high-performance computing. DPN combines the benefits of a low-level dataflow representation-close to the final circuit-and affine iteration space tiling to explore the parallelization trade-offs (local memory size, communication volume, parallelization degree). We outline our compilation algorithms to map a C program to a DPN (front-end), then to map a DPN to an FPGA configuration (back-end). Finally, we present synthesis results on compute-intensive kernels from the Polybench suite.

International audience; Geographical imagination is deeply rooted in the relations our societies sustain with space. The significance of imagination and mythological constructions of territories is commonly identified as part of our representations and practices. The role of imagination, and its unrealistic function, in the meaning of places is well known, even more in the case of urban peripheries yet identified as problematic. Since decades, suburban mythology, relying classically on the figure of “city to countryside” and the attractiveness of property, has made the production of these new territories possible. But, when the analysis of this myth until now has nearly exclusively concentrated on dwelling places, we propose to reveal a blind spot of imaginations: mobility in suburban areas, especially when considering the sustainability injunction. Based on a qualitative survey carried out in suburban area of a medium size town (Tours, France), this paper renders the role of imaginations towards mobility in the today life of inhabitants. We show how mobility mythology, as well as dwelling myth, influences suburban way of life. Moreover, we insist on the capability of these imaginations to offer spaces of conciliation encouraging more sustainable way of life.; L’imaginaire géographique est au coeur des rapports que les sociétés entretiennent avec leurs territoires. Ainsi, on connaît l’importance du fruit de l’imagination, la construction mythologique, et son influence sur les représentations et les pratiques de l’espace. On sait notamment le rôle de l’imaginaire qui confère à l’espace sa signification, dans l’extension – aujourd’hui jugée problématique – des périphéries urbaines. Les « mythologies pavillonnaires », la ville à la campagne, le « tous propriétaires », ont énormément oeuvré, et ce depuis plusieurs décennies, pour rendre possible le développement de ces nouveaux territoires. Cependant, quand jusqu’à présent l’analyse des imaginaires spatiaux s’est principalement attachée aux espaces de résidence, il demeure selon nous un point aveugle, celui des imaginaires de la mobilité dans les périphéries urbaines – notamment lorsqu’ils sont confrontés aux injonctions sociétales à la durabilité. Partant d’une enquête réalisée auprès d’une trentaine d’habitants des espaces périurbains d’une ville moyenne (Tours), nous proposons d’explorer la place de l’imaginaire lié à la mobilité dans les discours des habitants du périurbain. Nous montrons ainsi, à côté de la mythologie résidentielle, la place qu’occupe l’imaginaire de la mobilité et comment celui-ci ménage des espaces de conciliation compatibles avec les enjeux de durabilité.

National audience; In this paper, we propose SuperVision, a novel interaction technique for controlling distant connect objects in smart-home. Users point an object with their remote control to visualize its state, and select its functionalities. To achieve this goal, 1) we present a novel remote control augmented with a video-projector and a slider; 2) we introduce a visualization allowing users to see through the walls in order to control objects in the line of sight as well as objects in another rooms; 3) we describe applications relying on this interaction technique; Dans ce papier, nous proposons SuperVision, une nouvelle technique d’interaction pour contrôler à distance les "objets connectés" d'une maison intelligente. Les utilisateurs pointent en direction d’un objet à l’aide d’une télécommande pour visualiser son état et sélectionner ses fonctionnalités. Pour ce faire : 1) nous présentons une nouvelle télécommande qui est augmentée d’un pico-projecteur et d’une glissière ; 2) nous introduisons une visualisation permettant à l’utilisateur de "voir" à travers les murs afin de pouvoir contrôler de la même manière les objets visibles et ceux qui ne sont pas dans son champ de vision ; 3) nous décrivons des applications reposant sur cette technique d’interaction.

