Transport system is a time-varying, huge and complex system. In order to have the traffic management department make pre-appropriate traffic management measures to adjust the traffic management control program, and re...Transport system is a time-varying, huge and complex system. In order to have the traffic management department make pre-appropriate traffic management measures to adjust the traffic management control program, and release travel information to travelers, to provide optimal path options to ensure that the transport system operates efficiently and safely, we have to monitor the changing of the state of road traffic and to accurately evaluate the state of the traffic, then to predict the future state of traffic. This paper represents the construction of the road traffic flow simulation including the logical structure and the physical structure, and introduces the system functions of forecasting system in Beijing.展开更多
Considering both the high complexity of urban traffic flow systems and the bounded rationality of travelers,providing traffic information to all travelers is an effective method to induce each individual to make a mor...Considering both the high complexity of urban traffic flow systems and the bounded rationality of travelers,providing traffic information to all travelers is an effective method to induce each individual to make a more rational route-choice decision.Within Advanced Traveler Information System(ATIS)working environment,temporal and spatial evolution processes of traffic flow in urban road networks are closely related to strategies of providing traffic information and contents of information.In view of the day-to-day route-choice situations,this study constructs original updating models of the cognitive travel time of travelers under four conditions,including not providing any route travel time,only providing the most rapid route travel time,only providing the most congested route travel time,and providing all the routes travel times.The disaggregate route-choice approach is adopted for simulation to reveal the relationship between the evolution process of network traffic flow and the strategy of providing traffic information.The simulation shows that providing traffic information to all travelers cannot improve the operational efficiency of road networks.It is noteworthy that an inappropriate information feedback strategy would lead to intense variation in various routes traffic flow.Compared with incomplete information feedback strategies,it is inefficient and superfluous to provide complete traffic information to all travelers.展开更多
窄路段作为交通场景中不可避免的瓶颈路段,其短时车流量预测对优化路径规划、改善交通状况具有重要意义。针对窄路段的时效性,同时考虑适用模型的准确度,提出一种基于佳点集初始化种群、非线性参数控制及柯西变异扰动的改进鲸鱼优化算法...窄路段作为交通场景中不可避免的瓶颈路段,其短时车流量预测对优化路径规划、改善交通状况具有重要意义。针对窄路段的时效性,同时考虑适用模型的准确度,提出一种基于佳点集初始化种群、非线性参数控制及柯西变异扰动的改进鲸鱼优化算法(IWOA)-门控循环单元(GRU)的窄路短时车流量预测模型,以SUMO(Simulation of Urban Mobility)仿真数据进行了实证研究。对比实验结果显示,IWOA具有较好的全局性、收敛速度且更加稳定。基于IWOA-GRU的窄路短时车流量预测模型,均方根误差(RMSE)指标相较于WOA-GRU、PSO-GRU、长短期记忆神经(LSTM)网络分别降低10.96%、28.71%、42.23%,平均绝对百分比误差(MAPE)指标分别降低13.92%、46.18%、52.83%,有较为显著的准确性和稳定性。展开更多
基金Key Projects in Science & Technology Pillar Program in 2007 in Beijing (No.D07020601400705)
文摘Transport system is a time-varying, huge and complex system. In order to have the traffic management department make pre-appropriate traffic management measures to adjust the traffic management control program, and release travel information to travelers, to provide optimal path options to ensure that the transport system operates efficiently and safely, we have to monitor the changing of the state of road traffic and to accurately evaluate the state of the traffic, then to predict the future state of traffic. This paper represents the construction of the road traffic flow simulation including the logical structure and the physical structure, and introduces the system functions of forecasting system in Beijing.
基金the National Social Science Foundation of China(Grant No.14XGL011)the Humanity and Social Science Youth Foundation of Ministry of Education in China(Grant No.12YJC630200)+1 种基金the Natural Science Foundation of Gansu Province in China(Grant No.145RJZA190)the Social Science Planning Project of Gansu Province in China(Grant No.13YD066).
文摘Considering both the high complexity of urban traffic flow systems and the bounded rationality of travelers,providing traffic information to all travelers is an effective method to induce each individual to make a more rational route-choice decision.Within Advanced Traveler Information System(ATIS)working environment,temporal and spatial evolution processes of traffic flow in urban road networks are closely related to strategies of providing traffic information and contents of information.In view of the day-to-day route-choice situations,this study constructs original updating models of the cognitive travel time of travelers under four conditions,including not providing any route travel time,only providing the most rapid route travel time,only providing the most congested route travel time,and providing all the routes travel times.The disaggregate route-choice approach is adopted for simulation to reveal the relationship between the evolution process of network traffic flow and the strategy of providing traffic information.The simulation shows that providing traffic information to all travelers cannot improve the operational efficiency of road networks.It is noteworthy that an inappropriate information feedback strategy would lead to intense variation in various routes traffic flow.Compared with incomplete information feedback strategies,it is inefficient and superfluous to provide complete traffic information to all travelers.
文摘窄路段作为交通场景中不可避免的瓶颈路段,其短时车流量预测对优化路径规划、改善交通状况具有重要意义。针对窄路段的时效性,同时考虑适用模型的准确度,提出一种基于佳点集初始化种群、非线性参数控制及柯西变异扰动的改进鲸鱼优化算法(IWOA)-门控循环单元(GRU)的窄路短时车流量预测模型,以SUMO(Simulation of Urban Mobility)仿真数据进行了实证研究。对比实验结果显示,IWOA具有较好的全局性、收敛速度且更加稳定。基于IWOA-GRU的窄路短时车流量预测模型,均方根误差(RMSE)指标相较于WOA-GRU、PSO-GRU、长短期记忆神经(LSTM)网络分别降低10.96%、28.71%、42.23%,平均绝对百分比误差(MAPE)指标分别降低13.92%、46.18%、52.83%,有较为显著的准确性和稳定性。