S³: Gegenbauer polynomials and positive definiteness

Séminaire le 27 Novembre 2015, 10h30 à CentraleSupelec (Gif-sur-Yvette) Salle des séminaires du L2S
Christian Berg, University of Copenhagen, Denmark


Abstract file

Bio: Professor Christian Berg graduated from Næstved Gymnasium 1963 and studied mathematics at the University of Copenhagen. He became cand.scient. in 1968, lic.scient. (ph.d.) in 1971, and dr. phil. in 1976. Christian Berg received the gold medal of the University of Copenhagen in 1969 for a paper about Potential Theory.
He became assistant professor at University of Copenhagen in 1971, associated professor in 1972 and professor since 1978. Christian Berg had several research visits abroad, in USA, France, Spain, Sweden and Poland.
He became member of The Royal Danish Academy of Sciences and Letters 1982, vice-president 1999-2005. Member of The Danish Natural Sciences Research Council 1985-1992. President of the Danish Mathematical Society 1994-98. Member of the editorial board of Journal of Theoretical Probability (1988-1999) and Expositiones Mathematicae since 1993. Member of the advisory board of Arab Journal of Mathematical Sciences since 1995.
At the Department of Mathematics of the University of Copenhagen, he was Member of the Study Board 1972-74, member of the Board 1977-1984, 1993-1995, chairman 1996-97, and Director of the Institute for Mathematical Sciences 1997-2002.
Christian Berg  has so far published app. 110 scientific papers in international journals, mainly about potential theory, harmonic analysis and moment problems.

S³:Bayesian Fusion of Multiple Images - Beyond Pansharpening

Séminaire le 13 Novembre 2015, 10h30 à CentraleSupelec (Gif-sur-Yvette) Salle des séminaires du L2S
Jean-Yves Tourneret, University of Toulouse, FR


This presentation will discuss new methods for fusing high spectral resolution images (such as hyperspectral images) and high spatial resolution images (such as panchromatic images) in order to provide images with improved spectral and spatial resolutions. These methods are based on Bayesian estimators exploiting prior information about the target image to be recovered, constructed by interpolation or by using dictionary learning techniques. Different implementations based on MCMC methods, optimization strategies or on the resolution of Sylvester equations will be explored

Bio: Jean-Yves TOURNERET (SM08) received the ingenieur degree in electrical engineering from the Ecole Nationale Supérieure d'Electronique, d'Electrotechnique, d'Informatique, d'Hydraulique et des Télécommunications (ENSEEIHT) de Toulouse in 1989 and the Ph.D. degree from the National Polytechnic Institute from Toulouse in 1992. He is currently a professor in the university of Toulouse (ENSEEIHT) and a member of the IRIT laboratory (UMR 5505 of the CNRS). His research activities are centered around statistical signal and image processing with a particular interest to Bayesian and Markov chain Monte Carlo (MCMC) methods. He has been involved in the organization of several conferences including the European conference on signal processing EUSIPCO'02 (program chair), the international conference ICASSP'06 (plenaries), the statistical signal processing workshop SSP'12 (international liaisons), the International Workshop on Computational Advances in Multi-Sensor Adaptive Processing CAMSAP 2013 (local arrangements), the statistical signal processing workshop SSP'2014 (special sessions), the workshop on machine learning for signal processing MLSP'2014 (special sessions). He has been the general chair of the CIMI workshop on optimization and statistics in image processing hold in Toulouse in 2013 (with F. Malgouyres and D. Kouamé) and of the International Workshop on Computational Advances in Multi-Sensor Adaptive Processing CAMSAP 2015 (with P. Djuric). He has been a member of different technical committees including the Signal Processing Theory and Methods (SPTM) committee of the IEEE Signal Processing Society (2001-2007, 2010-present). He has been serving as an associate editor for the IEEE Transactions on Signal Processing (2008-2011, 2015-present) and for the EURASIP journal on Signal Processing (2013-present).

Access information are available on the website http://www.lss.supelec.fr/scube/

S³: Algorithmes d’Estimation et de Détection en contexte Hétérogène Rang Faible

Séminaire le 6 Novembre 2015, 10h30 à CentraleSupelec (Gif-sur-Yvette) Salle des séminaires du L2S
A. Breloy, Ecole Normale Supérieure de Cachan, FR


Covariance Matrix (CM) estimation is an ubiquitous problem in statistical signal processing. In terms of application purposes, the accuracy of the CM estimate directly impacts the performance of the considered adaptive process. In the context of modern data-sets, two major problems are currently at stake:

- Samples are often drawn from heterogeneous (non gaussian) distributions.
- Only a low sample support is available.

