Research Article

Model Identification of Unobservable Behavior of Discrete Event Systems Using Petri Nets

Algorithm 1

Identification of an unobservable subnet.
Input: A net system
Output: A Petri net with
(1) , , , , ;
(2) wait until transition is observed;
(3) if then
(4)if then
(5); goto 2;
(6) else
(7) goto 13;
(8) end if
(9) else
(10) if ILPP 1 admits a solution then
(11); ; goto 2;
(12) else
(13) if ILPP 3 admits a solution and then
(14); ; ;
(15); ;
(16);
(17)goto 2;
(18)else
(19) error: cannot find a solution satisfying ILPP 3
(20)return
(21) end if
(22) end if
(23) end if