Urban governments tend to pedestrianise the centres of cities or to implement street designs which reduce the amount of cars in the public spaces of these centres: pedestrian areas, reduction of on-street parking, implementation of 'zones de rencontre' (living streets), etc. Prima facie, these policies, which encourage pedestrian mobility to the detriment of automotive mobility, seem to be obviously favourable to the preservation of environment. In France, pedestrianisation is presented by the national authorities as one of the tools contributing to the sustainable development of urban territories. Another hypothesis, however, is that these policies are part of urban marketing strategies of cities engaged in inter-urban competition processes - which lead to increase the value and attractiveness of strategic places in the city and tend to displace problems (and deprived populations) to other parts of the urban territory. Thus, as a whole, these policies would not really contribute to sustainable development. Referring to theoretical frameworks related to the entrepreneurial mutation of urban policies, this paper presents an overview of research and empirical results dealing with the implementation and effects of pedestrianisation or other policies in favour of pedestrians in city centres. As a whole, this material gives some credit to the latter hypothesis.; Les gouvernements urbains tendent à piétoniser les centres-villes ou à mettre en oeoeuvre des conceptions de voirie réduisant la quantité d'automobiles dans les espaces publics de ces quartiers centraux : aires piétonnes, réduction du stationnement sur la voirie, aménagement de « zones de rencontre », etc. À première vue, ces politiques, qui assurent la promotion des déplacements à pied au détriment des déplacements motorisés, semblent à l'évidence être favorables à la préservation de l'environnement. La piétonisation est d'ailleurs présentée par l'État comme l'un des instruments contribuant au développement durable des territoires urbains. Cependant, une autre hypothèse est qu'elles participent de stratégies de marketing urbain de villes engagées dans des processus de compétition inter-territoriale - qui conduisent à accroître la valeur et l'attractivité de lieux stratégiques de la ville et tendent à déplacer les problèmes (et les populations défavorisées) vers les autres parties du territoire urbain. Ainsi, globalement, ces politiques n'apporteraient pas de réelle contribution au développement durable. Se référant à des cadres théoriques relatifs à la mutation entrepreneuriale des politiques urbaines, cet article présente un aperçu de recherches et résultats empiriques traitant de la mise en oeoeuvre et des effets d'opérations de piétonisation ou d'autres politiques en faveur des piétons dans les centres-villes. Dans leur ensemble, les éléments rassemblés accréditent plutôt la seconde hypothèse.

International audience; A special session on High-Speed Rail (HSR) and regional and urban growth was organised at the 49th French-speaking Regional Science Association (ASRDLF) Annual Conference (Belfort, 9-11 July 2012). It consisted of two sub-topics. The first was an historical approach of the interactions between transport facilities and territorial dynamics. The second was focused on the cross-relationships between HSR, tourism and territory. This special issue of RTS is a selection of papers presented during this special session.; Le XLIXe colloque de l’ASRDLF, qui s’est déroulé à Belfort du 9 au 11 juillet 2012, a donné lieu à une session spéciale sur le thème « Grande vitesse ferroviaire et développement régional et urbain » avec deux axes consacrés respectivement à la mise en perspective historique des interactions entre infrastructures de transport et dynamiques territoriales et à la question des liens croisés entre TGV, tourismes et territoires. C’est à partir d’une sélection des communications qui ont été présentées que ce numéro spécial est construit.

International audience; Evolution in the context of use requires evolutions in the user interfaces even when they are currently used by operators. User Centered Development promotes reactive answers to this kind of evolutions either by software evolutions through iterative development approaches or at runtime by providing additional information to the operators such as contextual help for instance. This paper proposes a model-based approach to support proactive management of context of use evolutions. By proactive management we mean mechanisms in place to plan and implement evolutions and adaptations of the entire user interface (including behaviour) in a generic way. The approach proposed handles both concentration and distribution of user interfaces requiring both fusion of information into a single UI or fission of information into several ones. This generic model-based approach is exemplified on a safety critical system from space domain. It presents how the new user interfaces can be generated at runtime to provide a new user interface gathering in a single place all the information required to perform the task. These user interfaces have to be generated at runtime as new procedures (i.e. sequences of operations to be executed in a semi-autonomous way) can be defined by operators at any time in order to react to adverse events and to keep the space system in operation. Such contextual, activity-related user interfaces complement the original user interfaces designed for operating the command and control system. The resulting user interface thus corresponds to a distribution of user interfaces in a focus+context way improving usability by increasing both efficiency and effectiveness.

