Year: 2020

CITI seminar – Mario Zanon (IMT Lucca) – 30/06 at 14:00

Title: Optimal Control, MPC, and Reinforcement Learning

Date and Place: 30 / 06 / 2020 14:00

Speaker: Mario Zanon (Assistant Professor, IMT Lucca, Italy)

Host: Maracas

 

Abstract: Data-driven control approaches such as Reinforcement Learning (RL) mitigate the issue of model construction and controller tuning by learning directly the (optimal) control law from data. While stunning results have been obtained, RL cannot provide stability nor safety guarantees. Additionally, while partial information on the system is usually available, it can be hard to use it within RL. Model Predictive Control (MPC) is an advanced control technique able to deal with nonlinear systems subject to constraints. The main idea of MPC is to use a mathematical model of the process to predict its future behavior and minimize a given performance index. The advantages of MPC are numerous, as it makes it relatively easy to handle various difficulties in control design, such as dealing with constraints, nonlinear and hybrid dynamics, etc. One of the main drawbacks of MPC is that control performance is highly dependent on the predictive ability of the model. In this seminar, we will discuss how RL and MPC can be combined with the aim of benefitting from the advantages of each while limiting the drawbacks of both. We will introduce the two techniques and present some recent theoretical results, supported by simulation results.

 

Biography:
Mario Zanon received the Master’s degree in Mechatronics from the University of Trento, and the Diplôme d’Ingénieur from the Ecole Centrale Paris, in 2010. After research stays at the KU Leuven, University of Bayreuth, Chalmers University, and the University of Freiburg he received the Ph.D. degree in Electrical Engineering from the KU Leuven in November 2015. He held a Post-Doc researcher position at Chalmers University until the end of 2017 and is now Assistant Professor at the IMT School for Advanced Studies Lucca. His research interests include numerical methods for optimization, economic MPC, reinforcement learning and optimal control and estimation of nonlinear dynamic systems, in particular for aerospace and automotive applications.

 


PhD Defence: “Autonomous Wireless Sensor Network Architecture for Vehicular traffic monitoring at an Intersection”, Domga Komguem, 6th of July 2020 at 10AM

The defense will take place at the University of Yaoundé I and will be available at https://join.skype.com/EVc3J1aGhASf

Title

Autonomous Wireless Sensor Network Architecture for Vehicular traffic monitoring at an Intersection

 

Abstract

In many countries, because of the limited financial budget, the growth of road infrastructures is low compared to the growth of population and the number of vehicles in urban areas. Such a context does not make the task easy for authorities in charge of the management of transportation systems. The introduction of information and communication technologies (ICT) allows to better address these issues. Vehicular traffic management at intersections has an impact on the traffic jam observed in the whole city. In this thesis, our goal is to propose a low-cost, lightweight and autonomous Wireless Sensors Network (WSN) architecture for vehicular traffic monitoring, especially at an intersection. Vehicular traffic data collected can be used, for instance, for intelligent traffic lights management. In the WSN architecture proposed in the literature for vehicular traffic monitoring, underground sensors are used. In terms of network communication, these architectures are not realistic. Nowadays, surface-mounted sensors are proposed by manufacturers.

The first contribution of this thesis is an experimental characterization of wireless links in a WSN with sensors deployed at the ground level. We evaluate the impact of several parameters like the proximity of the ground surface, the communication frequency and the message size on the link quality. Results show a poor link quality at ground level. Based on the conclusions of the experiments, the second contribution of this thesis is WARIM, a new WSN architecture for vehicular traffic monitoring at an intersection. In WARIM, the sensors deployed on a lane form a multi-hop WSN with a linear topology (LWSN). In this network, all the data are forwarded toward the sink. In a network with such properties, the computation and communication requirements are highest in the neighborhood of the sink. Thus, the third contribution of this thesis is a virtual nodes-based and energy efficient sensors deployment strategy for LWSN. Compared to a uniform deployment, this deployment improves the network lifetime by 40%. In our intersection monitoring application, it is important to correlate the messages generated by a sensor to its position with respect to the intersection. Therefore,the fourth contribution of this thesis is, a centroid-based algorithm for sensors ranking in a LWSN. We evaluate the performance of this algorithm considering a realistic channel model, a uniform deployment, as well as the virtual nodes based-deployment proposed in this thesis. Finally, putting all our contributions together, simulations show that WARIM can be used for reliable and real-time vehicular traffic monitoring at an intersection.

