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Livret de l'atelier de programmation centré sur les envies du spectateur : Comment améliorer la découvrabilité des films documentaires grâce à leurs métadonnées?: Atelier animé dans le cadre de la Journée d'Accélération du PEPR ICCARE
No full textRésultats scientifique issu du groupe de travail MétaDoc (Métadonnées des films documentaires) 2024-2025.Ce livret présente une approche méthodologique inédite pour indexer et recommander les films documentaires à travers leurs formes (dispositifs de réalisation) plutôt que leurs sujets (thématiques abordées). Il définit d'une part une typologie de 27 formes documentaires avec des exemples de films emblématiques. Et dresse d'autre part le portrait de 6 spectateurs types (personae) dans différents contextes de visionnage. Ce matériel permet aux participants de l'atelier de penser autrement la programmation des films en prenant en considération les parcours biographiques des spectateurs, leurs contextes de visionnage, ainsi que les formes documentaires indexées au sein d'un corpus de 286 films
Demonstration of reservoir computing in a double-drum resonator through sideband pumping approach
No full textInternational audienceReservoir computing (RC) is a computational paradigm inspired by the process of information transfer between neurons in the brain. Recently, physical reservoir computing based on the nonlinear dynamics of a system has been studied in many areas of physics. Within these systems, microelectromechanical systems (MEMS) have attracted attention because they offer energy-efficient structures that can combine sensing and computing [1]. Both conventional Duffing nonlinearity [2] and stiffness modulation have been exploited for MEMS-based RC. The double-drum microelectromechanical resonator (see Fig.1 (a)) consisting of two capacitively coupled distinct drum resonators, offers unique opportunities to study phonon-cavity electromechanics in analogy to optomechanics [3]. In this work, we present our recent work on demonstrating the RC in a two-tone sideband pumping scheme. We choose one of the coupled drums as the phonon cavity, the silicon nitride drum resonator. A pump tone is applied to the cavity sideband at frequency ωp = ωSiN + ωAl [3] and the second tone probes the phonon cavity at its resonance frequency ωSiN . This sideband pumping scheme generated phonon cycling between the Al drum and the silicon nitride drum, forming a nonlinear constructive interference [3]. By masking random numbers on each input data in a time-delayed loop to form random modulations on the amplitude of the probe signal, a virtual neuron network is created in this two-tone driving scheme. To test the calculation performance, the parity benchmark is implemented through Duffing nonlinear configuration (shown in Fig.1 (b)) and also in this sideband pumping scheme, which shows promising success rates. This sideband pumping approach extends the current single-mechanical-mode-based RC to coupled mechanical modes, paving the way for MEMS array-based RC
NEW STABILITY RESULTS FOR PIEZOELECTRIC BEAMS WITH A DYNAMIC TIP LOAD: PARTIAL DAMPING AND THE INTERPLAY OF LOWER-AND HIGHER-ORDER EFFECTS
No full textThis study extends previous work ( Özer, IEEE CDC 2024) on the stabilization of piezoelectric beam systems with a dynamic tip mass, emphasizing collocated partial damping designs. Unlike earlier approaches based on noncollocated controllers and Lyapunov methods, this work investigates the performance of collocated controllers under reduced damping configurations. A distinction is made between higher order damping, associated with the strain rate, and lower-order damping, associated with the tip velocity and the accumulated electrical current at the electrodes. It is shown that higher order damping provides stronger stabilization compared to tip velocity feedback. Conditions for exponential and polynomial decay rates are identified in relation to the damping configuration and material properties. A rigorous analytical framework is introduced to characterize these decay behaviors without relying on Lyapunov techniques or spectral analysis. Numerical simulations support the theoretical findings, highlighting the essential role of the higher-order feedback mechanism in achieving exponential stability. The results offer practical insights for applications in energy harvesting, acoustic wave control, and high-precision sensing
Physical Activity and Sport to Fight Social Isolation Among Houseless People in “Northtown” (France)
No full textInternational audienceThis article examines the impacts of a physical activity program on individuals in extreme poverty and facing social isolation in a French city we called Northtown. The findings are based on an ethnographic approach conducted between 2022 and 2023: Forty‐three session observations, twelve biographical interviews, and four structured interviews were conducted. The article first identifies the mechanisms leading to social destabilization or breakdown among the participants. Their life trajectories are analyzed to understand the construction of their social isolation, highlighting the impact of life experiences and social conditions on this situation. Due to their difficult pasts, participants are anchored in the present and find bodily engagement in physical activity sessions. These moments provide temporary escape and a form of recognition but the effects are ephemeral. After the sessions, they return to their reality marked by isolation and persistent difficulties. Physical activities offer momentary security, distraction, and relief but they cannot compensate for the lasting impacts of their life experiences as they do not address the underlying issues of their isolation and distress
