SEMINARS & COLLOQUIA
WEEK OF: Aug. 20
4:00 pm Ellis B. Stouffer Colloquium, 306 Snow
***Refreshments will be served in 406 Snow at 3:30 pm***
Prof. Volker Mehrmann
Inst. f. Mathematik, TU Berlin, Germany
In this paper we study large scale quadratic eigenvalue problems
arising in the numerical simulation (via finite element methods) of
the elastic deformation of anisotropic materials.
We discuss the computation of the eigenvalues and eigenvectors
closest to the imaginary axis which is the interior of the spectrum.
The numerical methods is constructed to reflect as much as possible
the structure (here an eigenvalue symmetry) of the physical problem.
To do this we use an implicitely restarted
shift-and-invert Arnoldi approach with a rational function
that inherits the structure of the problem.
We present some numerical examples that prove the superiority
of the new structured approach over classical unstructured
methods and we show how the same procedure can be used
in the context of slightly damped gyroscopic systems.