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Compare quantified neural networks for MNIST (images) and N-MNIST (events) data
No full textThis study analyzes lightweight neural networks' performance with frame-based and event data from MNIST and N-MNIST datasets. We explore the impact of quantization, studying how parameter reduction (8-1 bits) and increased network depth affect the efficiency of quantized neural networks across different data types
A Hybrid Coordinated Decision-Making Method for CAVs at Unsignalized Intersection
No full textInternational audienceAiming at the Connected Autonomous Vehicles (CAVs) crossing the unsignalized intersection problem, a hybrid coordinated optimization method is studied in this paper. The proposed approach consists of a Multi-Risk Management of Cooperative Optimization approach based on the Predicted Inter-Distance Profile (MRMCO-PIDP), and Epsilon Probability Collective algorithm (Epsilon-PC) to make CAVs apply cooperative and adaptive velocity planning to navigate safely and quickly in unsignalized intersections. It is the first use of PIDP for multi-risk assessment and management for CAVs. According to the computation of PIDP metric [1] regarding other vehicles with risk of collision and its controlled minimum (mPIDP), CAVs can find the most effective speed profile for collision avoidance in an unsignalized intersection. Several random scenarios are performed in simulation to demonstrate the reliability of the proposed approach
Des forêts suisses à Wikipédia : Histoire sociale de la théorie des communs autogouvernés
No full textInternational audienceThis article highlights the socio-historical factors that have contributed to the circulation of the theory of the self-governing commons from the academic world close to the Bloomington School to the world of the Internet. At the intersection of a historical sociology of science and a social history of ideas, we show that this circulation can be understood in terms of the existence of "elective affinities" and "multi-positioned couriers" who perform a translation work between these two social worlds.Cet article met au jour les facteurs socio-historiques qui ont contribué à la circulation de la théorie des communs autogouvernés depuis le monde universitaire proche de l’École de Bloomington jusqu’au monde Internet. Au croisement d’une sociologie historique des sciences et d’une histoire sociale des idées, nous montrons que cette circulation peut se comprendre par l’existence d’« affinités électives » et de « passeurs multipositionnés » opérant un travail de traduction entre ces deux mondes sociaux
Current and future European culture of mobility: insights from in-depth conversations with thinkers
No full textInternational audienceThis paper deals with the foundations of current and past mobility cultures, identifies emerging trends and main drivers that contribute to the shaping of the future European mobility cultures, and focuses on the role of communication. The methodology adopted to better understand this complex concept involved 3 major steps: first a literature exploration, then a foresight involving strategic application of forward-looking approaches in shaping and informing public policy decisions which needed, and finally backcasting exercise to mainly build future scenarios. During these steps, we aimed to identify, involve and create a community of high level experts and thinkers in various fields: philosophy, psychology, sociology, geography, urbanism, architecture, economics, poetry, art. This involvement led to 29 scientific discussions of 3 types: 15 Talks with 16 experts, 5 Explorative Conversations with 11 experts and 9 Generative Dialogues with 11 experts. We have also organized 3 focus groups and 5 workshops to deepen our thinking on specific topics and involve a larger group of experts: Mobility values, Imagining future scenarios on mobility cultures, Public interest definition, Design a roadmap and outline feasible strategies. A survey of European citizens was carried out to involve them in an open consultation of the vision. Experts and thinkers were interviewed to stimulate discussion on how they understand mobility cultures and what drives it, to identify trends in mobility cultures and how they perceive mobility’s future. The idea was also to confront different or conflicting ideas and to identify the nuances and uncertainties, particularly with regard to the trends and future mobility cultures. As a result, we developed a vision not only of current and past mobility cultures, but especially of the expected and likely mobility future. We created 4 (extreme) political and societal scenarios for the mobility future and named them according to Greek divinities: Hercules, Themis, Hermes, and Gaia. The final results are a combination of several elements from different scenarios. The most desired future mobility clearly tends towards the Themis and Gaia cultural values of equity and well-being, while the Hermes cultural value of efficiency is perceived as driving the most likely future. This mismatch between expected and desired futures clearly expresses tensions between elements of mobility cultures. This gap points to a direction for future European mobility policy, away from efficiency and towards alternative values of sufficiency, care, and justice. Although we intended to cover the whole of Europe, Western Europe has remained relatively over-represented
Navigating the 15-minute City: First Learnings and Discussions from the Driving Urban Transitions Partnership
No full textInternational audienceIn a co-creation process, the authors of this publication identified and highlighted the research, municipal, national and european perspectives on the 15-minute City concept, brought in by different stakeholders working in the field of urban mobility. In addition, they present the results of six Critical Issues to operationalise and implement the concept that will require further attention in the upcoming years, such as social justice, the involvement of people and organising the urban mobility transition
A Novel Approach for Upper Limbs Joint Angle Measurement Using Wearable IMU Sensors
