138 research outputs found
Silicon carbide equipments for process intensification of silicon reactions.
Bluestar Silicones, one of the worldwide leaders in silicones chemistry, proposes a
R&D project, aiming to design new equipment for the transposition of batch to continuous
processes. The safety and environmental issues linked to this type of chemicals, and the
productivity targets as well require innovative technologies characterized by a fair corrosion
resistance and high heat and mass transfer performances. A preliminary prototype of heat
exchanger reactor made of silicon carbide plates has been developed by the LGC in
collaboration with a SME specialist of SiC, Boostec. It has allowed the pilot feasibility with
some reactions of industrial interest for a Bluestar Silicones to be highlighted. Now, it is
necessary to pursue this effort and beyond the feasibility step to go on up to the design of an
industrial reactor. This project corresponds to a programme of innovative process development
in order to design cleaner, safer and less consuming devices
Conception dâune plateforme dâapprentissage en ligne en algĂšbre et en gĂ©omĂ©trie : prise en compte et apports de modĂšles didactiques
This article presents the design of a theoretical and methodological framework for the didactic design of a learning environment: a learning platform in mathematics for cycle 4 students (aged 12 to 15). We cross several approaches to build didactic models and their computer representation: a model of the knowledge involved in the platform, a model of the learner's reasoning, and a model of learning paths adapted to the student's learning needs. We illustrate this approach on two themes from two mathematical domains, the solving of first-degree equations in algebra and the construction of triangles in geometry.Cet article prĂ©sente la dĂ©finition dâun cadre thĂ©orique et mĂ©thodologique pour la conception didactique dâun environnement informatique pour lâapprentissage humain (EIAH) : une plateforme dâapprentissage en mathĂ©matiques Ă destination dâĂ©lĂšves de cycle 4 (Ă©lĂšves de 12 Ă 15 ans). Nous croisons plusieurs approches thĂ©oriques pour construire des modĂšles didactiques et leur reprĂ©sentation informatique : un modĂšle du savoir en jeu dans la plateforme, un modĂšle du raisonnement de lâapprenant et un modĂšle des parcours dâapprentissage adaptĂ©s aux besoins dâapprentissage de lâĂ©lĂšve. Nous illustrons cette conception sur deux thĂšmes issus de deux domaines mathĂ©matiques, la rĂ©solution dâĂ©quations du premier degrĂ© en algĂšbre et la construction de triangles en gĂ©omĂ©trie
Les documents scientifiques informels: un patrimoine peu exploré, témoin de la construction des savoirs
L'objectif du projet ECRITO Ă©tait de contribuer Ă prĂ©server et Ă valoriser les documents scientifiques produits quotidiennement par les chercheurs de Midi-PyrĂ©nĂ©es, en amont des publications formelles : non seulement les articles, communications ou monographies, qui constituent la partie visible de la recherche, mais aussi tous les matĂ©riaux et informations accumulĂ©s par les chercheurs, et sur la base desquels se construit leur travail. Ces matĂ©riaux sont de types trĂšs divers : littĂ©rature " grise " (rapports, mĂ©moires, documentation techniques...), documents textuels " informels " (carnets, notes, brouillons, correspondances, cahiers de laboratoires), corpus visuels, sonores ou multimĂ©dia (campagnes photographiques, campagnes d'enquĂȘtes, enregistrements audio ou vidĂ©o), donnĂ©es Ă©lectroniques (bases de donnĂ©es, fichiers informatiques), etc. Le projet visait Ă©galement Ă prolonger, de maniĂšre exploratoire, le questionnement sur le patrimoine scientifique Ă partir des traces matĂ©rielles produites quotidiennement par les chercheurs dans leurs activitĂ©s de recherche. Ces traces reprĂ©sentent en effet une fenĂȘtre irremplaçable sur la science en train de se construire : elles permettent de rendre visible et comprĂ©hensible le processus habituellement dissimulĂ© de production de la science, ce qui constitue un enjeu scientifique et pĂ©dagogique fondamental
Evolution of a low convergence collisional orogen: a review of Pyrenean orogenesis
The Pyrenees is a collisional orogen built by inversion of an immature rift system during convergence of the Iberian and European plates from Late Cretaceous to late Cenozoic. The full mountain belt consists of the pro-foreland southern Pyrenees and the retro-foreland northern Pyrenees, where the inverted lower Cretaceous rift system is mainly preserved. Due to low overall convergence and absence of oceanic subduction, this orogen preserves one of the best geological records of early orogenesis, the transition from early convergence to main collision and the transition from collision to post-convergence. During these transitional periods major changes in orogen behavior reflect evolving lithospheric processes and tectonic drivers. Contributions by the OROGEN project have shed new light on these critical periods, on the evolution of the orogen as a whole, and in particular on the early convergence stage. By integrating results of OROGEN with those of other recent collaborative projects in the Pyrenean domain (e.g., PYRAMID, PYROPE, RGF-Pyrénées), this paper offers a synthesis of current knowledge and debate on the evolution of this immature orogen as recorded in the synorogenic basins and fold and thrust belts of both the upper European and lower Iberian plates. Expanding insight on the role of salt tectonics at local to regional scales is summarised and discussed. Uncertainties involved in data compilation across a whole orogen using different datasets are discussed, for example for deriving shortening values and distribution
IRIS â Institut de recherche interdisciplinaire sur les enjeux sociaux, sciences sociales, politiques, santĂ©
Jonathan Friedman, directeur dâĂ©tudesNatacha GagnĂ©, professeure agrĂ©gĂ©e Ă lâUniversitĂ© dâOttawaPaula Lopez-Caballero, postdoctorante CERI-Sciences PoMarie SalaĂŒn, maĂźtre de confĂ©rences Ă lâUniversitĂ© Paris-V/Descartes Questions autochtones contemporaines Cette quatriĂšme annĂ©e du sĂ©minaire a vu lâorganisation de douze sĂ©ances et dâune table ronde, du 4 novembre 2010 au 3 fĂ©vrier 2011. En moyenne, le sĂ©minaire a regroupĂ© une trentaine de participants, ce qui tĂ©moigne dâun intĂ©rĂȘt grandissant po..
