HAL-Université de Bretagne Occidentale
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Penser les politiques de formation dans l'enseignement supérieur : contexte, enjeux et perspectives de recherche
No full textInternational audienceAprès avoir repositionné notre webinaire dans l'ensemble des nombreux espaces de discussion scientifique actuellement consacrés à l'enseignement supérieur, nous proposons de focaliser l'attention sur ce qui constitue le thème principal de ce webinaire : les politiques de formation de l'enseignement supérieur. Il s'agit notamment de discuter la notion de "politique de formation" à partir d'un questionnement sur les évolutions réglementaires, institutionnelles, organisationnelles, budgétaires, professionnelles, curriculaires et pédagogiques qui, depuis la loi LRU, contribuent à la redéfinition des enjeux, des modalités et des objectifs des formations du supérieur. Cet exposé est aussi l'occasion d'évoquer les différentes perspectives de recherche qui vont être abordées, de manière plus focalisée, dans les séances à venir du webinaire
Behind the scenes of designing and scripting a permaculture workshop to support reflexivity: Behind the scenes of designing and scripting a permaculture workshop to support reflexivity
No full textInternational audienceDespite a plethora of studies describing the impact of collaborative workshops, few explore the process of designing these workshops, from bringing together participants, who often come from diverse backgrounds, to achieving a goal, including how to collaborate during the workshop. In this contribution, we offer feedback on the design and scripting of an immersive workshop aimed at supporting learners' reflexivity by drawing on the mechanism of selective comparison, well known in the field of creativity psychology. In this workshop, higher education students are encouraged to seek inspiration in the principles of permaculture and then adapt it to their initial context to solve their problem. We present the context of our project, our objectives, and the design and scripting process, which proved to be enriching for our teaching practices. Finally, we conclude with a reflective assessment of this design and prototyping experience by analyzing its potential for transferability.Malgré une pléthore de travaux qui décrivent l’impact des ateliers collaboratifs, peu de travaux explorent le processus de conception de ces ateliers allant de la rencontre des participants, provenant souvent d'horizons divers, à la réalisation d’un objectif en passant par la manière de collaborer durant l’atelier. Dans cette contribution, nous proposons un retour d’expérience sur la conception et la scénarisation d’un atelier immersif visant à soutenir la réflexivité des apprenants en s’appuyant sur le mécanisme de la comparaison sélective, bien connu dans le domaine de la psychologie de la créativité. Dans cet atelier, les étudiants de l’enseignement supérieur sont amenés à aller chercher une source d'inspiration dans les principes de la permaculture, puis de l'adapter à leur contexte initial pour résoudre leur problématique. Nous présentons le contexte de notre projet, nos objectifs ainsi que le processus de conception et de scénarisation qui se sont révélés enrichissants pour nos pratiques enseignantes. Enfin, nous concluons par un bilan réflexif de cette expérience de conception et de prototypage en analysant son potentiel de transférabilité
Gap-free GNSS-R wind field reconstruction: A neural mapping scheme and initial validation
No full textInternational audienceSpaceborne Global Navigation Satellite System Reflectometry (GNSS-R) has been widely demonstrated as an effective method for ocean wind speed retrieval. This study explores the feasibility of using track-wise GNSS-R wind products to generate gap-free wind fields. A physics-informed neural mapping scheme, 4DVarNet, is adapted to reconstruct wind fields. Results indicate that the root mean square errors (RMSEs) of the 1-hour, 3-hour, and 6-hour 4DVarNet winds are 1.13 m/s, 1.16 m/s, and 1.24 m/s compared to European Center for Medium-Range Weather Forecast (ECMWF) ERA5 wind products, while 1.40 m/s, 1.41 m/s, and 1.48 m/s are referred to Advanced Microwave Scanning Radiometer-2 (AMSR2) all-weather winds. Spatial and temporal error analyses further confirm the robustness of 4DVarNet-derived winds, with daily RMSEs remaining below 1.6 m/s. Error decomposition reveals discrepancies between ECMWF and GNSS-R winds, which may support future recalibration of GNSS-R wind products or enhancements to ECMWF forecasts. A case study of Super Typhoon Surigae proves that 4DVarNet winds closely align with the International Best Track Archive for Climate Stewardship (IBTrACS) track data. The reconstructed winds detect the peak intensity temporally consistent with IBTrACS data, whereas ECMWF forecasts exhibit a two-day lag. Moreover, asymmetries in Tropical Storm Kompasu are observed, with the radius of maximum wind (Rmax) over the Northeast quadrant 38% larger than that over the Northwest quadrant. Despite the absence of background wind field inputs, 4DVarNet effectively learns wind patterns from ECMWF data and integrates GNSS-R observations to generate gap-free wind mappings, exhibiting strong agreement with ECMWF wind fields. The reconstruction performance is degraded at high winds due to the underestimation of referenced ECMWF ERA5 winds and the small quantity of observations. This limitation could be alleviated through denser GNSS-R observations from multiple missions such as Fengyun-3, Tianmu-1, recently launched HydroGNSS, etc., and other training references with more high winds for improving the representation of 4DVarNet at high winds
L’éthique professionnelle, clé de la confiance des hospitaliers envers leur préparation aux crises ?
