1. Northwest Institute of Historical Environment, Socio-Economic Development, Shaanxi Normal University, No. 620, West Chang’an Avenue, Xi’an 710119, China
2. Shaanxi Mineral Resources and Geological Survey, No. 243, West Youyi Road, Xi’an 710068, China
3. College of Economics and Management, Xi’an University Posts & Telecommunications, No. 618, West Chang’an Avenue, Xi’an 710121, China