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Discrete -theorem for a finite volume discretization of a nonlinear kinetic system: application to hypocoercivity
No full textIn this article, we study the long-time behavior of a finite-volume discretization for a nonlinear kinetic reaction model involving two interacting species. Building upon the seminal work of [Favre, Pirner, Schmeiser, ARMA, 2023], we extend the discrete exponential convergence to equilibrium result established in [Bessemoulin-Chatard, Laidin, Rey, IMAJNA, 2025], which was obtained in a perturbative framework using weighted estimates. The analysis applies to a broader class of exponentially decaying initial data, without requiring proximity to equilibrium, by exploiting the properties of the Boltzmann entropy. The proof relies on the propagation of the initial bounds, derived from monotonicity properties of the scheme, allowing controlled linearizations within the nonlinear entropy estimates. Moreover, we show that the time-discrete dissipation inherent to the numerical scheme plays a crucial stabilizing role, providing control over the nonlinear terms
Modélisation numérique des glissements inter-plis dans un renfort cousu (NCF) à l'échelle macroscopique
No full textInternational audienceModélisation numérique des glissements inter-plis dans un renfort cousu (NCF) à l'échelle macroscopiqu
Influence inattendue de la réticulation de matrices époxy sur la résistance en compression de composites à fibres continues
No full textInternational audienceInfluence inattendue de la réticulation de matrices époxy sur la résistance en compression de composites à fibres continue
Crossing the line: Multi-layer analysis and the identification of different borderlines
No full textInternational audienceThis paper introduces a volume that brings together specialists in lithic studies to explore how this proxy can reveal different spatial patterns across a large European territory. It examines how diverse behaviours in various environmental and geographical areas can enhance our understanding of social processes during European neolithisation. Initially, we investigate the concept of borders and borderlines, proposing models based on the space considered as a border, the presence of sought-after resources within this space, the agents present, and the nature of interactions between these agents. Subsequently, we discuss the potential of lithic analysis for identifying social groups and different types of borders. Neolithic cultural entities have primarily been defined through typo-stylistic analysis of pottery, while lithics are underutilised in this context. Lithics, however, offer a valuable proxy for understanding the spatial distribution of these entities. Petrographic studies now allow us to precisely define lithic sources, and all actions carried out on these raw materials are readable. Lithics thus enable the tracking of raw material origins and the movement of these materials within a given area. Establishing these circulation networks is crucial for understanding the spaces occupied by prehistoric people and the nature of their interactions. This approach allows us to map and compare spatial groupings based on consumer and producer perspectives. We argue for the necessity of multi-proxy studies and modelling to gain new insights into spatial grouping patterns and their evolution, particularly by considering borderlines at the scale of social groups
Multi-View and Multi-Type Feature Fusion Rotor Biofouling Recognition Method for Tidal Stream Turbine
No full textInternational audiencePower generation is affected and structural instability may occur when biofouling attaches to the rotor of tidal stream turbines (TSTs). Image signals are used to identify biofouling for biofouling recognition, thus achieving on-demand maintenance, optimizing power generation efficiency, and minimizing maintenance costs. However, image signals are sensitive to background interferences, and underwater targets blend with the water background, making it difficult to extract target features. Changes in water turbidity can affect the effectiveness of image signal biofouling recognition, which can lead to reduced recognition accuracy. In order to solve these problems, a multi-view and multi-type feature fusion (MVTFF) method is proposed to recognize rotor biofouling on TSTs for applications in TST operation and maintenance. (1) Key boundary and semantic information are captured to solve the problem of background feature interference by comparing and fusing the extracted multi-view features. (2) The local geometric description and dependency are obtained by integrating contour features into multi-view features to address the issue of the target mixing with water. The mIoU, mPA, Precision, and Recall of the experimental results show that the method achieves superior recognition performance on TST datasets with different turbidity levels
African Geo-Ecclesiological Conceptions at the Time of the Return to the Empire (533–569)
No full textInternational audienc
A Comparative Investigation of Undergraduate Dental Student Stress in the Management of Deep and Moderate Carious Lesions
No full textInternational audienceABSTRACT Aim The primary objective of this clinical study was to analyse, through physiological and psychological parameters, undergraduate dental student stress during the management of deep compared with moderate carious lesions. Additional objectives aimed to compare student confidence, anxiety and satisfaction during deep and moderate caries management and their perception of the quality of teaching they received regarding these treatments. Methodology In this crossover study, 35 clinical students treated deep and moderate caries on permanent vital teeth in adult patients with no history of spontaneous pain. The STAI‐State (STAI‐S) anxiety questionnaire was completed preoperatively. Stress‐VAS (visual analogic scale) and confidence‐VAS scores were collected during the preoperative (before anaesthesia), perioperative (end of caries excavation) and postoperative (after patient left) phases of both caries management. Cardiovascular parameters (blood pressure and heart rate) were collected during the same stages. A satisfaction‐VAS was completed postoperatively. The effects of the depth of the caries, time