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Secured-by-design systems-on-chip: a MBSE Approach
No full textInternational audienceSecurity by Design (SbD) has gained increasing interest over the past decade. While iterative processes and legacy preservation aim to reduce costs and mitigate risks through continuity, SbD encourages a break in the way we do things with a simple idea: dealing with new threats, leading to new risks, requires a complete rethink of our design processes. In embedded systems, security has been more or less left aside for a long time, with performance being the main objective. When security concerns emerged, the response was to adapt existing solutions with security patches. This is neither sustainable (to change from simple embedded systems to complex systems-onchip) nor simply effective. It is necessary to change the mindset, which will lead to new practices. But the central question is: "How can we put security at the heart of the design process?" The aim of this paper is to contribute to this reflection by providing a rapid prototyping environment (modeling and simulation-based systems engineering) for the hardware mechanisms responsible for the deployment of rights management services
Exploring the Potential of Artificial Intelligence in Individualized Cognitive Training: a Systematic Review
No full textTo tackle the challenge of responders heterogeneity, Cognitive Training (CT) research currently leverages AI Techniques for providing individualized curriculum rather than one-size-fits-all designs of curriculum. Our systematic review explored these new generations of adaptive methods in computerized CT and analyzed their outcomes in terms of learning mechanics (intra-training performance) and effectiveness (near, far and everyday life transfer effects of CT). A search up to June 2023 with multiple databases selected 19 computerized CT studies using AI techniques for individualized training. After outlining the AI-based individualization approach, this work analyzed CT setting (content, dose, etc), targeted population, intra-training performance tracking, and pre-post-CT effects. Half of selected studies employed a macro-adaptive approach mostly for multiple-cognitive domain training while the other half used a micro-adaptive approach with various techniques, especially for single-cognitive domain training. Two studies emphasized the favorable influence on CT effectiveness, while five underscored its capacity to enhance the training experience by boosting motivation, engagement, and offering diverse learning pathways. Methodological differences across studies and weaknesses in their design (no control group, small sample, etc.) were observed. Despite promising results in this new research avenue, more research is needed to fully understand and empirically support individualized techniques in cognitive training
Dynamics of niche construction in adaptable populations evolving in diverse environments
No full textInternational audienceIn both natural and artificial studies, evolution is often seen as synonymous to natural selection. Individuals evolve under pressures set by environments that are either reset or do not carry over significant changes from previous generations. Thus, niche construction (NC), the reciprocal process to natural selection where individuals incur inheritable changes to their environment, is ignored. Arguably due to this lack of study, the dynamics of NC are today little understood, especially in real-world settings. In this work, we study NC in simulation environments that consist of multiple, diverse niches and populations that evolve their plasticity, evolvability and niche-constructing behaviors. Our empirical analysis reveals many interesting dynamics, with populations experiencing mass extinctions, arms races and oscillations 1. To understand these behaviors, we analyze the interaction between NC and adaptability and the effect of NC on the population's genomic diversity and dispersal, observing that NC diversifies niches. Our study suggests that complexifying the simulation environments studying NC, by considering multiple and diverse niches, is necessary for understanding its dynamics and can lend testable hypotheses to future studies of both natural and artificial systems
Les indispensables. Sociologie des mondes militants: Sociologie des mondes militants
No full textInternational audienceVous allez lire ici des histoires de militants. Ce sont des récits passionnants sur des engagements pour rendre meilleur le monde et plus légère la vie. Des combats tristement perdus et des victoires arrachées parfois avec les dents qu’un sourire franc laisse briller au milieu de la figure. Ces récits ont été laborieusement et patiemment livrés à l’auteur par des militantes et des militants bataillant dans les domaines les plus divers, de la culture au sport, de la politique au logement, de l’hygiène du linge à la réinsertion après un passage en prison, de la protection de la vie des adolescents face à la violence du narcotrafic à la difficile relation entre religion et politique
