Research On The Models Of Flight Delays Chain Reaction Based On Petri Net

As the rapid development of the civil aviation, flight delays have become a hot point which has puzzled the civil aviation department and the vast travellers. There is a connective relationship among the flights due to one airplane might implement a few flights. Thus the upstream flight which delayed may propagate many downstream flights which in the connective relationship, and cause flights delay chain reaction. High-level Petri net is a graphical tool and mathematical tool which is suited for system description and analysis. And it is effectively applied to the workflow issues of parallel and asynchronous. So high-level Petri nets and models are applied to flight delays chain reaction and propagated analysis in this paper, which has important theoretical significance and practical value. Main efforts include:Pointed at the flights chain of airlines, first of all, based on the theory of Petri nets, a timed Petri nets model was established for one airplane to implement a few flights. A propagated analysis algorithm was given to judge whether the lower reaches of the initial delayed airport delay when the initial delayed time was known, and calculated the delayed time; the second, based on the theory of colored Petri nets and timed Petri nets, a colored Petri nets model was used for airplanes taking off from one airport to implement a few flights. And a colored-timed Petri nets model was established for multi-airports and multi-flights. A propagated analysis method for the flight delay was also given. Pointed at the in-and-out queue of aircrafts at the airport, a colored-timed Petri nets model was established for the run of airplanes in airport based on the critical resources. A timed Petri net model for propagated dalays between the two aircrafts in non-priority aircraft group was established and also another timed Petri net model for propagated dalays between the two aircrafts in priority aircraft group was established. Theoretical calculation formulas for the average propagated dalay time of aircrafts and total value of propagated dalay time of aircrafts were given based on the timed Petri net models. It provided theoretical and technical support for the early warning of flight delays and propagated analysis system with the characteristics of China's civil aviation.