城市快速路网行程时间计算与最优路径选择算法

为提高城市快速路网的整体功能和运行效益，利用实时动态交通数据，根据动态交通因素对路段通行时间的影响，将城市快速路网划分为非拥塞和拥塞两种情况，基于安全停车距离和剩余通行能力，分别计算了两种情况的路段通行时间，提出了以行程时间最短为目标的城市快速路网行程时间计算与最优路径选择算法.将该算法应用于西安城市快速路网进行案例分析，结果表明:该算法的最优路径计算结果与实际相符，误差在15%以内；最优路径的距离约为最短路径的1.84倍. 

Travel Time Computation and Optimal Path Selection Algorithm of Urban Expressway Network

In order to improve the overall functionalities and utilities of urban expressway network, a travel time computation and optimal path selection algorithm was proposed for urban expressway network by utilizing the dynamic traffic data acquired along expressway segments in real time. According to the influential patterns of dynamic traffic factors on travel time, this algorithm classifies the urban expressway network into non-jammed and jammed segments, and computes their travel time using safe stop distance and residual traffic capacity, respectively. The minimum overall travel time is taken as optimization criteria for optimal path selection of urban expressway network. As a case study, this algorithm was applied to Xi'an urban expressway network. The analysis results show that the optimal paths selected are in good agreement with the practical cases. The coincidence rate error is kept within 15%, and the distance of optimal path is about 1.84 times that of the shortest path.