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Reporting de durabilité et Notation extra-financière (ESG) : problématiques et enjeux contemporains. Normes de durabilité et audit ESG
No full textInternational audienceLa présentation sera centrée sur l’ouvrage collectif que le GT envisage de publier. Les quatre coordinateurs de l’ouvrage présentent et discutent un ensemble de problématiques concernant la normalisation ESG, la connectivité des données financières et extra-financières, l’audit des données ESG, l’intégration des critères ESG dans le contrôle de gestion et les agences de notation extra-financière
A Hierarchical Adaptive Observer Approach for Synchronization in Heterogeneous Multi-Agent Systems
No full textInternational audienceThis paper presents a novel observer-based synchronization framework designed for heterogeneous multi-agent systems operating under realistic conditions, such as discrete and noisy measurements, intermittent communication, and agent heterogeneity. The framework incorporates a hierarchical structure: a Filtered High-Gain Observer to reconstruct the leader's state in the presence of noisy and discrete measurements, a Distributed Observer which enables each follower to independently estimate the state of the leader for synchronization purposes, and a Adaptive Local Observer for each follower that simultaneously estimates its own states and unknown parameters. The local observer incorporates a closed-loop output predictor to address challenges arising from discrete measurements and ensure continuous estimation. Stability and robustness are shown using a Lyapunov-based approach, and simulation results validate the effectiveness of the proposed method to maintain precise coordination between vehicles. This approach improves performance, making it suitable for real-time vehicle platooning applications
Quelle vision organisante de l’IA Générative pour la Supply Chain ?
No full textInternational audienceCet article explore la « vision organisante » de l’intelligence artificielle générative (IA Générative) dans le domaine de la gestion de la chaîne logistique. À travers l’analyse de 42 témoignages d’experts, de fournisseurs de solutions et d’utilisateurs de l’IA Générative dans la Supply Chain, l’étude révèle les représentations des acteurs de la chaîne logistique sur les innovations liées à l’IA Générative dans la Supply Chain. L’IA Générative est perçue comme un outil d’aide à la décision, un levier d’efficacité pour la chaîne logistique et ses acteurs, et un moyen permettant de s’ouvrir à plus de réflexion et de créativité pour ces acteurs. Enfin, l’article propose des perspectives de recherche visant à approfondir la compréhension des facteurs favorisant ou freinant l’adoption de l’IA Générative dans la gestion de la chaîne logistique
Feedback multisensoriels pour la manipulation d'objets virtuels en réalité augmentée
No full textWhen we manipulate the objects around us, we use all five senses: sight, hearing, touch, taste and smell. In augmented reality, we can be confronted with purely virtual objects, artificially stimulating sight and hearing, but not, by default, stimulating the other three senses. These shortcomings in the way the user perceives the virtual objects around him make it difficult to manipulate them, so it is necessary to ensure that all five senses are correctly stimulated. Feedback is the act of sending a stimulus back to the organism once it has acted on its environment. Understanding how feedback works enables the user's senses to be correctly stimulated, thus making manipulation simpler. In the course of this thesis, we therefore set up a feedback model, enabling us to better understand the different elements that make up feedback, and to create feedbacks that meet our needs. We then used our model to develop various prototypes designed to convey the haptic properties of manipulated objects. We further developed two of these prototypes within the framework of experimental protocols. The first was designed to verify the impact of hand representation on manipulation. The second aims to study whether it is possible to induce a sensation of weight on a virtual object.Lorsque l'être humain manipule les objets qui l'entourent, il sollicite les cinq sens que sont la vue, l'ouïe, le toucher, le goût et l'odorat. En réalité augmentée, il peut être confronté à des objets purement virtuels, pouvant stimuler artificiellement la vue et l'ouïe, et ne pouvant pas, par défaut, stimuler les trois autres sens. Ces lacunes dans la façon qu'à l'utilisateur de percevoir les objets virtuels qui l'entourent rendent la manipulation de ceux-ci difficile, il est donc nécessaire de s'assurer que les cinq sens soient correctement