HAL Portal Cnam (French National Conservatory for Arts and Crafts)
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Diet, fruit and vegetables and One Health: benefits for health, environment, society and the consumer—proceedings of the 9th edition of EGEA conference
No full textInternational audiencePurpose To present the outcomes of the EGEA Conference on the state of knowledge regarding the contribution of diets rich in fruit and vegetables (FV) to human and planetary health, commonly included in the One Health concept. Methods The 9th edition of EGEA Conference (20-22 September 2023, Barcelona) provided a transversal and multidisciplinary perspective on the contribution of FV to One Health, in particular to the health of individuals, society and the planet. Nearly 150 international scientists and stakeholders discussed the current state of knowledge. These proceedings are based both on a literature review and the scientic studies presented by the speakers. Results Scientic evidence conrms the role of FV in preventing cardiovascular diseases and type 2 diabetes; more evidence is needed on the eects and mechanisms of FV in cancer prevention. FV production and consumption helps ensure territorial cohesion and provides a denser, nutrient-rich diet with less environmental impact (except water use) than other food groups, but use of synthetic pesticides in FV production remains a challenge that could be addressed with agro-ecological solutions. Various factors inuence consumer choice and behaviour towards FV consumption across the lifespan, with specic periods being more conducive to change. New research is emerging on the role of FV consumption in regulating gut microbiota and on both mental and brain health; the potential role of FV production and supply in tackling biodiversity loss and climate change; and better monitoring of FV consumption. Conclusion Sucient evidence conrms the contribution of diet rich in FV to One Health, with some emerging research on this topic. Concerted actions are required towards an increased consumption of FV and a more diversied and environmentally neutral FV production
Towards crafting modern workplaces: re-considering challenges and opportunities of hybrid working
No full textInternational audienc
L'activité comme procès de travail et rapports entre sujets-en-activité
No full textInnovation pédagogiqueAs part of a problematic that links the construction of activities and the construction of subjects-in-activity, this paper hypothesises that activity always takes place within the framework of social relationships that can be analysed using the logic of a work process. These relationships can only be understood and describedcan only be understood and described in the context of a subject-activity relationship. They are an internal construction of the activity. When these relationships are not conscious for the subjects concerned, which is often the case, we can speak of relationships-in-act. Relationships-in-act are relationships established de facto between subjects and the components of their physical and social environment.components of their physical and social environment in the course of their activity. They can be inferred from observation and analysis of ‘what subjects do with them’. They are the subject of social appreciations and discourses by subjects in terms of power relationships.S’inscrivant dans le cadre d’une problématique croisant construction des activités et construction des sujets-en-activité, le présent texte fait l’hypothèse que l’activité s’effectue toujours dans le cadre de rapports sociaux dont l’analyse peut se faire à partir de la logique d’un procès de travail. Ces rapports ne peuvent être appréhendés etdécrits que dans le cadre d’une relation d’implication sujets-activités. Ils sont une construction interne à l’activité. Quand ces rapports ne sont pas conscients pour les sujets concernés, ce qui est souvent le cas, on peut parler de rapports-en-acte. Les rapports-en-acte sont des rapports établis de fait entre les sujets et lescomposantes de leur environnement physique et social à l’occasion de leur activité. Ils sont inférables à partir de l’observation et de l’analyse de « ce que les sujets en font ». Ils font l’objet d’appréciations sociales et de discours des sujets en termes de rapports de force
Global solution of Quadratic Problems by Interval Methods and Convex Relaxations
No full textInternational audienceInterval branch-and-bound solvers provide reliable algorithms for handling non-convex optimization problems by ensuring the feasibility and the optimality of the computed solutions, i.e. independently from the floating-point rounding errors. Moreover, these solvers deal with a wide variety of mathematical operators. However, these solvers are not dedicated to quadratic optimization and do not exploit nonlinear convex relaxations in their framework. We present an interval branch-andbound method that can efficiently solve quadratic optimization problems. At each node explored by the algorithm, our solver uses a quadratic convex relaxation which is as strong as a semi-definite programming relaxation, and a variable selection strategy dedicated to quadratic problems. The interval features can then propagate efficiently this information for contracting all variable domains. We also propose to make our algorithm rigorous by certifying firstly the convexity of the objective function of our relaxation, and secondly the validity of the lower bound calculated at each node. In the non-rigorous case, our experiments show significant speedups on general integer quadratic instances, and when reliability is required, our first results show that we are able to handle medium-sized instances in a reasonable running time