International audience; In this paper we propose a new methodology of development dedicated to cooperative ADAS. This methodology led us to implement a new framework for prototyping a communicating ADAS system. Within this framework, we combine the data from multiple modules: a vision module, a V2V communication module and Geo‐localization GPS module, in order to accomplish a cooperative warning system. To achieve this goal, we have developed a prototyping system based on the principle of augmented reality, in which we replay real data and change the characteristics of the communication system. The GPS data and routing protocols were crucial elements for V2V communication simulation made with ns‐2 simulator. We conducted different scenarios on real experimental platform consists of LaRA vehicles. Multiple results are presented to show up the compatibility and the performance efficiency of real‐time multi sensors in an integrated framework for collision avoidance applications. The implementation of the warning system was used to estimate the number of pre‐collisions detected in both real and simulated situations. The difference between these two situations was analyzed for several scenarios corresponding to different road situations. The results showed that the simulation of V2V communication provide additional data that improve the implementation of these new ADAS and to assess their performance.; Cet article propose une nouvelle méthodologie de développement dédiée aux systèmes ADAS coopératifs. Cette méthodologie nous a conduit à mettre en œuvre un nouveau cadre de prototypage des systèmes ADAS communicants. Dans ce cadre, nous combinons les données de plusieurs modules, un module de vision, un module de communication V2V et un module de géolocalisation GPS, pour réaliser un système d’alerte coopératif. Afin d’atteindre cet objectif, nous avons développé un système de prototypage basé sur le principe de la réalité augmentée, dans lequel nous pouvons rejouer des données réelles et modifier les caractéristiques du système de communication. Les données du système de géolocalisation GPS et les protocoles de routage ont été des éléments primordiaux pour la simulation de la communication V2V réalisée avec le simulateur ns‐2. Nous avons effectué différents scénarios réels sur la plate‐forme du prototype LaRA composée de véhicules instrumentés. Plusieurs résultats sont présentés pour illustrer la compatibilité et l’efficacité de l’intégration des données réelles issues de plusieurs capteurs dans ce nouveau système de prototypage pour les applications d’alerte. La mise en œuvre du système d’alerte a permis d’estimer le nombre de pré‐collisions détectées dans deux situations, une réelle et une simulée. L’écart entre ces deux configurations a été étudié et analysé pour plusieurs scénarios qui correspondent aux différentes situations routières. Les résultats ont montré que les simulations de communications V2V fournissent des données complémentaires qui améliorent la mise en œuvre de ces nouveaux ADAS et permettent d’évaluer leurs performances.

International audience; What are the interindividual relationships involved in periurban journeys and what is their outcome? Do they create a sense of collective solidarity? Do they concern particular types of journey? These are the issues raised in this paper. Based on a qualitative analysis of space and time in relation to journeys taken by inhabitants using public transport or car‐sharing within the Grenoble district (France), we show that journeys between home and work play a dual role of buffer and link between the spheres of daily life, because they cover a range of uses and social interactions. The notion of sharing not only a passenger compartment and standards and rules of interaction but also a sense of collective solidarity, rooted as much in everyday space (home, workplace) as in the experience of the journey itself, leads us to define an identity of movement. This includes a feeling of recognition and belonging based on sharing the same material conditions and ideals of transport, central to the understanding of the individual and collective organization of journeys.; Quelles sont les relations interindividuelles en jeu dans la mobilité périurbaine et que produisent‐elles ? Fabriquent‐elles des solidarités collectives ? Définissent‐elles des modalités de déplacements particulières ? Tel est le questionnement et l’objet de cette contribution. Partant d’une analyse qualitative des espaces‐temps de la mobilité dans le moyen‐Grésivaudan (Grenoble, France), auprès d’habitants recourant aux transports en commun ou au covoiturage, nous montrons que les trajets domicile‐travail jouent un double rôle de sas et de lien entre les sphères du quotidien parce qu’ils sont investis d’une diversité d’usages et d’interactions sociales. Le partage d’un même habitacle, de normes et de règles d’interactions mais aussi de solidarités collectives ancrées tout autant dans les territorialités habituelles (résidence, travail) que dans l’expérience de mobilité nous amène à définir une identité de mouvement. Cette dernière qualifie un sentiment de reconnaissance et d’appartenance fondé sur le partage des mêmes conditions matérielles et idéelles de déplacement, au cœur de la compréhension de l’organisation individuelle et collective des mobilités.

The probability hypothesis density (PHD) methodology is widely used by the research community for the purposes of multiple object tracking. This problem consists in the recursive state estimation of several targets by using the information coming from an observation process. The purpose of this paper is to investigate the potential of the PHD filters for real-time traffic state estimation. This investigation is based on a Cell Transmission Model (CTM) coupled with the PHD filter. It brings a novel tool to the state estimation problem and allows to estimate the densities in traffic networks in the presence of measurement origin uncertainty, detection uncertainty and noises. In this work, we compare the PHD filter performance with a particle filter (PF), both taking into account the measurement origin uncertainty and show that they can provide high accuracy in a traffic setting and real-time computational costs. The PHD filtering framework opens new research avenues and has the abilities to solve challenging problems of vehicular networks.

International audience; This paper describes the first step of a research project with the aim of predicting students' performance during an online curriculum on a LMS and keeping them from falling behind. Our research project aims to use data mining, machine learning and artificial intelligence methods for monitoring students in e-learning trainings. This project takes the shape of a partnership between computer science / artificial intelligence researchers and an IT firm specialized in e-learning software. We wish to create a system that will gather and process all data related to a particular e-learning course. To make monitoring easier, we will provide reliable statistics, behaviour groups and predicted results as a basis for an intelligent virtual tutor using the mentioned methods. This system will be described in this article. In this step of the project, we are clustering students by mining Moodle log data. A first objective is to define relevant clustering features. We will describe and evaluate our proposal. A second objective is to determine if our students show different learning behaviours. We will experiment whether there is an overall ideal number of clusters and whether the clusters show mostly qualitative or quantitative differences. Experiments in clustering were carried out using real data obtained from various courses dispensed by a partner institute using a Moodle platform. We have compared several classic clustering algorithms on several group of students using our defined features and analysed the meaning of the clusters they produced.