To respond to these problems, one has to develop new estimation tools that are based on an appropriate modeling of the data.

Bio: Arnaud Breloy graduated from Ecole Centrale Marseille and recived a Master's degree of Signal and Image Processing from university of Aix-Marseille in 2012-13. Formerly Ph.D student at the SATIE and SONDRA laboratories, he is currently lecturer at University Institute of Technology of Ville d’Avray. His research interests focuses on statistical signal processing, array and radar signal processing, robust estimation methods and low rank methods.

Mismatched decoding

Séminaire le 22 Octobre 2015, 11h00 à CentraleSupelec (Gif-sur-Yvette) Salle du conseil du L2S - B4.40
Dr. Guillen i Fabregas


This talk will review the mismatched decoding problem. In particular, the talk will review the fundamental limits of mismatched channel-decoder pairs in a point-to-point setup, with particular focus on random coding ensembles, achievable information rates and the corresponding error exponents.

Bio:
Albert Guillén i Fàbregas was born in Barcelona in 1974. In 1999 he received the Telecommunication Engineering Degree and the Electronics Engineering Degree from Universitat Politècnica de Catalunya and Politecnico di Torino, respectively, and the Ph.D. in Communication Systems from Ecole Polytechnique Fédérale de Lausanne (EPFL) in 2004.
Since 2011 he has been a Research Professor of the Institució Catalana de Recerca i Estudis Avançats (ICREA) at the Department of Information and Communication Technologies,
Universitat Pompeu Fabra. He is also an Adjunct Researcher at the Department of Engineering, University of Cambridge, where he was a Reader and a Fellow of Trinity Hall. He has held appoinments at the New Jersey Institute of Technology, Telecom Italia, European Space Agency (ESA), Institut Eurecom, University of South Australia, as well as visiting appointments at TelecomParisTech (Paris), Universitat Pompeu Fabra, University of South Australia, Centrum Wiskunde & Informatica and Texas A&M University in Qatar. His research interests are in information theory, coding theory and communication theory. Dr. Guillén i Fàbregas received the Starting Grant from the European Research Council, the Young Authors Award of the 2004 European Signal Processing Conference, the 2004 Best Doctoral Thesis Award from the Spanish Institution of Telecommunications Engineers, and a Research Fellowship of the Spanish Government to join ESA. He is an Associate Editor of the IEEE Transactions on Information Theory and of the Foundations and Trends in Communications and Information Theory, Now Publishers. He is also a Senior Member of IEEE,  a member of theYoung Academy of Europe and was an Editor of the IEEE Transactions on Wireless Communications (2007-2011).

Pseudorational transfer functions and their spectral properties - an introductory survey

Séminaire le 15 Octobre 2015, 14h30 à CentraleSupelec (Gif-sur-Yvette) Salle du conseil du L2S - B4.40
Yutaka Yamamoto, univ of Kyoto


This talk gives an overview of the class of pseudorational transfer functions. This class consists of the ratio of entire functions of exponential type that are Laplace transforms of distributions with compact support. It gives rise to a convenient platform for dealing with distributed parameter systems whose state space is determined by bounded-time data.  Delay-differential systems, with retarded, neutral or distributed delays, are typical examples. We explore its interesting interplay with the ring of entire functions, and highlight some appealing structures as follows: Starting from a completely general input/output framework, we derive a concrete realization procedure based on the above fractional representation of transfer functions (or impulse responses).  It is then also possible to give a complete characterization of spectral properties of such realizations via zeros of the denominator of transfer functions.
Such spectral properties allow us to give a stability criterion and also an appropriate relationship between internal and external stability notions. Based on a concrete representation of the state space, we are led to a concrete characterization of left-shift invariant subspaces of H^2.  This result has a direct consequence on H-infinity control theory.
We also give a concise yet comprehensive and unified overview of such results.  The talk is concluded with this and also a criterion on the existence of a Bezout identity in this class.

