城市干线道路交通“拥挤态势指数”的确定

Determining Traffic State Evolution Index on Urban Arterial Road

为对道路交通拥挤随着时间发展演化情况作出准确客观的描述,本文研究了城市干线道路交通'拥挤态势指数'的确定方法.以定点检测数据为基础,从定性和定量两个角度分别定义了5个拥挤指标,并按时间顺序将它们排列成交通拥挤态势描述'时间序列'.在对上述时间序列使用多元统计'降维'后,使用R/S分析法计算各序列的Hurst指数.据此验证多个指标间的时间序列趋势一致性,找到既能从定性角度又能从定量角度进行综合评价的指标作为'拥挤态势指数'.最后,以上海南北高架东侧上11天的定点检测数据为例进行实证分析,确定了因子1作为'拥挤态势指数'.

To describe the traffic state evolution over time in an accurate and objective manner, this paper proposes the method to determine Traffic State Evolution Index on urban arterial road. Based on the fixedpoint data, five congestion indexes are defined from both quantitative and qualitative aspects. And they are arranged into＂time series＂in chronological sequence to reflect traffic state evolution. After these time-series＇ dimension are reduced by multivariate statistics method, the Hurst indexes are calculated using R/S analysis method. The results are utilized to test the consistence of time- series, and to find the synthetic indicator which can evaluate the status from two aspects of qualitative and quantitative as Traffic State Evolution Index. In the last section, the Loop Detector data from the eastern of Shanghai North-South expressway in 11days is taken as an example, and it is verified and concluded that factor 1 can be determined as Traffic State Evolution Index.