1. Department of Mechanics, Tianjin University, Tianjin 300072, China e-mail:
2. Science and Technology on Reactor System Design Technology Laboratory, Nuclear Power Institute of China, Chengdu 610041, China e-mail:
3. Fellow ASME School of Engineering, University of California, Merced, CA 95343;
4. Honorary Professor Department of Mechanics, Tianjin University, Tianjin 300072, China e-mail: