数学与系统科学研究院

计算数学所学术报告

报告人：        Hailiang Liu

Iowa State University, USA

报告题目 Computing High-Frequency Waves By the Level Set Method

Abstract: We introduce a new level set method for computational high frequency wave propagation in dispersive media, with an application to linear Schrodinger equations with efficiently highly oscillating initial data. The high-frequency asymptotics of dispersive equations often lead to the well known WKB system, where the phase evolves according to a nonlinear Hamilton-Jacobi equation and the intensity of the plane wave is governed by a linear conservation law. Based on the Hamilton-Jacobi equation wave fronts with multi-phases are constructed and captured by solving a linear Liouville equation in the phase space, and the multi-valued phase is resolved via the intersection of several zero level sets in an augmented phase space. In this context we also discuss the new development on computing multi-valued energy density and other physical observables.

报告时间：2004年7月13日  下午3：00

报告地点：科技综合楼三层报告厅