1. Railway Interoperability Research Team, Korea Railroad Research Institute 360-1, Woram-dong, Uiwang-si, Gyeonggi-do 437-757, Korea
2. Department of Aerospace Engineering, Korea Advanced Institute of Science and Technology 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701, Korea
3. Department of Aerospace Engineering, Korea Advanced Institute of Science and Technology 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701, ,