1. Research Associate, Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong Univ., Chengdu, China; Postdoc Researcher, Dept. of Civil and Environmental Engineering, Univ. of Wisconsin-Madison, Madison, WI.
2. Research Scientist, Recycled Materials Resource Center-3rd Generation (RMRC-3G), Univ. of Wisconsin-Madison, WI.
3. Graduate Research Assistant, Dept. of Environmental Science and Engineering, Southwest Jiaotong Univ., Chengdu, China.
4. Professor Emeritus, Dept. of Civil and Environmental Engineering, Univ. of Wisconsin-Madison, Madison, WI.
5. Associate Professor, Dept. of Civil and Environmental Engineering, Jackson State Univ., Jackson, MS.