The roundabouts are widely used in China,some of which have central islands as scenic spots.The crosswalks connecting to the central islands,normally full of pedestrians,have negative impact on roundabout capability a...The roundabouts are widely used in China,some of which have central islands as scenic spots.The crosswalks connecting to the central islands,normally full of pedestrians,have negative impact on roundabout capability and pedestrian safety.Therefore,this study proposes a fuzzy cellular automata(FCA)model to explore the safety and efficiency impacts of pedestrian-vehicle conflicts at a two-lane roundabout.To reason the decision-making process of individual drivers before crosswalks,membership functions in the fuzzy inference system were calibrated with field data conducted in Changsha,China.Using specific indicators of efficiency and safety performance,it was shown that circulating vehicles can move smoothly in low traffic flow,but the roundabout system is prone to the traffic congestion if traffic flow reaches to a certain level.Also,the high yielding rate of drivers has a negative impact on the traffic efficiency but can improve pedestrian safety.Furthermore,a pedestrian restriction measure was deduced for the roundabout crosswalk from the FCA model and national guideline of setting traffic lights.展开更多
Based on the effects of driving resistance on car movement,we develop a new car-following model.The simulation results show that our model can describe the kinetic property of each car during the processes of starting...Based on the effects of driving resistance on car movement,we develop a new car-following model.The simulation results show that our model can describe the kinetic property of each car during the processes of starting and braking,however the braking process will be postponed and a prominent wavefront will appear during the braking process.With the increase in driving resistance,a car's movement will become more stable during the whole process,the headway of each car will increase and the wavefront will become more prominent.In addition,our model can reproduce the evolution of a small perturbation.展开更多
基金Project(2020YFB1600400)supported by the National Key Research and Development Program of ChinaProject(2019JJ50837)supported by the Natural Science Foundation of Hunan Province,ChinaProject(71801227)supported by the National Natural Science Foundation of China。
文摘The roundabouts are widely used in China,some of which have central islands as scenic spots.The crosswalks connecting to the central islands,normally full of pedestrians,have negative impact on roundabout capability and pedestrian safety.Therefore,this study proposes a fuzzy cellular automata(FCA)model to explore the safety and efficiency impacts of pedestrian-vehicle conflicts at a two-lane roundabout.To reason the decision-making process of individual drivers before crosswalks,membership functions in the fuzzy inference system were calibrated with field data conducted in Changsha,China.Using specific indicators of efficiency and safety performance,it was shown that circulating vehicles can move smoothly in low traffic flow,but the roundabout system is prone to the traffic congestion if traffic flow reaches to a certain level.Also,the high yielding rate of drivers has a negative impact on the traffic efficiency but can improve pedestrian safety.Furthermore,a pedestrian restriction measure was deduced for the roundabout crosswalk from the FCA model and national guideline of setting traffic lights.
基金Supported by the Program for New Century Excellent Talents in University under Grant No NCET-08-0038the National Natural Science Foundation of China under Grant Nos 70971007,70701002 and 70521001the National Basic Research Program of China under Grant No 2006CB705503。
文摘Based on the effects of driving resistance on car movement,we develop a new car-following model.The simulation results show that our model can describe the kinetic property of each car during the processes of starting and braking,however the braking process will be postponed and a prominent wavefront will appear during the braking process.With the increase in driving resistance,a car's movement will become more stable during the whole process,the headway of each car will increase and the wavefront will become more prominent.In addition,our model can reproduce the evolution of a small perturbation.
