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Free-Surface Effects on Two-Dimensional Hydrofoils by RANS-VOF Simulations
No full textInternational audienc
Effet de la relaxation des contraintes sur la cristallisation induite mécaniquement dans le caoutchouc naturel
No full textInternational audienc
Hack1robo 2023 : Hackathon sur l'Intelligence Artificielle, la Robotique et les Sciences Cognitives
No full textNational audienceHack1Robo est un hackathon organisé collectivement par des membres de différentes équipes du centre Inria Bordeaux et de l'Université de Bordeaux. L’objectif de cet évènement est de proposer une action de médiation autour des axes de recherche d’Inria : IA, robotique, sciences cognitives, … de vulgariser le savoir des chercheurs / équipe et de rendre accessible la technologie.L’événement s’est déroulé du 02 au 04 juin 2023 au FabLab de Cap Sciences. Ce projet était ouvert à toutes personnes intéressées et ayant des connaissances dans les thématiques abordées par ce hackathon ou des compétences transversales pouvant être utiles à divers projets. L’édition 2023 a accueilli 27 personnes.C’est une action de médiation envers les étudiants de l’écosystème universitaire bordelais ayant pour vocation d’une part de susciter des intérêts, voir des vocations chez certains étudiants sur les thématiques concernées (IA, robotique …) d’une part ; et d’autre part de rapprocher certains étudiants ou projets prometteurs des futures activités des laboratoirs de recherche d’Inria et de l’Université de Bordeaux. Par exemple, deux des projets les plus prometteurs de l’édition de 2023 (en lien avec un EGG pour le premier et avec la bibliothèque ReservoirPy pour le second) ont été sélectionnés pour participer au hackathon Hackatech (organisé par Inria en Novembre 2023) avec l’objectif de l’emmener vers une technologie commercialisable
MISO System with Intelligent Reflecting Surface-Assisted Cellular Networks
No full textInternational audienceThis paper proposes an architecture based on Intelligent Reflecting Surfaces (IRSs) to improve the performance of future cellular networks. Specifically, we investigate the use of IRSs in combination with statistical Channel State Information (CSI) to enhance the coverage of Base Stations (BSs) in Multiple-Input Single-Output (MISO) systems. Furthermore, we exploit IRSs to reduce the complexity of the proposed architecture, and therefore the total cost, by reducing the number of required antennas at the transmitters (i.e., BSs). At first, we consider a Rayleigh fading channel between the transmitter and the receiver, and we assume the existence of a Line of Sight (LoS) between the BS and the IRS, as well as between the IRS and the destination. In the second part, we investigate the case of a Single-User Multiple-Input Single-Output (SU-MISO) system, where we study the benefits of IRSs in terms of coverage of the BS; then, we formulate a problem for a Multi-User Multiple-Input Single-Output (MU-MISO) system where the IRS is considered as a block of resources that can assist a certain number of users. The problem of managing the IRS resources is formulated as a nonlinear integer problem. We solve the optimization problem using an exhaustive search and propose two low-complexity heuristic algorithms. The performance of the system is evaluated with respect to a variable number of users, the position of the IRS, the required SNR, and the size of the cell. Simulation results corroborate the proposed approach and show that the introduction of the IRS in the network architecture enhances the overall performance of the network, extends the coverage area, enhances users’ satisfaction, and improves the SNR value, while optimizing the required number of antennas at the BS
Introduction des technologies d’intelligence artificielle dans l’innovation de défense : analyse des réseaux
No full textInternational audienc
Titanium-catalysed transformations of alkynes into complex molecular architectures
No full textInternational audienc
Analysis of Acid Diffusion Effects on Physical Properties of Polymer Composites: A Combined Study of Mechanical and Electrical Characterization
No full textInternational audienceIn this study, we examined the impact of carbon nanotube (CNT) concentration on the mechanical properties of epoxy/CNT composites under acid exposure. Samples with varying CNT concentrations (0% to 5%) were fabricated and characterized using dynamic mechanical analysis (DMA) and nanoindentation. Beyond the percolation threshold, the composites experienced decreased bulk mechanical properties due to CNT agglomeration. Acid exposure for one week and one month revealed a gradient of properties from the sample’s skin to its core. Overall, the composites exhibited modified physical properties, with degradation influenced by the CNT concentration. Higher concentrations acted as barriers but also created pathways for acid diffusion through pores surrounding CNT agglomerates. The agreement between nanoindentation and vector network analyzer (VNA) measurements further supported our findings. This convergence of mechanical and electromagnetic characterization techniques holds promise for wireless structural health monitoring (SHM) applications. Our study enhances the understanding of epoxy/CNT composites for SHM applications. The relationship between CNT concentration, acid exposure, and mechanical properties guides material selection and the development of real-time damage-detection techniques. Integrating multiple measurement techniques, as demonstrated by the agreement between nanoindentation and VNA data, provides a comprehensive understanding of structural behavior, improving SHM practices