Xref: utzoo ont.events:1288 uw.cs.grad:18 uw.talks:14 Path: utzoo!attcan!utgpu!watmath!thunder!water!wlrush From: wlrush@water.waterloo.edu (Wenchantress Wench Wendall) Newsgroups: ont.events,uw.cs.grad,uw.talks Subject: SCIENTIFIC COMPUTATION SEMINAR Keywords: Dimpy Pathria, graduate student, Dept. of Computer Science, Message-ID: <2629@water.waterloo.edu> Date: 1 Sep 89 17:17:55 GMT Distribution: ont Organization: U of Waterloo, Ontario Lines: 44 will speak on ``Adaptive Mesh Methods for the Fourier Solution of Certain Wave Problems.'' DEPARTMENT OF COMPUTER SCIENCE UNIVERSITY OF WATERLOO SEMINAR ACTIVITIES SCIENTIFIC COMPUTATION SEMINAR -Friday, September 8, 1989 Dimpy Pathria, graduate student, Dept. of Computer Science will speak on ``Adaptive Mesh Methods For The Fourier Solution of Certain Wave Problems.'' TIME: 10:30 a.m. ROOM: DC 3540 ABSTRACT In a previous talk we described the pseudospectral split-step method for solving certain nonlinear Schrodinger equations. Pseudospectral approximations are often used for discretizing the spatial component of evolutionary problems. In this talk we consider enhancing the performance of such methods by two adaptive grid generation schemes. The first scheme addresses the temporal nonuniformity commonly exhibited by solutions of nonlinear evolutionary equations. By integrating the problem independently on interleaved grids and comparing the Fourier coefficients as calculated on each, it provides a mechanism for automatically varying the degree of the interpolating trigonometric polynomial. The second scheme addresses the spatial nonuniformity of the solutions, in which the resolution requirements vary over the domain. It is an adaptive meshing algorithm for Fourier interpolation, where the collocation nodes are dynamically located in accordance with the needs of the problem. Numerical experiments demonstrate the advantages of the adaptive discretization schemes.