Research On Obtaining Vehicle OD Matrix And Dynamic Traffic Assignment Simulation Based On License Plate Date

With the development of the Intelligent Transportation System(ITS),the information level of transportation management is increasingly higher.Full coverage of intelligent monitoring and recording system for vehicles has been basically achieved at intersections of urban roads in China,collecting data of millions of license plates daily.These data,mainly applied by traffic administration for settling illegal activities,are seriously wasted with no further data mining.Based on license plate data collected in Tangshan,this paper obtained OD matrix,and carried out in-depth data analyzing and the simulation of dynamic traffic assignment via Vissim.The main research work contains as follows:First,the license plate data of Tangshan was analyzed and pre-processed.The reliability of the data was confirmed for follow-up studies.Transportation time features in Tangshan were obtained to help select the time interval for research.Measures to deal with the absence of registration data were put forward,together with methods for unusual data processing.Second,the approach to obtain OD matrix based on license plate data was presented.Taking a road network with 20 intersections in Tangshan as an example,license plate data were analyzed via SPSS and Excel VBA,and then the OD matrix among intersections in the road network were achieved.Trajectory tracking method was applied to verify the reliability of obtained OD data.Then,the paper introduced the travel time distribution acquired via SPSS on the basis of license data mining.By referring to the length of travel time,the division of traffic zone was obtained,and was evaluated according to three criteria: modularity,scale,divisibility.This paper aims at providing a new idea for OD investigation at the transportation planning level by clustering OD matrix between intersections to obtain OD matrix in specific traffic zone.At last,through analyses of the dynamic traffic assignment model and multiple simulated iteration on Vissim,the route choice of travelers was simulated.By applying the modified Logit model and though repeated simulating operation,the convergence results of the dynamic traffic assignment were obtained.Combined with real examples,the convergence results of the dynamic traffic assignment model were obtained after hundreds of times of simulation runs on basis of the road network modeling on Vissim and a detailed parameter calibration.Analysis of the results verified the model's effect that overall delay at intersections in the road network were significantly reduced.The simulation research based on Vissim in this paper has explored new approaches for the application study of the dynamic traffic assignment theory.