Fronthaul Compression for Cloud Radio Access Networks: An Information Theoretic View

Séminaire le 28 Septembre 2015, 14h00 à CentraleSupelec (Gif-sur-Yvette) Amphi F3-09
Prof. Shlomo Shamai, EE Department, Technion-Israel Institute of Technology


Cloud radio access networks (C-RANs) emerge as appealing architectures for next-generation wireless/cellular systems whereby the processing/decoding is migrated from the local base-stations/radio units (RU) to a control/central units (CU) in the *cloud*. This is facilitated by fronthaul links connecting the RUs to the managing CUs. We focus on oblivious processing at the RU, and hence the fronthaul links carry digital information about the baseband signals, in the uplink from the RUs to the CU and vice versa in the downlink. The high data rate service demands in C-RANs, imply that even with fast (optical) front hauls, let alone for heterogeneous fronhauls, efficient compression of the basedand signals is essential. In this talk we focus on advanced robust signal processing solutions, emerging by network information theoretic concepts, and review also the basic approaches to this cloud network. Multi-hop fronthaul topologies are also discussed. Analysis and numerical results illustrate the considerable performance gains to be expected for different cellular models. Some interesting theoretical directions conclude the presentation.

S³: Bayesian Tomography

Séminaire le 25 Septembre 2015, 10h30 à CentraleSupelec (Gif-sur-Yvette) Salle du conseil du L2S - B4.40
John Skilling, Maximum Entropy Data Consultants Ltd, UK


Abstract: Click here

Bio: John Skilling was awarded his PhD in radio astronomy in 1969.  Through the 1970s and 1980s he was a lecturer in applied mathematics at Cambridge University, specialising in data analysis.  He left to concentrate on consultancy work, originally using maximum entropy methods but moving to Bayesian methodology when algorithms became sufficiently powerful.  John has been a prominent contributor to the “MaxEnt” conferences since their beginning in 1981.  He is the discoverer of the nested sampling algorithm which performs integration over spaces of arbitrary dimension, which is the basic operation dictated by the sum rule of Bayesian calculus.

S³: Is the Gaussian distribution "Normal"? Signal processing with alpha-stable distributions

Séminaire le 18 Septembre 2015, 10h30 à CentraleSupelec (Gif-sur-Yvette) Salle des séminaires du L2S
Ecran E. Kuruoglu, Istituto di Scienza e Tecnologie dell'Informazione, Italy


There are solid reasons for the popularity of Gaussian models. They are easy to deal with, lead to linear equations, and they have a strong theoretical justification given by the Central Limit theorem. However, many data, manmade or natural, exhibit characteristics too impulsive or skewed to be successfully accommodated by the Gaussian model. The wide spread power laws in the nature, in internet, in linguistics, biology are very well known. In this talk we will challengethe "Normality" of the Gaussian distribution and will discuss the alpha‐stable distribution family which satisfies the generalised Central Limit Theorem. Alpha‐Stable distributions have received wide interest in the signal processing community and became state of the art models for impulsive noise and internet traffic in the last 20 years since the influential paper of Nikias and Shao in 1993. We will provide the fundamental theory and discuss the rich class of statistics this family enables us to work with including fractional order statistics, log statistics and extreme value statistics. We will present some application areas where alpha‐stable distributions had important success such as internet traffic modelling, SAR imaging, computational biology, astronomy, etc. We will also present recent research results on generalisation of source separation algorithms by maximizing non-alpha stability and also multivariate analysis using alpha-stable Bayesian networks. We will identify open problems which we hope will lead to fruitful discussion on further research on this family of distributions.

Bio: Ercan E. Kuruoglu was born in Ankara, Turkey in 1969. He obtained his BSc and MSc degrees both in Electrical and Electronics  Engineering  at  Bilkent  University  in  1991  and  1993  and  the  MPhil  and  PhD  degrees  in  Information  Engineering  at  the Cambridge University, in the Signal Processing Laboratory, in 1995 and 1998 respectively. Upon graduation from Cambridge, he joined the Xerox Research Center in Cambridge as a permanent member of theCollaborative Multimedia Systems Group. In 2000, he was in INRIA‐Sophia Antipolis as an ERCIM fellow. In 2002, he joined ISTI‐CNR, Pisa as a permanent member. Since 2006, he  is  an Associate Professor  and  Senior Researcher. He was  a  visiting professor  in Georgia Institute of Technology graduate  program  in  Shanghai  in  2007  and  2011. He was a 111 Project (Bringing Foreign Experts to China Program) Fellow and was a frequent visitor to Shanghai Jiao Tong University, China (2007‐2011). He was an Visiting Professor in Hong Kong, in August 2012 as a guest of the HK IEEE Chapter. He is a recipient of the Alexander von Humboldt Foundation Fellowship (2012‐2014) which allowed him to work in as a visiting scientist at Max‐Planck Institute for Molecular Biology. He was an Associate Editor for IEEE Transactions on Signal Processing in 2002‐2006 and for IEEE Transactions on Image Processing in 2005‐2009. He is currently the Editor in Chief of Digital Signal Processing: a Review Journal and also is in the editorial board of EURASIP Journal on Advances in Signal Processing. He was the Technical co‐Chair for EUSIPCO 2006, special sessions chair of EUSIPCO 2005 and tutorials  co‐chair of ICASSP 2014. He served  as  an  elected member of the IEEE  Technical Committee on  Signal Processing Theory and Methods (2004‐2010), was a member of IEEE Ethics committee in 2012 and is a Senior Member of IEEE. He was a plenary speaker at Data Analysis for Cosmology (DAC 2007) and ISSPA 2010 and tutorial speaker at ICSPCC 2012 and Bioinformatiha 2013 and 2014 . He is the author of more than 100 peer reviewed publications and holds 5 US, European and Japanese patents. His research interests  are  in  statistical  signal  processing  and  information  and  coding  theory  with  applications  in  image  processing, computational biology, telecommunications, astronomy and geophysics.