No full textInternational audienceTo effectively respond to health crises, hospital staff must be adequately prepared. This study examines how hospital staff perceive health crises and their preparedness. The study uses the concept of professional ethics and trust to improve understanding of the preparedness behaviors. Forty-three semi-structured interviews were conducted with French hospital staff, and a reflective thematic content analysis was applied to the data. The study’s findings show that preparedness for health crises is regarded as a professional responsibility due to a shared professional ethic. This perceived shared ethic fosters trust in colleagues and organizations. These results raise questions about how trust influences the adoption of preparedness behaviors.Pour répondre efficacement aux situations sanitaires exceptionnelles, la préparation des personnels hospitaliers est nécessaire. Cette étude explore leurs représentations associées aux situations sanitaires exceptionnelles et à leur préparation, au travers du prisme de l’éthique professionnelle et de la confiance interpersonnelle et institutionnelle pour mieux comprendre les leviers d’adoption des comportements de préparation. Quarante-trois entretiens semi-directifs ont été menés auprès de personnels hospitaliers franc¸ais, auxquels a été appliquée une analyse de contenu thématique réflexive. Les résultats de l’étude soulignent qu’en raison de l’éthique professionnelle perc¸ue, la préparation aux situations sanitaires exceptionnelles est considérée comme une responsabilité professionnelle. Cette perception d’une éthique par-tagée favorise la confiance envers les collègues et les organisations. Ces résultats questionnent l’influence de cette confiance dans l’adoption de comportements de préparation
Bioinspired bi- or trinuclear FeMoS model complexes for the partial region of FeMo cofactor of nitrogenase
No full textInternational audienceSulfur-rich {FeMo} complexes of low nuclearity ({Fe2Mo}, {FeMo}) can be considered as simple truncated models of the cofactor of Mo‑nitrogenase. They are suitable to address questions concerning the role of the still unclear FeMo cooperativity in the biological N2-reduction process performed by this metallo-enzyme. This review affords a state of the art of the chemistry of di- and tri-heterometallic {FeMoS} complexes. Although well-defined synthetic procedures have been evidenced for the design of such compounds, very few investigations on their activity towards N2 and related substrates have been reported. This shows the interest to develop new light bio-inspired {FeMoS} molecules and to study their reactivity, as well as their redox behaviours, to help to better understand the biological N2-fixation. This approach involving di- and tri- heterometallic {FeMoS} species is a promising field of investigation
Magnetically supramassive and hypermassive compact stars
No full textInternational audienceIt is known that the mass of magnetized relativistic compact star is larger than that of non-magnetized one for the same equation of state and central density, albeit the excess of mass is sizable only if the magnetic fields are strong enough B~10^17-10^18G. Using our recently developed numerical code COCAL, we systematically compute such compact star solutions in equilibrium associated with mixed poloidal and toroidal magnetic fields, and show the magnetically supramassive solutions whose masses exceed by more than 10% of the maximum mass of the static and spherically symmetric solutions. For some extremely strong magnetic field configurations, we also obtain solutions more massive than the maximum mass of the uniformly rotating solutions at the Kepler (mass-shedding) limit, namely magnetically hypermassive solutions
Ellipsoid uncertainty tether model for collision avoidance in a fleet of Remotely Operated Vehicles
