1. School of business and technology management, College of business; Korea Advanced Institute of Science and Technology, KAIST Bldg. N22, 291 Daehak-ro; Yuseong-gu Daejeon 34141 Republic of Korea
2. Department of active aging industry; General graduate school, CHA university, 120; Haeryong-ro, Pocheon-si Gyeonggi-do 11160 Republic of Korea