SHENGPENG FU1,2, JIBIN ZHAO1, RENBO XIA1 AND WEIJUN LIU1
1Shenyang Institute of Automation
Chinese Academy of Sciences
Shenyang, 110016 P.R. China
2University of Chinese Academy of Sciences
Beijing, 100049 P.R. China
E-mail: {fushengpeng; jbzhao; xiarb; wjliu}@sia.cn