1. Graduate Research Assistant, Dept. of Civil and Environmental Engineering, Villanova Univ.
2. Associate Professor, Dept. of Civil and Environmental Engineering, Villanova Univ..
3. Director, Global Waste Research Institute, California Polytechnic State Univ., San Luis Obispo, CA.
4. Professor, Dept. of Civil and Environmental Engineering, California Polytechnic State Univ., San Luis Obispo, CA.