1. Professor and Director, Western Illinois Univ., 1 Univ. Cir., Macomb, IL 61455 (corresponding author). E-mail: rc-viadero@wiu.edu
2. Research Professor, West Virginia Univ., P.O. Box 6103, Morgantown, WV 26506. E-mail: RHFortney@mail.wvu.edu
3. Engineering Scientist, West Virginia Univ., P.O. Box 6103, Morgantown, WV 26506. E-mail: AETierney@mail.wvu.edu