 

Jury

  • Marcel FOUDA, Professor, Université de Yaoundé I, President
  • Thomas DJOTIO, Associate Professor, Université de Yaoundé I, Reviewer
  • Nathalie MITTON, Research Director, INRIA, Reviewer
  • Bernard TOURANCHEAU, Professor, Université Grenoble Alpes, Reviewer
  • André-Luc BEYLOT, Professor, ENSEEIHT Toulouse, Examinator
  • René NDOUNDAM, Associate Professor, Université de Yaoundé I, Examinator
  • Razvan STANICA, HDR, INSA Lyon, Examinator
  • Maurice TCHUENTE, Professor, Université de Yaoundé I, Co-Supervisor
  • Fabrice VALOIS, Professor, INSA Lyon, Co-Supervisor

CITI seminar – Ioannis Krikidis (Univ. Cyprus) – 13/02 at 11:30

Title: Wireless Powered Communications: Overview, Recent Results, and Challenges

Date and Place: 13 / 02 / 2020 10:30 in TD-C

Speaker: Ioannis Krikidis (Univ. Cyprus)

Host: Maracas

 

Abstract:
Conventional energy-constrained wireless systems such as sensor networks are powered by batteries and have limited lifetime. Wireless power transfer (WPT) is a promising technology for energy sustainable networks, where terminals can harvest energy from dedicated electromagnetic radiation through appropriate electronic circuits. The integration of WPT technology into communication networks introduces a fundamental co-existence of information and energy flows; radio-frequency signals are used in order to convey information and/or energy. The efficient management of these two flows through sophisticated networking protocols, signal processing/communication techniques and network architectures, gives rise to a new communication paradigm called wireless powered communications (WPC). In this talk, we discuss the principles of WPC and we highlight its main network architectures as well as the fundamental trade-off between information and energy transfer. Several examples, which deal with the integration of WPC in modern communication systems, are presented.

 

Biography:
Dr. Ioannis Krikidis received the diploma in Computer Engineering from the Computer Engineering and Informatics Department (CEID) of the University of Patras, Greece, in 2000, and the M.Sc and Ph.D degrees from Ecole Nationale Superieure des Telecommunications (ENST), Paris, France, in 2001 and 2005, respectively, all in electrical engineering. From 2006 to 2007 he worked, as a Post-Doctoral researcher, with ENST, Paris, France, and from 2007 to 2010 he was a Research Fellow in the School of Engineering and Electronics at the University of Edinburgh, Edinburgh, UK. He is currently an Associate Professor at the Department of Electrical and Computer Engineering, University of Cyprus, Nicosia, Cyprus. His current research interests include wireless communications, cooperative networks, 4G/5G communication systems, wireless powered communications, and secrecy communications. I. Krikidis is an IEEE Fellow (class 2019) and he has received the prestigious ERC consolidator grant.

 


CITI seminar – Mari Kobayashi (TU Munich) – 13/02 at 10:30

Title: Joint State Sending and Communications: Theory and Vehicular Applications

Date and Place: 13 / 02 / 2020 10:30 in TD-C

Speaker: Mari Kobayashi (TU Munich)

Host: Maracas

 

Abstract:
We consider a communication setup where transmitters wish to simultaneously sense network states and convey messages to intended receivers. The scenario is motivated by joint radar and vehicular communications where the radar and data applications share the same bandwidth. First, I present a theoretical framework to characterize the fundamental limits of such a setup for memoryless channels with i.i.d. state sequences. Then, I present our recent work on joint radar and communication using Orthogonal Time Frequency Space (OTFS). Although restricted to a simplified scenario with a single target, our numerical examples demonstrated that two modulations provide as accurate radar estimation as Frequency Modulated Continuous Waveform (FMCW), a typical automotive radar waveform, while providing a non-negligible communication rate for free.

