Conference of KITE, Seoul Univ., page. 706 - 709, 1989-11-18
Wave and Laser Conference of KITE, ETRI, page. 210 - 213, 1989-02-01
Conference of KITE, page. 697 - 700, 1989-01-01
1987 Electrical Meeting semiconductors and CAD meeting of KIEE, page. 247 - 250, 1987-05-01