 

Access information are available on the website http://www.lss.supelec.fr/scube/

 

A sparsity-promoting reconstruction algorithm for diffuse optical tomography based on a transport model

Séminaire le 8 Septembre 2015, 11h30 à CentraleSupelec (Gif-sur-Yvette) Salle du conseil du L2S - B4.40
K. Prieto (formerly University of Manchester, since Aug 2015 Hokkaido University) and O. Dorn (University of Manchester) (presenting author)


Non-linear inverse problems with sparsity

Séminaire le 8 Septembre 2015, 10h30 à CentraleSupelec (Gif-sur-Yvette) Salle du conseil du L2S - B4.40
P. Maass (University of Bremen)


Compressive Sensing as a tool for exploiting sparsity and incoherence in computational electromagnetics

Séminaire le 8 Septembre 2015, 09h30 à CentraleSupelec (Gif-sur-Yvette) Salle du conseil du L2S - B4.40
A. Massa (presenting author), G. Oliveri, M. Salucci, N. Anselmi (all at ELEDIA, University of Trento, A. Massa as DIGITEO Chair holder L2S & CEA LIST)


S³: Bayesian Cyclic Networks, Mutual Information and Reduced-Order Bayesian Inference

Séminaire le 17 Juillet 2015, 10h30 à CentraleSupelec (Gif-sur-Yvette) Salle des séminaires du L2S
Robert Niven, University of New South Wales, Canberra, Australia


A branch of Bayesian inference involves the analysis of so-called "Bayesian networks", defined as directed acyclic networks composed of probabilistic connections. We extend this class of networks to consider cyclic Bayesian networks, which incorporate every pair of inverse conditional probabilities or probability density functions, thereby enabling the application of Bayesian updating around the network. The networks are assumed Markovian, although this assumption can be relaxed when necessary. The analysis of probabilistic cycles reveals a deep connection to the mutual information between pairs of variables on the network. Analysis of a four-parameter network - of the form of a commutative diagram - is shown to enable thedevelopment of a new branch of Bayesian inference using a reduced order model (coarse-graining) framework.

Bio: https://research.unsw.edu.au/people/dr-robert-niven

S³: The method of brackets

Séminaire le 3 Juillet 2015, 10h30 à CentraleSupelec (Gif-sur-Yvette) Salle du conseil du L2S - B4.40
Victor H. Moll, Department of Mathematics, Tulane University, New Orleans, USA


A new heuristic method for the evaluation of denite integrals is presented. This method of brackets has its origin in methods developed for the evaluation of Feynman diagrams. We describe the operational rules and illustrate the method with several examples. The method of brackets reduces the evaluation of a large class of denite integrals to the solution of a linear system of equations.

Bio: Victor H. Moll studied under Henry McKean at the Courant Institute, graduated in 1984 with a thesis on the Stabilization of the standing wave in a caricature for nerve conduction. This so-called caricature had been proposed by McKean as a simpler model from the classical Nagumo and Hodgkin-Huxley models. After graduation, he spent two years as a Lawton instructor at Temple University. In 1986 he moved to Tulane University, New Orleans, where he is now a Professor of Mathematics.
He is interested in all aspects of the mathematics coming from the evaluation of integrals. The subject is full of interesting problems that he shares with colleagues, graduate and undergraduate students. Among the variety of results that have come out of this work, one should mention the theory of Landen transformations that are the rational version of the well-known transformations of Landen and Gauss for
elliptic integrals. His long term project is to provide proofs, automatic and human of all entries
in the classical table of Integrals by I. S. Gradshteyn and I. M. Ryzhik. Most of his work comes from exploring, via symbolic languages, unexpected relations among classical objects. Some of his work has been written in the book Numbers and Functions published in the Student Mathematical Library series from AMS. He is actively involved with bringing undergraduates into Mathematics. He has guided undergraduate research at Tulane University and also was the research leader at the REU programs SIMU (at the University of Puerto Rico at Humacao 2000 and 2002) and at MSRI-UP, Berkeley (2008 and 2014). A large number of his students have continued to graduate school in Mathematics.

