The state equation of Petri net for the LD program. - Gi-Bum Lee; Jin S. Lee (SMC, 2000)

The U-Circuit Structure in Ordinary Peri Net. - Gi-Bum Lee; ZanDong Han; Jin S. Lee (FSKD, 2002)

Generalized state equation of Petri Nets with priority. - Gi-Bum Lee; ZanDong Han; Jin S. Lee (Int. J. Intell. Syst., 2003)

Automatic generation of ladder diagram with control Petri Net. - Gi-Bum Lee; ZanDong Han; Jin S. Lee (J. Intell. Manuf., 2004)

Token Transfer Structures between V-path and U-circuit. - Gi-Bum Lee; Jeong-Heon Heo; ZanDong Han; Jin S. Lee (IJCCI (ICFC-ICNC), 2010)