1. Institute of Advanced Machinery and Design; Seoul National University; 599 Gwanak-ro, Gwanak-gu; Seoul; 151-744; Korea
2. Department of Mechanical Engineering; Seoul National University of Science and Technology; 172 Gongreung-2-dong, Nowon-gu; Seoul; 139-743; Korea
3. School of Mechanical and Aerospace Engineering, College of Engineering; Seoul National University; 599 Gwanak-ro, Gwanak-gu; Seoul; 151-744; Korea