Performance Evaluation of Threshold -Based TOA Estimation Techniques Using IR-UWB Indoor Measurements

International audienceUltra-wide bandwidth (UWB) technology is a viable candidate for enabling accurate localization through time of ar- rival (TOA) based ranging techniques. These ranging techniques exploit the high time resolution of the UWB signals to estimate the TOA of the first signal path. Nevertheless, these techniques are facing the problem of proper multipath mitigation especially in harsh propagation environments in which the first path may not exist or it may not be the strongest. This paper presents a realistic comparison between the ranging performances of four threshold-based TOA estimation techniques using experimental data collected from an IR-UWB indoor propagation measurement campaign performed in an office building

Agent Bodies: An Interface Between Agent and Environment

The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-319-23850-0_2Interfacing the agents with their environment is a classical problem when designing multiagent systems. However, the models pertaining to this interface generally choose to either embed it in the agents, or in the environment. In this position paper, we propose to highlight the role of agent bodies as primary components of the multiagent system design. We propose a tentative definition of an agent body, and discuss its responsibilities in terms of MAS components. The agent body takes from both agent and environment: low-level agent mechanisms such as perception and influences are treated locally in the agent bodies. These mechanism participate in the cognitive process, but are not driven by symbol manipulation. Furthermore, it allows to define several bodies for one mind, either to simulate different capabilities, or to interact in the different environments - physical, social- the agent is immersed in. We also draw the main challenges to apply this concept effectively.Saunier, J.; Carrascosa Casamayor, C.; Galland, S.; Kanmeugne, PS. (2015). Agent Bodies: An Interface Between Agent and Environment. En Agent Environments for Multi-Agent Systems IV. 4th International Workshop, E4MAS 2014 - 10 Years Later, Paris, France, May 6, 2014. 25-40. doi:10.1007/978-3-319-23850-0_2S2540Barella, A., Ricci, A., Boissier, O., Carrascosa, C.: MAM5: Multi-agent model for intelligent virtual environments. In: 10th European Workshop on Multi-Agent Systems (EUMAS 2012), pp. 16–30 (2012)Behe, F., Galland, S., Gaud, N., Nicolle, C., Koukam, A.: An ontology-based metamodel for multiagent-based simulations. Int. J. Simul. Model. Pract. 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Autonomous Agents and Multiagent Systems (AAMAS 2015), Istanbul, Turkey, May 2015Galland, S., Gaud, N., Demange, J., Koukam, A.: Environment model for multiagent-based simulation of 3D urban systems. In: the 7th European Workshop on Multiagent Systems (EUMAS 2009), Ayia Napa, Cyprus, December 2009 (paper 36)Gechter, F., Contet, J.M., Lamotte, O., Galland, S., Koukam, A.: Virtual intelligent vehicle urban simulator: application to vehicle platoon evaluation. Simul. Model. Practice Theor. (SIMPAT) 24, 103–114 (2012)Gibson, J.J.: The Theory of Affordances. Hilldale, USA (1977)Gouaïch, A., Michel, F., Guiraud, Y.: MIC $$^{*}$$ : a deployment environment for autonomous agents. In: Weyns, D., Van Dyke Parunak, H., Michel, F. (eds.) E4MAS 2004. LNCS (LNAI), vol. 3374, pp. 109–126. Springer, Heidelberg (2005)Gouaïch, A., Michel, F.: Towards a unified view of the environment (s) within multi-agent systems. Informatica (Slovenia) 29(4), 423–432 (2005)Helleboogh, A., Vizzari, G., Uhrmacher, A., Michel, F.: Modeling dynamic environments in multiagent simulation. Int. J. Auton. Agents Multiagent Syst. 14(1), 87–116 (2007)Ketenci, U.G., Bremond, R., Auberlet, J.M., Grislin, E.: Drivers with limited perception: models and applications to traffic simulation. Recherche transports sécurité, RTS (2013)Michel, F.: The IRM4S model: the influence/reaction principle for multiagent based simulation. ACM, May 2007Okuyama, F.Y., Bordini, R.H., da Rocha Costa, A.C.: ELMS: an environment description language for multi-agent simulation. In: Weyns, D., Van Dyke Parunak, H., Michel, F. (eds.) E4MAS 2004. LNCS (LNAI), vol. 3374, pp. 67–83. Springer, Heidelberg (2005)Platon, E., Sabouret, N., Honiden, S.: Environmental support for tag interactions. In: Weyns, D., Van Dyke Parunak, H., Michel, F. (eds.) E4MAS 2006. LNCS (LNAI), vol. 4389, pp. 106–123. Springer, Heidelberg (2007)Ribeiro, T., Vala, M., Paiva, A.: Censys: a model for distributed embodied cognition. In: Aylett, R., Krenn, B., Pelachaud, C., Shimodaira, H. (eds.) IVA 2013. LNCS, vol. 8108, pp. 58–67. Springer, Heidelberg (2013)Ricci, A., Viroli, M., Omicini, A.: Programming MAS with artifacts. In: Bordini, R.H., Dastani, M., Dix, J., El Fallah Seghrouchni, A. (eds.) PROMAS 2005. LNCS (LNAI), vol. 3862, pp. 206–221. Springer, Heidelberg (2006)Ricci, A., Omicini, A., Viroli, M., Gardelli, L., Oliva, E.: Cognitive stigmergy: towards a framework based on agents and artifacts. In: Weyns, D., Van Dyke Parunak, H., Michel, F. (eds.) E4MAS 2006. LNCS (LNAI), vol. 4389, pp. 124–140. Springer, Heidelberg (2007)Ricci, A., Piunti, M., Viroli, M.: Environment programming in multi-agent systems: an artifact-based perspective. Auton. Agent. Multi-Agent Syst. 23(2), 158–192 (2011)Ricci, A., Viroli, M., Omicini, A.: Environment-based coordination through coordination artifacts. In: Weyns, D., Van Dyke Parunak, H., Michel, F. (eds.) E4MAS 2004. LNCS (LNAI), vol. 3374, pp. 190–214. Springer, Heidelberg (2005)Ricci, A., Viroli, M., Omicini, A.: $${\sf CArtA gO}$$ : a framework for prototyping artifact-based environments in MAS. In: Weyns, D., Van Dyke Parunak, H., Michel, F. (eds.) E4MAS 2006. LNCS (LNAI), vol. 4389, pp. 67–86. Springer, Heidelberg (2007)Rincon, J.A., Garcia, E., Julian, V., Carrascosa, C.: Developing adaptive agents situated in intelligent virtual environments. In: Polycarpou, M., de Carvalho, A.C.P.L.F., Pan, J.-S., Woźniak, M., Quintian, H., Corchado, E. (eds.) HAIS 2014. LNCS, vol. 8480, pp. 98–109. Springer, Heidelberg (2014)Saunier, J., Balbo, F., Pinson, S.: A formal model of communication and context awareness in multiagent systems. J. Logic Lang. Inform. 23(2), 219–247 (2014). http://dx.doi.org/10.1007/s10849-014-9198-8Saunier, J., Jones, H.: Mixed agent/social dynamics for emotion computation. In: Proceedings of the 2014 international conference on Autonomous agents and multi-agent systems, pp. 645–652. International Foundation for Autonomous Agents and Multiagent Systems (2014)Simonin, O., Ferber, J.: Modeling self satisfaction and altruism to handle action selection and reactive cooperation. In: 6th International Conference on the Simulation of Adaptive Behavior (SAB 2000 volume 2), pp. 314–323 (2000)Thalmann, D., Musse, S.R.: Crowd Simulation. Springer, London (2007)Thiebaux, M., Marsella, S., Marshall, A., Kallmann, M.: Smartbody: Behavior realization for embodied conversational agents. In: Proceedings of the 7th international joint conference on Autonomous agents and multiagent systems, vol. 1, pp. 151–158 (2008)Viroli, M., Holvoet, T., Ricci, A., Schelfthout, K., Zambonelli, F.: Infrastructures for the environment of multiagent system. Int. J. Auton. Agent. 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Studying Network Mechanisms Using Intracranial Stimulation in Epileptic Patients

Patients suffering from focal drug-resistant epilepsy who are explored using intracranial electrodes allow to obtain data of exceptional value for studying brain dynamics in correlation with pathophysiological and cognitive processes. Direct electrical stimulation (DES) of cortical regions and axonal tracts in those patients elicits a number of very specific perceptual or behavioral responses, but also abnormal responses due to specific configurations of epileptic networks. Here, we review how anatomo-functional brain connectivity and epilepsy network mechanisms can be assessed from DES responses measured in patients. After a brief summary of mechanisms of action of brain electrical stimulation, we recall the conceptual framework for interpreting DES results in the context of brain connectivity and review how DES can be used for the characterization of functional networks, the identification of the seizure onset zone, the study of brain plasticity mechanisms, and the anticipation of epileptic seizures. This pool of exceptional data may be underexploited by fundamental research on brain connectivity and leaves much to be learned

