Knowledge Acquisition for Learner Modelling in Second Language Learning

The results of past studies in Error Analysis in applied linguistics and the experiences of developers of intelligent tutoring systems in learner modelling have influenced our definition of a new structure, called an "applicable rule", that can be used to help diagnose and to represent a learner's performance in second language learning systems. Based on this structure a prototype interface has been designed to acquire the knowledge that it must contain. The results of experiments with this interface, to validate and to fill it, have been instrumental in refining its structure, pointing out the difficulties of transforming it into an automated acquisition device, and in indicating its potential as a teaching device

Genetic-algorithm discovery of a direct-gap and optically allowed superstructure from indirect-gap Si and Ge semiconductors

Combining two indirect-gap materials-with different electronic and optical gaps-to create a direct gap material represents an ongoing theoretical challenge with potentially rewarding practical implications, such as optoelectronics integration on a single wafer. We provide an unexpected solution to this classic problem, by spatially melding two indirect-gap materials (Si and Ge) into one strongly dipole-allowed direct-gap material. We leverage a combination of genetic algorithms with a pseudopotential Hamiltonian to search through the astronomic number of variants of Si /Ge /.../Si /Ge superstructures grown on (001) Si Ge . The search reveals a robust configurational motif-SiGe Si Ge SiGe on (001) Si Ge substrate (x≤0.4) presenting a direct and dipole-allowed gap resulting from an enhanced Γ-X coupling at the band edges. © 2012 American Physical Society

Substitutional nickel impurities in diamond: decoherence-free subspaces for quantum information processing

The electronic and magnetic properties of a neutral substitutional nickel (Ni$_s^0$) impurity in diamond are studied using density functional theory in the generalized gradient approximation. The spin-one ground state consists of two electrons with parallel spins, one located on the nickel ion in the $3d^9$ configuration and the other distributed among the nearest-neighbor carbons. The exchange interaction between these spins is due to $p-d$ hybridization and is controllable with compressive hydrostatic or uniaxial strain, and for sufficient strain the antiparallel spin configuration becomes the ground state. Hence, the Ni impurity forms a controllable two-electron exchange-coupled system that should be a robust qubit for solid-state quantum information processing

L'exemple d'un corpus d'interactions orales spontanées structuré en TEI : quels avantages pour l'interopérabilité, l'analyse et le partage des données de la recherche ?

International audienceno abstrac

Étude comparative du discours adressé à l'enfant et du discours adressé à l'apprenant de français langue étrangère

International audienceno abstrac

Applying Interactive Open Learner Models to Learning Technical Terminology

Abstract. Our work explores an interactive open learner modelling (IOLM) approach where learner diagnosis is considered as an interactive process involving both a computer system and a learner that play symmetrical (to a certain extent) roles and construct together the learner model. The paper presents an application of IOLM for diagnosing and fostering a learner's conceptual understanding in a terminological domain. Based on an experimental study, we discuss computational and educational benefits of IOLM in terms of improving the quality of the obtained learner model and fostering reflective thinking

Input in first and second language acquisition: the case of schwa variation and liaison in French

International audienceno abstrac