24 research outputs found

    Visual Representations Is Lexical Learning Environments: Application To The Alexia System

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    Cognition-based arguments in support of using multimedia aids for the learning of vocabulary have so far offered only an imprecise, general framework. CALL experimentalists have also tried to establish the effectiveness of multimedia for vocabulary learning, but their attempts reveal that the underlying representations have not been clearly defined. After reviewing these points, we propose criteria for evaluating the quality of a visual representation in a lexical environment. These criteria are then used to discuss visual representations in paper and electronic dictionaries and in CALL environments. A kind of confusion has been made between multimedia and nonverbal knowledge. Hence visual representations are scarce and limited to concrete words. One way to extend multimedia in lexical learning is to rely on linguistic knowledge and build lexical networks. We present the ALEXIA system, a lexical learning environment for French as a second/foreign language. We detail its network module which can automatically build graphs of some lexical semantic relations. It is a first step for offering learners representations they can easily interpret. Visual representations which can cover a significant part of the lexicon are computable, extendable and interactive

    Lexical comprehension and production in Alexia system

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    In language learning, vocabulary is very important. Studies have shown that the dictionary is used very often in a written comprehension task. However, its utility is not always obvious. In this paper we discuss the improvements electronic dictionaries can provide compared to classical paper ones. In lexical access, they help the learner by making the relevant information selection and research easier and then improve the efficiency of usage. Our system, Alexia, contains specific lexical information for learners. In lexical production, computers gives us large possibilities with automatic processing. We will see how we use an analyser and a parser in order to make pedagogical new style activities

    Constraints on the structure and seasonal variations of Triton's atmosphere from the 5 October 2017 stellar occultation and previous observations

