中文摘要：

对外交通枢纽对城市内部的客流交通有重大影响,研究其乘客在市内的OD分布对优化设计地面接驳线路、沿线站点等有重要意义。本文基于北京出租车GPS数据,选取具有代表性的3类对外交通枢纽（机场、火车站、汽车客运站）,采用标准差椭圆分析、核密度估计以及分时点统计等方法,研究了北京对外交通枢纽乘客OD时空分布特征。结果表明：（1）机场、火车站客流量远大于汽车客运站,其中首都国际机场与北京西站的对外出行客流量最大,南苑机场和北京北站的对外出行客流量较少;（2）机场乘客主要分布在四环以里大部分地区以及五环以里部分地区,时间上主要分布在除凌晨1-4时的各个时间段;火车站乘客主要分布在四环以里区域,时间上主要分布在6-21时;汽车客运站乘客主要分布在各客运站周边区域,时间上主要集中在6-17时;（3）北京南站与北京西站、北京站间的客流联系较多,可考虑开通北京南站与二者间的地面接驳专线。此外,抵离首都国际机场、南苑机场的乘客主要分布区域与新开通的机场往返市区的巴士线路站点较为一致,说明采用出租车数据进行乘客OD分析可为决策部门进行相关交通规划提供依据。

英文摘要：

External traffic hub has a major impact on inner-city traffic, hence it is of great significance to study its passengers＇ OD distribution within the city for designing ground connection lines and stops along the route. Based on the Taxi GPS data in Beijing,this paper selected three typical types of external traffic hubs（airport, train station, bus passenger station） and studied the passengers＇ OD temporal- spatial distribution characteristics of external traffic hubs in Beijing by using methods of standard deviational ellipse, kernel density estimation and statistical analysis. The results showed that：（1） passenger traffic in the airport and the train station is much larger than the bus passenger station. Beijing Capital International Airport and Beijing West Railway Station have the largest outbound passenger capacity, while Beijing Nanyuan Airport and Beijing North Railway Station have fewer outbound passengers.（2） airport passengers are mainly distributed within most parts of the 4th Ring Road region and some parts of the 5th Ring Road region. The passenger traffic in the airport covers all the time periods except a period between 1 am and 4 am.Passengers of the train station are mainly distributed within most parts of the 4th Ring Road region and their traffic time mainly occures between 6 am and 9 pm. Passengers of each bus passenger station are mainly distributed in the peripheral area of itself and their traffic time mainly occures between 6 am and 5 pm.（3） Beijing South Railway Station has a strong connection with Beijing West Railway station and Beijing Railway station, so it is worth opening special connection lines between Beijing South Railway Station and the other two stations. In addition, the distribution areas for passengers of Beijing Capital International Airport and Beijing Nanyuan Airport are in accordance with certain new airport bus lines opened recently, which demonstrated that passengers＇ OD analysis based on taxi GPS data may indeed provide a good basis for the dec