Hidden Structure and Function in the Lexicon

How many words are needed to define all the words in a dictionary? Graph-theoretic analysis reveals that about 10% of a dictionary is a unique Kernel of words that define one another and all the rest, but this is not the smallest such subset. The Kernel consists of one huge strongly connected component (SCC), about half its size, the Core, surrounded by many small SCCs, the Satellites. Core words can define one another but not the rest of the dictionary. The Kernel also contains many overlapping Minimal Grounding Sets (MGSs), each about the same size as the Core, each part-Core, part-Satellite. MGS words can define all the rest of the dictionary. They are learned earlier, more concrete and more frequent than the rest of the dictionary. Satellite words, not correlated with age or frequency, are less concrete (more abstract) words that are also needed for full lexical power.Comment: 11 pages, 5 figures, 2 table

A Unified framework for local visual descriptors evaluation

International audienceLocal descriptors are the ground layer of recognition feature based systems for still images and video. We propose a new framework to explain local descriptors. This framework is based on the descriptors decomposition in three levels: primitive extraction, primitive coding and code aggregation. With this framework, we are able to explain most of the popular descriptors in the literature such as HOG, HOF, SURF. We propose two new projection methods based on approximation with oscillating functions basis (sinus and Legendre polynomials). Using our framework, we are able to extend usual descriptors by changing the code aggregation or adding new primitive coding method. The experiments are carried out on images (VOC 2007) and videos datasets (KTH, Hollywood2 and UCF11), and achieve equal or better performances than the literature

Formation à distance ou formation en ligne? Classe hybride ou formation mixte? En route vers une terminologie commune!

Affiche présentée dans le cadre du Colloque de l'ARC, «La culture de la recherche au collégial», dans le cadre du 82e Congrès de l'Acfas, Université Concordia, Montréal, le 14 mai 2014.En 2013, près de 70 % des établissements d’enseignement supérieur américains considéraient la formation en ligne comme une stratégie importante de leur développement alors que 10 ans auparavant, le taux était inférieur à 50 %. Cet engouement se manifeste concrètement par une augmentation importante non seulement de l’offre de cours, mais aussi de la recherche dans le domaine. Malheureusement, ce développement rapide ne se fait pas sans heurts. Les termes utilisés en français pour désigner les types de formation en ligne se multiplient à grande vitesse. Or, certains veulent dire la même chose alors que d'autres renvoient à plusieurs définitions différentes. Il apparaît donc important de faire une pause pour voir comment on pourrait mieux structurer le langage utilisé dans la formation à distance et en ligne. À partir d’une approche d’analyse des écrits scientifiques sur les thèmes clés dans ce domaine, nous proposons un cadre de référence terminologique qui pourra servir dans les recherches futures ainsi que pour la formation des maîtres

Trust Management within Virtual Communities: Adaptive and Socially-Compliant Trust Model

21 pagesRecent years have witnessed increasing interest of people in sharing, collaborating and interacting in many different ways among new social structures called Virtual Communities (VC). They represent aggrega- tions of entities with common interests, goals, practices or values. VCs are particularly complex environments wherein trust became, rapidly, a prerequisite for the decision-making process, and where traditional trust establishment techniques are regularly challenged. In our work we are considering how individual and collective trust policies can be managed, adapted and combined. To this aim, we propose an Adaptive and Socially-Compliant Trust Management System (ASC-TMS) based on multi-agent technologies. In this framework, policies are used as concrete implementations of trust models in order to specify both (i) user-centred (i.e. personal) and community-centred (i.e. collective) trust requirements. Agents are used to manage and combine these different policies in a decentralized and flexible way. We describe the functionalities and the architecture that supports them and discuss also a prototype implementation

Applying semantic web technologies to context modeling in ambient intelligence

http://www.emse.fr/~picard/publications/sorici13percam.pdfInternational audienceRepresentation and reasoning about context information is a main area of research in Ambient Intelligence (AmI). Given the openness and decentralization of many AmI applications, we argue that usage of se- mantic web technologies for context modeling brings advantages in terms of standards, uniform representation and expressive reasoning. We present an approach for modeling of context information which builds and improves upon related lines of work (SOUPA, CML, annotated RDF). We provide a formalization of the model and an innovative realization using the latest proposals for semantic web standards like RDF and SPARQL. A commonly encountered ambient intelligence scenario showcases the approach

