1. JUNGHEE HAN(corresponding author), Department of Software, Communication and Engineering, Hongik University, Room B 306-2 Sejong-ro, Jochiwon-eup, Sejong 30016, Korea.
2. SUNGHOON CHUNG, Graduate School of Technology and Innovation Management, Hanyang University South Korea, South Korea.
3. HEEYOUNG JANG, Korea Institute of Industrial Technology, Gyeongsangbuk-do, South Korea.