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Le déclin de la notion de préjudice en droit de la responsabilité civile extracontractuelle
No full textInternational audienceQuel est le point commun entre la survenance d’une marée noire, l’angoisse ressentie devant l’imminence de sa propre mort ou encore l’esclavage sexuel ? Dans ces différents cas, et dans bien d’autres encore, le droit s’efforce d’identifier un préjudice aux fins d’indemniser la victime. On parle ainsi de préjudice écologique, d’angoisse de mort imminente ou d’avilissement.Mais alors, s’il est sans cesse découvert de nouvelles formes de souffrance, et si les tribunaux les prennent en considération de façon toujours plus libérale, cette course effrénée à l’indemnisation n’engendre-t-elle pas des conséquences majeures sur la notion même de préjudice ? De ce point de vue, il s’avère que la notion a perdu au fil du temps certaines de ses caractéristiques fondamentales alors que, dans le même temps, elle se disperse et perd de sa substance, principalement en matière extrapatrimoniale. S’ensuit un déclin de la notion de préjudice dont on peut se demander s’il est un mal nécessaire ou une incitation à redéfinir les contours de celle-ci
Local static output-feedback control for Takagi-Sugeno fuzzy descriptor models
No full textInternational audienceThis paper introduces a novel local synthesis condition for static output-feedback (SOF) control of continuous-time Takagi-Sugeno (TS) fuzzy descriptor models. A key feature of the proposed approach is the local asymptotic stability of the origin of the closed-loop system, which distinguishes it from other works in the literature. This ensures the reliable operation of the closed-loop system, as its trajectories remain within the estimated region of attraction that is obtained inside the validity domain of the TS fuzzy descriptor model. In particular, the proposed condition does not impose any structural constraints on the output matrix and avoids the need for matrix-equality constraints, similarity transformations, or iterative procedures. Numerical experiments demonstrate the effectiveness and potential of the proposed method
Development of a smart farming tool to monitor the degree of dew retting of flax stems
No full textInternational audienceFlax fibres are a natural, sustainable product which have applications ranging from textiles to composite materials. A process known as 'retting' is required to facilitate the mechanical extraction of flax fibres from their associated stems. The goal of retting is to break down the binding material (pectin) holding the fibre bundles to the core and epidermis of the stem, not the pectin which holds the single fibres together which form long, practical 'technical' fibres. For natural dew retting, there is therefore an optimum retting period: insufficient retting renders fibre extraction difficult and leads to low yield, whereas excessive retting can lead to poor technical fibre quality. For centuries, the timing of the retting termination has been evaluated by artisanal means. Today, modern technology enables one to envisage tools that indicate optimal retting. Here, we demonstrate the development of a smart tool combining mechanics, digital microscopy, and image analysis. The cracking of the outer tissue of the flax stems, due to mechanical torsion applied to the stems by the tool, is quantified using optical microscopy and image analysis, and is demonstrated to serve as an observable indicator of the degree of retting of the stems
Exploring MIMO Correlation Matrix Distance for Cell-free V2I Channel Characterization
No full textInternational audienceThis letter investigates the stationarity characteristics of vehicle-to-infrastructure (V2I) channels in a cell-free context, based on 5.89 GHz field measurements. The Correlation Matrix Distance (CMD) metric is used to quantify the stationarity time of both individual access point (AP)-to-user channels and the collective channel formed by stacking multiple APs. Results show that with two APs, the collective channel's stationarity time is similar to that of the most non-stationary AP. However, when the number of APs increases to four, the collective channel's stationarity time decreases significantly, falling below that of any individual AP. This demonstrates that increasing spatial distribution in cell-free architectures amplifies the impact of local non-stationarities, especially near APs. These findings highlight the importance of thoroughly characterizing stationarity in cellfree systems, particularly as the network scales.</div
Development of an Extended-Band mTRL Calibration Kit for On-Wafer Characterization of InP-HEMTs up to 1.1 THz
No full textInternational audienceIn this work, we present a wideband on-wafer characterization technique for In-AlAs/InGaAs/InAs InP-based high-electron mobility transistors (HEMTs) using an optimized multiline Thru-Reflect-Line (mTRL) calibration kit. Our goal is to directly extract transition frequency f T and maximum frequency of oscillation f max values from S-parameters measurements with frequencies up to 1.1 THz and overcome the limitations of the traditional 20 dB/dec extrapolation method using lower-frequency band measurements. Indeed, as the state-of-the-art transistors now exhibit cutoff frequencies exceeding 1 THz, standard low-frequency extrapolation methods become increasingly inaccurate. Full-wave electromagnetic simulations were used to design low-loss coplanar waveguide (CPW) access structures with stable impedance and minimal parasitic effects. These structures were co-fabricated with HEMTs and calibration standards on the same InP substrate. The 2-finger transistor with a 80 nm gate length exhibits a directly measured f T = 320 GHz and f max = 800 GHz. The technique showed high consistency across six frequency bands and confirms that direct broadband measurement with mTRL improves accuracy. This work highlights the metrological strength of mTRL-based setups for next-generation THz device characterization.</div
Utilisations de l'Intelligence Artificielle générative pour l'autoformation et la stimulation de la créativité
No full textInternational audienceUtilisations de l'Intelligence Artificielle générative pour l'autoformation et la stimulation de la créativit
A critical review on neurodegenerative biomarker diagnostics: where is the field heading to?
No full textInternational audienceNeurodegenerative diseases (NDD), a collection of disorders with different underlying causes and clinical presentations, are recognized as a major area of concern of our society today. The most common NDD are Parkinson’s disease (PD), Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), and Huntington’s disease, each one of them being characterized by the progressive degradation of nerve cells and accumulation of misfolded and aggregated proteins in the affected brain region. Diagnosing NDD is challenging, due to the heterogeneity of the disease and the overlap of symptoms. Yet, early detection and accurate diagnosis are crucial for effective NDD management. With the emergence of disease-modifying therapies for AD, monitoring disease progression and treatment success is becoming essential. The future of NND diagnostics is focusing on developing less invasive, cost-effective strategies that enable early NDD identification and detection with improved patient outcomes. The integration of biotechnology and nanotechnology is seen as crucial for advancing the analytical science aspect of NDD. The creation of these innovative tools and methodologies is on the verge of enabling new possibilities for clinical diagnostics, but is also faced with several hurdles that will be critically evaluated
Power of two fine-tuning for patient-specific cardiac arrhythmia recognition
No full textInternational audienceDeep learning is one of the main solution in cardiac arrhythmia classifier for its excellent performances. Research aims to embed these classifiers as near as possible from the sensors to process the data in real time and get ride of the wireless communication drawbacks. This work investigates the performance of a hardware-friendly quantified learning framework that addresses the issue of data confidentiality. It achieves the same performance than the state of the arts without data augmentation. It is also compatible with fine-tuning increasing the state of the art performances by up to 11 points with a model ×25000 smaller.</div
Integrated Electrochemical Conversion of Plastic Waste and CO <sub>2</sub> to Formate Using Non-Noble-Metal Catalysts: <i>In Situ</i> Raman Study.
