1. Department of Mathematical Sciences; Kent State University; Kent OH 44242 U.S.A.
2. Department of Aeronautics and Astronautics; Stanford University; Stanford CA 94305 U.S.A.
3. Department of Mechanical Engineering; Stanford University; Stanford CA 94305 U.S.A.
4. Institute for Computational & Mathematical Engineering; Stanford University; Stanford CA 94305 U.S.A.