Building Space Time Block Codes with set partitioning for three transmit antennas: application to STTC Codes

Publication in the conference proceedings of EUSIPCO, Florence, Italy, 200

Les technologies de l'habitat, de l'information et de la communication au service des personnes vieillissantes : approche sémiotique et éthique des usages

International audienceA l'initiative de décideurs institutionnels ou au sein de services hospitaliers spécialisés, des solutions technologiques ont été déployées souvent sur la base d'enquêtes préliminaires associant les pathologies des personnes à des solutions technologiques pensées comme étant une réponse adéquate par les décideurs médico-sociaux. En particulier le déploiement de divers "packs" domotiques et TIC, ont été menées à l'initiative de collectivités territoriales ces 3-4 dernières années. Nous citerons la Corrèze et la Creuse pour la Région Limousin. Appropriation, socialisation, plaisir de l'utilisation de l'objet sont donc des concepts à intégrer dans la démarche de conception des objets TIC destinés aux personnes en perte d'autonomie. Ces concepts relèvent d'études sémiotiques. Cette démarche s'intéresse à la manière dont l'usager, avec ses compétences actuelles et les expériences gestuelles, culturelles qu'il a développées au fil des pratiques de la vie quotidienne perçoit tel ou tel objet numérique destiné à l'aider. En l'occurrence, il s'agit d'interroger pour un usager donné, en amont, pendant et en aval de la conception, la pertinence de la forme, de la taille, de la couleur d'une interface numérique. Mais il s'agit aussi d'analyser l'efficience du mode d'interaction gestuelle que propose le dispositif. Comment transformer l'interaction avec un objet en véritable coopération fondée sur un mode sensible et intelligible singulier, perçu positivement par l'usager ? C'est à cette question que nous répondons

On the semiotic appropriation of ICT tools for people in loss of autonomy

International audienceIt is now widely accepted that ICT objects for people with loss of autonomy do not meet the expected services. Their non-appropriation by the people is the main reason. This finding is important for policy makers and institutional medical organizations and caregivers as well as device manufacturers. Consequently, the concept of adequate appropriation is a process that must be developed in order to reduce dependency and introduce the notion of "natural health behavior." The object / equipment / device must be integrated into the gesture and everyday history of the person. It is the goal of a semiotic approach should also allow through better use and greater ownership, a better assessment of the impact of the object on the welfare and better living of the person

Semiotics and semantic: tools for an effective appropriation of information, communication and health technologies

International audienceAbstract: As Cultural Objects, ICTs belong to the human sphere. This surround is driven by polysemiotics performances (involving many signs systems) which praxeological semantics permits to interpret. The term of Praxeology (or theory of human action) is used so far as it concerns to link principally technical objects to social practices in which they appears. The meaning of these objects is then studied in relation with the actions to which they are associated. In the case of the ICTs, their proposed "coupling" approaches (in particular for the HMIs) lead to a better use and simplify the appropriation process. The study of users' discourses is very interesting from this point of view, and should lead to formulate recommendations for a more efficient appropriation of the ICTs. In parallel, according to a new idea of design related to electronic objects semiotics often takes place in a plan that relates different disciplines. It offers a common language to all partners and gives tools for a clear depiction of the objects and subjects involved in the interaction and tell how they interact. Example of vocal interfaces is described

Tatouage d'images cryptées pour l'aide au télédiagnostic

Le développement d'interfaces de visualisation à distance pour des images médicales rencontre des problèmes de sécurité de données. Dans ce papier, nous présentons une combinaison des techniques de cryptage et de tatouage d'images. Nous proposons un système permettant de transférer des images médicales de manière sécurisée en générant une clef pour crypter l'image, puis en tatouant l'image avec la clef de cryptage et les données concernant le patient

