Petri Nets III
Wednesday, October 26, 2005
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Review -Timed Petri Net
 Time
can be associate with places, arcs, or
transitions. There are real life examples where
time is associated with more than one type of
petri net parts. Generally(in this course), we’ll
associate time with each transitions.
 This delay time can be deterministic or
probabilistic.
 Number of servers produce different outcomes.
 Timed Petri Net with Multi-Server / Infinite
Server
D i = Ai + σ
 Timed Petri Net with a Single Server
Di = max(Di-1, Ai) + σ
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
Clarification
Not a conflict
After a firing, p1 and p
both are going to get a
token each.
p1
p2
Conflict
t1 and t2 are both ready to
fire but the firing of one of
them leads to disabling of
the other transitions.
t1
t2
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Exercises

Draw and simulate fig. 4.41

Draw and simulate following situation:
John and Mary are sharing one toy between them.
John plays with the toy and then hands it to Mary.
Meanwhile, John may pick up another series of
toys, but each time he is unable to give a toy to
Mary until she tells him she finished with the toy,
and can now get the next one.
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