No full textInternational audiencePoly(ethylene terephthalate) (PET), a common single-use plastic, significantly contributes to CO2 emissions when discarded or incinerated. In this study, we have employed an innovative approach by combining electrochemical PET hydrolysate oxidation and CO2 reduction reaction (CO2RR) to simultaneously produce formate in a single electrochemical cell. Utilizing simple electrochemical methods, a porous 3D carbon felt (CF) electrode was anodically oxidized to produce activated carbon felt (aCF). The latter was used as a support for the electrochemical deposition of bismuth oxide carbonate (Bi2O2CO3) and nickel cobalt phosphate (NiCoPOx) for CO2RR and anodic PET hydrolysate oxidation, respectively. In situ Raman analysis indicated that MOOH (M = Ni, Co) intermediates acted as active sites for PET hydrolysate oxidation, with the ability to regenerate into lower-valence nickel species post-reaction. Both electrodes exhibited Faradaic efficiencies (FEs) exceeding 90% in their respective half-cell reactions. When implemented in a two-electrolyzer setup, a combined FE of up to 158% for both reactions was recorded at a remarkably low cell voltage of 1.8 V. This research highlights the use of non-noble metals to transform PET plastic waste and CO2 into valuable fuels
Optimisation des fonctions freinage et traction à des fins de réduction des émissions dans le domaine ferroviaire
No full textRecent studies show that underground metro systems have high concentrations of particulate emissions, primarily generated by braking systems, which pose significant public health risks. This thesis, conducted within the framework of the BREAQ project, aims to reduce these emissions by optimizing train driving profiles.The research focuses on developing optimal train control strategies using indirect methods to minimize brake-related emissions. First, to effectively handle constraints in optimal control problems, a numerical continuation procedure is implemented, enabling an iterative incorporation of constraints. Additionally, two initialization techniques are proposed to address the well-known challenge of solving boundary value problems arising from indirect methods. The effectiveness of these tools is demonstrated through numerical examples before being applied to the main problems of this thesis.Building upon these methodological developments, the thesis first tackles the classic eco-driving problem, incorporating a variable power efficiency model. The results indicate that this approach outperforms the results with affine power models. Moreover, a tradeoff analysis between journey time and energy consumption highlights its potential application in designing more eco-friendly railway timetables.Expanding on the eco-driving problem, a multi-objective optimal control problem, termed as wear-aware eco-driving problem, is formulated to minimize brake emissions. The findings reveal that for a given journey duration, brake emissions can be reduced at the cost of increased energy consumption. This method provides train operators with a practical tool to customize driving profiles based on operational priorities, balancing energy efficiency and wear reduction. Such an approach could be particularly beneficial for mitigating brake emissions in underground metro networks.Finally, a preliminary experimental study is conducted on a reduced-scale brake testbench to gain insights into the dynamics of brake temperature and particulate emissions. Preliminary models of brake temperature and particles are proposed. These findings lay the groundwork for developing more accurate models in future research.Des études récentes montrent que les systèmes de métro souterrains présentent des concentrations élevées d’émissions particulaires, principalement générées par les systèmes de freinage, constituant un risque important pour la santé publique. Cette thèse, réalisée dans le cadre du projet BREAQ, vise à réduire ces émissions en optimisant les profils de conduite des trains.Les travaux de recherche portent sur le développement de stratégies de commande optimale des trains en utilisant des méthodes indirectes afin de minimiser les émissions liées au freinage.Tout d’abord, pour gérer efficacement les contraintes dans les problèmes de commande optimale, une procédure de continuation numérique est mise en œuvre, permettant une intégration itérative des contraintes. Deux techniques d’initialisation sont proposées pour résoudre le problème bien connu de l’initialisation des solveurs de problèmes aux deux bouts (Boundary Value Problems). L’efficacité de ces outils est démontrée à l’aide d’exemples numériques avant d’être appliquée aux problématiques principales de cette thèse.En s’appuyant sur ces développements méthodologiques, la thèse aborde d’abord le problème classique de l’éco-conduite en intégrant un modèle d’efficacité énergétique non linéaire. Les résultats indiquent que cette approche surpasse ceux obtenus avec des modèles affine. De plus, l’analyse des compromis entre la durée du trajet et la consommation d’énergie met en évidence le potentiel de cette approche pour les opérateurs ferroviaires.Ensuite, un problème de commande optimale multi-objectifs, tenant compte simultanément d’un critère énergétique et de l’usure des freins, est formulé afin de minimiser les émissions de freinage. Les résultats montrent que, pour une durée de trajet donnée, il existe un compromis entre les émissions et l’augmentation de la consommation d’énergie. Cette méthode offre aux opérateurs ferroviaires un outil pratique leur permettant d’adapter les profils de conduite en fonction des priorités opérationnelles, en équilibrant efficacité énergétique et réduction de l’usure. Une telle approche pourrait être particulièrement bénéfique pour la réduction des émissions de freinage dans les réseaux de métro souterrains.Enfin, une étude expérimentale préliminaire est réalisée sur un banc d’essai de freinage à échelle réduite afin de mieux comprendre la dynamique de la température de freinage et des émissions particulaires. Des modèles préliminaires de température des freins et d’émissions de particules sont proposés. Ces résultats constituent une base pour le développement de modèles plus précis dans les recherches futures