1. Eulerian Applications Group, Los Alamos National Laboratory, Los Alamos, NM 87544;
2. Department of Computer Science, Texas Tech University, Lubbock, TX 79409
3. Eulerian Applications Group, Los Alamos National Laboratory, Los Alamos, NM 87544
4. High Performance Computing Division, Los Alamos National Laboratory, Los Alamos, NM 87544
5. Computer Science Research Institute, Sandia National Laboratories, Albuquerque, NM 87123