1. Assistant Professor, Construction Engineering and Management, National Institute of Transportation, National Univ. of Sciences and Technology, Risalpur Campus, Risalpur Cantonment 24080, Pakistan; formerly, Ph.D. Candidate, Tsinghua-Gammon Construction Safety Research Center, School of Civil Engineering, Tsinghua Univ., Beijing 100084, China.
2. Professor, Director, Tsinghua-Gammon Construction Safety Research Center, School of Civil Engineering, Tsinghua Univ., Beijing 100084, China.
3. Associate Professor and Graduate Program Director of Construction Management, Florida International Univ., Miami, FL 33174.