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Quel avenir pour les gestes professionnels des artisans et opérateurs face à la robotique ?: Les robots collaboratifs, dotés de couches d’intelligence artificielle, pourraient accompagner artisans et opérateurs dans leurs gestes professionnels.
No full texthttps://theconversation.com/quel-avenir-pour-les-gestes-professionnels-des-artisans-et-operateurs-face-a-la-robotique-25597
Size and Thickness Effects on the Ductile Fracture Toughness of a 316 L(N) Austenitic Stainless Steel in As‐Received and Aged Conditions
No full textInternational audienceABSTRACT Measuring ductile fracture toughness for materials requires the specimen size to be large enough for the tests to be valid. The presented work investigates the size related fracture behavior of as‐received and aged 316 L(N) stainless steel through an experimental approach. It focuses on the effects of the thickness and size of the specimens on the evaluated toughness. Compact tension (CT) specimens (thicknesses from 4 to 50 mm) and double edge notched tensile (DENT) specimens (thicknesses from 2 to 5 mm) were used. At as‐received state, CT tests lead to a nonmonotonic evolution of fracture toughness with a maximum at a critical thickness. At aged state, there is no significant thickness effect as all tests are valid. The essential work of fracture measured with DENT specimens appears to be equivalent to and consequently extends the nonmonotonic evolution of the fracture toughness at small thicknesses
Intrahour solar radiation forecasting based on sun visibility for different cloud types
No full textInternational audienc
Concilier artisanat et croissance industrielle : les dispositifs de pilotage de la singularité de création dans le luxe artisanal
No full textInternational audienceCet article explore la tension entre le positionnement marketing centré sur l’artisanat et les impératifs de performance associés à la croissance industrielle dans le secteur du luxe. Il étudie plus spécifiquement l’impact des rationalisations opérées sur le processus de création dans un contexte de recrutement massif de cadres issus de la R&D et de l’innovation d’autres industries. En se basant sur une étude de cas longitudinale de 14 mois réalisée sur une maison de luxe artisanal, l’article montre que les acteurs du processus de création ont établi des dispositifs permettant d’hybrider les logiques de performances, adapté les dispositifs issus des ingénieries au positionnement centré sur l’artisanat, et créé des nouveaux dispositifs capitalisant sur le patrimoine de la maison, engageant ainsi les acteurs de la création sur une « rationalisation de la singularité » des créations de la maison tout en intégrant les enjeux de croissance industrielle
Integration of clinical, pathological, radiological, and transcriptomic data improves prediction for first-line immunotherapy outcome in metastatic non-small cell lung cancer
No full textInternational audienceAbstract Immunotherapy is improving the survival of patients with metastatic non-small cell lung cancer (NSCLC), yet reliable biomarkers are needed to identify responders prospectively and optimize patient care. In this study, we explore the benefits of multimodal approaches to predict immunotherapy outcome using multiple machine learning algorithms and integration strategies. We analyze baseline multimodal data from a cohort of 317 metastatic NSCLC patients treated with first-line immunotherapy, including positron emission tomography images, digitized pathological slides, bulk transcriptomic profiles, and clinical information. Testing multiple integration strategies, most of them yield multimodal models surpassing both the best unimodal models and established univariate biomarkers, such as PD-L1 expression. Additionally, several multimodal combinations demonstrate improved patient risk stratification compared to models built with routine clinical features only. Our study thus provides evidence of the superiority of multimodal over unimodal approaches, advocating for the collection of large multimodal NSCLC datasets to develop and validate robust and powerful immunotherapy biomarkers
Learning Data-Driven Uncertainty Set Partitions for Robust and Adaptive Energy Forecasting with Missing Data
No full textShort-term forecasting models typically assume the availability of input data (features) when they are deployed and in use. However, equipment failures, disruptions, cyberattacks, may lead to missing features when such models are used operationally, which could negatively affect forecast accuracy, and result in suboptimal operational decisions. In this paper, we use adaptive robust optimization and adversarial machine learning to develop forecasting models that seamlessly handle missing data operationally. We propose linear-and neural networkbased forecasting models with parameters that adapt to available features, combining linear adaptation with a novel algorithm for learning data-driven uncertainty set partitions. The proposed adaptive models do not rely on identifying historical missing data patterns and are suitable for real-time operations under stringent time constraints. Extensive numerical experiments on short-term wind power forecasting considering horizons from 15 minutes to 4 hours ahead illustrate that our proposed adaptive models are on par with imputation when data are missing for very short periods (e.g., when only the latest measurement is missing) whereas they significantly outperform imputation when data are missing for longer periods. We further provide insights by showcasing how linear adaptation and data-driven partitions (even with a few subsets) approach the performance of the optimal, yet impractical, method of retraining for every possible realization of missing data
Characterization of argon recoils at the keV scale with ReD and ReD+