Organisation multi-agent pour la gouvernance de systèmes Machine-to-Machine

http://www.emse.fr/~picard/publications/persson11jfsma.pdfInternational audienceLe paradigme Machine-to-Machine (M2M) implique des appareils (capteurs, effecteurs) interagissant pour fournir des services localisés dans le monde physique. Avec la maturité du M2M, émerge une demande grandissante pour des solutions mutualisées dans lesquelles les applications peuvent partager un ensemble commun d'appareils. Dans ce contexte, le projet SensCity propose une infrastructure pour mettre en oeuvre des applications à l'échelle de la ville, ce qui nécessite de fournir des moyens de gouvernance agile pour prendre en compte l'extensibilité du système (ie. scalability). Nous proposons d'utiliser les technologies multi-agents pour répondre à cette problématique. Selon cette approche, la stratégie de gouvernance est exprimée par une organisation multi-agent à l'aide du framework organisationnel MOISE. Nous illustrons notre proposition par un système de gestion intelligente du strationnement

Gestion de la confiance et intégration des exigences sociales au sein de communautés virtuelles

http://www.emse.fr/~picard/publications/yaich11jfsma.pdfInternational audienceLa confiance est devenue un facteur clé des processus de décision au sein de communautés virtuelles. Le caractère ouvert et décentralisé de ces environnements couplés à leur dimension sociale défient les mécanismes actuelles de gestion de la confiance. Notamment pour ce qui concerne la gestion et l'intégration des exigences de confiance des utilisateurs et ceux de leurs communautés. Afin de répondre à ce problème, nous proposons SC-TMS, un système de gestion de la confiance adaptatif basé sur le principe de conformité sociale [4]. En nous appuyant sur les technologies multi-agents, des politiques de confiance sont utilisées pour spécifier à la fois les modèles de confiance centrés utilisateur et les modèles centrés communauté. Les agents y sont utilisés pour gérer et combiner ces différentes politiques de manière flexible et décentralisée. Nous décrivons les fonctionnalités et l'architecture qui les mettent en oeuvre et discutons de leur implémentation

Mechanical behaviour of iron oxide scale: Experimental and numerical study

2nd International Conference on Tribology in Manufacturing Processes (ICTMP2004), Nyborg, Denmark, June 15-18, 2004International audienceThe paper addresses the identification of constitutive parameters of thick, brittle layers on metal substrates. Application is to the iron oxide behaviour during hot rolling processes of steel, where oxide scale breaking and embedding is one of the major causes of surface defects. Contact management of a FEM software has been adapted in order to address the transitions corresponding to transverse oxide fracture, along with two other mechanisms, namely delamination and interfacial stick/slip. It is applied to the hot strip rolling process to show pre-bite cracking and its consequences ("micro-extrusion" of the metal). To approximate the stress state prevailing at roll bite entry, the Four-Point Hot Bending Test (4PHBT) has been selected for the measurement of oxide properties. Oxidation is made in situ in the test rig under conditions similar to a hot strip mill (HSM) environment. Comparison of load-deflection curves for oxidized and non-oxidized samples allows the mechanical properties of the oxide to be determined. Above a critical temperature T-c - around 700 degrees C, but depending on strain rate - the oxide is ductile (with a very narrow plastic strain range, epsilon(p) < 10(-2)) and elastic-viscoplastic (EVP) constitutive parameters are identified numerically. Below T-c, brittleness is manifested by an array of transverse, through-thickness cracks. Acoustic emission (AE) has been used to help detect the onset of fracture, while numerical simulation gives the critical fracture stress at the corresponding point of the load-deflection curve. Results for four low carbon steel grades are compared

Behaviour of oxide scales in hot steel strip rolling

International audienceThe behaviour of oxide scales in the finishing Hot Strip Mill is simulated by the hot Plane Strain Compression Test (PSCT). Compared with the ideal case of homogeneous plastic co-deformation of the oxide layer and the underlying metal, different types of defects are described: delamination at the interface or within the oxide layer; interfacial plastic instability due to the jump of the mechanical properties; perpendicular, through-thickness cracks where the axial strain parallel to the interface dominates, followed by micro-extrusion of metal between the fragments; oblique cracks followed by sliding along the lips, where shear dominates. The Finite Element Method (FEM) is used to bring elements of interpretation, as to which conditions determine each mechanism. Conclusions for the behaviour in hot rolling are sketche

Grounding Abstract Word Definitions In Prior Concrete Experience

Longman’s Dictionary of Contemporary English (LDOCE) and Cambridge International Dictionary of English (CIDE) have a defining vocabulary of 2000 words from which most but not all of the words are defined. We developed an algorithm, applicable to any dictionary, for recursively deleting words not used in any definition until the corpus is reduced to a subset – a grounding kernel – from which all the words of the complete dictionary are reachable by definition alone. We compared LDOCE’s and CIDE’s defining vocabulary (DV) and grounding kernel (GK) against the rest of its words, on (1) concreteness, (2) imagery and (3) age of acquisition based on the MRC psycholinguistic database [Wilson 1988]. Both GK and DV proved significantly higher on all three scales (p<0.001) for all but 2 of the 12 comparisons (no difference in concreteness in LDOCE for either GK or DV). The difference was also consistently greater using our automatically computed GK than using the DV defined by the compilers of LDOCE and CIDE