Multi-level agent-based modeling with the Influence Reaction principle

This paper deals with the specification and the implementation of multi-level agent-based models, using a formal model, IRM4MLS (an Influence Reaction Model for Multi-Level Simulation), based on the Influence Reaction principle. Proposed examples illustrate forms of top-down control in (multi-level) multi-agent based-simulations

Stratégies d'observation dans les simulations orientées agent

Extended version of Stratégies d'observation de simulations orientées agent, Actes des 17èmes Journées Francophones sur les Systèmes Multi-Agents (JFSMA'09), pp. 233-236National audienceL'observation de simulations orientées agent composées de nombreux agents est une tâche coûteuse en temps de calcul. Dans cet article, nous proposons deux méthodes, très simples à mettre en oeuvre, basées sur la théorie des sondages et la notion d'auto-observation, permettant d'optimiser le calcul d'observables. Ces méthodes sont évaluées et comparées empiriquement sur un problème jouet

Modélisation de la température d’un corps par automates cellulaires

International audienceDans cet article, nous traitons d'une alternative aux méthodes analytiques classiques dans le cadre de la modélisation de systèmes complexes. Devant le caractère imprévisible de ces systèmes (où le nombre de composants et l'intensité des interactions sont importants), les méthodes analytiques semblent mal adaptées et des modèles dynamiques discrets, comme les automates cellulaires, peuvent permettre de faireémerger des comportements globaux complexes en déterminant simplement le comportement local et les interactions d'entités primitives. Nous illustrons notre propos en nous intéressantà un problème issu de la médecine légale : la modélisation du comportement thermique d'un cadavre. Aucun des modèles de température actuels, empiriques ou basés sur les lois physiques de transfert de chaleur, ne prend en compte des simulations sous températures variables. Nous proposons une solution qui remédieà ce problème. Nous en détaillons les spécifications, implémentations et résultats. Nous terminons sur l'utilisation de nos travaux, intégrés au sein d'un système multi-agents, et les perspectives de travail

Thermoregulation in P. Terraenovae aggregations, an agent-based approach

International audienceThis paper deals with an important issue of forensic entomology: the estimation of the temperature in a "maggot mass". An agent-based model of the thermoregulation behaviour of fly (Protophormia terraenovae) larvae is described. Simulation results show that the model reproduces an important observed pattern and thus, might be used in entomological expertises

A simulation-based model of abduction

International audienceAbduction, or Inference to the Best Explanation (IBE), is a reasoning process that generates possible explanations from a set of "surprising" observations. In this paper, a simulation-based model of abduction is introduced. This model is then implemented to develop a decision support system in the field of Forensic Entomology to help forensic scientists solve complex cases

Super-twisting sliding mode controller for freeway ramp metering

Colloque avec actes et comité de lecture. internationale.International audienceIn this paper we propose a new feedback controller for freeway ramp metering. It is based on a second order sliding mode technique called super twisting sliding mode controller (STSMC). It is a simple and robust controller. It is less sensitive to parameter values and the model uncertainty with less problem of chattering phenomenon compared to the first order sliding mode controller. And then, this new controller is compared with a well known feedback controller for freeway ramp metering called ALINEA. The simulations show a good result of the new controller for freeway ramp metering. Moreover, compared to ALINEA, the STSMC can cope better the system in term of robustness and uncertainty

A Multilevel Agent-Based Approach to model and simulate Systems of Systems

International audienceThis article proposes a generic modeling approach of systems of systems (SoS) using agent-based modeling (ABM). SoSs are large scale systems including numerous-possibly heterogeneous-interacting component systems (CS) evolving in a dynamic environment. The aim of this article is to provide generic formalism allowing to represent and control the whole complexity of a SoS using agent-based simulations. Models generated using this formalism encompass static and dynamic aspects of SoSs. They consider reorganization of SoSs caused by changes of goals or subsystem capacity. All these elements are illustrated in this article using a SoS case study of Intelligent Automated Vehicles (IAV) initiated by the InTraDE (Intelligent Transportation for Dynamic Environment) European project to automate the port container logistic

Biochemical disorders induced by cytotoxic marine natural products in breast cancer cells as revealed by proton NMR spectroscopy-based metabolomics

International audienceMarine plants and animals are sources of a huge number of pharmacologically active compounds, some of which exhibit antineoplastic activity of clinical relevance. However the mechanism of action of marine natural products (MNPs) is poorly understood. In this study, proton NMR spectroscopy-based metabolomics was applied to unravel biochemical disorders induced in human MCF7 breast cancer cells by 3 lead candidate anticancer MNPs: ascididemin (Asc), lamellarin-D (Lam-D), and kahalalide F (KF). Asc, Lam-D, and KF provoked a severe decrease in DNA content in MCF7 cells after 24h treatment. Asc and Lam-D provoked apoptosis, whereas KF induced non-apoptotic cell death. Metabolite profiling revealed major biochemical disorders following treatment. The response of MCF7 tumor cells to Asc involved the accumulation of citrate (×17 the control level, <0.001), testifying enzyme blockade in citrate metabolism, and the accumulation of gluconate (×9.8, <0.005), a metabolite never reported at such concentration in tumor cells, probably testifying glycolysis shutdown. The response to Lam-D involved the accumulation of aspartate (×7.2, <0.05), glutamate (×14.7, <0.05), and lactate (×2.3, <0.05), probably in relation with the targeting of the malate-aspartate shuttle, as discussed. The response to KF involved increased lipid accumulation (polyunsaturated fatty acids ×9.8, <0.05), and phospholipid and acetate derivative alterations. Altogether, this study demonstrates the potential of proton NMR spectroscopy-based metabolomics to help uncover metabolic targets and elucidate the mechanism of cytotoxicity of candidate antineoplastic MNPs