应数学系应用数学研究所陈勇副教授邀请，美国密歇根科技大学的孙继广副教授将于近日来我系交流访问，并作学术报告。报告题目、时间、地点及摘要如下，欢迎感兴趣的师生参加！

题目: The reconstruction of obstacles in a waveguide using finite elements

时间：2015年8月3日15:30-17:00

地点：格物楼503室

报告摘要: We consider the reconstruction of penetrable obstacles embedded in a waveguide from near-field data due to point sources. The inverse problem is formulated as an optimization problem with a regularization term. The linear sampling method is used to obtain an initial guess of the obstacle. We develop a quasi-Newton method using a carefully designed finite element method. The stiffness matrix, mass matrix and right hand side are assembled only once. At each iteration, only minor changes are made to the mass matrix and right hand side. The effectiveness of the proposed method is demonstrated by numerical examples.

报告人简介：孙继广副教授，本科毕业于清华大学，2005年在University of Delaware获得博士学位，主要从事偏微分方程数值方法、逆散射问题、科学计算及地球物理中的电磁方法等方面的研究工作，发表论文40余篇，其中在国际顶级杂志《Inverse Problems》、《SIAM J. Numer. Anal.》等发表论文十余篇.

详情请参见个人主页:http://www.math.mtu.edu/~jiguangs/Homepage_of_Jiguang_Sun/Welcome.html