1. State Key Laboratory of Strength and Vibration of Mechanical Structures Xi'an Shaanxi 710049 China
2. School of Aerospace EngineeringInternational Center for Applied MechanicsXi'an Jiaotong University Xi'an Shaanxi 710049 China
3. School of Engineering and Applied SciencesKavli Institute for Bionano Science and TechnologyHarvard University MA 02138 USA