�����ź����ȵķ������۷�����ͳ����֤

公交信号优先系统在投入使用以前要经过严格的测试分析。交通仿真虽然在这方面是一个很好的工具，但它往往需要大量的路网输入，数据采集以及模型校准等工作。而且，交通仿真模型的开发都是根据不同的项目“量身定做”，项目完成即被丢弃，很难再重复使用到其它项目上去。本文探讨用交叉口容量分析的方法来评价公交信号优先对公交车以及其它车辆的影响。就目前最常用的两种公交信号优先方法，即“绿信号先导”和“绿信号延长”展开分析，用大家熟知的韦伯思特的图形方法来诠释这两种方法对公交车辆和其它车辆交叉口延迟的影响.采用交通仿真对分析结果进行的统计验证表明,用分析方法得到的结论是可靠的。

An Analytical Approach to Evaluating Transit Signal Priority

Successful deployment of transit signal priority(TSP) systems requires thorough laboratory evaluation before field implementation.Traffic simulation is a powerful tool in this regard.However, it requires tremendous efforts toward network coding, data collection, and model calibration. Besides,simulation models tend to be project specific and the models developed for one project are often discarded upon the completion of that project.In this paper,it is shown that the impacts of two fundamental TSP strategies(early green and extended green)can be evaluated using an analytical approach.The impacts of the above two surategies on both the prioritized and the nonprioritized approaches are illustrated using graphical as well as analytical methods.A simulation study is then conducted for comparison analysis,followed by a statistical approach for the test of generality.