IEEE GRSS Shanghai Chapter 复旦大学电磁波信息科学教育部重点实验室 学术报告 Physics-Inspired Convolutional Neural Network for Solving Full-Wave Inverse Scattering Problems Prof. Xudong Chen National University of Singpore 复旦大学光华楼东主楼1101, 2018年7月2日, 上午9:00-10:15 Abstract: The talk aims to solve a full-wave inverse scattering problem (ISP), which is a quantitative imaging problem, i.e., to reconstruct the permittivities of dielectric scatterers from the knowledge of measured scattering data. This talk proposes the convolution neural network (CNN) technique to solve full-wave ISPs. In order to make machine learning more powerful, a deep understanding of the corresponding forward problem is desirable. In solving ISP, the concept of induced current plays an essential role in the proposed CNN technique, which enables us to design the architecture of learning machine such that unnecessary computational effort spent in learning wave physics is minimized or avoided. Numerical simulations demonstrated that the proposed CNN scheme outperforms a brute-force application of CNN. The proposed deep learning inversion scheme is promising in providing quantitative images in real time . Bio: Xudong Chen received the B.S. and M.S. degrees in electrical engineering from Zhejiang University, China, in 1999 and 2001, respectively, and the Ph.D. degree from the Massachusetts Institute of Technology, Cambridge, MA, USA, in 2005. Since 2005, he has been with the National University of Singapore. He has published 150 journal papers, with total citation 4,700+ according to ISI Web of Science (SCI). He has authored the book Computational Methods for Electromagnetic Inverse Scattering (Wiley-IEEE, 2018). His research interests mainly include electromagnetic inverse scattering, sensing and data fusion, optical/infrared/microwave scanning microscopy, optical encryption, and metamaterials. He has organized 20+ sessions on the topic of inverse scattering and imaging in various conferences. He has been members of organizing committees of 10+ conferences, serving as General Chair, TPC Chair, Award Committee Chair, etc. He has been an Associate Editor of the IEEE Transactions on Microwave Theory and Techniques since 2015. Dr. Chen was a recipient of the Young Scientist Award by the Union Radio Scientifique Internationale in 2010 and of the Best Paper Award in IEEE ICCEM conference. He is a Fellow of The Electromagnetics Academy.

IEEE GRSS Shanghai Chapter 复旦大学电磁波信息科学教育部重点实验室 学术报告 Significance of Meso-scale Structures to the Ionosphere/Thermosphere Prof. Yue Deng University of Texas Arlington, TX USA 复旦大学光华楼东主楼1101, 2018年7月2日, 上午10:15-12:00 Abstract: A recent significant change in our understanding of the ionosphere-thermosphere system is the frequent driving by dynamic meso-scale structures (50 km - 500 km) that couple to the magnetosphere in the polar cap region, the dayside cusp and along auroral oval and sub-auroral magnetic field lines. These structures play a critical role in Space Weather dynamics, interacting with the more slowly changing, large-scale structure that is more directly driven by interaction with the solar wind. The Global Ionosphere Thermosphere Model (GITM), a self-consistent non-hydrostatic model in the upper atmosphere with a flexible resolution, is suitable for studying transient meso-scale phenomena. To improve the description of meso-scale structures in geomagnetic forcing and to evaluate the influence of such structures on the global dynamics of the upper atmosphere, various data and models are utilized to investigate the variations of energy inputs in the cusp, sub-auroral regions and within flow bursts, and their influences on the coupled thermosphere-ionosphere system. Bio: Yue Deng is a Professor in the Department of Physics at the University of Texas at Arlington, Texas USA. She received her BS and MS degrees at the Peking University in 1997 and 2001, and her PhD degree at the University of Michigan at Ann Arbor in 2006. She is the co-developer of the first global non-hydrostatic model in the upper atmosphere, Global Ionosphere Thermosphere Model (GITM). Her main research interest is the coupling between ionosphere and thermosphere under different geospace conditions. Dr. Deng was awarded the National Science Foundation (NSF) CAREER award and is the Principal Investigator of the Multidisciplinary University Research Initiative (MURI) project. Her research is supported by NSF, NASA and Air Force Office for Scientific Research (AFOSR). She is serving on the National Academy of Sciences (NAS) Committee on Solar and Space Physics (CSSP) and CEDAR Science Steering Committee (CSSC).