Sufficient and necessary conditions to guarantee deadlock-free scheduling for an extended S3PR with correlated resources

Abstract

ABSTRACTA deadlock prevention method is proposed for a special class of a system of simple sequential processes with resources (S3PR), where two kinds of interrelated resources exist such that the processing ability of each resource kind equals 1. The extended S3PR with correlated resources (ES3PR-CR) Petri net was first characterized and defined, and modeling procedures presented based on the Petri nets. Secondly, the sufficient and necessary conditions were presented to realize deadlock-free scheduling. By defining the maximal setting boundary for deadlock-free scheduling, a net-structure-based algorithm for resolution was proposed, as long as the initial marking of the Petri net was not greater than any one in , the controlled system never entered a deadlock state. This guaranteed that a controlled system had no deadlock while scheduling. Finally, a locomotive dispatching system in an underground coalmine was analyzed as an example to illustrate the validity of the proposed method. Compared with existing literature results, the proposed deadlock prevention method was net-structured and could be realized without any controller places, which provided a smaller size.