Enhancing pedestrian safety at track crossing: a motion analysis study
No full textInternational audienceThis study introduces motion analysis as a novel approach for evaluating pedestrian safety at Pedestrian Track Crossings (PTC), addressing limitations of traditional assessment techniques. Using markerless 3D motion analysis, we examined movement patterns of 26 healthy participants (mean age: 22.8±2.8 years) in two locomotor tasks; i) normal walking under three conditions: standard slope, textured (tactile pavements) slope, and textured slope with safety marking. ii) emergency stopping where response times were quantified. The methodology enabled non-invasive, detailed tracking of gait parameters. Compared to walking on standard slope, results revealed significant changes in movement patterns with reduced mean walking speeds from 1.26±0.20 m/s on standard slope to 1.17±0.20 m/s on textured slope (p<0.046), and 1.21±0.19 m/s (p<0.004) on textured slope with markings. Emergency stopping response times decreased, with participants halting 270 ms faster on textured surfaces compared to standard slope. Notably, while 67% of participants reported no perceived change in their walking behaviour, quantitative analysis demonstrated significant modifications in gait parameters, highlighting the unconscious influence of environmental features on pedestrian behaviour. This research demonstrates the importance of quantitative motion analysis in safety equipment assessment, overcoming the subjective nature of questionnaires and limited scope of in-situ observational studies. The findings suggest including the tactile pavements in the future passive safety equipment and establish a methodological framework for future investigations using biomechanical analysis in railway crossing safety. This cross-disciplinary approach provides unprecedented insights into human-environment interactions, paving the way for more effective safety measure design and implementation
The art and science of translucent color organic solar cells
No full textInternational audienceThe artistic and scientific perspectives of the translucent color organic solar cells (OSCs), made with the emerging narrowband nonfullerene acceptors are explored. The translucent color OSCs, comprising a Fabry–Pérot microcavity optical coupling layer, have a power conversion efficiency of >15% and a maximum transparency of >20% for the three primary colors. The performance−color relationship of the translucent color OSCs is analyzed using a combination of high-throughput optical computing and experimental optimization, allowing light with desired color to pass through, while absorbing enough light to generate electricity. Replication of Piet Mondrian’s artwork “Composition C (1920)” is demonstrated using a 10 × 10 cm2-sized translucent OSC module with a wide palette of colors and hues. The outcome of the work offers an opportunity for translucent color OSCs to function as both esthetic art and power generating windowpanes for use in our homes, offices, and even greenhouses
Deep eutectic solvent enhances antibacterial activity of a modular lytic enzyme against Acinetobacter baumannii
No full textInternational audienceAbstract In this study, we evaluated the combined effect between MLE-15, a modular lytic enzyme composed of four building blocks, and reline, a natural deep eutectic solvent. The bioinformatic analysis allowed us to determine the spatial architecture of MLE-15, whose components were bactericidal peptide cecropin A connected via a flexible linker to the cell wall binding domain (CBD) of mesophilic 201ϕ2 − 1 endolysin and catalytic domain (EAD) of highly thermostable Ph2119 endolysin. The modular enzyme showed high thermostability with the melting temperature of 93.97 ± 0.38 °C, significantly higher than their natural counterparts derived from mesophilic sources. The minimum inhibitory concentration (MIC) of MLE-15 was 100 µg/mL for a panel of Gram-positive and Gram-negative bacteria, while the MIC of reline ranged from 6.25 to 25% v/v for the same strains. The addition of reline effectively reduced the MIC of MLE-15 from 100 µg/mL to 3.15–50 µg/mL. This combination displayed additive effects for most strains and synergism for extensively antibiotic-resistant Acinetobacter baumannii and Bacillus subtilis . The subsequent evaluation revealed that MLE-15 eliminated planktonic cells of A. baumannii RUH134, but was ineffective against matured biofilms. However, combined with reline, MLE-15 reduced the bacterial load in the matured biofilm by 1.39 log units. Confocal fluorescence microscopy indicated that reline damaged the structure of the biofilm, allowing MLE-15 to penetrate it. Additionally, MLE-15 and its combination with reline eradicated meropenem-persistent cells of A. baumannii RUH134. Effectiveness in lowering the MIC value of MLE-15 as well as protection against antibiotic-tolerant persister cells, indicate that MLE-15 and reline combination is a promising candidate for effective therapies in bacterial infections, which is especially important in the light of the global crisis of antimicrobial resistance
Nanoscale Calibration Standards for On-Wafer S-Parameters measurements up to 110 GHz
No full textInternational audienceWe report the first experimental results on the design and fabrication of nanoscale on-wafer calibration standards operating up to 110 GHz. The propagation constant and effective permittivity of coplanar waveguide (CPW) transmission lines (TLs) are extracted from raw S-parameters using the Thru-Reflect-Line (TRL) method. Experimental data show deviations in extracted propagation characteristics when comparing nanostructures to microscale structures.</div
