Time Petri Nets And Their Applications In Simulation System Conceptual Modeling

With the modeling and simulation technology being widely used in variousindustries, Petri nets are gaining more and more attention as a graphical modelinglanguage. The proposition of time Petri nets, undoubtedly, provides an accuratedescription means for the discrete-time dynamic process of a simulation system. Notonly does it can describe the logical relationship s among events, such asasynchronousness and concurrency, it can also reflect the time-related information,which is the functional expansion of the basic Petri net theory. With the increasingcomplexity of a simulation system, the role of the conceptual model is alsoincreasingly critical, which already becomes one of the primary tasks of the systemmodeling and simulation research. The paper is carried out from the three aspects,theoretical methods, tool design and implementaion, and application example:Firstly, the standard Petri net theory is described. The definition, enablingconditions and fir ing of standard Petri nets are illustrated in detail. After that, thepaper presents the definition of time Petri nets, with their enabling and fir ingconditions being given too. It then proposes a simulation algorithom of time Petrinets and discusses thesampling methods for the selections of time and transtions tobe fired. The simulation algorithom is verifed with a simple example.Secondly, the paper conductes the design of time Petri net simulation tool. Itbriefly introduces the Snoopy modeling tool and designs the simulation tool in threemodules: information export module, the simulation algorithm implementationmodule and simulation plot drawing module. The tool covers the entire process ofmodeling and simulation, which is used for the study of the application example inthe next part.Finally, the application of time Petri nets in simulation conceptual modeling isdiscussed. The paper discribes the basic concepts of the simulation conceptualmodel, such as the model composition, development process and existing modelinglanguages. The modeling method by appling time Petri nets to the conceptual modelis described in detail. The paper then presents an application example of a commandcontrol system, and then builds a time Petri net conceptual model for it and carriesout some simulation analyses.In conclusion, based on the standard Petri net theory and the study of theiranalysis methods, the paper proposes a time Petri net simulation algorithm, anddesigns a simulation tool for time Petri nets. The paper builds a time Petri netconceptual model for a command control system, and carries out some analyses forit. The research work in this paper extends the basic Petri net theory and its application.