Towards Robust Two-Level Methods For Indefinite Systems
نویسنده
چکیده
Despite the fact that iterative solution techniques are recently gaining recognition among practitioners and finding their way into commercial software arena, the current state of the art in iterative methods remains unsatisfactory in many respects. Users of large production codes such as ANSYS, NASTRAN, ALGOR, SDRC, EMRC and ANSYS often observe many “bad” cases resulting from poorly conditioned or indefinite systems for which their iterative solvers converge prohibitively slow or systematically break. Consequently and perhaps rightfully so, a number of commercial software houses, including ABAQUS, refrain from utilizing iterative solver technology primarily because of its lack of robustness.
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