stimulés. On appelle feedback le fait de renvoyer un stimuli à l'organisme une fois que celui-ci a agi sur son environnement. Comprendre le fonctionnement du feedback permet de stimuler correctement les sens de l'utilisateur, et ainsi de permettre de rendre la manipulation plus simple. Nous avons donc au cours de cette thèse mis en place un modèle du feedback, permettant de mieux comprendre les différents éléments qui le composent, ainsi que de créer des feedbacks répondant à nos besoins. Nous avons ensuite utilisé notre modèle pour développer différents prototypes ayant pour but de transmettre notamment les propriétés haptiques des objets manipulés. Nous avons approfondi deux de ces prototypes dans le cadre de protocoles expérimentaux. Le premier pour but de vérifier l'impact de la représentation de la main sur la manipulation. Le second a pour but d'étudier si il est possible d'induire une sensation de poids sur un objet virtuel
L’émergence et l’impact de la norme européenne GSM de téléphonie mobile
No full textInternational audienceI. Le succès mondial de la norme GSMII. Des innovations dans la gouvernance de la normeA. Le processus du développement de la norme GSM : un processus décisionnel accéléré dans un paysage institutionnel élargiB. La gestion de la propriété intellectuelle dans la gouvernance de la normalisation GSMII. Des innovations économiques et commercialesA. Au Royaume-Uni1. La libéralisation du marché des télécommunications mobiles2. Les avancées commerciales : le forfait et le subventionnement du terminalB. En France1. Un démarrage timide de la téléphonie mobile2. Le développement des services GSM favorisé par la concurrence entre trois opérateursConclusion : la réussite du GSM est à la fois technologique, politique et commercial
Document complémentaire à l'article "Étude de comparaisons de procédures de sélection de variables en régression linéaire gaussienne de grande dimension".
No full text51 pages, 50 figuresDonnées supplémentaires pour un preprintThis supplementary file is an appendix of the work entitled "Comparison study of variable selection procedures in high-dimensional Gaussian linear regression". This file contains additional graphics summarizing the behavior of the variable selection methods applied on different datasets considered in the main document
An Unexplored Diversity for Adaptation of Germination to High Temperatures in <i>Brassica</i> Species
No full textData Availability Statement: The short-read resequencing data that support the findings are available in NCBI's sequence read archive (SRA) under the project PRJNA1174687. The genetic files (bed, bim, fam) and the raw phenotype dataset is freely available at: “Tiret, Mathieu, 2025, Replication Data for: An unexplored diversity for adaptation of germination to high temperatures in Brassica species, https://doi.org/10.57745/RIOMJ8.” Seeds of the accessions are available at the following Genetic Resource Centers: BrACySol for French accessions, de Los Campos seed genebank (ESP003) for Spanish accessions, and Agricultural Institute of Slovenia for Slovenian accessions. The unique accession numbers are detailed in Table S3. For inquiries regarding Algerian, Italian, and Tunisian accessions, please refer to the contact specified in Table S3.International audienceElevated temperatures inhibit the germination of a concerning number of crop species. One strategy to mitigate the impact of warming temperatures is to identify and introgress adaptive genes into elite germplasm. Diversity must be sought in wild populations, coupled with an understanding of the complex pattern of adaptation across a broad range of landscapes. By investigating the landraces, wild, and feral populations of Algeria, Italy, France, Slovenia, Spain, and Tunisia, we assessed the response of germination to temperature increase in an unexplored diversity of 117 accessions of Brassica rapa and 66 of Brassica oleracea. Our results show that both species exhibit heat tolerance to the temperature range tested, especially B. rapa, with an increase in speed and uniformity of germination time, as well as an increase in germination rate as temperature increased. As for B. oleracea accessions, the ability to germinate under heat conditions depended on the geographical origin; in particular, southern populations showed a higher germination rate than northern populations, possibly in relation to their warmer climates of origin. These findings highlight the complex interplay between domestication, feralization, and current agronomic practices in shaping germination characteristics in Brassica species
Dynamic structural adaptation for building viable supply chains under super disruption events