No full textInternational audienceDuring collision avoidance, the tether of Remote Operated Vehicle (ROV) is subject to entanglement with obstacles or other ROVs' tether. This specificity renders traditional multi-robot obstacle avoidance approaches inadequate for tethered multi-robot scenarios. This paper proposes a guaranteed ellipsoid model for representing the ROV's tether and its nearby obstacles, enabling an efficient, low-computation collision avoidance method for a fleet of ROVs. The model ensures that if the ellipsoid encompassing the tether remains entirely outside the ellipsoid encompassing an obstacle, there is no risk that the tether collides with it. The approach requires only the two attachment points of the tether and its length, without needing any information about the tether's shape, dynamics, or external disturbances such as underwater currents. A collision avoidance strategy is developed based on potential field methods combined with tether length management. When multiple ROVs are involved, personalities are added to ROV to obtain different behaviors, reducing the likelihood of deadlocks during avoidance maneuvers. Simulations demonstrate the method's effectiveness across various scenarios, and its limitations are also discussed
Long-term monitoring of coastal boulder deposits on Banneg Island: A good proxy for detection of extreme oceanic storms off West Brittany (France)
No full textInternational audienceCoastal boulder deposits (CBD) provide relevant information on coast-erosion wave events, -defined here as extreme events combining energetic storm wave and high spring tide level-, and are crucial for understanding giant storm wave impacts on coastal geomorphology. Banneg Island, located off the coast of Brittany (France), faces Atlantic storm waves that are not attenuated in this highly exposed area. This island is characterised by CBD resulting from the erosion of western cliffs, that have accumulated at the top of the island as a result of storm wave/inudation processes. These accumulations have been subjected to topo-morphological survey for the last two decades (using GNSS measurements from 2005-2012, and using UAV-based measurements since 2012). Hydrodynamic conditions (wave and water levels) were also analyzed. We used these data to analyse the frequency of extreme events over the last 20 years. The results show a good relationship between boulder transport (measured as volume of boulder displacement) and the frequency of extreme events inundating the island. Over the survey period, we found significant interannual variability in the occurrence of these extreme events, depending on winter weather conditions. This storminess variability is significantly correlated with the WEPA climatic index, calculated on the 3 winter months (December to February). Finally, the results from Banneg Island were compared with long-term monitoring carried out in other sectors along the coast of Brittany, to build a comprehensive picture of storminess and its impact on coastal change in Brittany over the last 20 years
Variance of dust temperature and spectral index in Planck polarization data using spin-moment expansion
No full textInternational audienceThermal dust is the major polarized foreground hindering the detection of primordial CMB B-modes. Its signal presents a complex behavior in frequency space inherited from the joint variation in our Galaxy of the orientation of magnetic fields and of the spectral properties of dust grains aligned with magnetic field lines. In this work, we present a new framework for analyzing the thermal dust signal using polarized microwave data. We introduce residual maps, represented as complex quantities, that capture deviations of the local polarized SED from the mean complex SED averaged over the sky mask. We make simple predictions that relate the values of the statistical correlation and covariances between the residual maps to the physical properties of the emitting aligned grains. The validation or falsification of these predictions provide valuable information on the nature of the dust signal. We confront our predictions with Planck data over a 97% mask excluding the inner Galactic plane. Despite its simplicity, our model captures a significant part of the statistical properties of the data. The spectral dependence of the covariances between residual maps is, for the Sroll2 version of the data, compatible with a dust model assuming only temperature variations rather than spectral index variations, while it is incompatible with either of them for the PR4 Planck official release. Our methodology can be used to analyze future high precision polarization data and build more accurate dust models to be used by the CMB community