发布时间:2020-10-20
报告人 :张继伟 武汉大学 教授
报告人简介 :
武汉大学37000cm威尼斯教授,博士生导师。 2003和2006年在郑州大学获得学士和硕士学位,2009年在香港浸会大学获得博士学位。随后在南洋理工大学和纽约大学克朗所从事博士后研究,2014年5月在北京计算科学研究中心工作,2018年11月到武汉大学工作。现主持一项国家自然科学基金面上项目,并参与一项重点项目。主要研究领域包括偏微分方程和非局部模型的数值解法,以及神经科学的建模与计算。主要成果发表在SIAM Journal on Scientific Computing, SIAM Journal on Numerical Analysis, Mathematics of Computation, Journal of Computational Neuroscience等国际知名期刊上。
报告题目:非局部到局部模型关于非局部效应参数的一致二阶逼近
报告摘要:In this talk we focus on the uniform convergence rates from nonlocal models to the corresponding local models, and presents a necessary condition to guarantee the first-order and second-order convergence rate with respect to a nonlocal horizon parameter $\delta$ without extra assumptions on the regularity of nonlocal solutions. To do so, we first revisit the maximum principle for nonlocal models, and present the uniqueness of the nonlocal solutions. After that, we give the methodology to address the truncated errors on the volume constrains or Neumann BCs, and then combine the resulting errors from boundary layers with the maximum principle to obtain the uniform convergence order. Our analysis shows that the constant value continuation of the boundary conditions of local problems only leads to first-order convergence rate. And if we expect to have second-order convergence rate, the information of first-order derivatives for local problems on the boundaries is required. One and two dimensional numerical examples are given to verify the effectiveness of our theoretical analysis.
报告时间 :2020年10月27日上午8:00-10:00
报告地点 :腾讯会议室:130644002