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SU3plus: An Enhanced Swin-UNet for Synthesizing Vertically Integrated Liquid from Multiple Meteorological Satellite Data
No full textInternational audienceRadar composite reflectivity is a crucial component of Earth observation data, playing a significant role in applications such as weather forecasting and climate disaster tracking. Due to the deployment challenges and limited coverage of meteorological radars, it is impossible to collect corresponding radar reflectivity in areas such as mountains and oceans. In such cases, using deep learning methods to reconstruct radar reflectivity from meteorological satellite data becomes an effective solution. However, Earth observation data is complex and exhibits strong long-range dependencies. Such data characteristics require the ability to model long-distance dependencies, making the Transformer more suitable for this specific data. With the ultimate goal of producing high reconstruction quality, we propose in this paper a novel architecture, designated by SU3plus, based on the Swin Transformer with a multi-scale feature fusion mechanism, while leveraging multiple channels of satellite data. Moreover, we define an appropriate loss function by combining the weighted versions of standard metrics, to take into account the data distribution imbalance and improve the reconstruction performance. Extensive experiments, carried out on the SEVIR storm dataset, confirm the effectiveness of the proposed approachcompared to several state-of-the-art models
Faut-il abandonner la résilience ?
No full textInternational audienceThis presentation addresses resilience from the perspective of a social psychologist and through the analysis of healthcare situations. The success of resilience involves two stages: the stage of individual recovery, and the stage of crisis resolution, agility, and degraded mode. In the first case, the critique is already classic: resilience risks placing the responsibility for recovery on the person who “bounces back” or not, regardless of their social conditions. In the second case, the promotion of resilience as a response to major crises leads to the trivialization of forms of degraded mode work, such as those that have become established during the COVID-19 pandemic. Between the two, a powerful social imaginary, against a backdrop of personal development, contributes to blurring the lines by making resilience desirable.Cette communication aborde la résilience à partir d'un point de vue de psychologue social et de l'analyse des situations de soin. Le succès de la résilience comporte deux temps : le temps du rebondissement individuel, le temps de la résolution des crises, de l'agilité et du mode dégradé. Dans le premier cas de figure, la critique est déjà classique : la résilience risque de faire porter sur la personne qui "rebondit" ou non, la responsabilité de sa reprise en main indépendamment de ses conditions sociales. Dans le deuxième cas de figure, l'apologie de la résilience comme réponse aux crises majeures conduit à banaliser des formes de travail en mode dégradé, telles qu'elles se sont instaurées durant la Pandémie de la Covid-19. Entre les deux, un puissant imaginaire social, sur fond de développement personnel, contribue à brouiller les cartes en rendant la résilience désirable
New Huygens Type Trigonometric and Hyperbolic Inequalities
No full textIn this paper, some Huygens type inequalities involving trigonometric and hyperbolic functions are refined and sharpened. We thus improve established inequalities and provide new ones
Questionner la posture de recherche du·de la chercheur·se lorsque son terrain se situe sur ses propres plateformes socionumériques
No full textInternational audienc
Caractérisation du fauteuil, de l'utilisateur et des déplacements pour l'optimisation numérique des réglages des fauteuils roulants manuels
No full textThe adaptation of a manual wheelchair (MWC) to its user is a complex and iterative process, requiring in-depth expertise from the clinical team and representing a physically demanding step for the patient. Numerical methods could help streamline this procedure. However, beyond the necessary numerical models, achieving individualized results requires that predictions incorporate the characteristics of the MWC, its user, and their movements. This thesis aimed to propose methods for characterizing the various parameters involved. To this end, studies were conducted to: 1) determine the configuration and inertial properties of MWCs; 2) assess the maximum torque production capacities of MWC users; and 3) measure MWC kinematics during real-world locomotion while identifying the type of locomotor action performed. Additionally, databases on MWCs and their users were initiated. Finally, as an outlook, this thesis presents a sample of numerical simulations of MWC propulsion, varying the studied characteristics. These simulations illustrate both the potential and the limitations of current numerical model implementations.L’adaptation d’un fauteuil roulant manuel (FRM) à son utilisateur est un processus complexe et itératif, nécessitant une expertise approfondie de la part de l’équipe clinique et représentant une étape physiquement exigeante pour le patient. Les méthodes numériques pourraient aider à alléger cette procédure. Toutefois, au-delà des modélisations nécessaires, l'individualisation recherchée des résultats exige que les prédictions intègrent les caractéristiques du FRM, de son utilisateur, et de leurs déplacements. Dans cette optique, cette thèse avait pour objectif de proposer des méthodes de caractérisation des différents paramètres impliqués. Pour cela, des travaux ont été menés afin de 1) déterminer la configuration et les propriétés inertielles des FRM ; 2) évaluer les capacités maximales de production de couple articulaire des utilisateurs de FRM ; et 3) mesurer la cinématique du FRM lors de déplacements réels, en identifiant le type d’action locomotrice effectuée. Par ailleurs, des bases de données ont été initiées sur les FRM et leurs utilisateurs. Enfin, en ouverture, cette thèse propose un échantillon de simulations numériques de la propulsion en FRM, en faisant varier les caractéristiques étudiées. Ces simulations illustrent à la fois les potentialités et les limites des implémentations actuelles des modèles numériques