No full textInternational audienceThe ReD experiment measured the ionization yield Qy of argon for nuclear recoils in the 2-10 keV range using a dual-phase Time Projection Chamber irradiated with neutrons from a Cf-252 fission source. The measurement extends coverage below 7 keV, confirms consistency with previous data above 7 keV, and indicates a higher Qy at lower energies. These results are relevant for argon-based experiments searching for dark matter in the form of low-mass Weakly Interacting Massive Particles, which are very sensitive to the modeling of the detector response in this energy range
Structurer la gouvernance interne à l'hôpital public
No full textThis thesis analyzes the internal governance of French public hospitals, focusing on activity clusters (pôles d’activité) andtheir ability to foster an interaction between two often conflicting logics in the hospital environment: the medical logic (Cure)and the managerial logic (Control). It traces the historical development of hospital governance in France, marked by reforms,including the introduction of activity clusters in 2005 as part of the nouvelle gouvernance hospitalière and their revision underthe Rist law in 2021, which restored the central significance of hospital services. These transformations raise questions aboutthe role of these intermediate entities (activity clusters) in the management of hospital activity. The research mobilizes severaltheoretical frameworks from management sciences and organizational theory, including the works of Henry Mintzberg onorganizational structure and hospital dynamics, as well as approaches in organizational design (Dalmasso and Sardas 2018),models of public action (new public management and new public governance) (Osborne 2010; Gand 2023), co-leadership(Gibeau et al. 2020) and network management (Klijn and Koppenjan 2016). It is based on a research-intervention carried outat Assistance Publique-Hôpitaux de Paris (AP-HP), focusing on the experience of the Départements Médico-Universitaires(DMU), introduced at AP-HP in 2019. This qualitative approach guided the development of a case study based on multipleinterviews, both participant and non-participant observations, and documentary analysis.The results show that the way DMUs operate is strongly influenced by their geographical and disciplinary design. Theconstraints placed on these entities prevent them from functioning as truly autonomous bodies responsible for their economicoutcomes. Despite these aspects, some DMUs manage to build a “community of Cure”, fostering cooperation between medicalservices through federating projects and shared norms that reinforce trust among actors. The organization of these communitiesalso favors a specific form of articulation between medical and administrative managers (“management consulting”). Finally,three types of intervention by these entities in hospital activity are identified: the intersection of activity, desired integration,and constrained integration of activity. They illustrate how the logics of Cure and Control are effectively articulated duringdecision-making processes related to hospital activity and its prospects, as well as involving forms of interdependence andtransversality between actors with a high degree of autonomy – namely the chefs de service. The thesis proposes ways toreconsider the evaluation and the role of management tools available to activity clusters, with a focus on instruments that alignwith their true purpose: building communities of Cure and coordinating interservice processes. It highlights the centralimportance of services in contemporary hospital activity, as well as the specific functions of chefs de service and chefs de pôle in hospital governance.Cette thèse analyse la gouvernance interne des hôpitaux publics français, en mettant l’accent sur le fonctionnement des pôlesd’activité et sur leur capacité à promouvoir l’articulation entre deux logiques souvent opposées dans le milieu hospitalier : lalogique médicale (Cure) et la logique managériale (Control). Elle retrace l’évolution historique de la gouvernance hospitalièreen France, jalonnée par des réformes, avec l’introduction des pôles d’activité en 2005 dans le cadre de la nouvelle gouvernancehospitalière et leur révision avec la loi Rist en 2021, qui reconnait la place centrale des services hospitaliers. Cestransformations soulèvent des interrogations sur le rôle et le fonctionnement de ces entités intermédiaires (les pôles d’activité)dans la gestion de l’activité hospitalière. La recherche mobilise plusieurs cadres théoriques issus des sciences de gestion et desthéories des organisations, comme les travaux d’Henry Mintzberg sur la structure des organisations et sur le fonctionnementhospitalier, ainsi que des approches en design organisationnel (Dalmasso et Sardas 2018), en modèles d’action publique (newpublic management et nouvelle gouvernance publique) (Osborne 2010; Gand 2023), en co-gestion (Gibeau et al. 2020) et enmanagement des réseaux (Klijn et Koppenjan 2016). Elle s’appuie sur une recherche-intervention menée au sein del’Assistance Publique-Hôpitaux de Paris (AP-HP), focalisée sur l’expérience de restructuration des pôles en DépartementsMédico-Universitaires (DMU), introduite à l’AP-HP depuis 2019. Cette approche qualitative oriente la réalisation d’une étudede cas construite à partir de nombreux entretiens, d’observations participantes et non participantes, ainsi que d’analysedocumentaire.Les résultats montrent que le fonctionnement des DMU est fortement influencé par leur composition géographique etdisciplinaire. Les contraintes auxquelles ces entités sont soumises les empêchent de fonctionner comme des entitésvéritablement autonomes et responsables de leurs résultats économiques. Malgré ces aspects, certains DMU parviennent àconstruire une « communauté de Cure », favorisant la coopération entre les services par des projets fédérateurs et des normespartagées qui