1. a Department of Industrial and Manufacturing Systems Engineering , Louisiana State University , Baton Rouge, LA, 70803-6409, USA
2. b ABB Engineering Automation (ASEA Brown Boveri) , San Jose, California, USA.
3. c Department of Industrial Engineering , Texas A&M University , College Station, TX, 77843-3131, USA.
4. d Pohang Institute of Technology , Pohang, South Korea