Analyse des incertitudes dans le contrôle prédictif appliqué aux stations d'épuration
No full textNational audienc
: Sicherheit im Zeitalter der neuen Informations- und Kommunikationstechnologien
No full textInternational audienceDieser Artikel untersucht das Konzept der verbesserten Sicherheit im Zeitalter der neuen Informations- und Kommunikationstechnologien (NICT) und hebt die ethischen, rechtlichen und gesellschaftlichen Herausforderungen hervor, die mit ihrer Einführung verbunden sind. Verbesserte Sicherheit wird durch den Einsatz fortschrittlicher Technologien wie Videoüberwachung, Gesichtserkennung und Big Data definiert, um die menschlichen Fähigkeiten zu stärken und gleichzeitig die Abhängigkeit von menschlichen Ressourcen zu verringern.Die Studie befasst sich auch mit dem Begriff der Sousveillance, der diskreten und allgegenwärtigen Überwachung, sowie der Dataveillance, die sich auf die Auswertung digitaler Daten konzentriert, um kriminelles Verhalten vorherzusehen. Obwohl diese Technologien erhebliche Möglichkeiten in Bezug auf proaktive Sicherheit bieten, werfen sie große Bedenken hinsichtlich des Schutzes personenbezogener Daten und der Grundfreiheiten auf.Der Artikel schlägt einen ausgewogenen Ansatz vor, der sich für eine Komplementarität von Mensch und Maschine einsetzt, um die Wirksamkeit der Sicherheit zu optimieren und gleichzeitig einen strengen Rechtsrahmen zu gewährleisten, der die Rechte des Einzelnen respektiert. Informationskompetenz und Schulung werden als entscheidende Hebel identifiziert, um das Bewusstsein öffentlicher und privater Akteure für die Herausforderungen der digitalen Sicherheit zu schärfen.Abschließend lädt der Artikel zu einer kritischen Reflexion über die gesellschaftlichen Auswirkungen der erweiterten Sicherheit ein und befürwortet eine ganzheitliche Perspektive, die die technologische, menschliche und regulatorische Dimension einbezieht.This article explores the concept of enhanced security in the age of new information and communication technologies (NICT), highlighting the ethical, legal and societal challenges associated with their adoption. Enhanced security is defined by the use of advanced technologies, such as video protection, facial recognition and big data, to reinforce human capacities while reducing dependence on human resources.The study also addresses the notion of sousveillance, describing discreet and omnipresent surveillance, as well as dataveillance, which focuses on the exploitation of digital data to anticipate criminal behaviour. Although these technologies offer significant opportunities in terms of proactive security, they raise major concerns regarding the protection of personal data and fundamental freedoms.The article proposes a balanced approach, advocating human-machine complementarity to optimise security effectiveness while guaranteeing a rigorous legal framework that respects individual rights. Information literacy and training are identified as crucial levers for raising public and private actors' awareness of the challenges of digital security.In conclusion, the article invites critical reflection on the societal implications of augmented security, favouring a holistic perspective integrating the technological, human and regulatory dimensions.Este artículo explora el concepto de mayor seguridad en la era de las nuevas tecnologías de la información y la comunicación (NTIC), destacando los desafíos éticos, legales y sociales asociados a su adopción. La mayor seguridad se define por el uso de tecnologías avanzadas, como la videovigilancia, el reconocimiento facial y el big data, para reforzar las capacidades humanas y reducir la dependencia de los recursos humanos.El estudio también aborda la noción de sousveillance, que describe la vigilancia discreta y omnipresente, así como la dataveillance, que se centra en la explotación de datos digitales para anticipar el comportamiento delictivo. Aunque estas tecnologías ofrecen importantes oportunidades en términos de seguridad proactiva, plantean grandes preocupaciones en cuanto a la protección de los datos personales y las libertades fundamentales.El artículo propone un enfoque equilibrado, abogando por la complementariedad hombre-máquina para optimizar la eficacia de la seguridad, garantizando al mismo tiempo un marco jurídico riguroso que respete los derechos individuales. La alfabetización informacional y la formación se identifican como palancas cruciales para concienciar a los actores públicos y privados sobre los retos de la seguridad digital.En conclusión, el artículo invita a una reflexión crítica sobre las implicaciones sociales de la seguridad aumentada, favoreciendo una perspectiva holística que integre las dimensiones tecnológica, humana y normativa.Cet article explore le concept de sécurité augmentée à l'ère des nouvelles technologies de l'information et de la communication (NTIC), en mettant en lumière les défis éthiques, légaux et sociétaux associés à leur adoption. La sécurité augmentée se définit par l'utilisation des technologies avancées, telles que la vidéoprotection, la reconnaissance faciale et le big data, pour renforcer les capacités humaines tout en réduisant la dépendance aux effectifs humains.L'étude aborde également la notion de sousveillance, décrivant une surveillance discrète et omniprésente, ainsi que la dataveillance, axée sur l'exploitation des données numériques pour anticiper les comportements criminels. Bien que ces technologies offrent des opportunités significatives en matière de sécurité proactive, elles soulèvent des préoccupations majeures concernant la protection des données personnelles et les libertés fondamentales.L'article propose une approche équilibrée, prônant la complémentarité homme-machine pour optimiser l'efficacité sécuritaire tout en garantissant un cadre juridique rigoureux et respectueux des droits individuels. La littératie informationnelle et la formation sont identifiées comme des leviers cruciaux pour sensibiliser les acteurs publics et privés aux enjeux de la sécurité numérique.En conclusion, l'article invite à une réflexion critique sur les implications sociétales de la sécurité augmentée, en privilégiant une perspective holistique intégrant les dimensions technologiques, humaines et réglementaires