Dynamics and Control of Inverted Ultra-Flexible Pendulum on Cart System

Séminaire le 29 Juin 2015, 16h00 à CentraleSupelec (Gif-sur-Yvette) Amphi Blondel
Prof. Prasanna S. Gandhi


Ultra-flexible beams are useful in several flexible mechanisms having applications, for example, in high-precision positioning systems and flexible link robotic systems. They demonstrate interesting dynamics, especially when these systems are in a vertical plane. This talk focuses on a representative of such system: a vertical, large-deformation cantilever with tip mass and actuated at fixed base by a cart. The system is shown to demonstrate multiple equilibria as a function of tip mass using elastica theory. Dynamics of this system is further captured using assumed modes method and imposing length constraint to model potential energy change of tip mass (constrained Langrange formulation). Evolution of chaotic behaviour under harmonic excitation is presented in comparison with experiments. We further develop a nonlinear nested saturations based controller for stabilising the cantilever in central unstable equilibrium with cart also reaching the desired position. Multiple coordinate transformations are performed to obtain a system in feedforward chain of integrators before applying nested saturation based control. Effectiveness of control is established through simulation cases and experimental implementation.

Biography: P.S. Gandhi received the B.Eng. degree in from the University of Bombay, Mumbai in 1994 and the M.Tech degree from the Indian Institute of Technology, Bombay, Mumbai in 1996, both in mechanical engineering. He received the Ph.D. degree in mechanical engineering from the Rice University, Houston in 2001. Since 2001, he has been faculty member, currently Professor, in the Department of Mechanical Engineering at Indian Institute of Technology, Bombay, Mumbai. His research interests are in the areas of MEMS and Microsystems, Mechatronics, and Nonlinear Dynamical Systems and Control. He has been a recipient of 2006 BOYSCAST fellowship of Govt of India, 2007 Best faculty award (ME department) and Prof J.R.Issac fellowship. He has authored several patents and over 85 peer reviewed conference and journal papers. He has coordinated setup of a new laboratory Suman Mashruwala Microengineering Laboratory for research in Microdomain and has successfully developed technologies of Bulk Lithography and Microstereolithography for 3D MEMS fabrication in this laboratory. He has been a qualified teacher of stress relieving, life enhancing techniques of Art of Living foundation by Sri Sri Ravishankar.

S³: Un modèle stochastique de la transcription d’un gène

Séminaire le 26 Juin 2015, 11h00 à CentraleSupelec (Gif-sur-Yvette) Salle des séminaires du L2S
Marc Roussel, University of Lethbridge, Alberta, Canada


Nous étudions depuis quelques années des modèles stochastiques de la transcription, c’est-à-dire de la synthèse de l’ARN à partir de la séquence de l’ADN par une machine moléculaire, l’ARN polymérase. Pour le cas d’une seule polymérase, il est possible de solutionner exactement nos modèles. Lorsque les interactions entre les polymérases sont importantes, il faut par contre utiliser (pour le moment) des méthodes numériques. En forme d’introduction au sujet, je présenterai un de nos modèles les plus simples, et je démontrerai comment on peut obtenir tous les moments voulus de la distribution du temps de transcription, c’est-à-dire comment on peut solutionner ce modèle. Cette distribution pourra être utilisée dans des modèles d’expression génétique, où elle apparaitra comme distribution de retards de la production de l’ARN.

