1. Department of Mechanical Engineering (Integrated Engineering Program) Kyung Hee University 1732, Deogyeong‐daero, Giheung‐gu Yongin‐si Gyeonggi‐do 17104 Republic of Korea
2. Department of Mechanical and Aerospace Engineering Seoul National University Gwanak‐ro 1, Gwanak‐gu Seoul 08826 Republic of Korea