No full textInternational audienceSupply chain (SC) has been increasingly challenged by disruption events (DEs), where super DEs (SDEs) comprising a sequence of DEs, e.g., COVID-19, pose significant threats with long-term impacts. To hedge against SDEs, SC viability has been introduced, whose distinctive feature is the ability to adapt the SC structure. Building SC viability via dynamic SC structural adaptation under SDEs, however, has not been quantitatively addressed in the literature. This study investigates a novel viable SC building problem under SDEs. It consists of timely assessing the disruption risk and dynamically adapting the SC structure, to satisfy uncertain demands. The aim is to find the best balance between the disruption risk and the SC operational cost. To portray the structural and temporal risk propagations along the dynamic SC structure, a new structure-variable dynamic Bayesian network (SVDBN) is proposed. Then, a bi-objective mixed-integer non-linear programming (MI-NLP) model is established. Based on analyses of problem features, a decomposition-and-clustering (DC) heuristic algorithm is designed to solve the problem. Numerical experiments are conducted to evaluate the performance of the approach, and managerial insights are provided as well
Mentor-Guided Learning in Immersive Virtual Environments: The Impact of Visual and Haptic Feedback on Skill Acquisition
No full textInternational audienceIn the early stages of learning a technical skill, trainees require guidance from a mentor through augmented feedbackto develop higher expertise. However, the impact of such feedback and the different modalities used to communicate it remainunderexplored in immersive virtual environments (IVE). This paper presents a study in which 27 participants were divided into threegroups to learn a tool manipulation trajectory in an IVE. Two experimental groups received guidance from an expert using visualand/or haptic augmented feedback, while the control group received no feedback. The results indicate that both experimental groupsshowed significantly greater improvement in tool trajectory performance than the control group from pre- to post-test, with no significantdifferences between them. Analysis of their learning curves revealed similar performance improvements in tool trajectory acrosstrials, outperforming the control group. Additionally, the visual-haptic feedback condition was linked to lower task load in three outof six dimensions of the NASA-TLX and a higher perceived interdependence with the expert's actions. These findings suggest thataugmented feedback from an expert enhances the learning of tool manipulation skills. Although adding haptic feedback did not lead tobetter learning outcomes compared to visual feedback alone, it did enhance the overall user experience. These results offer valuableinsights for designing IVEs that support mentor-trainee interactions through augmented feedback
Lecture Notes on Biodiversity
No full textInternational audienceThese lecture notes are part of the Handbook of Sustainable Finance. They provide the basics of biodiversity for students and professionals who want to understand this topic and the key challenges of biodiversity investing. The first three sections cover the definition of biodiversity, ecosystem functions and services, and threats to biodiversity. These correspond to material typically taught in conservation biology courses. The fourth section focuses on measuring biodiversity. Finally, the last two sections cover biodiversity governance and regulation, and biodiversity investment approaches.In these lecture notes, we will learn that biodiversity goes far beyond the issues of species extinction and deforestation. In fact, it is much broader and includes fisheries, food security, health issues, invasive species, natural resources, pollution, and water stress, among others. However, most measures of biodiversity focus primarily on species richness, abundance, or extinction. From a financial perspective, this is unsatisfactory, and biodiversity finance requires more sophisticated metrics. In addition, new regulations and frameworks are pushing investors to become actively involved in biodiversity restoration. The concept of double materiality also underscores the importance of biodiversity to companies and implies some hidden risks in financial assets because they impact or can be impacted by biodiversity loss. Despite growing awareness, long-term investors are not yet fully equipped to integrate biodiversity risks into their investment decisions. While progress is being made, there is still a long way to go in developing robust methodologies that can effectively integrate biodiversity into sustainable investment strategies