1. Assistant Professor, Dept. of Civil and Architectural Engineering, Univ. of Wyoming, Laramie, WY 82071 (corresponding author).
2. Associate Research Fellow, Construction and Economy Research Institute of Korea, Construction Bldg., 711, Eonju-ro, Seoul 153-701, Korea.
3. Professor, Dept. of Construction Science, Texas A&M Univ., College Station, TX 77843.
4. President, Gransberg & Associates, Inc., P.O. Box 2395, Norman, OK 73026.