1. Assistant Professor, Univ. of Texas at El Paso, 500 W. University Ave., Engineering Building, El Paso, TX 79968 (corresponding author).
2. Principal Engineer, Applied Research Associates, Inc., 104 Research Rd., Building 9738, Tyndall AFB, FL 32403.
3. Research Engineer, Air Force Research Laboratory, 104 Research Rd., Building 9738, Tyndall AFB, FL 32403.