Bio: Marc R. Roussel is Professor at Alberta RNA Research and Training Institute, Department of Chemistry and Biochemistry, University of Lethbridge. More details can be found at his homepage http://people.uleth.ca/~roussel/

S³: High dimensional minimum risk portfolio optimization

Séminaire le 26 Juin 2015, 10h00 à CentraleSupelec (Gif-sur-Yvette) Salle des séminaires du L2S
Liusha Yang, Department of Electronic and Computer Engineering, Hong Kong University of Science and Technology


The performance of the global minimum risk portfolio (GMVP) relies on the accuracy of the estimated covariance matrix of the portfolio asset returns. For large portfolios, the number of available market returns is often of similar order to the number of assets, making the sample covariance matrix performs poorly. In this talk, we discuss two newly-developed GMVP optimization strategies under high dimensional analysis. The first approach is based on the shrinkage Tyler’s robust M-estimation with a risk-minimizing shrinkage parameter. It not only deals with the problem of sample insufficiency, but also the impulsiveness of financial data. The second approach is built upon a spiked covariance model, by assuming the population covariance matrix follows the spiked covariance model, in which several eigenvalues are significantly larger than all the others, which all equal one. The performances of our strategies will be demonstrated through synthetic and real data simulations.

Bio: Liusha Yang received the B.S. in Communication Engineering from the Beijing University of Posts and Telecommunications in 2012. Currently, she is a Ph.D. student in the Department of Electronic and Computer Engineering at the Hong Kong University of Science and Technology. Her research interests include random matrix theory and signal processing, with applications in financial engineering.

Wireless devices and services for distributed sensing, monitoring, and decision support

Séminaire le 25 Juin 2015, 10h00 à CentraleSupelec (Gif-sur-Yvette) Salle du conseil du L2S - B4.40
F. Viani: "Research Associate" et membre du Centre de Recherche ELEDIA de l'université TRENTO


Low-power and compact wireless devices, like smart sensors, embedded systems, smartphones, tablets are more and more becoming everyday life tools, bringing advantages not limited to the mobile communications but also referred to improved context awareness. The potentialities of such wireless technologies are enriched by the integration of dedicated real-time processing techniques which enable not only the distributed sensing of heterogeneous parameters, but also the improved management, understanding, and forecasting of complex processes. The output of such analysis is also exploited to support operators in decision making. Representative application examples are in the field of smart cities and communities, where distributed wireless sensors and mobile devices are largely applied both in indoor (e.g., in smart buildings, smart museums, etc.) and outdoor (smart lighting, road security, fleet management, etc.) scenarios.

Short CV: Federico Viani received the B.S. and M.S. degrees in Telecommunication Engineering and  the PhD degree in Information and Communication Technology from the University of Trento, Italy, in 2004, 2007, and 2010, respectively. Since 2011, Dr. Viani is a Research Associate (Post-Doc) at the Department of Information Engineering and Computer Science (DISI) of the University of Trento, Italy, and a member of the ELEDIA Research Center.
Since 2007, Dr. Viani has been the co-advisor of 18 M.S/B.S Thesis. Since 2010 he has been the official teacher of the Bachelor degree course "Design Techniques for Wireless Communications", and since 2007 he has been a teaching assistant of Bachelor degree and Master degree courses in Telecommunication Engineering offered by the University of Trento, including "Electromagnetic Propagation", "Project Course on Wireless Technologies", "Antennas for Wireless Communications", "Biomedical Diagnostic Techniques", "Mobile Communications".
Dr. Viani is author/co-author of over 77 peer reviewed papers on international journals and conferences, including 28 contributions on peer-reviewed international journals, 49 in international conferences. Moreover, Dr. Viani has been cited 574 times and his H-Index is equal to 14 in the Scopus Database. He has been invited to submit papers to International Journals and to present contributions to Scientific Sessions in International Conferences. He has organized and/or chaired 3 Special Sessions in International Conferences. Since 2007, he has attended 7 national and international conferences, presenting as a speaker 15 contributions.
Since 2007, Dr. Viani has been a Participant in 17 Research Projects, funded by EU, Industries, and National Agencies.
The research activities of Dr. Viani are oriented to the development of methodological strategies and applications in the framework of Electromagnetic Fields (S.S.D. ING‐INF/02, S.C. 09/F1), with main emphasis on applied electromagnetics. He has been involved in activities concerning the design of multiband, wideband, and ultra-wideband antennas, the study and development of optimization techniques as well as learning-by-example methodologies for the solution of complex electromagnetic problems including inverse problems and active/passive wireless localization. He is also involved in the design and development of distributed and pervasive monitoring by means of wireless sensor networks (WSNs) and robot swarms, and in the application of decision support systems (DSS) to fleet management and emergency-related applications.
Dr. Viani is a Reviewer for international Journals, including IEEE Transactions on Antennas and Propagation, IEEE Antennas and Wireless Propagation Letters, Progress in Electromagnetic Research/Journal of Electromagnetic Waves and Applications, IEEE Transactions on Vehicular Technologies.
Dr. Viani is a Senior Member of the IEEE, member of the IEEE Antennas and Propagation Society, and of the European Microwave Association (EuMA).