Misbehavior Detection in Connected Vehicle: Pre-Bayesian Majority Game Framework
No full textInternational audienceEphemeral networks, such as vehicular ad hoc networks, face significant security challenges due to their transient nature and susceptibility to malicious nodes. Traditional trust mechanisms often struggle with dynamic topologies and short-lived interactions, particularly when adversarial nodes spread misinformation. This paper proposes a dual-game theoretical framework combining pre-Bayesian belief updates with majority voting to enhance collaborative misbehavior detection in decentralized vehicular networks. The approach models node interactions through two sequential games: a pre-Bayesian game where nodes assess information credibility based on individual beliefs, followed by a majority game that aggregates collective decisions to refine trust evaluations. Simulations across scenarios with varying malicious node proportions demonstrate the framework's adaptability, showing consistent belief convergence toward accurate classifications despite increased adversarial influence. Results indicate robust performance even when 40% of nodes exhibit malicious behavior, though convergence delays highlight challenges in highly adversarial environments. The study underscores the importance of maintaining benign node majorities for system stability and suggests future integrations with machine learning for scalability. This work provides a foundation for secure, real-time decision-making in applications requiring reliable ephemeral networks, such as connected vehicle systems. nodes can manipulate data, disseminate false information, or disrupt communication, thereby compromising network performance. For example, in VANETs, a malicious vehicle might inject false traffic information, causing significant disruptions or even accidents, a</div
Analyse de la décorrélation geste-son dans la pratique de la batterie électronique
No full textInternational audienceDrumming belongs to a family of musical instruments whose practice, whether as an amateur or at a high level, is associated with an increased risk of musculoskeletal disorders (MSD), particularly of the upper limbs and lumbar spine. The vast majority of drummers learn to play on acoustic instruments, the sound intensity of which is proportional to the striking force developed. This correlation is disrupted when playing the electronic version of the instrument, which is often purchased by musicians seeking to reduce the sound produced (e.g. playing in apartments). The aim of this study was therefore to analyze whether drumming on electronic equipment would lead to a change in the kinematics and feel of drummers. To this end, several drummers were recruited to perform repeated rhythms at different pitches on acoustic and electric drums under two sound conditions (sound on and sound off with noise-canceling headphones). The sound produced and the kinematics of the upper limbs were measured by video motion capture during the beats. In addition, self-confrontation interviews were conducted after each condition. The drummers, confronted with video recordings of their actions, were asked to describe, explain and comment step by step on their performance. These interviews were also used to assess their ability to maintain a constant strike force. A questionnaire was used to obtain subjective information on how they felt. The results showed a lower sound power of electronic drums, despite a similar striking speed. This gesture-sound decorrelation could explain the increase in MSD among drummers when switching from an acoustic to an electronic instrument.La batterie appartient à la famille d'instruments de musique dont la pratique, en amateur ou à haut niveau, est associée à un risque accru de troubles musculosquelettiques (TMS) particulièrement pour les membres supérieurs et le rachis lombaire. L'apprentissage de la batterie se fait en grande majorité sur des instruments acoustiques dont l'intensité sonore est proportionnelle à la force de frappe développée. Cette corrélation se retrouve perturbée lors de la pratique de la version électronique de l'instrument qui est souvent acheté par les musiciens cherchant à réduire le son produit (ex : jeu en appartement). L'objectif de cette étude est donc d'analyser si la pratique de batterie sur du matériel électronique entraînerait un changement dans la cinématique et le ressenti des batteurs. Dans ce but, plusieurs batteurs ont été recrutés pour réaliser des rythmes répétés à différentes nuances sur batterie acoustique et batterie électrique avec deux conditions sonores (son allumé et son éteint avec casque anti-bruit). Le son produit ainsi que la cinématique des membres supérieures ont été mesurés par capture du mouvement vidéo lors des frappes. Par ailleurs, des entretiens d'auto-confrontation ont été réalisés après chaque condition. Les batteurs, confrontés à des enregistrements vidéo de leurs actions, devaient décrire, expliquer et commenter pas à pas leur performance. Ces entretiens ont également servi à évaluer leur aptitude à maintenir une force de frappe constante. Un questionnaire a permis d'obtenir des informations subjectives sur leur ressenti. Les résultats ont montré une puissance sonore inférieure de la batterie électronique malgré une vitesse de frappe similaire, cette décorrélation geste-son pourrait expliquer l'augmentation des TMS chez les batteurs lors du changement d'un instrument acoustique à électronique