1. Professor, Dept. of Civil and Environmental Engineering, California Polytechnic State Univ., San Luis Obispo, CA.
2. Research Fellow, Dept. of Civil and Environmental Engineering, California Polytechnic State Univ., San Luis Obispo, CA.
3. Engineer, Pells Sullivan Meynink Engineering Consultants, North Ryde, NSW, Australia.
4. Director, Global Waste Research Institute, California Polytechnic State Univ., San Luis Obispo, CA.