and student demographics on preoperative anxiety (STAI‐S), pre‐, peri‐ and postoperative stress, confidence, blood pressure and heart rate, as well as postoperative satisfaction, were assessed using Mixed ANOVA with multiple pairwise comparisons. The statistical analysis was performed with IBM SPSS. A questionnaire assessing teaching adequacy was completed after each treatment. Results The treatment of deep caries led to a significantly higher level of stress and a significantly lower level of confidence among students than the treatment of moderate caries, pre‐, per‐ and post‐operatively ( p ≤ 0.05). Student preoperative anxiety was significantly higher in cases of deep caries, and their post‐operative satisfaction was significantly lower. However, there was no significant difference between the two groups in terms of cardiovascular parameters at any stage. There was no influence of the student year of study on the parameters examined; however, gender influenced confidence at all times combined, as well as preoperative stress, with females less confident and more stressed than males. The median level of perceived teaching ‘adequacy’ was higher for moderate caries than for deep caries. Conclusions Within the limits of this study, the management of deep carious lesions is associated with a higher level of stress among students compared with moderate caries
Energy management in networked microgrids: A comparative study of hierarchical deep learning and predictive analytics techniques
No full textInternational audienceThe management of renewable energy is one of the most important areas in the ability to use resources efficiently and ensure stability in the production of energy and the grid. This paper focuses on a networked microgrid (MG) system which is composed of multiple energy sources including biomass, photovoltaic (PV) solar panels, wind turbines (WTs), battery energy storage systems (BESS), and pumped hydro storage. The study analyzes an energy management method based on hierarchical deep learning (HDL) through several scenarios. These include normal operation, peak load, changes in renewable energy generation finding faults and odd events extreme weather, cost-effective energy distribution, and long-term planning. The HDL approach uses predictive analysis real-time data, and layered control algorithms to improve energy distribution strategies, make operations more flexible, and help provide grid support services. This provides a complete outlook on how efficient it is in different operating environments. Finally, the study employs the MATLAB/Simulink environment to validate the efficacy and accuracy of the proposed energy management systems (EMSs) strategy
Using Marine Sediments to Improve the Mechanical Behaviour of Earthen Materials
No full textInternational audienceEarth construction is emerging as a sustainable and local solution for reducing the environmental impact of the construction industry. Numerous research initiatives are currently revitalising this traditional construction material, gathering many experts. Earth is a mix of particles of various sizes, from clay and silt to sand and gravel. These materials can be used for structural or non-structural purposes, with compressive strengths ranging from 1 to 10 MPa. They also offer superior indoor hygrometric regulation properties. However, their water sensitivity poses durability issues. Recently, low-tech stabilisation solutions have emerged to enhance water resistance. Simultaneously, Europe dredges 50 million cubic meters of marine sediments annually, with France contributing significantly. The traditional solution of sea disposal raises environmental concerns, leading to stricter regulations favouring sediment valorisation. Like earth, sediments are mainly a mix of mineral particles but may also contain other pollutants. Although these sediments present technical and environmental challenges, their use reduces the need for natural resource extraction. Various solutions have been tested, including their application in earth construction. This proposed work evaluates the potential of incorporating sediments into earthen materials, examining the effects of salt and the possibility of stabilization with locally sourced seaweed extracts
Comprehensive Geriatric Assessment and Its Clinical Correlates among Hospitalized Older Adults in the Brazilian Amazon: A Descriptive Cohort Study
No full textInternational audienceAims: This study aimed to evaluate the functional, clinical, and cognitive profiles of hospitalized older adults in a general hospital in the Brazilian Amazon, contributing to understanding the relationship between frailty, cognitive decline, and functionality during hospitalization. Study Design: Prospective and analytical cohort study. Place and Duration of Study: Conducted at Hospital Jean Bitar, Belém, Pará, Brazil, from March to June 2023. Methodology: The study included 45 patients aged 65 years or older, assessed within 48 hours of admission using validated instruments such as the Clinical Frailty Scale (CFS), 10-Point Cognitive Screener (10-CS), Katz Index for Basic Activities of Daily Living (BADL), and Lawton Scale for Instrumental Activities of Daily Living (IADL). Statistical analyses were performed using BioEstat® 5.4, applying G and Chi-Square tests (α = 0.05). Results: The mean age was 76.3 years, with a slight predominance of females (51.1%, p = 0.8815). The most frequent admission diagnoses were gastrointestinal bleeding (24.4%) and consumptive syndrome (22.2%). A statistically significant association was found between sex and cognitive impairment (p = 0.0030; Cramer’s V = 0.42), with females showing a higher prevalence of probable cognitive impairment (73.9%). The 10-CS revealed a significant difference across cognitive categories (p = 0.0006; V = 0.51). The CFS demonstrated a significant association with mortality risk (p = 0.0282), where higher frailty scores correlated with greater mortality probability. Conclusion: Functional dependence and cognitive decline were prevalent among hospitalized older adults, particularly among females, with significant associations between frailty, cognition, and mortality. These findings reinforce the need for comprehensive geriatric assessments to guide care strategies and improve quality of life in this population