公交车辆在线路运行中受到多种随机因素的影响,如道路交通状况、站点乘客上下车等,导致同一线路公交车辆的车头时距产生较大波动,降低公交车辆的运载效率及服务质量。滞站策略能够有效保持公交车辆车头时距的稳定性。鉴于随机因素对公交线路的影响,将公交滞站问题看成多阶段随机决策过程,利用随机决策理论和动态规划的最优化原理,确定出每辆车到达控制点时的最佳滞留时间,使整个线路车头时距波动方差的期望值最小化,进而得到最佳公交车辆滞站决策方案。通过实例分析,随机决策滞站策略,能够显著降低乘客的平均等待时间,提高公交服务质量,且在稳定性及抗干扰性具有明显优势。
Buses are affected by various random factors when running along the route, such as traffic conditions and passengers boarding and alighting. Therefore, the bus headways fluctuate strongly leading to low transit effi- ciency and service quality. Holding strategy can help to maintain the headway stability effectively. In consideration of the randomness of factors, the transit holding problem is described as a multi-stage stochastic decision process. Aiming to minimize the expected Variance of bus headway deviation, the decision-making theory and dynamic pro- gramming are used to determine the optimal holding time when each bus arrives at the control point. Compared to other holding strategies through a case study, the proposed method can reduce the average waiting time and has obvious advantages on stability and anti-turbulence.