HONG-CHAO ZHANG, PhD, is Associate Professor of Industrial Engineering at Texas Tech University, Texas, USA. He received his PhD in manufacturing engineering from the Technical University of Denmark, Lyngby, Denmark, and his MS in mechanical engineering from the University of Aalborg, Aalborg, Denmark. Dr. Zhang has supervised many research projects, including projects funded by the National Science Foundation. He has published one previous book, six book chapters, and more than 70 refereed articles in a variety of international journals and other open literature.