| OD matrix plays an important role in the transport system design, operation andmanagement process. OD matrix elements mean traffic between the trip start and end. Thewhole OD matrix contains the spatial distribution characteristics of traffic of all traffic cells.Transportation planning techniques, traffic control techniques and traffic guidancetechniques all need the OD matrix data. OD matrix can be used to calibrate trafficforecasting models, adjust the traffic control strategies, plan travel routes and analyze landuse policies. In addition, OD matrix can reflect the distribution of traffic characteristics, soid can be used as the input information of the traffic simulation model.In previous studies, people mainly collected OD matrix manually, such as householdsurveys, telephone surveys, postal surveys, staff surveys. In the investigation process forOD matrix, the space involved is usually larger, so the artificial ways need to consumelarge amounts of manpower and material resources. With the rapid development of trafficinformation collection techniques, we need more economical and more effective methodsto collect OD matrix.Static OD matrix is usually used in the field of transport planning, with the graduallyserious traffic problems, dynamic OD matrix is very important. Dynamic OD Matrix canhelp traffic guidance system to develop the traffic guidance strategies, and help trafficcontrol system to develop the traffic control strategies.For the problems of existing research methods, this paper designed a dynamic ODmatrix estimation method based on dynamic traffic assignment using traffic flow parameterdata, and studied the following three aspects:(1) The acquisition method of a priori OD matrixExisting dynamic OD matrix estimation methods need to known historical OD matrix.On this basis, a priori OD matrix is determined to estimate dynamic OD matrix. At present,there are little methods for obtaining the priori OD matrix, so this paper designed a prioriOD matrix collection methed for obtaining the priori OD matrix based on the mobile phonepositioning data. Firstly, the characteristics of the mobile location technology areintroduced. Then the construction method of OD set, the extraction method of a single ODand the expansion method of OD matrix were designed in succession.(2) Traffic Assignment Model The traffic assignment is not considering the impact on the traffic assignment resultsof the relationship between the traffic managers and traffic travelers, so this paper designeda traffic assignment model based on the Steinberg Game. Firstly, a basic model of trafficassignment was designed, and then the determination method of model parameters wasdesigned. Lastly the solution algorithm of traffic assignment models was designed.(3) Dynamic OD matrix estimate ion modelEstimation dynamic OD matrix is a nonlinear problem, so it is difficult to designmodel. The current dynamic OD matrix estimation method effect is not ideal, so this paperdesigned a dynamic OD matrix estimation model and the genetic tabu search algorithm wasused to solve the stimation model. In addition, the prediction method of dynamic ODmatrix was designed.The effect of the estimation method for dynamic OD matrix was validated usingtraffic simulation technologies, and reached the following conclusions:(1) For the greater weight of observed flow, and smaller weight of OD needs, theestimated effect is better;(2) For the higher accuracy of a priori OD, the estimated effect is better;(3) Search space is too large or too small, the estimation error of the model increases;(4) For the more smooth traffic, the estimated effect is better;(5) The estimated length of time affects he estimated effect;(6) The observation time interval affects he estimated effect.Although the above factors will have a certain impact on dynamic OD matrixestimation results, the dynamic OD matrix estimation results is better than the priori ODmatrix, it is shows that the model for dynamic OD matrix designed in this paper iseffective.
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