一种公交等时线的计算方法及其应用

摘要

Bus isochrones indicate the maximum scale of bus system can extend during one time interval.A calculation method of isochrones is proposed in this paper and it can be applied to the analysis of public transport accessibility.The travel process by bus is analyzed and divided into five parts:walking to the bus stop from departure,waiting for buses,boarding buses,transfer and walking to the destination.Specific calculation methods of time cost are proposed for each part,respectively.Then,the isochrones are obtained by the grid method and the inverse distance weighting method.The bus GPS data of Guangzhou,China is used to draw the isochrones maps and to demonstrate the Tee mall.Furthermore,the space-time accessibility is measured in the covering area of a unit time isochrones and the accessibility differences of different directions are then analyzed through profiles.%公交等时线刻画了在相同时间内利用公交可达的最大范围.提出一种公交等时线的计算方法,并将其应用在城市时空可达性的计算中.首先分析了公交出行时空过程,认为公交出行时空过程中应该包括步行到车站、候车、乘车、换乘、从车站到达目的地等子过程,然后针对每个子过程提出其耗费时间的计算方法.根据给定出发地点和总出行时间,采用网格法和反距离加权插值法得到等时线.利用广州市公交GPS数据,绘制得到以广州市天河城为中心的等时线.最后以单位时间等时线所覆盖空间范围作为可达性的度量值,计算公交出行方式下广州市天河区的时空可达性,由可达性剖面图分析其不同方向的可达性差异.