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Basic quantum algebra
No full textThis is an introduction to quantum algebra, from a geometric perspective. The classical spaces X, such as the Lie groups, homogeneous spaces, or more general manifolds, are described by various algebras A, defined over various fields F . These algebras A satisfy a commutativity type condition, and the general idea is that of lifting this condition, and calling quantum spaces the underlying space-like objects X. One problem comes from the fact that different fields F lead, via different algebras A, to different classes of quantum spaces X. Our aim here is to identify and put at the center of the presentation those quantum spaces X which do not depend on the choice of F
« Outils au service de la production écrite » : quelle articulation avec l’enseignement du lexique à l’école élémentaire ? Mohammed Bouchekourte, Nathalie Denizot et Solenn Petrucci (dir.)
No full textInternational audienceIn France, writing is a fundamental skill that is rarely taught or assessed at school. What's more, the study of language remains poorly integrated with the activity of written production. We study a book entitled “outils pour produire des écrits” (tools for producing writing) aimed at elementary school teachers, as a tool likely to influence teachers' practices to modify their knowledge and conceptions of the teaching of writing. We question the notion of tool and analyze the book's proposals, focusing on the writing-lexic articulation.Écrire est une compétence fondamentale qui reste en France peu enseignée et peu évaluée à l’école. En outre, l’étude de la langue reste peu intégrée à l’activité de production écrite. Nous étudions un ouvrage intitulé « outils pour produire des écrits » à destination des enseignants d’école élémentaire, comme outil susceptible d’influencer les pratiques des enseignants pour modifier leurs connaissances et leurs conceptions sur l’enseignement de l’écriture. Nous interrogeons la notion d’outil et analysons les propositions de cet ouvrage en nous focalisant sur l’articulation rédaction-lexique
Trois conseils pour limiter le stress au travail - The Conversation France: https://theconversation.com/trois-conseils-pour-limiter-le-stress-au-travail-258424?utm_source=clipboard&utm_medium=bylinecopy_url_button
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L'OuLiPo à l'ère de l'intelligence artificielle générative obsolescence programmée ou nouveau souffle créatif ?
No full textComment écrire avec une machine sans renoncer à la littérature ? Ce mémoire interroge les relations entre les contraintes oulipiennes et les modèles d’intelligence artificielle générative, en articulant une analyse théorique rigoureuse à une série d’expérimentations concrètes. De Queneau à GPT‑4, il explore la plasticité des formes, le rôle mouvant de l’auteur, la participation accrue du lecteur et l’émergence de nouvelles pratiques créatives. En traversant l’histoire des écritures contraintes, en testant les limites des IA dans la production littéraire, et en esquissant des formes collaboratives inédites, il pose les bases d’un dialogue entre humanisme formel et automatisme moderne
Petites gares ferroviaires et intermodalités : quelles innovations pour l’aménagement des interfaces entre train léger et territoires peu denses ?
No full textInternational audienc
Oracle-Orgeval, Long-term Research observatory of the critical zone
No full textInternational audienceThe Orgeval Long-term Research Observatory, part of the French critical zone network (OZCAR RI), is a 104 km² agricultural catchment, located 70 km east of Paris, in France. The Orgeval catchment is representative of intensive agriculture (80 % of its total area), the main land use in the Seine river basin. For more than 50 years, both quantity and quality of water are monitored throughout the catchment, from sub-hourly to yearly time scales. This rich dataset allows improving the understanding of critical zone structure and reactivity, in a holistic and interdisciplinary approach. Specific basic and applied research topics relate to extreme hydrological events, agricultural tile drainage, land use planning, and more generally the evolution of agricultural activities facing climate change and urban growth. The Orgeval research observatory is a unique testbed to investigate the functioning and evolution of the Critical Zone. Multidisciplinary approaches are implemented thanks to collaborations between research institutes and universities, combining knowledge and methods from different disciplines, such as hydrology, ecology, biogeochemistry, geophysics and socioeconomics. Created in 1962, the observatory was initially devoted to study floods and weathering research questions. Since then, is evolved towards other societal and environmental topics. Initiated in 1975, lots of monitoring and research was dedicated to diffuse agricultural pollution, especially nitrates, which contributed to a better understanding of the interactions between agricultural activities and surface and groundwater quality. Since the 2000’s, research questions opened to pesticides and biology and biodiversity. The Orgeval observatory is also highly adapted to develop technological innovations, such as in situ biochemical monitoring. A multi-scale observation strategy is implemented in both space and time, ranging from local (with more than 80 monitoring sites) to regional scale, and from time-lapse campaigns to high-frequency measurements (from 1 Hz for geophysics to 1 h or 1 week for chemistry), most often with a long-term approach. The main measurements include: Water level and water discharge : at the outlet of each sub-catchment. groundwater level : in piezometers in the riverbanks and in the aquifers. Precipitation : in addition to Météo-France stations. Main weather variables : air temperature, humidity, and radiation. Soil moisture : from the soil surface to a depth of 1.5 meters. Water quality : dissolved organic and inorganic carbon, dissolved gases (O 2 , CO 2 , Rn), major and trace ions, nutrients, but also water, carbon or strontium stable