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Observer-based relay feedback controller design for LTI systems
No full textInternational audienceThis paper presents a design approach for observer-based relay feedback controllers. A switching law dependent on the estimation state is designed while usinga Luenberger observer. The stabilization problem leads to qualitative conditions. A numerical example is provided to assess the effectiveness of the developed method
Operators for Template-Based MDE
No full textInternational audienceIn MDE, design of systems can be improved and accelerated thanks to reusable models which are made available in model repositories or libraries. This paper focuses on the construction and exploitation of “off-the-shelf” model template bases. Model templates are parameterized models which are adaptable to various application contexts. Due to their parameterization, model templates have their own modeling space. In this paper, we present the main modeling ac- tivities that underlie this space, their dedicated engineering processes and their actors, and we contribute to the model reuse improvement by detailing new tem- plate operators for the described modeling activities. A software environment is shown to illustrate template based engineering in Eclipse
Fast head turns detection in low quality videos using optical flow
No full textNational audienceDetecting automatically a person who needs help in a shopping center represents an unique challenge in computer vision. It lies in the poor quality of images we consider. Our method focuses on consistency of dense optical flow to extract head turns.Détecter automatiquement une personne qui a besoin d'aide dans un magasin représente un défi en vision par or-dinateur. Cela réside dans le fait que la qualité des images est mauvaise. Notre méthode se porte sur un calcul de co-hérence des flots optiques dense
Towards Model-Driven Multi-Cloud Resource Management
No full textMulti-Cloud computing has established itself as a paradigm of choice for acquiring resources from different providers and get the best of each of them to run their applications. However, managing resources in Multi-Cloud remains a challenging task. Several multi-cloud libraries based approaches include Apache Libcloud, Apache jclouds, δ-cloud, Daseincloud, fog, and pkgcloud exist in the cloud market. But these are still low level as Multi-Cloud management tasks must always be programmed. Therefore, application platforms are need to help developers to succeed. In this paper we give a model-driven approach for managing resources of multiple clouds at high level. We illustrate our proposal by providing a prototype of Multi-Cloud Designer for managing resource from multiple clouds
Gestion de ressources multi-nuages dirigé par des modèles
No full textNational audienceL'informatique multi-nuages s'est imposée comme un paradigme de choix pour acquérir des ressources provenant de différents fournisseurs de nuage et obtenir le meilleur de ces derniers pour exécuter des applications. L'informatique multi-nuages consiste en l'utilisation de multiples environnements de nuages indépendants qui ne nécessitent pas d'accord préalable entre les fournisseurs de nuage ou un tiers. Cependant la gestion des ressources dans un environne-ments multi-nuages reste une tâche difficile. Plusieurs bibliothèques multi-nuages comprenant Apache Libcloud, Apache jclouds, δ-cloud, Daseincloud, fog et pkgcloud existent sur le marché de nuage. Mais la gestion des ressources multi-nuages par ces bibliothèques se fait toujours en programmant dans un langage spécifique et reste de bas niveau. Par conséquent, nous avons besoin d'une solution permettant aux développeurs de gérer de manière simple les ressources multi-nuages. Dans cet article nous fournissons une approche dirigée par les modèles pour gérer à un niveau d'abstraction plus haut les ressources provenant de plusieurs nuages. Nous illustrons notre proposition en fournissant un prototype du Designer multi-nuages pour gérer des ressources provenant de plusieurs nuages
Offshoring and labour market reforms in Germany: Assessment and policy implications
No full textInternational audienceStarting from the diagnosis that Germany has had better economic outcomes than most advanced countries since the mid-2000s, we propose a general equilibrium model to answer the following two questions: Why is it so and is the German experience applicable to other EU countries? Whereas a large number of observers explain German competitiveness by the labour market reforms implemented from 2003 to 2005 (Hartz laws), we suggest that (i) the gains in competitiveness are essentially due to offshoring and (ii) the labour market reforms have subsequently reduced the offshoring-related unemployment by decreasing the reservation wage, creating thereby low skilled jobs in non-tradable services. These reforms have also reinforced inequality already generated by offshoring. In contrast with the traditional explanation based on the Hartz reforms, our model findings and simulations fit well with the sequence of observed facts. This experience could be extended to other EU countries, but with higher cost and lower efficiency. Finally, as the reduction in unemployment is based on the extension of non-tradable services, we suggest alternative policies that reach the same goal without increasing inequality
Circulation et qualification des discours : Conflictualités dans les espaces publics (1): Introduction
No full textInternational audienceEn proposant un cadrage théorique sur la notion d'"espace public", cet article introduit le numéro 47 de la revue "Etudes de communication", numéro qui porte sur la manière dont certains discours, représentations, idéologies naissent, vivent, circulent et se reconfigurent au gré des espaces publics. Ce numéro vise en effet notamment à interroger les modes de circulation et de (ré)appropriation des discours entre différentes arènes et la manière dont ils y sont caractérisés et (dis)qualifiés
La mémoire des figures impériales chez Claudien
No full textInternational audienceSeveral references to earlier emperors can be found in Claudian’s politic poems addressed to Emperor Honorius ; among them are Theodosius, his father, and Trajan, the model for the optimus princeps. This paper aims at analysing how the poet makes use of these references to show the very young Prince of the West what a good emperor is and to legitimatize him (and, at the same time, to legitimatize Stilicho’s place, which has no legal basis) : to achieve this goal, Claudian draws on the double idea of the dynastic transfer of imperial power and the choice of the best possible man. Analysing this allows a better understanding of the functioning of the imperial panegyric, which goes beyond the mere praise in Claudian’s poetry : it creates and shapes the reality it describes – and so the figure of the Prince – in a performative way. The chronological perspective of this study shows also how Claudian’s discourse evolves as Honorius grows from childhood to maturity.Les poèmes politiques que Claudien a écrits pour l’Empereur Honorius sont émaillés de références à des empereurs antérieurs, parmi lesquels Théodose, son père, et Trajan, modèle achevé de l’optimus princeps. L’objet de cet article est d’étudier comment, au travers de ces références, le poète entreprend de dessiner pour le tout jeune Prince d’Occident la figure du bon empereur et de définir sa légitimité (ainsi que celle du régent Stilicon, qu’aucune disposition légale ne justifie) entre transmission dynastique du pouvoir et choix du meilleur. Se voit ainsi précisé le fonctionnement du panégyrique impérial, qui ne se limite pas chez Claudien à la simple louange : le discours crée et met en forme sa propre réalité, jusqu’à se faire performatif, et modeler le personnage loué. La perspective chronologique qui a été choisie montre en outre l’évolution du propos de Claudien à mesure qu’Honorius passe de l’enfance à l’âge adulte