报告题目 (Title)：A Parallel-in-Time Algorithm for High-Order BDF Discretization for Diffusion and Subdiffusion Equations (扩散与亚扩散方程高阶向后差分格式的时间并行算法)
报告人 (Speaker)：周知 助理教授（香港理工大学）
报告时间 (Time)：2022年9月7日(周三) 15:00-17:00
报告地点 (Place)：线上腾讯会议 会议 ID：420 828 754
邀请人(Inviter)：李常品、蔡敏
报告摘要：In this talk, I will present a parallel-in-time algorithm for approximately solving parabolic equations. We apply the k-step backward differentiation formula, and then develop an iterative solver by using the waveform relaxation technique. Each resulting iterate represents a periodic-like system, which could be further solved in parallel by using the diagonalization technique. The convergence of the waveform relaxation iteration is theoretically examined by using the generating function method. The argument could be further applied to the time-fractional subdiffusion equation, whose discretization shares common properties of the standard BDF methods, because of the nonlocality of the fractional differential operator. Some illustrative numerical results will be presented to complement the theoretical analysis.