[Wu, C. B.; Lv, J.] Shandong Univ Sci & Technol, Coll Econ & Management, Qingdao 266590, Peoples R China.
[Guan, P. B.] Beijing Univ Technol, Coll Environm & Energy Engn, Beijing 100124, Peoples R China.
[Zhong, L. N.] Cent China Normal Univ, Sch Polit & Int Studies, Wuhan 430079, Peoples R China.
[Hu, X. F.] Shandong Univ Sci & Technol, Coll Humanity & Law, Qingdao 266590, Peoples R China.
[Huang, G. H.] Univ Regina, Fac Engn, Environm Syst Engn Program, Regina, SK S4S 0A2, Canada.