A petri net approach to the modelling and analysis of flexible manufacturing systems

In this paper we present an approach for modelling and analyzing flexible manufacturing systems (FMSs) using Petri nets. In this approach, we first build a Petri net model (PNM) of the given FMS in a bottom-up fashion and then analyze important qualitative aspects of FMS behaviour such as existence/absence of deadlocks and buffer overflows. The basis for our approach is a theorem we state and prove for computing the invariants of the union of a finite number of Petri nets when the invariants of the individual nets are known. We illustrate our approach using two typical manufacturing systems: an automated transfer line and a simple FMS

HelpDez : colored-Petri-net-based hypermedia help system designer

This paper describes HelpDez, a colored-Petri-net-based approach for the design, simulation, and construction of hypermedia help systems. The storage model, system capabilities, and user interface model of a hypermedia help system are examined. Colored Petri nets are chosen to model hypermedia help systems due to their graphical expressiveness and their applicability to concurrent, asynchronous systems. Also, they make it easy to carry out general validations using previously developed analysis techniques. Furthermore, colored Petri nets allow concurrent browsing paths of a hypermedia help system to be described by a common subnet, without losing the ability to distinguish between them. A formal definition of the HelpDez model based on the colored Petri nets is presented . This model represents the structural properties of the help information (text, graphics, and sound), as well as specifications of the execution semantics associated with hypermedia help systems. The graphical representation of the colored Petri nets provides a powerful tool for specification of the information users can see and hear simultaneously when a hypermedia help system is executed

On the invariants of coloured Petri Nets

In this paper, we develop a theorem that enables computation of the place invariants of the union of a finite collection of coloured Petri Nets when the individual nets satisfy certain conditions and their invariants are known. We consider the illustrative examples of the Readers-Writers problem, a resource sharing system, and a network of databases and show how this theorem is a valuable tool in the analysis of concurrent systems