Hal-Diderot
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The ill-posed Cauchy problem by Controllability the elliptic case
No full textInternational audienceIn this paper, we are dealing with the ill-posed Cauchy problem for an elliptic operator. To do this, we interpret the problem as an inverse problem, and therefore a controllability problem. This point of view induces a regularization method that makes it possible, on the one hand, to characterize the existence of a regular solution to the problem. On the other hand, this method makes it possible to obtain a singular optimality system for the optimal control, without resorting to any additional assumption, such as that of non-vacuity of the interior of the sets of admissibles controls, an assumption that many analysis have had to use. From this point of view, the regularization method presented here, called controllability method, is original for the analyzed problem
Frugal day-ahead forecasting of multiple local electricity loads by aggregating adaptive models
No full textWe focus on day-ahead electricity load forecasting of substations of the distribution network in France; therefore, our problem lies between the instability of a single consumption and the stability of a countrywide total demand. Moreover, we are interested in forecasting the loads of over one thousand substations; consequently, we are in the context of forecasting multiple time series. To that end, we rely on an adaptive methodology that provided excellent results at a national scale; the idea is to combine generalized additive models with state-space representations. However, the extension of this methodology to the prediction of over a thousand time series raises a computational issue. We solve it by developing a frugal variant, reducing the number of parameters estimated; we estimate the forecasting models only for a few time series and achieve transfer learning by relying on aggregation of experts. It yields a reduction of computational needs and their associated emissions. We build several variants, corresponding to different levels of parameter transfer, and we look for the best trade-off between accuracy and frugality. The selected method achieves competitive results compared to state-of-the-art individual models. Finally, we highlight the interpretability of the models, which is important for operational applications
Résultats de l’enquête Sivis 2021-2022 auprès des écoles publiques et des collèges et lycées publics et privés sous contrat
No full textChaque note d’information présente les résultats les plus récents issus des exploitations d’enquêtes et d’études statistiques. Cette publication apporte l’éclairage de la direction de l’évaluation, de la prospective et de la performance (DEPP) à la compréhension et à l’analyse du système éducatif français. Elle est disponible en ligne, sous la forme de fichiers imprimables à télécharger, accompagnés de tableaux de données chiffrées et de graphiques.Au cours de l’année scolaire 2021-2022, les chefs d’établissement du second degré des secteurs public et privé sous contrat ont déclaré en moyenne 12,3 incidents graves pour 1 000 élèves. Dans les écoles publiques, les incidents sont moins fréquents. Au cours de l’année scolaire 2021-2022, les inspecteurs de l’Éducation nationale (IEN) ont déclaré 3,0 incidents graves pour 1 000 écoliers. Aucun incident grave n’est déclaré pour huit écoles publiques sur dix et dans un établissement du second degré sur trois.La violence en milieu scolaire se manifeste principalement par des atteintes verbales aux personnes.Dans les écoles publiques, les écoliers sont impliqués comme auteurs dans 58 % des incidents graves déclarés par les IEN et les familles dans 33 % des cas. Dans le second degré, les collégiens et lycéens sont impliqués dans 93 % des incidents graves déclarés par les chefs d’établissement.Du primaire au secondaire, les garçons sont davantage impliqués que les filles dans les actes de violence, à la fois du côté des auteurs et des victimes. Entre écoliers, une violence sur trois exercée par les garçons envers les filles est à caractère sexuel ; c’est une sur quatre entre collégiens et lycéens. Enfin, les violences commises par des élèves envers des filles s’exercent plus souvent dans le cadre d’un harcèlement
From incubator’s knowledge transfer to sustainability start-ups’ impact: a case study in a French support program
No full textInternational audiencePurpose Sustainability start-ups introduce business models that address current environmental and social challenges. However, to reach their mission, they need to integrate the intention of delivering such impact since their formulation. Business incubators show promise in supporting them in this process by enhancing their access to resources and knowledge during the early stage. For these reasons, this paper aims to investigate the transfer of knowledge in a support program, outlining what knowledge is transferred in the program and through which activities for encouraging the generation of sustainability start-ups’ impact. Design/methodology/approach The present paper is supported by a qualitative case study methodology based on primary data (interviews) and secondary data (internal and external documents) related to a French support program. Findings The study shows that the support program transfers explicit and tacit knowledge for encouraging the generation of sustainability impact, throughout three main phases: awareness, identification and assessment. Research limitations/implications The limitation concerns the analysis of a French support program and the focus on sustainability start-ups. Future research lines will study other and more traditional business incubators to confirm and possibly enrich the results. Practical implications The study has managerial implications for incubator managers willing to support sustainable entrepreneurship and for sustainable entrepreneurs who want to find a support program and reach their impact. Social implications The study shows that a sustainability orientation in business incubators can play a role in fostering sustainable development through the creation of new sustainability ventures. Originality/value This paper contributes to two different fields: sustainable entrepreneurship support and knowledge management in incubators
