[Li, Junyi; Yang, Xiping] Shaanxi Normal Univ, Sch Geog & Tourism, Xian 710119, Shaanxi, Peoples R China.
[Li, Junyi; Yang, Xiping] Shaanxi Key Lab Tourism Informat, Xian 710119, Shaanxi, Peoples R China.
[Fang, Zhixiang] Wuhan Univ, State Key Lab Informat Engn Surveying Mapping & R, Wuhan 430079, Hubei, Peoples R China.
[Yin, Ling] Chinese Acad Sci, Shenzhen Inst Adv Technol, 1068 Xueyuan Rd, Shenzhen 518005, Peoples R China.
[Zhou, Yang] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Hubei, Peoples R China.