报告人: 卢琳璋教授(厦门大学数学科学学院二级教授)
报告标题: A structure-exploiting algorithm for solving a palindromic quadratic eigenvalue problem
时间: 2015-6-15(星期一)下午4:30
报告地点:数学系实验室
摘要:
In this talk, we discuss how to solve numerically the palindromic quadratic eigenvalue problem (PQEP) (λ2 AT+ λ Q + A)z=0 arising from the vibration analysis of high speed trains, where A, Q m-by-m are matrices with special structures: both Q and A are m-by-m block matrices with each block being q-by-q, and moreover they are complex symmetric, block tridiagonal, and block Toeplitz. Recently, Guo and Lin (SIAM J. Matrix Anal. Appl., 31 (2010), 2784--2801) proposed an efficient solvent approach to solve this PQEP by computing the so-called stabilizing solution to the n-by-n matrix equation X+ATX-1A=Q via the doubling algorithm. It is shown here that the stabilizing solution X differs from Q only in its (m,m)th block position, and thus it suffices to only compute that block. The latter is shown to satisfy another matrix equation having the same form as X+ATX-1A=Q but of q-by-q. We then apply the doubling algorithm to the q-by-q matrix equation to the block and the whole stabilizing solution.
Numerical examples are presented to show the effectiveness of the new method.
汕头大学理学院
2015年6月12日