Transient rheology and morphology in sheared nanolayer polymer films
No full textInternational audienceThe rheology of coextruded layered films of polystyrene/poly(methyl methacrylate) (PS/PMMA) has been studied with small and large amplitude oscillations at a temperature above their glass transition. While the complex viscosity remains constant over the experimental time window for the micron-sized layered films, a decrease has been observed for the nanolayered films. The rheological behavior has then been correlated to the morphological evolution of the multilayer films while the nanolayers dewet. Layer breakup followed by retraction and coalescence leading to a lamellar-like blend morphology followed by a nodular-like morphology has been evidenced in the nanolayer films, for all compositions and conditions tested. The analysis of the microscopic images of the Lfilm cross-sections also provided the droplet size distribution. The nodular morphology is achieved more rapidly when the initial layers are the thinnest at low strains, while at high strains the formation of these droplets is prevented
UV-A treatment of P(VDF-TRFE-CFE): a route to efficient solid-state cooling solutions
No full textInternational audienceElectrocaloric (EC) materials are gaining significant attention as eco-friendly alternatives to traditional gas refrigerants in next-generation cooling technologies due to their outstanding caloric properties and compact design [1]. The EC effect, which is characterized by isothermal entropy change (ΔS) and adiabatic temperature change (ΔTadia) under an applied electric field, has already been demonstrated in several cooling devices [2]. Among the promising candidates, the P(VDF-TrFE-CFE) terpolymer stands out for its large ΔTadia and ease of processing into thin films via solvent casting. However, solvent-cast films typically exhibit insufficient EC responses (1.5 °C at 50 V/μm) and high dielectric losses, limiting their potential in practical applications [3].In this work, we present a straightforward post-processing method using low-energy UV-A irradiation to enhance the EC effect and minimize dielectric losses in P(VDF-TrFE-CFE) films. After irradiation, the material exhibits new functional groups, thicker crystalline lamellae, and a denser structure. X-ray diffraction under an electric field reveals the appearance of a defective ferroelectric phase alongside the ferroelectric (FE) phase, with the latter occurring at a lower electric field post-irradiation, indicating that UV-induced modifications favor the polar phase. These changes result in a significant improvement in EC performance, with an increase in ΔTadia from 1.76 °C to 2.88 °C at 60 V/μm and reduced dielectric losses.This work highlights a simple yet effective strategy to enhance the performance of P(VDF-TrFE-CFE) terpolymer films, making them more suitable for solid-state refrigeration applications
The long-term effects of grade retention: Empirical analysis on French data
No full textDocuments de travail, n°301, Aubervilliers : InedIn order to estimate the causal impact of grade retention in French lower secondary school on various long-term outcomes, we conducted a longitudinal study on the trajectories of French students who entered grade 6 in the 1995-1996 academic year over a period of 17 years. The results indicate that grade retention has a significant negative impact on both obtaining a secondary school diploma and a higher education qualification. This affected students across all socioeconomic groups, both boys and girls. However, the negative effect on wages is observed only for boys and for students from low socioeconomic backgrounds. A series of robustness checks confirm the reliability of the results
Syndicalisme, travail et politique
No full textNational audienceCan subordination really be reduced in the workplace here and now, or is this idea simply naïve and ultimately wrong if the aim is to revolutionise the social ends of production as defined by the capitalist class structure?” A “controversy” centres on this question, which was initially formulated by Yves Clot and is principally addressed to certain types of work. It allows participants to clarify their points of view, their differences and their convergences in relation to a series of theoretical and political questions associated with approaches aimed at transforming work and the current or potential role of trade union organisations in this area.La subordination peut-elle vraiment reculer dans le travail ici et maintenant ou n’est-ce là qu’une naïveté, finalement coupable si l’objectif reste de révolutionner les finalités sociales de la production définies par la structure de classes capitaliste ? ». C’est autour de cette question, posée initialement par Yves Clot, et adressée en particulier à certains travaux, que se déploie cette « controverse ». Elle permet aux participant·e·s de préciser leur point de vue, leurs divergences et leurs convergences, sur une série de questions théoriques et politiques associées aux démarches visant à transformer le travail et au rôle, actuel ou potentiel, des organisations syndicales en ce domaine