 

Biography:
Mari Kobayashi received the B.E. degree in electrical engineering from Keio University, Yokohama, Japan, in 1999, and the M.S. degree in mobile radio and the Ph.D. degree from École Nationale Supérieure des Télécommunications, Paris, France, in 2000 and 2005, respectively. From November 2005 to March 2007, she was a postdoctoral researcher at the Centre Tecnològic de Telecomunicacions de Catalunya, Barcelona, Spain. In May 2007, she joined the Telecommunications department at CentraleSupélec, Gif-sur-Yvette, France, where she is now a professor. She is the recipient of the Newcom++ Best Paper Award in 2010, and IEEE Comsoc/IT Joint Society Paper Award in 2011, and ICC Best Paper Award in 2019. Since September 2017, she is on a sabbatical leave at Technical University of Munich (TUM) as an Alexander von Humboldt Experienced Research Fellow (till April 2019) and August-Wihelm Scheer Visiting Professor (since August 2019).

 


PhD Defence: “Simultaneous Information and Energy Transmission”, Nizar Khalfet, Emilie du Chatelet Amphitheater, INSA, 13th of February 2020 at 14h

Title

Simultaneous Information and Energy Transmission

Abstract

In this thesis, the fundamental limits of simultaneous information and energy transmission (SIET) are studied from two perspectives: the asymptotic and non-asymptotic block-length regimes. In the asymptotic block-length regime, the fundamental limits on SIET in the two-user Gaussian interference channel (G-IC) with and without feedback are characterized. More specifically, an achievable and converse region in terms of information and energy transmission rates (in bits per channel use and energy-units per channel use, respectively) are identified. In both cases, with and without feedback, an achievability scheme based on power-splitting, common randomness, rate splitting, block-Markov superposition coding, and backward decoding is presented. Finally, converse regions for both cases are obtained using some of the existing outer bounds on information transmission rates, as well as a new outer bound on the energy transmission rate. For the finite block-length regime, the case of a transmitter simultaneously sending information to a receiver and energy to an energy harvester through the binary symmetric channel has been studied. Given a finite number of channel uses (latency constraint) as well as tolerable average decoding error probability and energy shortage probability (reliability constraints), two sets of information and energy

transmission rates are presented. One consists in rate pairs for which the existence of at least one code achieving such rates under the latency and reliability constraints is proved (achievable region). The second one consists in a set whose complement contains the rate pairs for which there does not exist a code capable of achieving such rates (converse region). These two sets approximate the information-energy capacity region, which allows analyzing the trade-offs among performance, latency, and reliability in SIET systems.

 

 

Jury

  • Dr. Samson Lasaulce, CNRS, France. Reviewer.
  • Dr. Ioannis Krikidis, University of Cyprus, Cyprus. Reviewer.
  • Dr. Marie Kobayashi, CentraleSupelec, France. Examiner.
  • Dr. Jean-Marie Gorce, INSA de Lyon, France. Supervisor.
  • Dr. Samir M. Perlaza, INRIA, France. Advisor.

CITI seminar – Xavier BULTEL (INSA CVL) – 30/01 at 11:00

Title: Sécurité des protocoles de jeux de levées : comment jouer au Bridge avec des tricheurs.

