1. School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China
2. State Key laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an 710049, China
3. Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08540, USA
4. Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California 92093, USA