甘肃科学学报

交叉口是城市道路交通流汇聚点和污染物排放热点，为构建交叉口生态配时方案，降低车辆尾气排放，首先基于便携式排放测试系统(PEMS)在模拟交叉口路段开展排放测试，并结合仿真方法对车辆匀速、加速、减速和怠速等工况的排放因子进行标定；然后以车辆延误、排队长度和尾气排放量最小化为目标，通过遗传算法(GA)对交叉口交通流参数进行求解；最后构建实际交叉口和仿真交叉口配时方案多目标生态型优化模型，并对模型进行验证。结果表明：(1)基于PEMS和模拟交叉口相结合的车辆排放因子方法，在时间和空间维度上刻画车辆不同工况排放特性方面具有一定可行性；(2)通过多目标优化模型优化实际交叉口配时方案后，交叉口车辆延误、排队长度和污染物排放总量在一个信号周期内与优化前配时方案相比最大减少率分别达17.86%、17.40%和13.65%;(3)多目标优化方法优化仿真交叉口配时方案后，交叉口车辆延误、排队长度和污染物排放总量与优化前配时方案相比显著减少，分别降低15.70%、10.50%、9.11%。研究表明：考虑排放的多目标优化信控交叉口配时方案在最大化交叉口通行效率和减少污染物排放方面具有较好的可信度和鲁棒性，该方法可为城市道路交通管理控制中统筹通行效率与污染物排放、构建生态型交叉口提供借鉴。

The intersection is the gathering point of urban road traffic flow and the hotspot of pollutant emission.Aiming for the construction of the intersection ecological timing scheme and vehicle exhuast emission reduction.Firstly, based on the portable emission measurement system, the emission test and simulation method of the simulated intersection section are conducted to calibrate the emission factors of the vehicle at the intersection, such as uniform speed, acceleration, deceleration and idle speed.Then, to minimize vehicle delay, queue length, and exhaust emission, the traffic flow parameters of the intersection are solved by a genetic algorithm.Finally, the multi-objective ecological optimization model of the timing scheme of the actual intersection and the simulated intersection is constructed and verified.The results show that:(1) The method of extracting vehicle emission factors based on PEMS and simulated intersections is feasible in describing the emission characteristics of vehicles under different working conditions in time and space dimensions.(2) After optimizing the actual intersection timing scheme through the multi-objective optimization model, the maximum reduction rates of vehicle delay, queue length, and total pollutant emissions at the intersection in a signal cycle are 17.86%,17.40% and 13.65%,respectively, compared with the pre-optimization timing scheme.(3) After the multi-objective optimization method optimizes the simulation intersection timing scheme, the vehicle delay, queue length, and total pollutant emissions at the intersection are significantly reduced compared with the pre-optimization timing scheme, reaching 15.70%,10.50% and 9.11%,respectively.It is revealed that the multi-objective optimization signalized intersection timing scheme considering emissions has good credibility and robustness in maximizing intersection traffic efficiency and reducing pollutant emissions.The method proposed in this paper provides a reference for coordinating traffic efficiency and pollution emissions and building ecological intersections in urban road traffic management and control.