On possibilistic timed safe Petri nets
Sandra Aparecida Sandri, Janétte Cardoso · International Journal of Intelligent Systems · 1999
The first goal of this work is to extend a model of Timed Safe Petri Nets to allow the treatment of preference between transitions. In the proposed Possibilistic Timed Safe Petri Net, we attach a duration to each transition, which can be precise, imprecise, or fuzzy, accounting for the maximal amount of time in which that transition can be completed once fired, and we attach a possibility degree to each arc between a place and a transition, to account for the preference of this transition in relation to the other transitions going out of that place. The second goal of this work is to address the problem of the management of incomplete information in the proposed model, what makes it possible to order the most plausible marking at a given moment of time. In particular, we investigate a new way to represent and deal with uncertain markings. Namely, we find all possible precise markings compatible with the uncertain marking, and attach to each one a weight accounting to the possibility of it being the real marking. Then the Petri net is dealt with as with precise markings, but with special operations performed with the weights. © 1999 John Wiley & Sons, Inc.