Scientific value of the quantum tests of equivalence principle in light of Hilbert's sixth problem
No full textInternational audienceIn his sixth problem, Hilbert called for an axiomatic approach to theoretical physics with an aim to achieve precision and rigour in scientific reasoning, where logic and language (semantics) of physics play the pivotal role. It is from such a point of view, we investigate the scientific value of the modern experiments to perform quantum tests of equivalence principle. Determination of Planck constant involves the use of acceleration due to gravity of the earth (g) that results in the force on a test mass. The equivalence between inertial mass and gravitational mass of a test object is assumed in the process of logically defining g from the relevant hypotheses of physics. Consequently, if Planck constant is used as input in any experiment (or in the associated theory that founds such an experiment) that is designed to test the equivalence between inertial and gravitational mass, then it is equivalent to establish a scientific truth by implicitly assuming it i.e. a tautology. There are several notable examples which plague the frontiers of current scientific research which claim to make quantum test of equivalence principle. We question the scientific value of such experiments from Hilbert’s axiomatic point of view. This work adds to the recently reported semantic obstaclein any axiomatic attempt to put ``quantum” and ``gravity” together, albeit with an experimental tint
Memoria final del proyecto desarrollado en el marco del Programa Experimental de Formación e Innovación HERMES: desarrollo profesional docente a través de estancias formativas durante el curso 2021-22
No full textEn esta memoria se presenta la trayectoria de trabajo seguida dentro de una experiencia de colaboración docente escuela-universidad promovida por el Programa experimental de formación e innovación “Hermes”. Este proyecto, que cobra vida gracias a un convenio de colaboración entre la Dirección Provincial del Ministerio de Educación y Formación Profesional en Ceuta y la Universidad de Granada (Campus Ceuta), ha contribuido a la mejora de la práctica docente y el desarrollo profesional de las docentes implicadas en la experiencia a través de la realización de estancias formativas durante el curso académico 2021-2022. Los intercambios formativos bidireccionales se han desarrollado entre los meses de enero a mayo de 2022 y han tenido lugar entre el CEIP Ramón María del Valle Inclán y la Facultad de Educación, Economía y Tecnología de Ceuta de la Universidad de Granada. Han participado en la experiencia dos docentes del centro educativo y una profesora del área de Didáctica y Organización Escolar de la facultad. Las profesoras implicadas optaron por una propuesta de trabajo colegiado (con una vertiente de formación, de innovación y de investigación) en torno al proceso de enseñanza y aprendizaje de un tema que, en la actualidad, preocupa y ocupa la atención de muchos docentes de educación infantil, la diversidad familiar. ¿Está preparada la escuela para tratar la diversidad familiar?, ¿cuál es el tratamiento de la diversidad familiar en las aulas de infantil?, ¿qué valoración hacen los futuros docentes de educación infantil sobre la formación académica recibida en materia de diversidad familiar?, ¿sabrán cómo enfrentarse a ella pedagógicamente en sus futuras aulas? son algunos de los ejes e interrogantes claves que han marcado su ritmo de trabajo, su proceso de planificación conjunto, trabajo colaborativo, encuentros, intercambios formativos, mejoras… Todos ellos elementos protagonistas y señas de identidad de la experiencia de desarrollo profesional docente vivida, al amparo del Proyecto Hermes.En esta memoria se presenta la trayectoria de trabajo seguida dentro de una experiencia de colaboración docente escuela-universidad promovida por el Programa experimental de formación e innovación “Hermes”. Este proyecto, que cobra vida gracias a un convenio de colaboración entre la Dirección Provincial del Ministerio de Educación y Formación Profesional en Ceuta y la Universidad de Granada (Campus Ceuta), ha contribuido a la mejora de la práctica docente y el desarrollo profesional de las docentes implicadas en la experiencia a través de la realización de estancias formativas durante el curso académico 2021-2022. Los intercambios formativos bidireccionales se han desarrollado entre los meses de enero a mayo de 2022 y han tenido lugar entre el CEIP Ramón María del Valle Inclán y la Facultad de Educación, Economía y Tecnología de Ceuta de la Universidad de Granada. Han participado en la experiencia dos docentes del centro educativo y una profesora del área de Didáctica y Organización Escolar de la facultad. Las profesoras implicadas optaron por una propuesta de trabajo colegiado (con una vertiente de formación, de innovación y de investigación) en torno al proceso de enseñanza y aprendizaje de un tema que, en la actualidad, preocupa y ocupa la atención de muchos docentes de educación infantil, la diversidad familiar. ¿Está preparada la escuela para tratar la diversidad familiar?, ¿cuál es el tratamiento de la diversidad familiar en las aulas de infantil?, ¿qué valoración hacen los futuros docentes de educación infantil sobre la formación académica recibida en materia de diversidad familiar?, ¿sabrán cómo enfrentarse a ella pedagógicamente en sus futuras aulas? son algunos de los ejes e interrogantes claves que han marcado su ritmo de trabajo, su proceso de planificación conjunto, trabajo colaborativo, encuentros, intercambios formativos, mejoras… Todos ellos elementos protagonistas y señas de identidad de la experiencia de desarrollo profesional docente vivida, al amparo del Proyecto Hermes