In this paper, we demonstrate how textual analysis and network analysis are complementary in displaying various groups from a bibliographic data bank, then in building the corresponding networks of co-publication. The Alceste software and Pajek, used on the same ‘‘set’’ of data including 5,000 references, allowed us to objectify the existence of various epistemic communities, as well as the links within and between communities related to the issue of ‘‘measurement’’ in education.

International audience; In order to address the large variety of channel coding options specified in existing and future digital communication standards, there is an increasing need for flexible solutions. Recently proposed flexible solutions in this context generally presents a significant area overhead and/or throughput reduction compared to dedicated implementations. This is particularly true while adopting an instruction-set programmable processors, including the recent trend toward the use of Application Specific Instruction-set Processors (ASIP). In this paper we illustrate how the application of adequate algorithmic and architecture level optimization techniques on an ASIP for turbo decoding can make it even an attractive and efficient solution in terms of area and throughput. The proposed architecture integrates two ASIP components supporting binary/duo-binary turbo codes and combines several optimization techniques regarding pipeline structure, trellis compression (Radix4), and memory organization. The logic synthesis results yield an overall area of 1.5mm 2 using 90nm CMOS technology. Payload throughputs of up to 115.5Mbps in both double binary Turbo codes (DBTC) and single binary (SBTC) are achievable at 520MHz. The demonstrated results constitute a promising trade-off solution between throughput and occupied area comparing with existing implementations.

cote interne IRCAM: Hug11a; None / None; National audience; Sound design for interactive products is rapidly evolving to become a relevant topic in industry. Scientific research from the domains of Auditory Display (AD) and Sonic Interaction Design (SID) can play a central role in this development, but in order to make its way to market oriented applications, several issues still need to be addressed. Building on the sound design process employed at the Sound Perception and Design (SPD) group at IRCAM, and the information gathered from interviews with professional sound designers, this paper focuses on revealing typical issues encountered in the design process of both science and design oriented communities, in particular the development of a valid and revisable, yet innovative, design hypothesis. A second emphasis lies on improving the communication between sound and interaction designers. In order to address these challenges, a conceptual framework, which has been developed using both scientific and designerly methods, was presented and evaluated with expert reviews.

This paper deals with the presentation of different multi-user detectors in the Universal Mobile Telecommunications System (UMTS) context. The challenge is always to optimize the compromise between performance and complexity. Compared with the solution commonly used today, the rake detector, successive interference cancellation (SIC) detector has better performance despite its higher complexity. Our innovative solution proposes joining detector and channel turbo decoder to get a significant gain in terms of performance. Furthermore, when detection and decoding are implemented in a single function, complexity does not increase much.

149-152; International audience; Current window managers are based on the use of overlapping windows, which implies the notion of a window's depth. In order to facilitate the management of windows in desktop environments, recent work has explored their grouping into layers of non-overlapping windows. In this note, we investigate the effect of three visual depth cues on the perception of the depth of such layers: luminosity, blurring and shadow. The paper reports on a controlled experiment that indicates that luminosity helps users to assess the number of layers while blurring and shadow have no effect.

Sound sample indexing usually deals with the recognition of the source/cause that has produced the sound. For abstract sounds, sound effects, unnatural, or synthetic sounds, this cause is usually unknown or unrecognizable. An efficient description of these sounds has been proposed by Schaeffer under the name morphological description. Part of this description consists in describing a sound by identifying the temporal evolution of its acoustic properties to a set of profiles. In this paper, we consider three morphological descriptions: dynamic profiles (ascending, descending, ascending/descending, stable, impulsive), melodic profiles (up, down, stable, up/down, down/up) and complex-iterative sound description (non-iterative, iterative, grain, repetition). We study the automatic indexing of a sound into these profiles. Because this automatic indexing is difficult using standard audio features, we propose new audio features to perform this task. The dynamic profiles are estimated by modeling the loudness over-time of a sound by a second-order B-spline model and derive features from this model. The melodic profiles are estimated by tracking over time the perceptual filter which has the maximum excitation. A function is derived from this track which is then modeled using a second-order B-spline model. The features are again derived from the B-spline model. The description of complex-iterative sounds is obtained by estimating the amount of repetition and the period of the repetition. These are obtained by computing an audio similarity function derived from an Mel frequency cepstral coefficients (MFCC) similarity matrix. The proposed audio features are then tested for automatic classification. We consider three classification tasks corresponding to the three profiles. In each case, the results are compared with the ones obtained using standard audio features.