1. Graduate Student, Univ. of California San Diego & San Diego State Univ., 9500 Gilman Dr., La Jolla, CA 92093 (corresponding author).
2. Professor, Univ. of California San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0411.
3. Associate Professor, San Diego State Univ., 5500 Campanille Dr., San Diego, CA 92182-1308.
4. Principal Engineer Scientist, The Boeing Company, P.O. Box 3707, MC 67-MH, Seattle, WA 98124-2207.