1. School of Management Engineering, Qingdao University of Technology, Qingdao 266520, China
2. PetroChina Huabei Oilfield Company, Cangzhou 062552, China
3. Faculty of Society and Design, Bond University, Robina, QLD 4226, Australia
4. Department of Civil Engineering, University of Utah, Salt Lake City, UT 84112, USA