1. Postdoctoral Research Associate, Dept. of Biological Systems Engineering, Virginia Polytechnic Institute and State Univ. (Virginia Tech), Blacksburg, VA 24061 (corresponding author).
2. Associate Professor, Dept. of Civil and Environmental Engineering, Univ. of Tennessee, Knoxville, TN 37996.
3. Professor, Dept. of Biosystems Engineering and Soil Science, Univ. of Tennessee, Knoxville, TN 37996.
4. Research Associate II, Dept. of Biosystems Engineering and Soil Science, Univ. of Tennessee, Knoxville, TN 37996.