Empiric alanalysis on fractal characteristics of freeway traffic flow
Research on the fractal characteristics of freeway traffic flow evolution is helpful to deeply understand the evolution rule of freeway traffic flow system,which can provide the theoretical foundation for forecasting and controlling freeway traffic flow.In this paper,the statistical approaches and complex network visualization technology are applied to investigate the presence of fractal characteristic in the freeway traffic time series.Firstly,by calculating the Hurst exponent and V-statistic through rescaled range analysis,we find the values of the Hurst exponent are greater than 0.5,and the V-statistic curve has an upward trend,which indicate that the time series of freeway traffic are fractal with self-similarity and long-range dependence.Then,based on the visibility algorithm,we convert the time series into complex networks and calculate the topology parameter of them,the result further shows that freeway traffic flow time series is fractal sequence.The authors also find the average path length increases with the network scale was logarithmic,which shows that the network has the feature of small-world.Empirical analysis results can be used as a very important reference to select the time scale and the length of predicting for forecasting and controlling freeway traffic flow.Research results in this paper can provide new ideas and methods for investigating the complexity of freeway traffic flow evolution.
国家科技期刊平台
NSTL
万方数据
维普
