The Study On Traffic Congestion Control And Nonlinear Densitywave Based On Intelligent Transport Systems

Traffic is a major issue of public concern. In recent decades, in order to explore the internal mechanism oftransport phenomena, people has established a number of traffic flow models by analysing the traffic flowcharacteristics through different views. In this dissertation, based on the coupled map car-following model,considering the performance of Intelligent Transport Systems (ITS), an improved traffic congestion controlmethod is proposed. In addition, based on the lattice hydrodynamic model, the corresponding theoreticalanalysis and numerical simulation of several lattice hydrodynamic model are performed, focusing on thenonlinear density waves in the lattice hydrodynamic model.The main contents are as follows:I. The traffic congestion control, considering the backward effect in the coupled map car-following modelBy setting delayed-feedback control, Konishi et.al presented a control method to suppress the trafficcongestion in the coupled map car-following model under open boundary. Based on the pioneer work and theperformance of ITS, we proposed an improved traffic congestion control method, considering the relativespeed of the current car and the nearest one behind it. Using feedback control theory, the conditions of notraffic jam in the controlled system are given when the lead-vehicle is changing. Meanwhile, we show thenumerical simulation.II. Four different versions of lattice hydrodynamic models are compared and summarized, and thegeneral solution of the modified Korteweg-de-Vries (mKdV ) equations is givenBased on the original lattice hydrodynamic models proposed by Nagatani et.al., we get the neutralstability conditions by linear analysis, and the phase diagram in the density-sensitivity space which presentingstable region and unstable region is given by numerical simulation. On this basis, mKdV equations describingthe kink-antikink soliton waves near the critical point, are derived by reductive perturbation method.Furthermore, the general solution of the density wave in the different versions of lattice hydrodynamic modelsis derived. And we compare the result to the pioneer work. Finally, the fourth kind of the latticehydrodynamic models is simulated.III. Lattice hydrodynamic model with bidirectional pedestrian flow of non-linear density wavesTian Huan-huan et.al proposed the lattice hydrodynamic model with bidirectional pedestrian flow. Forthis extended lattice hydrodynamic model, we apply the general solution of the mKdV equation that given inthe above to the nonlinear analysis. Not only the process is simplified, the results are consistent with theknown results. It indicates that our general solution has universal applicability and replicability. In addition, we get the Korteweg-de-Vries (KdV) equation desribing solitary wave near the neutral stability lines, the solutionof the KdV equation is calculated. Thus, the description of nonlinear characteristics is further improved.