[1] Henan Univ Technol, Coll Elect Engn, Zhengzhou 450052, Peoples R China
[2] Beijing Inst Technol, Sch Automat, Beijing 100081, Peoples R China
[3] North China Univ Water Resource & Elect Power, Coll Surveying & Geoinformat, Zhengzhou 450045, Henan, Peoples R China
[4] Yanshan Univ, Sch Elect Engn, Qinhuangdao 066004, Hebei, Peoples R China