isotopes. This includes the RiverLab prototype, installed in June 2015 at the outlet of Avenelles sub-catchment for high-frequency measurement (every 30 minutes) of the river's chemical composition. Organic and inorganic contaminants : pesticides but also metals and microplastics in surface and groundwater. Ecotoxicological and ecological indices : ecological assessment. Surface and groundwater temperature : using heat as a tracer of surface-groundwater exchanges. Hydrogeophysics : ERT, GPR, seismic, especially in the riparian areas. Borehole core samples and logging : lithofacies description and characterization. Water level and water discharge : at the outlet of each sub-catchment. groundwater level : in piezometers in the riverbanks and in the aquifers. Precipitation : in addition to Météo-France stations. Main weather variables : air temperature, humidity, and radiation. Soil moisture : from the soil surface to a depth of 1.5 meters. Water quality : dissolved organic and inorganic carbon, dissolved gases (O 2 , CO 2 , Rn), major and trace ions, nutrients, but also water, carbon or strontium stable isotopes. This includes the RiverLab prototype, installed in June 2015 at the outlet of Avenelles sub-catchment for high-frequency measurement (every 30 minutes) of the river's chemical composition. Organic and inorganic contaminants : pesticides but also metals and microplastics in surface and groundwater. Ecotoxicological and ecological indices : ecological assessment. Surface and groundwater temperature : using heat as a tracer of surface-groundwater exchanges. Hydrogeophysics : ERT, GPR, seismic, especially in the riparian areas. Borehole core samples and logging : lithofacies description and characterization. All these data support the development and use of numerical models, for scientific questions but also for environmental impact assessment and territorial management. This catchment is used to develop and/or validate numerical methodologies at the headwater catchment scale, in parallel to larger scale modeling (typically for the Seine river basin
A quantitative assessment of the behavior of metallic elements in urban soils exposed to industrial dusts near Dunkerque (northern France)
No full textInternational audienceIn urban and industrialized areas, soil contamination and degradation caused by industrial dust deposition may pose significant health and environmental risks. Generally, the mobility and thus bioavailability of potentially toxic elements (PTEs) are key factors in these issues. In the Dunkerque agglomeration, one of the most industrialized regions in France, the soils are periodically exposed to metallurgical dust fallout, rich in PTEs. However, no study has reported on the behavior of these PTEs once integrated into the soils. The aim of this study is therefore to assess the fate of PTEs in the urban soils of Dunkerque in terms of vertical migration and potential bioavailability.Four soil short cores were collected in the city of Gravelines (Dunkerque agglomeration) along a gradient from industrial emitters to deposition sites. Each soil core was cut into discrete 1 cm sections for PTE concentration analyses (ICP-AES/MS). Single HCl extractions were performed to evaluate PTE mobility in soils and their behavior according to the current soil parameters. For this purpose, key soil properties were identified, including grain-size distribution, mineralogy, pH, cation exchange capacity (CEC), TOC (total organic carbon), calcium carbonates and water contents in addition to the soil chemical composition (XRF, ICP-AES/MS).The studied soils revealed globally low absorbent capacities for pollutants (CEC averaging ), partially counterbalanced by the buffering effect of calcium carbonates (contents ranging from 8 %–30 %). Near the industrial emitters, minor (1 < EF <3) to moderately severe (5 < EF < 10) enrichment factors (EFs) were highlighted for industrial PTE (Cr, Ni, Mo, Mn, Cd and Zn) in the top 3 cm of soils near the industrial emitters. The contamination profiles of these soils are assigned to atmospheric inputs of metallurgical dust. Using a relatively strong leaching reagent (1 M HCl), we estimated a low vertical mobility for Cr, Ni and Mo (average leached ratios < 25 %) in soils, suggesting their association with refractory phases (natural or anthropogenic). In contrast, Mn, Cd and Zn, which are related to industrial and/or urban sources, present a higher mobility (average leached ratios>60 % for Mn and Cd and about 44 % for Zn).Our study points out the stability of industrial PTEs in soils under the current physicochemical conditions (calcareous soils with a slightly basic pH of 7.8). In this context, the monitoring of industrial PTEs in these urban soils is highly recommended, considering (1) the presence of allotment gardens in the vicinity of emitters and (2) the potential evolution of soil conditions due to increasing flood events
Génération de jeux de données pour entraîner un classificateur de sécurité de réseau électrique intelligent de basse tension
No full textInternational audienceLa simulation du pilotage de ressources flexibles distribuées dans les réseaux électriques de basse tension nécessite des outils rapides et fiables pour l'étude de la sécurité de ces réseauxvérifier si les limites (ex : en tension, en courant) du réseau sont respectées. Cette communication décrit les performances de trois types de modèles de classification basés sur les données pour vérifier si l'état opérationnel d'un réseau peut être considéré comme "sûr" ou "non sûr". Le but de ces méthodes est de réduire l'effort computationnel par rapport aux outils classiques d'écoulement de puissance (power flow). Cinq stratégies de génération de données sont proposées pour l'entraînement de ces modèles, ensuite testés avec des scénarios réalistes. Nos résultats montrent que les modèles de type réseaux de neurones ont des performances acceptables à coût de calcul réduit. Notre étude souligne l'importance de produire des jeux de données synthétiques qui visent à une meilleure généralisation en inférence, avec des tailles de jeux de données réduites pour l'entraînement
