Abstract
The paper is dedicated to hierarchical Petri nets with application to design of control devices. It consists of two parts. The first part introduces a concept of simplifying analysis of flat Petri nets (we discuss analysis of reachability and liveness) by means of hierarchical decomposition. We present a class of subnets which can be replaced by the macroplaces. Further we describe properties of such decomposition and show, that analysis of the mentioned properties of a net can be reduced to the corresponding analysis of the elements of decomposition. A method allowing to obtain the decomposition is presented. The second part presents an approach to specification of a digital control system behavior by means of hierarchical Petri nets. We describe a model, called HPN, which has some of important properties, simplifying description of strongly reactive systems.
Highlights
Petri nets [1] present a mathematical model describing parallel asynchronous discrete systems
In the last part of the article we present a model of hierarchical Petri net which allows simple description of strongly reactive systems
A method of hierarchical decomposition of Petri abort(t) = true nets is discussed in this paper; theoretical results on properties of the decomposition are presented
Summary
Petri nets [1] present a mathematical model describing parallel asynchronous discrete systems. Hierarchical structures are required in many applications of Petri nets in system engineering; hierarchical description of a system simplifies greatly understanding of its functioning, its analysis, verification and implementation. The proposed method, being a combination of hierarchical and block decomposition, is simple and does not require exhausting of multiple variants; on the other hand, it allows selecting the subnets of complex structure. In the last part of the article we present a model of hierarchical Petri net which allows simple description of strongly reactive systems. A marking of a net is defined as a function M: P→{0, 1, 2,...} It can be considered as a number of tokens situated in the net places. The initial marking should be taken into account, so the condition is needed:
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
