JOURNAL OF THE KOREAN PHYSICAL SOCIETY, vol. 49, no. 1, page. 31 - 36, 2006-07
JOURNAL OF THE KOREAN PHYSICAL SOCIETY, vol. 48, page. S179 - S185, 2006-02
JOURNAL OF THE KOREAN PHYSICAL SOCIETY, vol. 48, page. S192 - S196, 2006-02
PHYSICAL REVIEW E, vol. 72, no. 6, 2005-12