Study On The Calculation Of Urban Accessibility Based On Taxi Trajectory

With the rapid development of urbanization,the scale of urban space and the number of population expand continuously.It is becoming more and more important to understand the layout of urban space,to dig out the law of the residents and to study the accessibility of the city.Accessibility is of great significance for consolidating urban traffic planning,monitoring traffic project implementation effect,and interpreting urban spatial structure.With the popularization of GPS technology in the management of taxi operation,the taxi trajectory data is gradually becoming the important data of optimizing urban traffic and the important input data for analysis of resident trip analysis.After a thorough study of the accessibility research paradigm and the application of taxi trajectory data,this paper explains and compares the basic model of accessibility calculation and the conventional data source,summarizes the range and its advantages and disadvantages of each model,and considers that the accessibility calculation model based on the actual operation information of taxi travel has ruled out the researchers.The subjective cognition of land use and traffic system holds the actual running status of each traveler on its own characteristics and traffic flow,which is more pertinent and more efficient.In the model selection,first of all,from the perspective of traveler psychology,it is considered that the main purpose of traveler is to obtain the opportunity distribution which can be provided by the destination.At the same time,the distance and time consumption of travel are considered,and the accessibility is modeled and analyzed from the two angles of opportunity demand and traffic impedance.With the development of GIS technology,a comprehensive and accurate city POI data update speed is timely and easy to obtain.This paper establishes an opportunity model with the number and richness of the destination POI as the main parameter,and builds the connection impedance model with the actual travel time and the non-straight line coefficient of the taxi passengers as the main parameters,and through the normalization of the two parties.After processing,the accessibility is defined and modeled.In order to extract the required information from the mass taxi trajectory data,after completing the data preprocessing,this paper proposes an improvement of the Douglas-Peucker trajectory compression algorithm considering traveling-speed,and then proposes a STING grid clustering algorithm to divide the research space,uses the Matlab to deal with the mass trajectory and the extraction of the passenger information,and uses the ArcGIS to visualize the taxi travel distribution.Finally,choosing the outer ring of Shanghai as the research object,and establish the research period based on the spatial and temporal analysis of taxi operation in Shanghai,so as to achieve accessibility case calculation.A comparison between functional land use travel analysis and infrastructure traffic service level based on accessibility is put forward.The study of this paper makes it possible to calculate the spatial accessibility and GPS data.It provides a theoretical basis for the optimization of urban spatial structure and the optimization of public transportation,which is of great significance in the era of large data.