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    Context. A stellar occultation by Neptune's main satellite, Triton, was observed on 5 October 2017 from Europe, North Africa, and the USA. We derived 90 light curves from this event, 42 of which yielded a central flash detection. Aims. We aimed at constraining Triton's atmospheric structure and the seasonal variations of its atmospheric pressure since the Voyager 2 epoch (1989). We also derived the shape of the lower atmosphere from central flash analysis. Methods. We used Abel inversions and direct ray-tracing code to provide the density, pressure, and temperature profiles in the altitude range similar to 8 km to similar to 190 km, corresponding to pressure levels from 9 mu bar down to a few nanobars. Results. (i) A pressure of 1.18 +/- 0.03 mu bar is found at a reference radius of 1400 km (47 km altitude). (ii) A new analysis of the Voyager 2 radio science occultation shows that this is consistent with an extrapolation of pressure down to the surface pressure obtained in 1989. (iii) A survey of occultations obtained between 1989 and 2017 suggests that an enhancement in surface pressure as reported during the 1990s might be real, but debatable, due to very few high S/N light curves and data accessible for reanalysis. The volatile transport model analysed supports a moderate increase in surface pressure, with a maximum value around 2005-2015 no higher than 23 mu bar. The pressures observed in 1995-1997 and 2017 appear mutually inconsistent with the volatile transport model presented here. (iv) The central flash structure does not show evidence of an atmospheric distortion. We find an upper limit of 0.0011 for the apparent oblateness of the atmosphere near the 8 km altitude.J.M.O. acknowledges financial support from the Portuguese Foundation for Science and Technology (FCT) and the European Social Fund (ESF) through the PhD grant SFRH/BD/131700/2017. The work leading to these results has received funding from the European Research Council under the European Community's H2020 2014-2021 ERC grant Agreement nffi 669416 "Lucky Star". We thank S. Para who supported some travels to observe the 5 October 2017 occultation. T.B. was supported for this research by an appointment to the National Aeronautics and Space Administration (NASA) Post-Doctoral Program at the Ames Research Center administered by Universities Space Research Association (USRA) through a contract with NASA. We acknowledge useful exchanges with Mark Gurwell on the ALMA CO observations. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium).Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. J.L.O., P.S.-S., N.M. and R.D. acknowledge financial support from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award to the Instituto de Astrofisica de Andalucia (SEV-2017-0709), they also acknowledge the financial support by the Spanish grant AYA-2017-84637-R and the Proyecto de Excelencia de la Junta de Andalucia J.A. 2012-FQM1776. The research leading to these results has received funding from the European Union's Horizon 2020 Research and Innovation Programme, under Grant Agreement no. 687378, as part of the project "Small Bodies Near and Far" (SBNAF). P.S.-S. acknowledges financial support by the Spanish grant AYA-RTI2018-098657-J-I00 "LEO-SBNAF". The work was partially based on observations made at the Laboratorio Nacional de Astrofisica (LNA), Itajuba-MG, Brazil. The following authors acknowledge the respective CNPq grants: F.B.-R. 309578/2017-5; R.V.-M. 304544/2017-5, 401903/2016-8; J.I.B.C. 308150/2016-3 and 305917/2019-6; M.A. 427700/20183, 310683/2017-3, 473002/2013-2. This study was financed in part by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior -Brasil (CAPES) -Finance Code 001 and the National Institute of Science and Technology of the e-Universe project (INCT do e-Universo, CNPq grant 465376/2014-2). G.B.R. acknowledges CAPES-FAPERJ/PAPDRJ grant E26/203.173/2016 and CAPES-PRINT/UNESP grant 88887.571156/2020-00, M.A. FAPERJ grant E26/111.488/2013 and A.R.G.Jr. FAPESP grant 2018/11239-8. B.E.M. thanks CNPq 150612/2020-6 and CAPES/Cofecub-394/2016-05 grants. Part of the photometric data used in this study were collected in the frame of the photometric observations with the robotic and remotely controlled telescope at the University of Athens Observatory (UOAO; Gazeas 2016). The 2.3 m Aristarchos telescope is operated on Helmos Observatory by the Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing of the National Observatory of Athens. Observations with the 2.3 m Aristarchos telescope were carried out under OPTICON programme. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 730890. This material reflects only the authors views and the Commission is not liable for any use that may be made of the information contained therein. The 1. 2m Kryoneri telescope is operated by the Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing of the National Observatory of Athens. The Astronomical Observatory of the Autonomous Region of the Aosta Valley (OAVdA) is managed by the Fondazione Clement Fillietroz-ONLUS, which is supported by the Regional Government of the Aosta Valley, the Town Municipality of Nus and the "Unite des Communes valdotaines Mont-Emilius". The 0.81 m Main Telescope at the OAVdA was upgraded thanks to a Shoemaker NEO Grant 2013 from The Planetary Society. D.C. and J.M.C. acknowledge funds from a 2017 'Research and Education' grant from Fondazione CRT-Cassa di Risparmio di Torino. P.M. acknowledges support from the Portuguese Fundacao para a Ciencia e a Tecnologia ref. PTDC/FISAST/29942/2017 through national funds and by FEDER through COMPETE 2020 (ref. POCI010145 FEDER007672). F.J. acknowledges Jean Luc Plouvier for his help. S.J.F. and C.A. would like to thank the UCL student support observers: Helen Dai, Elise Darragh-Ford, Ross Dobson, Max Hipperson, Edward Kerr-Dineen, Isaac Langley, Emese Meder, Roman Gerasimov, Javier Sanjuan, and Manasvee Saraf. We are grateful to the CAHA, OSN and La Hita Observatory staffs. This research is partially based on observations collected at Centro Astronomico HispanoAleman (CAHA) at Calar Alto, operated jointly by Junta de Andalucia and Consejo Superior de Investigaciones Cientificas (IAA-CSIC). This research was also partially based on observation carried out at the Observatorio de Sierra Nevada (OSN) operated by Instituto de Astrofisica de Andalucia (CSIC). This article is also based on observations made with the Liverpool Telescope operated on the island of La Palma by Liverpool John Moores University in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias with financial support from the UK Science and Technology Facilities Council. Partially based on observations made with the Tx40 and Excalibur telescopes at the Observatorio Astrofisico de Javalambre in Teruel, a Spanish Infraestructura Cientifico-Tecnica Singular (ICTS) owned, managed and operated by the Centro de Estudios de Fisica del Cosmos de Aragon (CEFCA). Tx40 and Excalibur are funded with the Fondos de Inversiones de Teruel (FITE). A.R.R. would like to thank Gustavo Roman for the mechanical adaptation of the camera to the telescope to allow for the observation to be recorded. R.H., J.F.R., S.P.H. and A.S.L. have been supported by the Spanish projects AYA2015-65041P and PID2019-109467GB-100 (MINECO/FEDER, UE) and Grupos Gobierno Vasco IT1366-19. Our great thanks to Omar Hila and their collaborators in Atlas Golf Marrakech Observatory for providing access to the T60cm telescope. TRAPPIST is a project funded by the Belgian Fonds (National) de la Recherche Scientifique (F.R.S.-FNRS) under grant PDR T.0120.21. TRAPPIST-North is a project funded by the University of Liege, and performed in collaboration with Cadi Ayyad University of Marrakesh. E.J. is a FNRS Senior Research Associate

