1. Brown University, Providence, RI 02912 USA.
2. Center for Applied Mathematics, Cornell University, Ithaca, NY 14850 USA.
3. University of Michigan, Ann Arbor, MI 48109 USA.
4. Rensselaer Polytechnic Institute, Troy, NY 12180 USA.
5. University of California, Los Angeles, CA 90095 USA.
6. DEVCOM Army Research Laboratory, Research Triangle Park, NC 27709 USA.
7. Jacobs Technology Inc., Air Force Research Laboratory, Edwards Air Force Base, CA 93524 USA.
8. In-Space Propulsion Branch, Air Force Research Laboratory, Edwards Air Force Base, CA 93524 USA.