GT2004-53372 FORCED RESPONSE PREDICTION METHODOLOGY FOR THE DESIGN OF HP COMPRESSORS BLADED DISKS

ABSTRACT This paper presents a general approach related to bladed disk forced response prediction and a typical way to use it in the design process. Firstly, a good confidence level in prediction tools must be reached. The first application is a highly instrumented HP compressor blisk representative of a real engine environment. Simulation of forced response is compared to measurements in order to check the accuracy of prediction. For this test case, the results obtained are in very good agreement with measurements. The good quality of prediction is due to the complete characterization performed on the test case: all the influent parameters were identified before testing. But during the design process, many important parameters are unknown and this level of accuracy can not be obtained. Nevertheless, forced response prediction in the early design process can provide interesting information even if uncertainties are high for some parameters. As an illustration, a second application is proposed, based on the design experience of a new HP compressor of a known engine family. Some forced response predictions were performed during development and compared afterwards with measurements obtained during engine testing. This analysis has permitted to confirm some technical choices and to assess the High Cycle Fatigue risk associated to this new engine configuration. INTRODUCTION The forced response prediction of bladed disks is the main challenge to mitigate the risk of vibration of these structures. It is a way to avoid the late discovery of High Cycle Fatigue problems. Indeed, in the current design process, engine manufacturers know the vibration levels only at the very end of the development, during engine testing, or sometimes in operation (it is difficult to cover the entire flight domain with ground testing). But forced response prediction is complex because much of the needed information is unknown at the early stages of the design process: -an accurate computation of the aerodynamic forcing function -the dynamic behavior of the structure that can be complex (high modes, mistuning, non linearity) -an estimation of the total damping, as a combination of mechanical and aeroelastic damping. Many solutions have been proposed concerning the forced response simulation tools, both for unsteady aerodynamics and for the fluid/structure coupling. This paper does not describe a new computational method but tries to address the problem of the way to use forced response prediction in the design process. This paper 's objective is to propose a general methodology coherent with an industrial context, that is to say with many unknown parameters

The EPOC project: Energy Proportional and Opportunistic Computing system

15397International audienceWith the emergence of the Future Internet and the dawning of new IT models such as cloud computing, the usage of data centers (DC), and consequently their power consumption, increase dramatically. Besides the ecological impact, the energy consumption is a predominant criteria for DC providers since it determines the daily cost of their infrastructure. As a consequence, power management becomes one of the main challenges for DC infrastructures and more generally for large-scale distributed systems. In this paper, we present the EPOC project which focuses on optimizing the energy consumption of mono-site DCs connected to the regular electrical grid and to renewable energy sources

Impairment of gut microbial biotin metabolism and host biotin status in severe obesity: effect of biotin and prebiotic supplementation on improved metabolism

Objectives Gut microbiota is a key component in obesity and type 2 diabetes, yet mechanisms and metabolites central to this interaction remain unclear. We examined the human gut microbiome\u27s functional composition in healthy metabolic state and the most severe states of obesity and type 2 diabetes within the MetaCardis cohort. We focused on the role of B vitamins and B7/B8 biotin for regulation of host metabolic state, as these vitamins influence both microbial function and host metabolism and inflammation. Design We performed metagenomic analyses in 1545 subjects from the MetaCardis cohorts and different murine experiments, including germ-free and antibiotic treated animals, faecal microbiota transfer, bariatric surgery and supplementation with biotin and prebiotics in mice. Results Severe obesity is associated with an absolute deficiency in bacterial biotin producers and transporters, whose abundances correlate with host metabolic and inflammatory phenotypes. We found suboptimal circulating biotin levels in severe obesity and altered expression of biotin-associated genes in human adipose tissue. In mice, the absence or depletion of gut microbiota by antibiotics confirmed the microbial contribution to host biotin levels. Bariatric surgery, which improves metabolism and inflammation, associates with increased bacterial biotin producers and improved host systemic biotin in humans and mice. Finally, supplementing high-fat diet-fed mice with fructo-oligosaccharides and biotin improves not only the microbiome diversity, but also the potential of bacterial production of biotin and B vitamins, while limiting weight gain and glycaemic deterioration. Conclusion Strategies combining biotin and prebiotic supplementation could help prevent the deterioration of metabolic states in severe obesity