[1] Hebei Univ Technol, Sch Econ & Management, Tianjin 300401, Peoples R China
[2] Lawrence Berkeley Natl Lab, China Energy Grp, 1 Cyclotron Rd, Berkeley, CA 94720 USA
[3] Chongqing Univ, Sch Management Sci & Real Estate, Chongqing 400044, Peoples R China
[4] Chongqing Univ, Sch Publ Affairs, Chongqing 400044, Peoples R China