1. Key Laboratory of Contemporary Design and Integrated Manufacturing Technology, Ministry of Education, Northwestern Polytechnical University, Xi’an, P. R. China
2. Research & Development Institute in Shenzhen, Northwestern Polytechnical University, Guangdong, P. R. China
3. School of Business, Macau University of Science and Technology, Macao, P. R. China
4. Key Laboratory of Road Construction Technology and Equipment of MOE, Chang’an University P. R. China
5. Economics and Management School, Wuhan University, Wuhan, P. R. China