**Title: Solving ill-posed problems by dynamical system method**

**Keynote Speaker: Liu Jijun **

**Abstract: **

The ill-posed problems are quite popular arising from many engineering areas such as contamination control, geophysics, remote sensing and image process. The main difficulty for solving these problems is the instability, namely, the small perturbations in input data can lead large errors in the solutions. Consequently, many regularizing schemes such as Tikhonov regularizations, iterative regularizations are proposed to solve these problems efficiently, in the sense of recovering the stability by solving an approximate well-posed problem. In this talk, we will introduce the essence of the ill-posed problems and the corresponding solution schemes called dynamical system method, which construct the regularizing schemes by a ODE system.

**Introduction to the Speaker: **

Liu Jijun, Ph.D., second-grade professor and doctoral supervisor of Southeast University, is an expert enjoying the special government allowance of the State Council. He is currently the Executive Deputy Director of Nanjing Center for Applied Mathematics (NCAM), Standing Director of China Society for Industrial and Applied Mathematics, member of the Organizing Committee of Contemporary Undergraduate Mathematical Contest in Modeling (CUMCM), member of the Professional Committee of Mathematical Contest in Modeling of China Society for Industrial and Applied Mathematics and Vice President of Jiangsu Society for Computational Mathematics. Besides, he is also the host of national top-quality course *Mathematical Modeling and Mathematical Experiment*. And he is the Standing Director of the 8^{th} and 9^{th} Council of China Society for Computational Mathematics, and Chairman of the 5^{th} and 6^{th} Council of Jiangsu Society for Industrial and Applied Mathematics (JSIAM). He has studied inverse problems of mathematical physics as well as mathematical theory and method of scientific computing on large scales and medium imaging for a long run, and presided over multiple projects of National Natural Science Foundation of China and Natural Science Foundation of Jiangsu Province. He has published over 100 academic papers in SIAM Journal on Applied Mathematics (SIAP), SIAM Journal on Scientific Computing (SISC), Inverse Problems and Inverse Problems and Imaging, and 2 academic monographs in Science Press. He once served as the editorial board member of Inverse Problems in Sciences and Engineering, and is now the editorial board member of Journal of Inverse and Ill-Posed Problems. He was selected as the young backbone teacher and the young and middle-aged academic leader of the "Qing Lan Project" of Jiangsu Province, as well as the third-level training candidate of the "333 Talent Training Program" of Jiangsu Province. He once won the First Prize of National Outstanding Teacher of Baosteel Education Foundation, and the First Prize of Teaching Achievement of Jiangsu Province, the Third Prize of Natural Science of Jiangsu Province and the Second Prize of Natural Science of Ministry of Education as a host.

**Inviter: **

Rui Hongxing, Professor of School of Mathematics

**Time: **

15:00 on September 18 (Friday)

**Location: **

Lecture Hall 1032, Block B, Zhixin Building, Central Campus

**Sponsored by: School of Mathematics, Shandong University **