1. School of Automation Science and Electrical Engineering, Beihang University, Beijing, People's Republic of China
2. Beijing Advanced Innovation Center for Big Data and Brain Computing, Beihang University, Beijing, People's Republic of China
3. School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, Singapore
4. School of Automation, Chongqing University, Chongqing, People's Republic of China