A Chronology-Based Wave Input Reduction Technique for Simulations of Long-Term Coastal Morphological Changes: An Application to the Beach of Mastichari, Kos Island, Greece
No full textInternational audienceThe main objective of the present paper is to achieve the simulation of the long-term (e.g., annual) morphological evolution (bathymetry and shoreline) of a coastal area (Mastichari beach, Greece) due to wind-generated waves in an accurate and cost-effective way. For this purpose, wave climate schematization techniques are adopted in order to reduce the computational effort without losing or distorting the crucial information. Referring to the current practice, the wave chronology is not considered in detail in these acceleration techniques, and therefore, sea bottom and shoreline evolution are not estimated as a function of time. To fill this gap, a novel and easy-to-use chronology-based wave input reduction method is developed to produce representative wave time series of different intensities and durations. The performance of all the applied techniques in the present study is evaluated, and a comparative analysis is conducted. It is shown that the new chronology-based wave input reduction method can achieve a model run-time reduction of about 70%, while at the same time, it provides satisfactorily accurate results. In general, this research could be useful for coastal engineering studies and coastal zone monitoring, and thus, it would be a valuable tool for coastal engineers and marine scientists
Antitumoral activity of Caralluma europaea on colorectal and prostate cancer cell lines
No full textInternational audienc
Intelligence artificielle et intuition: Les algorithmes d’apprentissage profondcomme occasion de décrire l’intuition
No full textSince the years 2010, and thanks to a number of feats achieved by connectionist artificial intelligence (like AlphaGo’s victory), the notion of intuition, which had been put aside by the symbolic approach, has recovered a new legitimacy. According to their inventors, deep learning algorithms manifest intuition. In order to assess this claim, this thesis describes deep learning – its history, operating, and usage –, highlights how it simulates some human abilities (perception, induction, imagination) and provides a definition of artificial intelligence. As it pretends to materialize intelligence, and more specifically intuition and creativity, the project of artificial intelligence steps on the toes of philosophers and constrains them to reopen the question of mind genesis : would gathering the adequate material conditions be enough in order for intelligence to arise, or are there some missing « ingredients », of which intuition is the name ? Drawing on the history of philosophy, like the debate between Descartes and Leibniz about formalism, as well as discussions of contemporary thinkers (Bachelard, Bateson, Caillois, Derrida, Latour, Rosset), AI founders (McCarthy, Turing), and deep learning inventors (LeCun, Hinton), this thesis offers a description of intuition and of some features (comprehension, reflexivity, invention) that seem reluctant to simulation. Finally, it examines the notion of randomness in order to assess the possibility, for a machine, to originate new forms.Grâce aux succès techniques remportés par l’école connexionniste dans les années 2010, dont la victoire d’AlphaGo, la notion d’intuition, longtemps mise à l’écart par l’école symbolique, a repris droit de cité dans le champ de l’intelligence artificielle (IA). Selon leurs inventeurs, les algorithmes dits « d’apprentissage profond » (deep learning) font preuve d’intuition. Afin d’apprécier la pertinence de cette affirmation, cette thèse présente les réseaux de neurones d’apprentissage profond – leur histoire, leur fonctionnement, leur usage –, et s’arrête sur leur manière de simuler certaines de nos facultés (perception, induction, imagination), puis propose une définition du projet d’intelligence artificielle. En aspirant à matérialiser l’intelligence, et plus précisément l’intuition et la créativité, le projet d’intelligence artificielle s’immisce dans le champ de la philosophie et invite à rouvrir la question de la genèse de la pensée : suffit-il de réunir certaines conditions matérielles pour susciter l’intelligence, ou bien d’autres « ingrédients », dont l’intuition serait le nom, sont nécessaires ? En s’appuyant sur l’histoire de la philosophie (le différend entre Descartes et Leibniz autour de la « pensée aveugle »), sur des textes de penseurs plus contemporains (Bachelard, Bateson, Caillois, Derrida, Latour, Rosset), des fondateurs du projet d’IA (McCarthy, Turing) et de chercheurs actuels (Hinton, LeCun) cette thèse offre une description de l’intuition, de phénomènes récalcitrants à la simulation (compréhension, réflexivité, invention), et mène une réflexion sur le hasard afin de statuer sur la possibilité, pour les machines, d’être à l’origine de formes nouvelles