[Wang, Gai-Ge] Ocean Univ China, Dept Comp, Qingdao, Peoples R China.^[Bai, Danyu] Nanjing Forestry Univ, Coll Econ & Management, Nanjing, Jiangsu, Peoples R China.^[Gong, Wenyin;Yan, Xuesong] China Univ Geosci, Sch Comp Sci, Wuhan, Hubei, Peoples R China.^[Ren, Teng] Cent South Univ Forestry & Technol, Sch Transportat & Logist, Changsha, Hunan, Peoples R China.^[Liu, Xiaobo] China Univ Geosci, Sch Automat, Wuhan, Hubei, Peoples R China.