1. Performance Analysis Center of Production and Operations Systems (PacPos), Northwestern Polytechnical University, Xi'an, Shaanxi, People's Republic of China
2. Department of Industrial Engineering, School of Mechanical Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi, People's Republic of China
3. Department of Management Studies, College of Business, University of Michigan-Dearborn, Dearborn, MI, USA