为揭示交叉口车道的布设、交通流量、车辆所在时空位置等要素对直行车辆出口车道选择行为的影响,保障直行车流运行安全,运用专家知识和相关性分析确定了由最内侧直行车道中线偏移角、进口车道位置等10个影响因素组成的贝叶斯网络(Bayesi...为揭示交叉口车道的布设、交通流量、车辆所在时空位置等要素对直行车辆出口车道选择行为的影响,保障直行车流运行安全,运用专家知识和相关性分析确定了由最内侧直行车道中线偏移角、进口车道位置等10个影响因素组成的贝叶斯网络(Bayesian Network,BN)结构,采用数据驱动法进行了参数学习,建立了直行出口车道选择BN模型。经验证,模型的平均绝对偏差(Mean Absolute Error,MAE)、均方根误差(Root Mean Square Deviation,RMSE)分别为4.37%、4.96%,具有良好的精度。应用正向推理得到:影响直行出口车道选择的主要因素是进口车道位置、进出口车道数量匹配性、进出口车道选择不匹配比例、最内侧车道中线偏移角;引入情景分析法可有效预测进口车道平均流量等不同影响因素组合波动时出口车道利用率的变化,如直行车辆由最内侧进口车道驶入直行最内侧车道中线左偏移角为2°~4°的交叉口,在直行车流为>600~900辆/(h·道)、绿色信号倒数(Green Signal Countdown Display,GSCD)显示到达的条件下,选择最内侧出口道的概率为44.6%。研究结果为交通管理部门提供了直行出口车道选择的预测工具,为交叉口直行车流安全理论研究提供支持与参考。展开更多
To determinate the expressway capacity near a bus bay stop with an access, capacity models on the expressway near a bus stop with an access were developed on the basis of gap acceptance theory and queuing theory. Depe...To determinate the expressway capacity near a bus bay stop with an access, capacity models on the expressway near a bus stop with an access were developed on the basis of gap acceptance theory and queuing theory. Depending on a bus stop position to an entrance or an exit ramp, the capacity models were developed for four cases. Bus bay stops with overflow and bus bay stops without overflow were considered. A comparison of simulation experiment and model calculation was carried out. Results show that the suggested models have high accuracy and reliability, at bus arrival rate below 60 vehicles per hour(veh/h) or vehicle volumes at the entrance and the exit below 200 passenger cars units per hour(pcu/h), and there are no significant difference in the capacities for four cases. When bus arrival rate is above 240 veh/h, the capacities of all four cases will decline rapidly. With berth number increasing, the increasing of the capacities is no obvious for four cases. As the bus arrival rate and vehicle volumes at the entrance and the exit increase, bus stops located downstream of an entrance and upstream of an exit have a remarkably effect on the capacities. The latter case is much heavier than the former. Those results can be used to traffic design and optimization on urban expressway near a bus stop with an access.展开更多
文摘为揭示交叉口车道的布设、交通流量、车辆所在时空位置等要素对直行车辆出口车道选择行为的影响,保障直行车流运行安全,运用专家知识和相关性分析确定了由最内侧直行车道中线偏移角、进口车道位置等10个影响因素组成的贝叶斯网络(Bayesian Network,BN)结构,采用数据驱动法进行了参数学习,建立了直行出口车道选择BN模型。经验证,模型的平均绝对偏差(Mean Absolute Error,MAE)、均方根误差(Root Mean Square Deviation,RMSE)分别为4.37%、4.96%,具有良好的精度。应用正向推理得到:影响直行出口车道选择的主要因素是进口车道位置、进出口车道数量匹配性、进出口车道选择不匹配比例、最内侧车道中线偏移角;引入情景分析法可有效预测进口车道平均流量等不同影响因素组合波动时出口车道利用率的变化,如直行车辆由最内侧进口车道驶入直行最内侧车道中线左偏移角为2°~4°的交叉口,在直行车流为>600~900辆/(h·道)、绿色信号倒数(Green Signal Countdown Display,GSCD)显示到达的条件下,选择最内侧出口道的概率为44.6%。研究结果为交通管理部门提供了直行出口车道选择的预测工具,为交叉口直行车流安全理论研究提供支持与参考。
基金Project(2012CB723303)supported by National Basic Research Program of China
文摘To determinate the expressway capacity near a bus bay stop with an access, capacity models on the expressway near a bus stop with an access were developed on the basis of gap acceptance theory and queuing theory. Depending on a bus stop position to an entrance or an exit ramp, the capacity models were developed for four cases. Bus bay stops with overflow and bus bay stops without overflow were considered. A comparison of simulation experiment and model calculation was carried out. Results show that the suggested models have high accuracy and reliability, at bus arrival rate below 60 vehicles per hour(veh/h) or vehicle volumes at the entrance and the exit below 200 passenger cars units per hour(pcu/h), and there are no significant difference in the capacities for four cases. When bus arrival rate is above 240 veh/h, the capacities of all four cases will decline rapidly. With berth number increasing, the increasing of the capacities is no obvious for four cases. As the bus arrival rate and vehicle volumes at the entrance and the exit increase, bus stops located downstream of an entrance and upstream of an exit have a remarkably effect on the capacities. The latter case is much heavier than the former. Those results can be used to traffic design and optimization on urban expressway near a bus stop with an access.