Inertia-induced power-law scaling in martensites
No full textMartensites subjected to quasistatic deformation are known to exhibit power law distributed acoustic emission in a broad range of scales, however, the origin of the observed scaling behavior and the mechanism of self-organization towards apparent criticality remains obscure. Here we argue that the power law structure of intermittent fluctuations can be at least partially interpreted as an effect of inertia. We build on the insight that inertial dynamics, evidenced by acoustic emission, can become an important factor if the underlying mechanical system is only marginally stable. We first illustrate the possibility of inertia-induced heavy-tailed avalanche size distributions using a prototypical example of a discrete chain with bi-stable springs. We then explore the effects of inertia in fully realistic two-and three-dimensional continuum models of elastic phase transitions. In particular, we demonstrate that a three-dimensional model can produce not only qualitative but also quantitative agreement with experiment.</div
La gémellité homozygote à l’épreuve de la fin d’adolescence
No full textInternational audienceThe process of differentiation is singularly revived during adolescence as it is harnessed in the conquest of otherness, the deployment of creative capacities and the process of becoming a subject. Twinhood in adolescence doubles the difficulties of individuation in relation to Oedipal figures through an acute conflict linked to issues of separation between the twins. Here, the psychological functioning of two homozygous twin sisters in their late teens is explored. The method adopted was based on a semi-structured interview and projective tests whose clinical analysis reflect the constant struggle between undifferentiation and differentiation. The archaic and depressive recurrences identified provide grounds for hypothesizing the existence of a “unicity complex”, specific to homozygous twins, which is severely put to the test during the subjectivation process.El proceso de diferenciación se reaviva especialmente durante la adolescencia, como medio para conquistar la alteridad, desplegar las capacidades creativas y convertirse en sujeto. La gemelaridad en la adolescencia duplica la dificultad de individuación en relación con las figuras edípicas, con un conflicto agudo ligado a las cuestiones de separación entre los gemelos. Este artículo explora el funcionamiento psíquico de dos hermanas gemelas homocigóticas al final de la adolescencia. El análisis se basa en una entrevista semiestructurada y en pruebas proyectivas cuyo análisis clínico refleja la lucha constante entre la indiferenciación y la diferenciación. Las recurrencias arcaicas y depresivas identificadas sugieren la existencia de un «complejo de unicidad», específico de la gemelaridad homocigótica, que se ve sometido a una tensión particular durante el proceso de subjetivación.Le processus de différenciation est singulièrement ravivé à l’adolescence au service de la conquête de l’altérité, du déploiement des capacités créatives et du devenir sujet. La gémellité à l’adolescence dédouble la difficulté de l’individuation à l’égard des figures œdipiennes par un conflit aigu lié aux enjeux de séparation entre les jumeaux. Cet article porte sur une exploration du fonctionnement psychique de deux sœurs jumelles homozygotes en fin d’adolescence. L’analyse repose sur un entretien semi-structuré et des épreuves projectives dont l’analyse clinique traduit la lutte constante entre l’indifférenciation et la différenciation. Les récurrences archaïques et dépressives repérées permettent de supposer l’existence d’un « complexe d’unicité », propre à la gémellité homozygote, particulièrement mis sous tension à l’épreuve du processus de subjectivation
Hexagonal boron nitride thin film synthesis with a ns-pulsed MHCD: in-situ plasma diagnostics and post-growth film characterization
No full textHexagonal boron nitride (h-BN) is deposited on Si <100> wafer (≈20 cm2) via Plasma Enhanced Chemical Vapor Deposition (PECVD) using a ns-pulsed N2/Ar Micro Hollow Cathode Discharge (MHCD) as a microplasma source. For the first time, aluminum nitride (AIN) is employed as the dielectric material in the MHCD to mitigate film contamination by atomic oxygen, an issue previously observed with conventional Al 2O3 dielectrics. A comprehensive multi-diagnostic approach is followed to characterize the deposited h-BN, including Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray photoelectron microscopy (XPS). In parallel, in-situ diagnostics such as optical emission spectroscopy (OES) and intensified CCD (ICCD) imaging are used to monitor plasma properties, including emission profiles, gas temperature and discharge morphology. Raman spectra reveal the E2g phonon mode of h-BN around 1366 cm⁻¹, confirming successful synthesis. SEM imaging reveals analmost complete surface coverage by the film, with localized delamination. This is probably due to an uneven resistive heating of the Si wafer, rapid post-deposition cooling (∼13 K/min) and ambient exposure. AFM analysis indicates an average thickness of about 33 nm after 90 minutes of deposition (∼22 nm/h deposition rate). XPS measurements reveal an average B/N atomic ratio of ∼1.5 along the wafer diameter. Deviations from ideal film properties (e.g., stoichiometric unity, uniform morphology) are attributed to plasma-induced inhomogeneities (such as non-uniform species flux and temperature gradients) among other factors (e.g., ambient exposure post-deposition), which affect nitrogen and boron incorporation and localized film properties. Despite these challenges, the MHCD-driven PECVD process demonstrates strong potential for scalable h-BN synthesis, with further optimization of the reactor design, plasma conditions, and gas chemistry required to grow ideal films
