Affiliation: | 1. Sungkyunkwan University, #324, Business Building, 53 Myeongnyun-dong, 3-ga, Jongno-gu, Seoul 110-745, Republic of Korea;2. HyupSung University (HSU), Distribution Management Department, Business Management College, # 14 Sang-ri, BongDam-eup, HwaSung-City, KyungKi-do 445-745, Republic of Korea;3. Sogang University, Service Systems Management & Engineering, Graduate School of Business, #1, Shinsu-dong, Mapo-gu, Seoul 121-742, Republic of Korea |