No full textInternational audienceThis paper introduces a novel method for measuring upper limb joint angles using wearable IMU sensors and a Kalman filter algorithm. The proposed method estimates 3D joint orientations without relying on magnetometer data, addressing limitations associated with traditional motion capture systems. To assess the accuracy and reliability of IMU-based measurements, a comprehensive evaluation against the gold standard Vicon system is conducted. The agreement between IMU and Vicon measurements is assessed using various error metrics, including RMSE, MAE, NMBE, and R², followed by Mann-Whitney U tests with Bonferroni correction for statistical significance. Results indicate strong correlations between IMU and Vicon data (R² values: 0.890 to 0.974, R²>0.7). RMSE (5.35° to 12.07°) and MAE (3.69° to 7.01°) values represent a small percentage of the range of motion for each joint. NMBE values are mostly close to zero, indicating minimal bias in IMU measurements. Notably, wrist flexion-extension exhibits a relatively higher NMBE (-0.839), suggesting a potential underestimation of angles in this plane of motion. Statistically significant differences (p<0.05 with Bonferroni correction) are found for all degrees of freedom, with discrepancies ranging from 1.7% to 21% of the total dataset. Smallest differences are observed for wrist flexion-extension and elbow pronation-supination, while the largest occur in elbow flexion-extension and shoulder adduction-abduction. These findings suggest the proposed algorithm’s reliability, as evidenced by strong correlation with the Vicon system and low error rates and biases for most degrees of freedom. However, larger population studies are warranted for further validation and refinement
Demand and growth regimes of the BRICs countries – the national income and financial accounting decomposition approach and an autonomous demand-led growth perspective
No full textInternational audienceWe contribute to the recent debate in post-Keynesian economics (PKE), comparative political economy (CPE) and international political economy (IPE) on growth regimes. The paper presents an analysis of changes in demand and growth regimes in the BRICs countries, Brazil, Russia, India, and China, after the Global Financial Crisis and the Great Recession of 2007–2009. It discusses and applies two approaches: a first one based on national income and financial accounting decomposition and a second one based on the Sraffian Supermultiplier (SSM) growth model, distinguishing the dynamics of autonomous expenditure growth from those of the induced components of aggregate demand. It is argued that the SSM approach provides the bridge between the traditional approach based on national income and financial accounting decomposition and the analysis of growth drivers, both in PKE as well as in CPE and IPE. This is illustrated by pointing out some changes in the underlying political economy and economic policy growth drivers in each of the countries
Dynamic substructuring for mechanical systems with frequency-dependent materials using a POD-based model reduction method
No full textInternational audienceBased on the Balanced Truncation approach, a novel methodology for the construction of a superelement for the dynamic analysis of elastic structures made with viscoelastic materials is presented. Contrary to classical modal reduction techniques (Craig-Bampton, MacNeal) where the normal modes basis must be enriched to account for damping effects, the methodology presented here takes advantage of the Golla–Hughes–McTavish rheological model (GHM) before reducing the system via the Balanced Proper Orthogonal Decomposition (BPOD). The Lagrange multipliers are finally employed to couple the reduced system to a host structure, as made in popular dynamic substructuring techniques. This method has two major advantages. First, substantial savings are achieved by the judicious combination of GHM and POD techniques. Second, the reduced system takes the form of a constant matrix of small size which permits to preserve confidentiality
Convergent scheme for a non-local transport system modeling dislocations dynamics
No full textInternational audienceIn this paper, we consider a diagonal hyperbolic, not necessarily strictly hyperbolic, nonlinear and non-local system of transport equations that arises in the theory of dislocations densities dynamics. Under certain monotony assumptions on the initial data, global existence and uniqueness results of H1loc solutions for this system was proved in Hajj (2007). We propose a natural implicit scheme verifying a gradient L² estimate at the discrete level compatible with that obtained in the continuous case in Hajj (2007). Which leads us to prove the convergence of the numerical solution to the continuous one. To our knowledge, this is the first convergent scheme proposed for this model
Collaborations et négociations des nouvelles pratiques de savoir à l’interface entre la science et la société: Journée de restitution de l'appel à projet amorçage "science et/en société" - Les méthodologies des sciences partagées Vendredi 27septembre 2024
No full textInternational audienceJointly funded by INSHS and OpenEdition, with the support of UAR 2276 for the production of a podcast, and benefiting from ongoing research undertaken in ANR Reforms project, the SAPA project aims to observe, in the course of nine public discussions, the open use of science and knowledge sharing in the digital age in a variety of social contexts, involving actors from civil society, doctors, scientists, entrepreneurs, activists, autodidacts, editors, etc., and multiplying exchange and production formats.Financé conjointement par l’INSHS et OpenEdition, en collaboration avec l’UAR 2276 pour la production d’un podcast, le projet SAvoirs PArtagés vise à observer, au cours de huit discussions publiques, les usages ouverts de la science et le partage des savoirs à l’ère digitale dans des contextes sociaux variés, en impliquant des acteur·ice·s de la société civile, médecins, scientifiques, entrepreneur·euse·s, activitstes, autodidactes, éditeur·ice·s, etc… et en multipliant les formats d’échange et de production