一、题目

Relative expander graphs and the coarse Baum-Connes conjecture

二、主讲人

梁栋

三、摘要

Efficient numerical computations of Maxwell’s equations are extremely crucial in electromagnetics and applications. When the domains of interest contain local solution behavior and geometrical feature or only occupy small parts of computational domains in practical problems, the computation of Maxwell’s equations is required to improve the resolution capacity and efficiency of solution, and thus it is interesting to utilize local mesh refinements over grids. However, in the presence of local mesh refinements, the sudden change of the mesh sizes inevitably produces spurious reflections in the electromagnetic waves, where the difficult task is to provide the required and suitable interface schemes/conditions to the local refinements of FDTD methods near the interfaces. In this talk, I will present our recent developments of energy-preserving S-FDTD schemes for metamaterial electromagnetics with Lorentz model and local mesh-refined FDTD schemes for Maxwell’s equations. Theoretical analysis, fast implementation and numerical experiments will be reported.

四、主讲人介绍

梁栋教授，加拿大约克大学(York Univ)终身正教授。长期从事偏微分方程数值解、环境和能源数值模拟、多孔介质渗流力学计算方法、计算电磁学等方面的研究工作。在大气环境气溶胶预测、油藏数值模拟、地下水环境计算、Maxwell方程计算、超材料电磁计算研究中取得重要成果。在包括国际权威期刊J. Comput. Phys.; SIAM J. Numer. Anal.; SIAM J. Sci. Comput.; Numer. Math.; IMA J. Appl. Math.; IMA J. Numer. Anal.; Atmos. Environ.; J. Aerosol Sci.; J. Sci. Comput.; J. Nonlinear Sci.; IEEE Trans. Antennas Propagat.等发表论文120余篇。2012年获得加拿大国家自然科学基金(NSERC)的DAS奖励。近年来，承担加拿大国家自然科学基金(NSERC)项目多项，并承担加拿大 MITACS 项目。

五、邀请人

芮洪兴 数学学院教授

六、时间

12月6日（周一）10:00

七、地点

腾讯会议：484 255 884 会议密码：211206

八、主办方

山东大学数学学院