S³: Stability of continuous-time quantum filters

Séminaire le 19 Juin 2015, 10h00 à CentraleSupelec (Gif-sur-Yvette) Salle des séminaires du L2S
Nina H. Amini, CNRS, Laboratory of Signals and Systems, France


In this talk, we study quantum filtering and its stability problem. Indeed, we show that the fidelity between the state of a continuously observed quantum system and the state of its associated quantum filter, is always a sub-martingale. The observed system could be governed by a continuous-time Stochastic Master Equation (SME), driven simultaneously by Wiener and Poisson processes which takes into account incompleteness and errors in measurements. This stability result is the continuous-time counterpart of a similar stability result already established for discrete-time quantum systems. This result implies the stability of such filtering process but does not necessarily ensure the asymptotic convergence of such quantum filters.

Bio: Nina H. Amini is a CNRS researcher at Laboratory L2S at CentraleSupelec since October 2014. She did her first postdoc from June 2012 for six months at ANU, College of Engineering and Computer Science and her second postdoc at Edward L. Ginzton Laboratory, Stanford University since December 2012. She received her Ph.D. in Mathematics and Control Engineering from Mines-ParisTech (Ecole des Mines de Paris), in September 2012. Prior to her Ph.D., she earned a Master in Financial Mathematics and Statistics at ENSAE and the Engineering Diploma of l’Ecole Polytechnique, in 2009. Her research interests include stochastic control, quantum control, (quantum) filtering theory, (quantum) probability, and (quantum) information theory.

S³: Modeling and mismodeling in radar applications: parameter estimation and bounds

Séminaire le 9 Juin 2015, 10h00 à CentraleSupelec (Gif-sur-Yvette) Salle des séminaires du L2S
Maria S. Greco, Department of Information Engineering, University of Pisa


The problem of estimating a deterministic parameter vector of acquired data is ubiquitous in signal processing applications. A fundamental assumption underlying most estimation problems is that the true data model and the model assumed to derive an estimation algorithm are the same, that is, the model is correctly specified.
This lecture will focus on the general case in which, for some non-perfect knowledge of the true data model or for operative constraints on the estimation algorithm there is a mismatch between assumed and true data model.
After a short first part dedicated to explain the radar framework of the estimation problem, the lecture will be dedicated to the evaluation of lower bounds on the Mean Square Error of the estimate of a deterministic parameter vector under misspecified model with particular attention to Mismatched Maximum Likelihood estimator and Huber bounds.

Bio: Maria S. Greco graduated in Electronic Engineering in 1993 and received the Ph.D. degree in Telecommunication Engineering in 1998, from University of Pisa, Italy. From December 1997 to May 1998 she joined the Georgia Tech Research Institute, Atlanta, USA as a visiting research scholar where she carried on research activity in the field of radar detection in non-Gaussian background.
    In 1993 she joined the Department of Information Engineering of the University of Pisa, where she is Associate Professor since December 2011. She’s IEEE fellow since January 2011 and she was co-recipient of the 2001 IEEE Aerospace and Electronic Systems Society’s Barry Carlton Award for Best Paper and recipient of the 2008 Fred Nathanson Young Engineer of the Year award for contributions to signal processing, estimation, and detection theory. She has been co-general-chair of the 2007 International Waveform Diversity and Design Conference (WDD07), Pisa, Italy, in the Technical Committee of the 2006 EURASIP Signal and Image Processing Conference (EUSIPCO), Florence, Italy, in the Technical Committee of the 2008 IEEE Radar Conference, Rome, Italy, in the Organizing Committee of CAMSAP09, Technical co-chair of CIP2010 (Elba Island, Italy), General co-Chair of CAMSAP2011 (San Juan, Puerto Rico), Publication Chair of ICASSP2014, Florence, Italy, Technical Co-Chair of the CoSeRa2015, Pisa, Italy and Special Session Chair of CAMSAP2015, Cancun, Mexico. She is lead guest editor of the special issue on "Advanced Signal Processing for Radar Applications" to appear on the IEEE Journal on Special Topics of Signal Processing, December 2015, she was guest co-editor of the special issue of the Journal of the IEEE Signal Processing Society on Special Topics in Signal Processing on "Adaptive Waveform Design for Agile Sensing and Communication," published in June 2007 and lead guest editor of the special issue of International Journal of Navigation and Observation on” Modelling and Processing of Radar Signals for Earth Observation published in August 2008. She’s Associate Editor of IET Proceedings – Sonar, Radar and Navigation, Associate Editor-in-Chief of the IEEE Aerospace and Electronic Systems Magazine, member of the Editorial Board of the Springer Journal of Advances in Signal Processing (JASP), Senior Editorial board member of IEEE Journal on Selected Topics of Signal Processing (J-STSP), member of the IEEE Signal Array Processing (SAM) Technical Committees. She's also member of the IEEE AES and IEEE SP Board of Governors and Chair of the IEEE AESS Radar Panel. She's as well SP Distinguished Lecturer for the years 2014-2015, AESS Distinguished Lecturer for the years 2015-2016 and member of the IEEE Fellow Committee.
     Maria is a coauthor of the tutorials entitled “Radar Clutter Modeling”, presented at the International Radar Conference (May 2005, Arlington, USA), “Sea and Ground Radar Clutter Modeling” presented at 2008 IEEE Radar Conference (May 2008, Rome, Italy) and at 2012 IEEE Radar Conference (May 2012, Atlanta, USA), coauthor of the tutorial "RF and digital components for highly-integrated low-power radar" presented at the same conference, of the tutorial "Recent Advances in Adaptive Radar Detection" presented at the 2014 International Radar Conference (October 2014, Lille, France) and co-author of the tutorial "High Resolution Sea and Land Clutter Modeling and analysis", presented at the 2015 IEEE International Radar Conference (May 2015, Washington DC, USA).
    Her general interests are in the areas of statistical signal processing, estimation and detection theory. In particular, her research interests include clutter models, spectral analysis, coherent and incoherent detection in non-Gaussian clutter, CFAR techniques, radar waveform diversity and bistatic/mustistatic active and passive radars. She co-authored many book chapters and more than 150 journal and conference papers.

