高速公路交通流混沌特性研究

Chaos Characteristics of Expressway Traffic Flow

提出了一种基于Zuo Binwu矩阵算法的判别交通流混沌的最大Lyapunov指数改进算法,并用这种改进算法和功率谱法研究了高速公路实测交通流的混沌问题。绘制了高速公路交通流实测的时间序列的功率谱曲线。通过分析这种车头间距的功率谱曲线,可以明显地观察到交通流频谱出现了噪声和宽峰的变化。应用最大Lyapunov指数改进算法计算这些时间序列的最大Lyapunov指数,用它判定实测交通流是否存在混沌现象。结果表明高速公路实测交通流中存在混沌现象。最后对结果作了分析,得出了对于研究与应用交通流有益的结论。

An improved largest Lyapunov exponents＇ algorithm is put forward for rapid identification of chaos in traffic flow based on Zuo Binwu＇s algorithm. The chaos of expressway traffic flow is studied with the improved largest Lyapunov exponents＇ algorithm and the power spectrum. The power spectrums of the time serials of traffic flow are illustratecd. Through the analysis of the power spectrum of the headway, it is clear that there are variations of noise and wide apices. The largest Lyapunov exponents of the time series of traffic flow are computed and used to identify the chaos in the expressway traffic flow. The results prove that chaos in the expressway traffic flow do exist. The results are analyzed. Finally, useful conclusion of the study and application of traffic flow is presented.