智能交通系统模型的算法分析与改进

对智能交通系统中的求路段平均速度和平均旅行时间的算法进行了改进,采用间接法对路段平均行驶时间进行估测和对最优路径进行选择。通过收集多点的检测数据,在采用两点速度逼近平均速度的方法的同时,引入改进的流量融合技术来对某一路段的平均速度进行估测。在求平均旅行时间时,考虑到各路段旅行时间相互关联的情况,通过构造一个时间相关的协方差矩阵来描述各路段之间的相关性,与传统的算法相比,在实时更新方面更具优势。

Analysis and Improvement of Algorithms for ITS Model

In this paper,some conventional algorithms are improved by using the indirect method.These algorithms are about mean velocity and traveling time in individual links of ITS model.In these algorithms,average velocity is estimated by introducing a renewed method of fusing traffic density and two extreme point velocities.Especially,traveling times on individual links are mutually correlated in practice.A time dependent covariance matrix is designed to quantify such a time-varying correlation relationship between each two individual links.The new algorithm is better than old one in real-time update.