In many Chinese cities,motorized vehicles （M-vehicles） move slowly at intersections due to the interference of a large number of non-motorized vehicles （NM-vehicles）.The slow movement makes a part of M-vehicles fa...In many Chinese cities,motorized vehicles （M-vehicles） move slowly at intersections due to the interference of a large number of non-motorized vehicles （NM-vehicles）.The slow movement makes a part of M-vehicles fail to leave intersections timely after the traffic signal tums red,and thereby conflicts between vehicles from two directions occur.The phenomenon was analyzed graphically by using the cumulative vehicle curve.Delays in three cases were modeled and compared：NM-vehicle priorities and M-vehicle priorities with all-red intervals unable to release all vehicles,and longer all-red intervals ensuring release all vehicles.Marginal delays caused by two illegal behaviors that occasionally happened in mixed traffic intersections were also investigated.It is concluded that increasing the speed of M-vehicles leaving intersections and postponing the entering of NM-vehicles are the keys in mathematics,although they are uneasy in disordered mixed traffic intersections due to a dilemma between efficiency and orders in reality.The results could provide implications for the traffic management in the cities maintaining a large number of M-and NM-vehicles.展开更多
道路阻抗是交通分配和路网规划中的重要参数,是路网属性抽象的重要内容之一。为给道路阻抗函数研究提供新思路和新方法,更好服务于交通分配和路网规划,针对路阻函数的研究背景及现实意义,从路阻函数研究方法和影响因素两方面综合对比分...道路阻抗是交通分配和路网规划中的重要参数,是路网属性抽象的重要内容之一。为给道路阻抗函数研究提供新思路和新方法,更好服务于交通分配和路网规划,针对路阻函数的研究背景及现实意义,从路阻函数研究方法和影响因素两方面综合对比分析各种路阻函数模型的优缺点,分析得出既有研究多以美国联邦公路局(Bureau of Public Roads,BPR)函数为基础,针对BPR函数本身缺陷进行优化,或加入其他影响路阻的因素进行优化。在此基础上,总结得出目前路阻函数研究中存在不重视数据采集、函数内参数不可靠、函数适应性不强等问题。最后,对未来研究方向进行了展望,未来可应用车联网、自动驾驶等前沿技术采集数据,应用大数据和人工智能算法提高参数可靠度,提出适用于自动驾驶的路阻函数,制定路阻函数适应性标准,扩大路阻函数应用范围。展开更多
基金Project(2012CB725403)supported by the National Key Research Program of ChinaProject(71131001)supported by the National Natural Science Foundation of ChinaProject(2012JBM064)supported by the Fundamental Research Funds for the Central Universities of China
文摘In many Chinese cities,motorized vehicles （M-vehicles） move slowly at intersections due to the interference of a large number of non-motorized vehicles （NM-vehicles）.The slow movement makes a part of M-vehicles fail to leave intersections timely after the traffic signal tums red,and thereby conflicts between vehicles from two directions occur.The phenomenon was analyzed graphically by using the cumulative vehicle curve.Delays in three cases were modeled and compared：NM-vehicle priorities and M-vehicle priorities with all-red intervals unable to release all vehicles,and longer all-red intervals ensuring release all vehicles.Marginal delays caused by two illegal behaviors that occasionally happened in mixed traffic intersections were also investigated.It is concluded that increasing the speed of M-vehicles leaving intersections and postponing the entering of NM-vehicles are the keys in mathematics,although they are uneasy in disordered mixed traffic intersections due to a dilemma between efficiency and orders in reality.The results could provide implications for the traffic management in the cities maintaining a large number of M-and NM-vehicles.
文摘道路阻抗是交通分配和路网规划中的重要参数,是路网属性抽象的重要内容之一。为给道路阻抗函数研究提供新思路和新方法,更好服务于交通分配和路网规划,针对路阻函数的研究背景及现实意义,从路阻函数研究方法和影响因素两方面综合对比分析各种路阻函数模型的优缺点,分析得出既有研究多以美国联邦公路局(Bureau of Public Roads,BPR)函数为基础,针对BPR函数本身缺陷进行优化,或加入其他影响路阻的因素进行优化。在此基础上,总结得出目前路阻函数研究中存在不重视数据采集、函数内参数不可靠、函数适应性不强等问题。最后,对未来研究方向进行了展望,未来可应用车联网、自动驾驶等前沿技术采集数据,应用大数据和人工智能算法提高参数可靠度,提出适用于自动驾驶的路阻函数,制定路阻函数适应性标准,扩大路阻函数应用范围。