Satellite and High-Spatio-Temporal Resolution Data Collected by Southern Elephant Seals Allow an Unprecedented 3D View of the Argentine Continental Shelf
No full textInternational audienceHigh spatial and temporal resolution hydrographic data collected by Southern Elephant Seals (Mirounga leonina, SESs) and satellite remote sensing data allow a detailed oceanographic description of the Argentine Continental Shelf (ACS). In-situ data were obtained from the CTD (Conductivity, Temperature, and Depth), accelerometer, and hydrophone sensors attached to five SESs that crossed the ACS between the 17th and 31st of October 2019. The analysis of the temperature (T) and salinity (S) along the trajectories allowed us to identify two different regions: north and south of 42°S. Satellite Sea Surface Temperature (SST) data suggests that north of 42°S, warm waters are coming from the San Matias Gulf (SMG). The high spatio-temporal resolution of the in-situ data shows regions with intense gradients along the T and S sections that were associated with a seasonal front that develops north of Península Valdés in winter due to the entrance of cold and fresh water to the SMG. The speed of the SESs is correlated with tidal currents in the coastal portion of the northern region, which is in good agreement with the macrotidal regime observed. A large number of Prey Catch Attempts (PCA), a measure obtained from the accelerometer sensor, indicates that SESs also feed in this region, contradicting suggestions from previous works. The analysis of wind intensity estimated from acoustic sensors allowed us to rule out the local wind as the cause of fast thermocline breakups observed along the SESs trajectories. Finally, we show that the maximum depth reached by the elephant seals can be used to detect errors in the bathymetry charts
Parcours d’étudiant.es en médecine intensive réanimation : motivations et représentations pour la spécialité
No full textInternational audienc
A simulation-driven supervised learning framework to estimate brain microstructure using diffusion MRI
No full textInternational audienceWe propose a framework to train supervised learning models on synthetic data to estimate brain microstructure parameters using diffusion magnetic resonance imaging (dMRI). Although further validation is necessary, the proposed framework aims to seamlessly incorporate realistic simulations into dMRI microstructure estimation.Synthetic data were generated from over 1,000 neuron meshes converted from digital neuronal reconstructions and linked to their neuroanatomical parameters (such as soma volume and neurite length) using an optimized diffusion MRI simulator that produces intracellular dMRI signals from the solution of the Bloch–Torrey partial differential equation. By combining random subsets of simulated neuron signals with a free diffusion compartment signal, we constructed a synthetic dataset containing dMRI signals and 40 tissue microstructure parameters of 1.45 million artificial brain voxels.To implement supervised learning models we chose multilayer perceptrons (MLPs) and trained them on a subset of the synthetic dataset to estimate some microstructure parameters, namely, the volume fractions of soma, neurites, and the free diffusion compartment, as well as the area fractions of soma and neurites. The trained MLPs perform satisfactorily on the synthetic test sets and give promising in-vivo parameter maps on the MGH Connectome Diffusion Microstructure Dataset (CDMD). Most importantly, the estimated volume fractions showed low dependence on the diffusion time, the diffusion time independence of the estimated parameters being a desired property of quantitative microstructure imaging.The synthetic dataset we generated will be valuable for the validation of models that map between the dMRI signals and microstructure parameters. The surface meshes and microstructures parameters of the aforementioned neurons have been made publicly available
MEALOR II Mécanique de l'Endommagement et Approche Locale de la Rupture, Ecole d'été du 21-31 août 2023
No full textInternational audienceThe MEALOR II summer school, held in Banyuls, France from August 21st to September 1st, 2023, sought to offer participants a comprehensive understanding of the physics and mechanics of brittle and ductile fracture under monotonic loading. Covering theoretical, numerical, and experimental foundations, as well as the latest applications and research developments of the local approach to fracture, the book compiles lecture materials delivered during the summer school, with a significant focus on fundamental fracture mechanisms
