1. School of Automation, China University of Geosciences, Wuhan 430074, China, also with the Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems, Wuhan 430074, China, and also with the Engineering Research Center of Intelligent Technology for Geo-Exploration, Ministry of Education, Wuhan 430074, China.
2. School of Automation, China University of Geosciences, Wuhan 430074, China, also with the Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems, Wuhan 430074, China, and also with the Engineering Research Center of Intelligent Technology for Geo-Exploration, Ministry of Education, Wuhan 430074, China (e-mail: ckzhang@cug.edu.cn)
3. State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074, China.
4. Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ, U.K..