renforcent la confiance entre les acteurs. L’organisation de ces communautés favorise également une formed’articulation spécifique entre directeurs médicaux et administratifs (le « management consulting »). Enfin, trois typesd’intervention des DMU sur l’activité hospitalière sont identifiés : l’intersection de l’activité, l’intégration souhaitée, etl’intégration contrainte de l’activité. Ils illustrent comment les logiques du Cure et du Control s’articulent concrètement aucours des processus de décision portant sur l’activité hospitalière et sa prospective, et impliquant des formes d’interdépendanceet de transversalité entre des acteurs dotés d’une forte autonomie, en l’occurrence les chefs de service. La thèse propose despistes pour reconsidérer l’évaluation et le rôle des outils de gestion à disposition des pôles, en privilégiant des dispositifsadaptés à leur rôle réel : la construction de communautés de Cure et la coordination des processus interservices. Elle met enlumière l’importance centrale des services dans le fonctionnement de l’activité hospitalière actuelle, ainsi que les fonctions spécifiques des chefs de service et des chefs de pôle dans la gouvernance à l’hôpital
Upcycling of cardboard into highly porous materials
No full textInternational audiencePaper and cardboard comprise about 20% of municipal solid waste [1]. Although recycling is a viable solution, its effectiveness is constrained by cellulose fiber degradation, which limits reuse to only three to five cycles before virgin fibers are required to maintain material quality [2]. This highlights the necessity for innovative methods to upcycle these materials into high-value products, such as bio-aerogels. Cellulose-based bio-aerogels possess remarkable properties, including high porosity (>90%), open-pore nanostructures, specific surface areas of 200–400 m²/g, and low density (0.05–0.2 g/cm³). These characteristics render them highly suitable for a broad spectrum of applications, including thermal insulation, catalysis, drug delivery, electrochemical processes, adsorption, separation, and the food industry [3]. Aerogel production involves drying a gel while preserving its porous structure, with the drying process defining the final properties [4]. Additionally, carbonization under a protective atmosphere can further enhance functionality, yielding carbon aerogels with expanded applications.This study explores the conversion of cellulose fibers obtained from paper and cardboard into bio-aerogels and carbon aerogels, with a focus on evaluating the influence of different drying techniques - supercritical CO₂ and evaporative low vacuum drying - on material structural and functional properties. Microcrystalline cellulose was used as a reference and pulp fibers were dissolved in an 8% NaOH-water solution, with supercritical CO₂ drying incorporating a recycling loop to enhance sustainability. Subsequent carbonization was employed to produce carbon aerogels. The research systematically analyzed the effects of drying methods and carbonization on key properties such as density, specific surface area, and morphology. The findings aim to optimize production processes and enhance aerogel performance for diverse industrial applications.Acknowledgements: The authors are grateful to the Occitanie Region and ANR (PEPR "Recyclage, recyclabilité, ré-utilisation des matières" and “Investissements d’Avenir” program, ANR-18-EURE-0021 project) for funding.References:[1]“What a Waste 2.0: A Global Snapshot of Solid Waste Management to 2050,” Sep. 2018, doi: 10.1596/978-1-4648-1329-0.[2]N. J. Schenk, H. C. Moll, and J. Potting, “The Nonlinear Relationship between Paper Recycling and Primary Pulp Requirements: Modeling Paper Production and Recycling in Europe,” J. Ind. Ecol., vol. 8, no. 3, pp. 141–162, Jul. 2004, doi: 10.1162/1088198042442379.[3]T. Budtova, “Cellulose II aerogels: a review,” Cellulose, vol. 26, no. 1, pp. 81–121, Jan. 2019, doi: 10.1007/s10570-018-2189-1.[4]S. Zhao, W. J. Malfait, N. Guerrero‐Alburquerque, M. M. Koebel, and G. Nyström, “Biopolymer Aerogels and Foams: Chemistry, Properties, and Applications,” Angew. Chem. Int. Ed., vol. 57, no. 26, pp. 7580–7608, Jun. 2018, doi: 10.1002/anie.201709014
Developing pectin aerogels with alternative drying methods for scalable production
No full textInternational audienceAerogels are solid materials with nanometer-scale pores showing interesting properties (e.g., high porosity, low density, and high specific surface area) for a range of applications. The field of aerogels based on natural resources, such as polysaccharides, is gaining more and more attention due to the need for sustainable alternatives to conventional, non-renewable counterparts. Among bio-based aerogels, pectin aerogels possess a density of around 0.1 g cm -3 and a very fine network with meso-and small macropores.[1] The preparation of pectin aerogels includes the final step of drying of the pectin wet gels with supercritical CO2, which is essential to preserve the nanostructured open porous network of the gel in the solid dry pectin aerogel. However, this step requires a specific high-pressure process and acts as a significant impediment to the industrialization of such materials. Freeze drying can be utilized as an alternative drying technique, but it typically results in materials with big macropores. [2] In this work, neat pectin aerogel-like materials were obtained after treatment in alkaline media and dry materials were obtained without the use of supercritical drying or freeze drying and without collapse of the open porous network. The influence of the pectin degree of esterification and the concentration and nature of the base used were studied. The pectin porous materials obtained have low densities, in range of 0.07 -0.30 g cm -3 and specific surface area up to 280 m 2 g -1 , similar to the analogous pectin aerogels dried with supercritical drying