Si informano tutti gli interessati che, nell'ambito del programma Visiting Professor 2016/2017 finanziato dalla Regione Autonoma della Sardegna, giovedì 4 maggio 2017 alle ore 18:00 il Dott. Paolo Frasca terrà in Aula Mocci, Dipartimento di Ingegneria Elettrica ed Elettronica, Pad. A, Facoltà di Ingegneria ed Architettura, Via Marengo 2,  il seguente seminario:


Speaker: Dr. Paolo Frasca (Research scientist at CNRS, Grenoble, France)

Title: The Observability Radius of Network Systems

Abstract: 

In this talk, we introduce the observability radius of network systems, which measures the robustness of a network to perturbations of the edges. We consider linear networks, where the dynamics are described by a weighted adjacency matrix, and dedicated sensors are positioned at a subset of nodes. We allow for perturbations of certain edge weights, with the objective of preventing observability of some modes of the network dynamics. Our work considers perturbations with a desired sparsity structure, thus extending the classical literature on the controllability and observability radius of linear systems. We propose an optimization framework to determine a perturbation with smallest Frobenius norm that renders a desired mode unobservable from the existing sensor nodes. Additionally, we study the expected observability radius of random networks with given structure. In this context, we provide fundamental robustness bounds dependent on the connectivity properties of the network and we analytically characterize optimal perturbations of line and star networks, showing that line networks are inherently more robust than star networks. To conclude (if time permits), we illustrate the use of our results to study a novel class of topology attacks against power networks. 

Short biography:

Paolo Frasca received the Ph.D. degree in Mathematics for Engineering Sciences from Politecnico di Torino, Italy, in 2009. Between 2008 and 2013, he has held research and visiting positions at the University of California, Santa Barbara (USA), at the IAC-CNR (Rome, Italy), at the University of Salerno (Italy), and at the Politecnico di Torino. From 2013 to 2016, he has been an Assistant Professor at the University of Twente, the Netherlands. In 2016, he has been a visiting professor at the LAAS, Toulouse, France. Since October 2016, he is a CNRS researcher at GIPSA-lab, Grenoble, France.
His research interests are in the theory of network systems and cyber-physical systems, with applications to robotic, sensor, infrastructural, and social networks. On these topics, Dr. Frasca has (co)authored more than fifty journal and conference papers and has given invited talks at several international institutions and events, including the 2015 SICE International Symposium on Control Systems in Tokyo. He is a recipient of the 2013 SIAG/CST Best SICON Paper Prize.
Dr. Frasca has served in the Editorial Boards of several conferences (IEEE CDC, ACC, ECC, MTNS, IFAC NecSys) and is currently serving on the Editorial Boards of the International Journal of Robust and Nonlinear Control, the Asian Journal of Control, and the IEEE Control Systems Letters.