Title: Domain Decomposition Methods for Solving The Helmholtz Problem
       by High-Order Finite Element Methods

Authors: Youngjoon Cha and Seongjai Kim

Abstract:
An iterative domain decomposition method is considered for solving
the Helmholtz wave equation by high-order quadrilateral finite element
methods.  The iteration is performed in a block Jacobi manner with a
minimum overlap.  For the interface operator, a Robin boundary condition
is employed in a modified form which fits possible discontinuities of
the normal components of the discrete flux on the subdomain interfaces.
The algorithm is analyzed using energy estimates.  Numerical results are
given to show the effectiveness of the algorithm for the simulation of
high-frequency waves in heterogeneous media in the two-dimensional space.