Rapid response to the M_w 4.9 earthquake of November 11, 2019 in Le Teil, Lower RhĂŽne Valley, France
On November 11, 2019, a Mw 4.9 earthquake hit the region close to Montelimar (lower RhĂŽne Valley, France), on the eastern margin of the Massif Central close to the external part of the Alps. Occuring in a moderate seismicity area, this earthquake is remarkable for its very shallow focal depth (between 1 and 3 km), its magnitude, and the moderate to large damages it produced in several villages. InSAR interferograms indicated a shallow rupture about 4 km long reaching the surface and the reactivation of the ancient NE-SW La Rouviere normal fault in reverse faulting in agreement with the present-day E-W compressional tectonics. The peculiarity of this earthquake together with a poor coverage of the epicentral region by permanent seismological and geodetic stations triggered the mobilisation of the French post-seismic unit and the broad French scientific community from various institutions, with the deployment of geophysical instruments (seismological and geodesic stations), geological field surveys, and field evaluation of the intensity of the earthquake. Within 7 days after the mainshock, 47 seismological stations were deployed in the epicentral area to improve the Le Teil aftershocks locations relative to the French permanent seismological network (RESIF), monitor the temporal and spatial evolution of microearthquakes close to the fault plane and temporal evolution of the seismic response of 3 damaged historical buildings, and to study suspected site effects and their influence in the distribution of seismic damage. This seismological dataset, completed by data owned by different institutions, was integrated in a homogeneous archive and distributed through FDSN web services by the RESIF data center. This dataset, together with observations of surface rupture evidences, geologic, geodetic and satellite data, will help to unravel the causes and rupture mechanism of this earthquake, and contribute to account in seismic hazard assessment for earthquakes along the major regional CĂ©venne fault system in a context of present-day compressional tectonics
Articuler les dimensions épistémologiques, didactiques et institutionnelles d'un exercice pour une indexation dans un EIAH
International audienceCet article présente une modélisation d'un exercice de mathématiques permettant à la fois d'en décrire la nature, de le caractériser épistémologiquement et didactiquement, et si nécessaire, d'affiner cette caractérisation en le situant dans une ou plusieurs institutions. Ce travail s'inscrit dans la construction d'un processus d'indexation et de recherche de ressources pour l'enseignant, directement ou dans le cadre d'un EIAH
Descripteurs didactiques d'exercices de mathématiques : catégorisation ; utilité et utilisabilité d'un modÚle
International audienceWe aim at questioning the mathematical resource dissemination, and more particularly their description. We analyze the requirements of teacher and researcher and we present a model, which enables us to get a description based on didactics criteria.Cette contribution s'inscrit dans le questionnement relatif Ă la diffusion des ressources et plus prĂ©cisĂ©ment la description de celles-ci. Nous prĂ©sentons le lien entre un modĂšle, conçu par nous, de description didactique d'exercices de mathĂ©matiques et le rĂ©sultat d'une enquĂȘte sur les besoins d'utilisateurs en matiĂšre de description d'exercices de mathĂ©matiques. Toujours Ă partir de cette enquĂȘte nous proposons aussi une liste de mĂ©tadonnĂ©es pouvant ĂȘtre associĂ©e Ă un exercice de mathĂ©matiques
Descripteurs didactiques d'exercices de mathématiques : catégorisation ; utilité et utilisabilité d'un modÚle
International audienceWe aim at questioning the mathematical resource dissemination, and more particularly their description. We analyze the requirements of teacher and researcher and we present a model, which enables us to get a description based on didactics criteria.Cette contribution s'inscrit dans le questionnement relatif Ă la diffusion des ressources et plus prĂ©cisĂ©ment la description de celles-ci. Nous prĂ©sentons le lien entre un modĂšle, conçu par nous, de description didactique d'exercices de mathĂ©matiques et le rĂ©sultat d'une enquĂȘte sur les besoins d'utilisateurs en matiĂšre de description d'exercices de mathĂ©matiques. Toujours Ă partir de cette enquĂȘte nous proposons aussi une liste de mĂ©tadonnĂ©es pouvant ĂȘtre associĂ©e Ă un exercice de mathĂ©matiques
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