Novel Microstereolithography (MSL) and Bulk Lithography (BL) technologies for polymer/ceramic 3D MEMS

Séminaire le 3 Juin 2015, 16h00 à CentraleSupelec (Gif-sur-Yvette) Salle des séminaires du L2S
Prof. Prasanna S. Gandhi


Polymers are increasingly being used for fabrication of MEMS for their advantages of low cost, easy disposability, high flexibility, and so on. With the area of printable organic electronics developing fast there are enormous possibilities with polymer MEMS, especially 3D. This talk will present two indigenously developed technologies for fabrication of polymer 3D MEMS.
The proposed MSL technology has demonstrated resolution of 6micron and a large overall size of fabricated component at the same time: a feature seldom found in other such systems in the literature. The core opto-mechanical scanner (patent pending) and mechatronic system built around it would be presented. This system is demonstrated to have positioning accuracy within 100 nm. Several cases of micro-component fabrication will be demonstrated. Main drawback of MSL is stair-stepping effects on slanted walls. To overcome this limitation, recently "Bulk Lithography" technology has been proposed by our group. The main principle used here is to impose spatial variation of laser energy dose while scanning. The method gives remarkable accuracy in getting free-form surface features desired for microlenses, tapered micro cantilevers, tapered diaphragm micromirrors and so on, which are otherwise not feasible to fabricate. Finally, ceramic microstereolithography and preliminary fabrication of ceramic microcomponents would be demonstrated. The proposed technologies hold potential for direct prototyping and also mass production of MEMS devices along with packaging.

Biography: P.S. Gandhi received the B.Eng. degree in from the University of Bombay, Mumbai in 1994 and the M.Tech degree from the Indian Institute of Technology, Bombay, Mumbai in 1996, both in mechanical engineering. He received the Ph.D. degree in mechanical engineering from the Rice University, Houston in 2001. Since 2001, he has been faculty member, currently Professor, in the Department of Mechanical Engineering at Indian Institute of Technology, Bombay, Mumbai. His research interests are in the areas of MEMS and Microsystems, Mechatronics, and Nonlinear Dynamical Systems and Control. He has been a recipient of 2006 BOYSCAST fellowship of Govt of India, 2007 Best faculty award (ME department) and Prof J.R.Issac fellowship. He has authored several patents and over 85 peer reviewed conference and journal papers. He has coordinated setup of a new laboratory Suman Mashruwala Microengineering Laboratory for research in Microdomain and has successfully developed technologies of Bulk Lithography and Microstereolithography for 3D MEMS fabrication in this laboratory. He has been a qualified teacher of stress relieving, life enhancing techniques of Art of Living foundation by Sri Sri Ravishankar

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