1. Department of Electrical and Electronic Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong
2. Department of Electrical and Computer Engineering, National University of Singapore, Singapore
3. Solar Energy Research Institute of Singapore, National University of Singapore, Singapore
4. Department of Electrical Engineering, School of Automation, Nanjing University of Science and Technology, Nanjing, China
5. School of Electrical Engineering and Automation, Harbin Institute of Technology, Harbin, China
6. Department of Electrical Engineering, Stanford University, Stanford, CA, USA