1. Department of Statistics, Daegu University, Gyeongsan-si 38453, Gyeongsangbuk-do, Republic of Korea
2. Korea Institute of Civil Engineering and Building Technology, 283, Goyangdae-ro, Ilsanseo-gu, Goyang-si 10223, Gyeonggi-do, Republic of Korea
3. Hydro-Power Research and Training Center, Korea Hydro & Nuclear Power Co., Ltd., Gyeongju-si 38120, Gyeongsangbuk-do, Republic of Korea