Maximum Independent Set when excluding an induced minor: K1+tK2K_1 + tK_2 and tC3⊎C4tC_3 \uplus C_4

Dallard, Milani\v{c}, and \v{S}torgel [arXiv '22] ask if for every class excluding a fixed planar graph $H$ as an induced minor, Maximum Independent Set can be solved in polynomial time, and show that this is indeed the case when $H$ is any planar complete bipartite graph, or the 5-vertex clique minus one edge, or minus two disjoint edges. A positive answer would constitute a far-reaching generalization of the state-of-the-art, when we currently do not know if a polynomial-time algorithm exists when $H$ is the 7-vertex path. Relaxing tractability to the existence of a quasipolynomial-time algorithm, we know substantially more. Indeed, quasipolynomial-time algorithms were recently obtained for the $t$-vertex cycle, $C_t$ [Gartland et al., STOC '21] and the disjoint union of $t$ triangles, $tC_3$ [Bonamy et al., SODA '23]. We give, for every integer $t$, a polynomial-time algorithm running in $n^{O(t^5)}$ when $H$ is the friendship graph $K_1 + tK_2$ ($t$ disjoint edges plus a vertex fully adjacent to them), and a quasipolynomial-time algorithm running in $n^{O(t^2 \log n)+t^{O(1)}}$ when $H$ is $tC_3 \uplus C_4$ (the disjoint union of $t$ triangles and a 4-vertex cycle). The former extends a classical result on graphs excluding $tK_2$ as an induced subgraph [Alekseev, DAM '07], while the latter extends Bonamy et al.'s result.Comment: 15 pages, 2 figure

A tamed family of triangle-free graphs with unbounded chromatic number

We construct a hereditary class of triangle-free graphs with unbounded chromatic number, in which every non-trivial graph either contains a pair of non-adjacent twins or has an edgeless vertex cutset of size at most two. This answers in the negative a question of Chudnovsky, Penev, Scott, and Trotignon. The class is the hereditary closure of a family of (triangle-free) twincut graphs $G_1, G_2, \ldots$ such that $G_k$ has chromatic number $k$. We also show that every twincut graph is edge-critical

Assessing the WiFi offloading benefit on both service performance and EMF exposure in urban areas

In this paper we assess the benefit of WiFi offloading over dense urban scenarios in terms of both Quality of Service (QoS) and Electromagnetic Field (EMF) exposure. This study relies on results obtained with two complementary simulation platforms: a two-tier dynamic system-level simulator and a 3D coverage-based simulator. Outputs are usual service coverage key performance indicators, handover probability statistics, as well as common and innovative metrics for EMF exposure characterization that jointly take into account the contributions from the base-station and the User-Equipment (UE) transmissions. The main outcome is that, for elastic services, the best QoS and minimum global EMF exposure are jointly achieved with maximum WiFi offloading.This paper reports work undertaken in the context of the FP7 project LEXNET (GA nº 318273). Ramón Agüero also acknowledges the Spanish Government for the project “Connectivity as a Service: Access for the Internet of the Future”, COSAIF (TEC2012-38574-C02-02)

Optimal dosimeter deployment into a smart city IoT platform for wideband EMF exposure assessment

LEXNET project, funded by the European Commission, is introducing new concepts for the assessment of the population EMF exposure. It also aims at evaluating the capability of future technologies to reduce this EMF exposure. The platform presented in this paper is an original tool for a continuous measurement of the multi-band downlink Electric Field strength at a scale of a city, relying on the SmartSantander sensor network that was developed in a previous project. The testbed integrates a new equipment to capture the E-field strength, i.e. connected dosimeters. The work that is reported here focuses on the deployment of those dosimeters in the city of Santander. The presented methodology uses both simulation and measurement to achieve an optimal design, i.e. a dosimeter deployment that provides relevant exposure statistics and allows for the creation of exposure maps. Results on the pre-deployment simulations are given in this document, while the complete design optimization will be demonstrated later in Year 2015