Analysis On The Traffic Problems Based On The Global Positioning System Data

With the development of the science and technology, almost every taxi has installed a global positioning system. Every taxi terminal will transmits a series of data to the taxi management center, the data includes the taxi license, the time, the status(which shows the taxi is empty or full), longitude, latitude, speed and the direction information at that moment. With the taxi GPS data of Shenzhen downloaded on the webpage http://www.adamsw.com, using the software named Matlab, we first make pre-processing of these data, and then solve the following problems:1. With the taxis’ origin and destination points, combined with the map of Shenzhen, we first use the fuzzy clustering method to cluster all the OD points, and divide Shenzhen to6traffic section. Then, in order to verify the validity of the method, we select a clustering algorithm named k-means, and designs a new algorithm which can give the initial centers better, then we can divide Shenzhen to6traffic sections, which will be represented by a point at the center of it, and at the same time, all the samples included will be sent to a traffic section respectively. We can clearly see that the results of two algorithms are generally the same by contrast;2.Based on the partition of the traffic sections, we can calculate the OD-distribution matrix, which is the distribution of the origin points and destination points in each trip, and it can reflect the traffic rules. After calculating the OD space-time distribution matrix with Matlab, we can draw a3-dimensioned histogram which will show more directly;3.With the non-empty taxis’data, this paper analyzes the speed of the taxis in different period. After giving a threshold of8km/h (the taxis whose speed below8km/h were considered to be in traffic jam), we can then calculate the jam-road or intersection, the jam-time of some given road or intersection also, that will help the traffic department control the traffic better and more effectively, it can help people to select their travel route also.