【摘 要】
：
对于高峰期发生的小型突发事件,应急车辆优先通行可能对路网造成强负外部性,同时为保证应急车辆优先通行而采取的信号协调策略可能导致路径选择不可靠.因此,提出1种基于双层规划模型的应急车辆优先通行策略,综合考虑应急车辆的时效性以及交通系统的运行效率.路径选择受路径长度等物理条件以及交通状态的影响,信号控制改变车道通行能力和上下游流量,进而改变路网状态.以车道组饱和度作为表征路网状态的参数,并以此联系路径选择与信号控制,进而构建应急车辆优先通行的双层规划模型.具体地,上层目标为应急车辆行程时间最短以保证应急车辆出
【机 构】
：
中山大学智能工程学院 广州 510006;中山大学广东省智能交通系统重点实验室 广州 510006;中山大学智能工程学院 广州 510006;中山大学广东省智能交通系统重点实验室 广州 510006;
论文部分内容阅读
对于高峰期发生的小型突发事件,应急车辆优先通行可能对路网造成强负外部性,同时为保证应急车辆优先通行而采取的信号协调策略可能导致路径选择不可靠.因此,提出1种基于双层规划模型的应急车辆优先通行策略,综合考虑应急车辆的时效性以及交通系统的运行效率.路径选择受路径长度等物理条件以及交通状态的影响,信号控制改变车道通行能力和上下游流量,进而改变路网状态.以车道组饱和度作为表征路网状态的参数,并以此联系路径选择与信号控制,进而构建应急车辆优先通行的双层规划模型.具体地,上层目标为应急车辆行程时间最短以保证应急车辆出行的时效性,下层目标为信号控制对交通系统的社会车辆效益最大,采用改进的前N条最短路径多重标号算法求解.算例结果表明:相较于传统方案,应急车辆行程时间增加8.7％,对社会车辆的延误降低261％,即应急车辆每降低1％的行程时间以交通系统增加30％的延误为代价.该方案能够以较小的应急车辆延误为代价降低高峰期交通系统较大的延误.
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