    Selva Thierry, Ressources et activités pédagogiques dans un environnement informatique d'aide à l'apprentissage lexical du français langue seconde. Thèse de l'université de Besançon, 29 octobre 1999

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    Selva Thierry. Selva Thierry, Ressources et activités pédagogiques dans un environnement informatique d'aide à l'apprentissage lexical du français langue seconde. Thèse de l'université de Besançon, 29 octobre 1999. In: Sciences et techniques éducatives, volume 6 n°2, 1999. p. 450

    Utilisation de dictionnaire : apport de l'informatique dans les dictionnaires pour apprenants, projet Alexia

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    Des études ont montré que les dictionnaires papiern'étaient pas toujours d'une réelle utilité dans unetâche de compréhension écrite. Sont mis en cause notammentle temps de consultation d'un dictionnaire qui, s'il est trop important, nuitvéritablement au processus de lecture. Ainsi, les apprenants butent surles définitions qui sont parfois trop compliquées et quidemandent la consultation en chaîne d'autres articles pour êtrecomprises. Pour remédier à cet état de fait, nous tentonsde montrer comment un dictionnaire électronique peut aider un apprenantdans sa démarche de consultation. Nous évoquerons notamment ledictionnaire électronique de l'environnement informatique Alexia endéveloppant ses spécificités, destinées àguider et à faciliter la sélection d'information et lacompréhension de vocabulaire

    Selva Thierry, Ressources et activités pédagogiques dans un environnement informatique d'aide à l'apprentissage lexical du français langue seconde. Thèse de l'université de Besançon, 29 octobre 1999

    No full text
    Selva Thierry. Selva Thierry, Ressources et activités pédagogiques dans un environnement informatique d'aide à l'apprentissage lexical du français langue seconde. Thèse de l'université de Besançon, 29 octobre 1999. In: Sciences et techniques éducatives, volume 6 n°2, 1999. p. 450

    Ressources et activités pédagogiques dans un environnement d'aide à l'apprentissage lexical du français langue seconde

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    La nature même du média informatique tend à privilégier l'autonomie de l'apprenant lors de l'apprentissage d'une langue étrangère. L'examen des environnements lexicaux existants montre que l'autonomie passe par l'incorporation de ressources lexicales en tant que matériaux d'apprentissage et outils d'aide. La partie centrale de ce travail a été de concevoir les ressources adaptées à cet apprentissage et la manière dont celles-ci s'articulent. L'environnement ALEXIA se compose d'un corpus de textes, d'un dictionnaire comme outil d'aide, d'un dictionnaire personnalisé et d'un module d'activités lexicales. Le corpus, constitué de textes récents comprenant plusieurs niveaux de langue, est centré sur un domaine du français courant maîtrisé par tout natif (travail, emploi, chômage). La modélisation de la base de données lexicales s'appuie sur les résultats des recherches en psycholinguistique, montrant que le lexique mental semble être composé de mots reliés entre eux par des liens de nature sémantique et contextuelle. L'interface pour visualiser ces données tient compte des problèmes d'accès lexicaux et tire parti des possibilités du support informatique pour la présentation des différentes informations nécessaires aux apprenants. Corpus et dictionnaire servent de matériaux pour la génération d'activités lexicales : à base de concordances, elles mettent en jeu les relations sémantiques du dictionnaire. Pour cela, il est nécessaire d'effectuer au préalable un étiquetage morpho-syntaxique et sémantique du corpus. Un système d'aide donne des indications pour permettre à l'apprenant de résoudre les exercices et renforce ainsi le rôle pédagogique de l'environnement. Le dictionnaire personnalisé permet d'organiser les mots sélectionnés par l'apprenant dans les textes lors de lectures. Le travail de catégorisation effectué renforce les liens du lexique mental et favorise ainsi la rétention

