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An Open-Source Cognitive Test Battery to Assess Human Attention and Memory
No full textInternational audienceCognitive test batteries are widely used in diverse research fields, such as cognitive training, cognitive disorder assessment, or brain mechanism understanding. Although they need flexibility according to their usage objectives, most test batteries are not available as open-source software and are not be tuned by researchers in detail. The present study introduces an open-source cognitive test battery to assess attention and memory, using a javascript library, p5.js. Because of the ubiquitous nature of dynamic attention in our daily lives, it is crucial to have tools for its assessment or training. For that purpose, our test battery includes seven cognitive tasks (multiple-objects tracking, enumeration, go/no-go, load-induced blindness, task-switching, working memory, and memorability), common in cognitive science literature. By using the test battery, we conducted an online experiment to collect the benchmark data. Results conducted on 2 separate days showed the high cross-day reliability. Specifically, the task performance did not largely change with the different days. Besides, our test battery captures diverse individual differences and can evaluate them based on the cognitive factors extracted from latent factor analysis. Since we share our source code as open-source software, users can expand and manipulate experimental conditions flexibly. Our test battery is also flexible in terms of the experimental environment, i.e., it is possible to experiment either online or in a laboratory environment
Interaction inertielle sol-structure d'un massif renforcé par inclusions rigides
No full textInternational audienceInteraction inertielle sol-structure d'un massif renforcé par inclusions rigide
Méthode des éléments de frontière pour la mécanique des failles et le contrôle sismique
No full textInternational audienceCe travail consiste à vérifier numériquement des stratégies de contrôle de séismes par injection de fluide dans le sol. Nous étudions les capacités des méthodes d’éléments de frontière (BEMs) à simuler des séquences de glissements sismiques et asismiques en géomécanique. Un algorithme basé sur les BEMs accélérées par FFT est considéré, validé, et des résultats sont présentés pour un problème simple de mécanique des failles. Les challenges en lien avec l’extension des BEMs accélérées pour incorporer les couplages multi-physiques en jeu sont discutés
Damage modeling of MWCNT reinforced Carbon/Epoxy composite using different failure criteria: a comparative study
No full textInternational audienceIn the present study, the progressive failure on MWCNT reinforced 5-Harness satin fabric composite materials is analysed using finite element (FE) analysis for Hashin and Puck failure criteria and degradation models. The progressive failure analysis of laminated composites is carried out on open-hole tensile (OHT) and short beam shear test (SBST) specimens for different volume percentages of MWCNT as reinforcements. The inter-ply delamination in CNT reinforced laminated composites is demonstrated through cohesive zone modeling. The load–displacement responses obtained from FE analyses are with a reasonable agreement when compared with available experimental data in the literature. Further, the effect of MWCNTs are demonstrated on fiber fracture and inter-fiber crack in longitudinal and transverse directions, and on matrix failure using sub-modeling of mesoscopic representative volume cell. The damage propagation was retarded due to the addition of CNT as reinforcement up to a volume percentage of 2.0%. FE simulations for sub-modeling confirmed that the presence of MWCNTs in woven composites decreased the percentages of damaged regions especially fiber, matrix, and shear damages to yarns. The flexural strength degradation of SBST samples was observed mainly due to delaminations between layers. Sensitivity analysis and uncertainty quantification have been performed for the influencing input parameters used in FE simulations on the critical output parameters, especially for peak load and stiffness of the OHT laminated composite specimens
A Revised Model of Ammonium Perchlorate Combustion with Detailed Kinetics
No full textInternational audienceIn this study, we propose a revised detailed kinetic model for ammonium perchlorate (AP) combustion, leveraging recent advances in the modelling of ammonia chemistry. The gas-phase mechanism is validated against data on species sampling in jet-stirred reactors, laminar flame speed measurements, and ignition delay time. A new model of AP decomposition in the condensed phase is proposed to be used with the gasphase mechanism. The AP laminar flame is then simulated in the 1D coupled approach. These calculations provide results on the regression rate, surface temperature, temperature sensitivity and species profiles for a prescribed initial temperature of AP and ambient pressure. Stability analysis of the coupled model is carried out employing the Zel'dovich-Novozhilov method
Data muling: an innovative solution to extend ranges and data rate
No full textInternational audienceThe emergence of new maritime activities, such as the search for mines with AUVs or wind turbine monitoring, requires more and more long-range, high-speed communications. However, in the underwater environment, no conventional wireless communication means allow this. We propose a data muling solution, i.e. the use of mobile agents spread between the data source and the data destination. These agents communicate using short range wireless communication and carry the data in internal memory from one point to another. By doing this, we show we can significantly increase the throughput of longrange communication. In this article, we will mainly focus in a 2D plan and the study of theoretical gain of this method and expose a example where data muling is interesting. In addition, we introduce a metric to choose the characteristic quantities for designing and implementing such a solution
Self‐heating measurements under cyclic loading to identify history effects on HCF properties of high‐strength low‐alloy steel: Part II—Modeling
No full textInternational audienceThe present paper proposes a new version of a model for high cycle fatigue of steels able to take load history effects into account. This model is developed in a probabilistic two-scale framework. The proposed model accounts not only for the failure of samples under high cycle loadings but also for the thermal effects during cycling in a unified theoretical framework. Thus, an ad hoc identification procedure, essentially based on self-heating tests under cyclic loadings provided in the accompanying paper, is proposed. The model was then validated by predicting the effect of a pre-cycling loading on S-N curves
On Earthlings and Aliens: Space Mining and the Challenge of Post-Planetary Eco-Criticism
No full textInternational audienceThis paper examines what I call post-planetary ecologies, basically the logics of ecological thinking that will emerge once the human lifeworld begins to meaningfully establish itself in outer space, a major step towards which will occur with the onset of space mining operations. The text itself is less a full treatment of post-planetary ecological thought as a call for a reconsideration of eco-criticism in light of the emergent post-planetary paradigm, with an emphasis on the emergent risks and dangers that might accompany any attempts to become post-planetary