Date and Place: 30 / 01 / 2020 11:00 in TD-C

Speaker: Xavier Bultel (INSA CVL)

Host: Privatics

Abstract:
Les jeux de levées sont des jeux de cartes où chacun des joueurs pose une carte à tour de rôle en fonction d’une règle donnée. Le joueur qui a posé la carte la plus forte gagne la levée, c’est-à-dire toutes les cartes jouées durant la manche. Par exemple, Atout Pique est un jeu de levée très populaire sur les sites de casino en ligne, où chacun des joueurs doit, s’il le peut, jouer une carte de la même couleur que celle de la première carte de la manche. Dans ce genre de jeux, un joueur malhonnête peut jouer une mauvaise carte même s’il à des cartes de la bonne couleur. Comme les autres cartes sont cachées, il est impossible de détecter la triche. Les autres joueurs s’en rendront compte plus tard, lorsque le tricheur jouera une carte qu’il n’est pas sensé avoir. Dans ce cas, le jeu est biaisé et doit être annulé, et l’équipe qui a triché se voit attribuer une pénalité de paiement. cela pose problème si le partenaire du tricheur n’est pas son complice, ce qui est le cas dans les jeux en ligne puisque les joueurs sont appareillés par le serveur du site. Notre but est de proposer un protocole cryptographique qui prévient ce genre de triche. Dans ce tte présentation on définit d’abord un modèle de sécurité pour les protocoles d’Atout Pique sécurisés, puis on construit un protocole appelé SecureSpades. Ce protocole est prouvé sûr dans notre modèle sous l’hypothèse Diffie-Hellman Décisionnel, dans le modèle de l’oracle aléatoire. Notre modèle de sécurité et notre protocole peuvent être étendus à un grand nombre d’autres jeux de levées, comme la Belotte, le Bridge, le Whist, etc.

Biography:
Xavier Bultel, MdC à l’INSA CVL depuis septembre 2019 ; Ex Postdoc à l’IRISA à Rennes (2018-2019) et doctorant au LIMOS à Clermont-Ferrand sous la direction de Pascal Lafourcade (2014-2018).


CITI seminar – Julien Bourgeois (Univ. Bourgogne-Franche-Comté, Institut FEMTO-ST, CNRS) – 23/01 at 14:00

Title: Building programmable matter with micro-robots

Date and Place: 23 / 01 / 2020 14:00 in TD-C

Speaker: Julien Bourgeois (Univ. Bourgogne-Franche-Comté, Institut FEMTO-ST, CNRS)

Host: Olivier Simonin

Abstract:
Technological advances, especially in the miniaturization of robotic devices foreshadow the emergence of large-scale ensembles of small-size resource-constrained robots that distributively cooperate to achieve complex tasks. These ensembles are formed by independent, intelligent and communicating units which act as a whole ensemble which can be used to build programmable matter i.e. matter able to change its shape.
In my talk, I will present our research effort in building Programmable Matter (PM) based on modular robots. To do this, we use micro-technology to scale down the size of each element, and we study geometry, structure, actuation, power, electronics and integration. To manage the complexity of this kind of environment, we propose a complete environment including programmable hardware, a programming language, a compiler, a simulator, a debugger and distributed algorithms.

Biography:
Julien Bourgeois is a professor of computer science at the University of Bourgogne Franche-Comté (UBFC) in France. He is leading the computer science department at the FEMTO-ST institute/CNRS. His research interests include distributed intelligent MEMS (DiMEMS), Programmable Matter, P2P networks and security management for complex networks. He has worked for more than 15 years on these topics and has co-authored more than 160 international publications. He was an invited professor at Carnegie Mellon University (US) from 2012 to 2013, at Emory University (US) in 2011 and at Hong Kong Polytechnic University in 2010, 2011 and 2015. He led different funded research projects (Smart Surface, Smart Blocks, Computation and coordination for DiMEMS). He is currently leading the programmable matter project funded by the ANR and the ISITE-BFC project. He organized and chaired many conferences (dMEMS 2010, 2012, HotP2P/IPDPS 2010, Euromicro PDP 2008 and 2010, IEEE GreenCom 2012, IEEE iThings 2012, IEEE CPSCom 2012, GPC 2012, IEEE HPCC 2014, IEEE ICESS 2014, CSS 2014, IEEE CSE 2016, IEEE EUC 2015, IEEE ATC 2017, IEEE CBDCom 2017).