    Génération automatique d’activités lexicales. / Automatic Generation of lexical activities in the Alexia system

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    This paper deals with the automatic generation of lexical activities within a computer assisted language learning environment of French as a second language : the ALEXIA system. We intend to show more precisely how the lexical resources which are fully integrated into the system and their use by tools originating from the natural language processing field allow us to generate new computational activities which are both relevant and learner centered. These lexical resources are of paramount importance to facilitate the autonomous learning process. The system however should not be limited to its resources. It should be based also on sound and well defined pedagogical principles which greatly influence its design.Cet article traite de la génération automatique d’activités lexicales au sein d’un environnement informatique d’aide à l’apprentissage lexical du français langue seconde : le système ALEXIA. Plus précisément, nous établissons en quoi les ressources lexicales intégrées au système et leur utilisation par des outils issus du traitement automatique du langage naturel conduisent à générer des activités informatisées d’un type nouveau, pertinentes et adaptées au travail déjà accompli par l’apprenant. Les ressources lexicales s’avèrent indispensables pour favoriser l’apprentissage en autonomie. Cependant, le système ne doit pas se résumer à ses ressources, mais doit s’appuyer sur des principes pédagogiques bien définis qui influent grandement sur sa conception.Selva Thierry, Chanier Thierry. Génération automatique d’activités lexicales. / Automatic Generation of lexical activities in the Alexia system. In: Sciences et techniques éducatives, volume 7 n°2, 2000. pp. 385-411

    Génération automatique d'activités Lexicales dans le système ALEXIA

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    This paper deals with the automatic generation of lexical activities within a computer assisted language learning environment of French as a second language: the ALEXIA system. We intend to show more precisely how the lexical resources which are fully integrated into the system and their use by tools originating from the natural language processing field allow us to generate new computational activities which are both relevant and learner centered. These lexical resources are of paramount importance to facilitate the autonomous learning process. The system however should not be limited to its resources. It should be based also on sound and well defined pedagogical principles which greatly influence its design.Cet article traite de la génération automatique d'activités lexicales au sein d'un environnement informatique d'aide à l'apprentissage lexical du français langue seconde : le système ALEXIA. Plus précisément, nous établissons en quoi les ressources lexicales intégrées au système et leur utilisation par des outils issus du traitement automatique du langage naturel conduisent à générer des activités informatisées d'un type nouveau, pertinentes et adaptées au travail déjà accompli par l'apprenant. Les ressources lexicales s'avèrent indispensables pour favoriser l'apprentissage en autonomie. Cependant, le système ne doit pas se résumer à ses ressources, mais doit s'appuyer sur des principes pédagogiques bien définis qui influe grandement sur sa conception

    Représentation et utilisation de connaissances dans un système d'aide à l'apprentissage lexical

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    Nous présentons dans cet article la manière dont sont structurées et utilisées les informations dans un environnement informatique d'aide à l'acquisition lexicale du français langue seconde : AlexiA. Le système propose une aide en compréhension et en production, ce qui permet à l'apprenant de consolider et de valider le vocabulaire étudié. Nous avons organisé les données lexicales du système, d'une part en fonction des travaux en psycholinguistique sur le lexique mental, et d'autre part en fonction des travaux en linguistique appliquée sur l'acquisition/apprentissage. Nous avons utilisé le formalisme des grammaires d'arbres adjoints pour représenter les données syntaxiques. Ce système est développé sur une plateforme Macintosh à partir d'Hypercard et comprend différents modules en Prolog et en C
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