ABSTRACT

Rapid economic growth in recent decades has led to a rising motorization and congestion in urban areas. Congestion at intersections is considered as the prime source of emissions. This study presents a CO emission-based adaptive signal control for isolated intersections. Traffic dynamics at signalized intersections are modeled on the time-space diagrams using the shockwave theory and information from loop detectors installed upstream of intersections. Emissions are estimated from the sum of the product of emission rates and times spent by vehicles in each operating mode. With the assumption that traffic demand remains the same in the next cycle, a split adjustment policy is established by incrementally adjusting splits so that the total intersection emissions gradually reduce. Cycle length is adjusted in the next cycle by evaluating the residual queues. Efficiency of the proposed control algorithm is investigated via simulation. It is found that when the sum of flow ratios of the critical movements is between 0.6 and 1.0, the proposed adaptive control produces smaller CO emissions, delay, and stop than the Webster fixed-time control does with the 0.025 level of significance. On average, the proposed control algorithm can reduce CO emissions by 7.67 percent when compared to the Webster fixed-time signal settings. However, the reduction depends on the sum of flow ratios.

摘要

近几十年来，经济的快速增长导致城市地区的机动化和交通拥堵状况加剧。交叉口的拥堵被认为是主要的排放源。这项研究提出了基于CO排放的自适应信号控制的孤立路口。信号波交叉路口的交通动态使用冲击波理论和来自交叉路口上游安装的环路探测器的信息在时空图上建模。排放是根据排放率与每种操作模式下车辆所花费时间的乘积之和估算的。在下一个周期内交通需求保持不变的假设下，通过逐步调整路段来建立路段调整策略，以使交叉路口总排放量逐渐减少。通过评估剩余队列，可以在下一个循环中调整循环长度。通过仿真研究了所提出控制算法的效率。结果发现，当临界运动的流量比之和在0.6到1.0之间时，所提出的自适应控制所产生的CO排放，延迟和停止比Webster固定时间控制在0.025的显着性水平上要小。与Webster固定时间信号设置相比，建议的控制算法平均可减少7.67％的CO排放。但是，减少取决于流量比的总和。并比Webster固定时间控件的0.025显着性水平停止。与Webster固定时间信号设置相比，建议的控制算法平均可减少7.67％的CO排放。但是，减少量取决于流量比的总和。并比Webster固定时间控件的0.025显着性水平停止。与Webster固定时间信号设置相比，建议的控制算法平均可减少7.67％的CO排放。但是，减少量取决于流量比的总和。