应影像实验室邀请，5月6日（周四 ）晚上20:00-21:30，法国国家科学院院长 Patrick Flandrin 教授给我院师生做学术报告，具体情况如下：
Estimating Covid-19 reproduction number: A spatio-temporal regularized approach
参会链接：zoom会议ID：941 9817 4855，密码：114243https://univ-rennes1-fr.zoom.us/j/94198174855
Among the different indicators that quantify the spread of an epidemic—such as the on-going Covid-19—stands first the reproduction number which measures how many people can be contaminated by an infected person. In order to permit the monitoring of the evolution of this number, a new estimation procedure has been proposed, assuming a well-accepted model for current incidence data, based on past observations. The originality of the proposed approach is twofold: 1) the estimation of the reproduction number is achieved by convex optimization within a proximal-based inverse problem formulation, with constraints aimed at promoting piecewise linearity; 2) the approach is developed in a multivariate setting, allowing for the simultaneous handling of multiple time series attached to different geographical regions, together with a spatial (graph-based) regularization of their evolutions in time. The justification of the proposed methodology will be outlined and examples of its real application to Covid-19 will be discussed, both for metropolitan France and for the world.
Patrick Flandrin received the engineer degree from ICPI Lyon, France, in 1978, and the Doct.-Ing. and Docteur d’État degrees from INP Grenoble, France, in 1982 and 1987, respectively. He joined CNRS in 1982, where he is currently Research Director. Since 1991, he has been with the Signals, Systems and Physics Group, within the Physics Department at ENS de Lyon, France. He has been President of GRETSI, the French Association for Signal and Image Processing, from 2009 to 2019. His research interests include mainly nonstationary signal processing (with emphasis on time-frequency and time-scale methods), scaling stochastic processes and complex systems. He authored two monographs in those areas, the most recent one being Explorations in Time-Frequency Analysis (Cambridge University Press, 2018). Dr. Flandrin was awarded the Philip Morris Scientific Prize in Mathematics (1991), the SPIE Wavelet Pioneer Award (2001), the Prix Michel Monpetit from the French Academy of Sciences (2001), the Silver Medal from CNRS (2010), and the Technical Achievement Award from the IEEE Signal Processing Society (2017). Past Distinguished Lecturer of the IEEE Signal Processing Society (2010-2011), he is a Fellow of the IEEE (2002) and of EURASIP (2009). Elected member of the French Academy of Sciences in 2010, he is currently its President for the period 2021-2022.