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4. Example of renting agency with vicinity respecting morphism

In this and the next sections, we will present two examples of Petri net morphisms. One focuses on the structural properties of Petri nets with vicinity respecting morphism, the other emphasizes both .the structural and behavioral properties of Petri nets with generał morphism.

The two examples we are going to present are renting agency system model and Petri net implementation of the Peterson’s mutual exclusion algorithm. In both examp!es, we will give a relatively detailed Petri net graph representation of the system being modeled, then obtain abstractions of the system using vicinity respecting morphism or generał morphism. Moreover, we will simulate the models of Peterson’s algorithm using Renew [RE].

4.1    Introduction to Renew

Renew is impiemented by a group in Germany. It is a Java-based high-level Petri net Simulator that provides a flexible modeling approach based on reference net [RE]. It features a relatively clean language design, good portability, and a powerful set of system libraries.

4.2    Renting agency example

This example concerns the modeling of a car hire sen/ice, seen from three different perspectives: the customer perspective, the assurance company perspective and the car hire service perspective.

The customer perspective emphasizes the different possible States of the customer, with the car hiring service being viewed as some form of transition with which customers interact. The emphasis of the assurance company perspective