Refinement Of Object-Oriented Petri Net And Its Application In System Modeling

Object-oriented Petri net(OOPN),combining the advantages of object-oriented technology and Petri net,can not only intuitively describe the object and relationships of the objective world,but also has a strict definition of mathematical norms.It has become an important tool for academic and industrial to research system modeling.However,as the scale and complexity of the systems needed to be analyzed such as embedded system and flexible manufacturing system continue to expand,the problem of"explosion"in state space is still prominent when using object-oriented Petri net to model on them.How to deal with this problem and apply OOPN to the modeling of different systems sufficiently has always been the focus of academic research.In this paper,aiming at the modeling problem of the system with obvious module or function division,such as intelligent garbage classification,the conclusion is drawn that the object-oriented Petri net and refinement method can be used to solve this kind of problem.The main research contents of this paper are as follows:(1)According to the characteristics of OOPN net,the corresponding properties of Petri net are extended,and then the definition of liveness and boundedness of OOPN net system and the correlation matrix method for liveness analysis are proposed.(2)The concepts of external place and internal place in OOPN network are defined.And it put forward the concepts of class network,object network,gateway type subnet and corresponding closed network system related to refinement operation.(3)Three kinds of refinement operation methods of OOPN network are proposed--class net refinement,object net refinement and gateway subnet refinement.This paper mainly uses the above methods to refine some external place(p~o),internal place(p~+)and gateway(G)in OOPN network,updates the formal representation of network model on the basis of the original symbol representation of network,and gives the corresponding legend illustration.(4)After refining the original network system with the methods of object network refinement,class net refinement and gateway subnet refinement,the liveness and boundedness preservation theorems of the target network system are obtained,and the corresponding proofs are given.(5)Based on different OOPN network refinement operation,different systems are modeled and applied.The hospital telemedicine system was modeled based on the object network refinement method,and the sales business process was modeled based on the gateway subnet refinement method,which was illustrated by the graphic method.This section mainly introduces the modeling of intelligent garbage classification system based on class net refinement operation.A rough model of the system is established firstly,and then a detailed and complete OOPN network system model is established by using the class net refinement method.During this process,useing Tina simulation tool and math's method of Petri net to analyze the properties of each OOPN network model obtained.It not only verifies the feasibility and effectiveness of the method,but also alleviates the state space"explosion"problem of OOPN network system to a certain extent.Finally,a summary of the whole work is made,and the future research is prospected.