1. Graduate Student, Dept. of Mechanical and Aerospace Engineering, Seoul National Univ., 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea.
2. Researcher, Korea Aerospace Industries, Ltd., 78, Gongdanro 1-ro, Sanam-myeon, Sacheon, Gyeongsangnam-do 52529, Republic of Korea.
3. Professor, Dept. of Mechanical and Aerospace Engineering, Institute of Advanced Aerospace Technology, Seoul National Univ., 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea (corresponding author).