中文摘要：

利用车载尾气检测设备和GPS系统收集了北京市重型柴油公交车实际行驶和排放数据,引入汽车比功率（VSP）参数,建立柴油公交车排放预测方法,并对柴油公交车的实际运行和排放特征进行了分析。行驶特征分析表明,公交车在北京市五环内的平均速度为17.17km/h,其80%以上行驶处于VSP区间[-1,3]kW/t;排放特征分析表明,柴油公交车瞬时高排放集中在VSP≥10kW/t区间,表明高加速或快速行驶是引起瞬时高排放的主要原因。

英文摘要：

Real-road driving and emission data of heavy-duty diesel transit buses in Beijing are collected by using portable emission measurement system（PEMS） and global positioning system（GPS）.By introducing vehicle specific power（VSP） parameter,an emission prediction method for diesel buses is developed and the driving and emission features of diesel buses are analyzed.The driving feature analyses show that the average speed of transit buses running on the routes inside 5th ring road is 17.17 km/h,and 80% of driving is within the VSP bin of kW/t,while the emission feature analyses indicate that instantaneous high emission rates occur at the bins with VSP≥10kW/t,meaning that driving with high speed or acceleration is the major cause of high emissions.