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Expérience de tourisme créatif et pratiques durables : Analyse exploratoire des facteurs façonnant la qualité perçue
No full textInternational audienceAlors que la recherche sur le tourisme créatif s’est principalement concentrée sur ses dimensions motivationnelles, émotionnelles et culturelles, peu d’études ont examiné les mécanismes expérientiels par lesquels la durabilité façonne la qualité perçue de l’expérience. Cette étude adopte une approche où le touriste est envisagé comme un acteur actif de son parcours, et interroge l’influence des pratiques durables sur la construction de cette qualité. S’appuyant sur une méthodologie qualitative exploratoire, elle combine l’observation de sept ateliers créatifs et la conduite de quinze entretiens sur cinq mois. Les résultats montrent que le respect de l’environnement, la transmission des savoir-faire locaux et les retombées positives pour les communautés d’accueil constituent des leviers clés dans la création d’expériences touristiques significatives, éthiques et mémorables. En éclairant les interactions entre durabilité, créativité et qualité expérientielle, cette recherche propose également des pistes opérationnelles pour concevoir des offres alignées avec les Objectifs de Développement Durable
Development of Sustainable Rubber Composites Reinforced with Silk Fabric for High-Performance Bicycle Tires: Material Characterization and Prototype Testing
No full textInternational audienceNatural rubber (NR) composites reinforced with fabrics were prepared through compression molding by sandwiching a layer of fabric between two layers of NR. A range of composite properties were assessed, including adhesion and mechanical-thermal behavior. Cross-linked NR reinforced with silk fabric had better mechanical properties compared to the same NR reinforced with nylon fabric. Furthermore, silk fabric reinforced NR had a lower dissipation energy. This study combined material characterization with pilot-scale manufacturing of racing bicycle tires. It compared commercial nylon-reinforced tires with tires reinforced using silk fabric. The silk-reinforced tire performed better than the conventional nylon-reinforced tire in durability (129%), puncture resistance (157%), and cord tensile strength (243%). In addition, life cycle assessment (LCA) revealed significant environmental advantages of silk-reinforced tires, with reductions of over 80% in global warming potential (GWP), abiotic depletion of fossil resources, ozone depletion potential (ODP), and photochemical oxidation potential (POP) compared to nylon-reinforced tires. These results highlight silk fabric as a sustainable, high-performance alternative for commercial-scale, energy-saving racing bicycle tire applications
Analytical computation of five unresolved integrals in the linear theory of partially cavitating hydrofoils
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Hierarchical nanoengineered NiCo LDH@α-Fe2O3 heterostructures for optimised electrochemical capacitive performance
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Development and evaluation of a head-controlled wheelchair system for users with severe motor impairments
No full textInternational audienceThis paper presents an innovative and accessible hands-free wheelchair control system designed for individuals with severe motor impairments, particularly tetraplegic users. Unlike traditional joystick-based systems, which are often unsuitable for users with quadriplegia, our system relies on intuitive head-motion detection to enhance autonomy and ease of use. The system consists of a wearable motion-sensing cap equipped with an MPU-6050 sensor which is a 6-axis Inertial Measurement Unit (IMU) to capture head gestures, processed by an ATmega328 microcontroller (a low-power 8-bit AVR microcontroller widely used in embedded systems) integrated on an Arduino Nano development board. Wireless commands are transmitted via a Bluetooth modul
Virtual Synchronous Generator Control of Grid Connected Modular Multilevel Converters with an Improved Capacitor Voltage Balancing Method
No full textInternational audienceModular multilevel converters have emerged as a common solution in high-voltage and medium-voltage applications due to their scalability and modularity. However, these advantages come at the cost of increased control complexity, particularly when compared to other multilevel converter topologies. This paper proposes a new combined control strategy based on virtual synchronous generator (VSG) control and capacitor voltage balancing (CVB) method. The VSG control is applied for power sharing and inertia emulation to increase the dynamic response and improve system stability while the CVB method is used to redistribute the energy stored in the capacitors of the submodules (SMs) in order to ensure uniform voltage levels and equalize the voltage across the capacitors. The simulation results as well as experimental ones confirm the feasibility and effectiveness of the proposed method, enhancing the performance of the energy conversion system
Sliced Optimal Transport Plans
No full textSince the introduction of the Sliced Wasserstein distance in the literature, its simplicity and efficiency have made it one of the most interesting surrogate for the Wasserstein distance in image processing and machine learning. However, its inability to produce transport plans limits its practical use to applications where only a distance is necessary. Several heuristics have been proposed in the recent years to address this limitation when the probability measures are discrete. In this paper, we propose to study these different propositions by redefining and analysing them rigorously for generic probability measures. Leveraging the -based Wasserstein distance and generalised geodesics, we introduce and study the Pivot Sliced Discrepancy, inspired by a recent work by Mahey et al.. We demonstrate its semi-metric properties and its relation to a constrained Kantorovich formulation. In the same way, we generalise and study the recent Expected Sliced plans introduced by Liu et al. for completely generic measures. Our theoretical contributions are supported by numerical experiments on synthetic and real datasets, including colour transfer and shape registration, evaluating the practical relevance of these different solutions.</div
Cellulose nanocrystals (CNC) from Diss plant: bleaching treatment effect
No full textIn this work, we investigate the efficiency of different pretreatment methods and their impact on the characteristics of cellulose nanocrystals (CNC) extracted from the Diss plant, a widely available plant in the North African region. Two extraction methodologies were employed, focusing on the effects of bleaching treatments using hydrogen peroxide and sodium chlorite. Fourier transform infrared spectroscopy confirmed the effective removal of non-cellulosic materials, yielding CNCs with a cellulose I crystalline structure. The Zeta potential analysis revealed an increased presence of hydroxyl groups on the CNC surface. Scanning electron microscopy showed that CNCs tend to form agglomerates upon drying. Thermogravimetric analysis demonstrated that the CNCs exhibit considerable thermal stability, with degradation temperatures ranging from 100 degrees C to 350 degrees C
