Research On The Division Of Functional Zones In Downtown Beijing Under The Background Of Geographic Big Data

With the development of social economy,the continuous improvement of the level of science and technology and the continuous advancement of the process of urbanization.The theory and practice of urban functional areas have been newly developed.The urban functional area is a high concentration of space that can realize a series of related urban functions,and effectively displays the distribution space of a specific urban functional activity.As an important space carrier that reflects the city's economic and social functions,urban functional areas collectively reflect the spatial characteristics of urban functions,and are an important manifestation of the spatial competition and development of modern urban economic activities.Under the new environment of national development,the identification and division of urban functional areas and subsequent analysis are carried out to summarize the problems in the development of urban internal space,the planning of the city,the definition of urban development models,the development of regional economy,and the optimization of urban functional areas.The construction of new urban development areas and the promotion of urbanization are of very important significance.The traditional method uses factors such as the area of ??the functional area,the geographic location characteristics of the area where the functional area is located,the wind direction and the distribution of the water system in the area where the functional area is located,and the level of housing prices in the area where the functional area is located to determine the type of the functional area.Traditional data collection involves many fields and high costs.The data update speed is slow and the timeliness is poor.The human intervention factors of the research results are relatively large,which makes the research results inaccurate.The advent of the era of big data allows us to more conveniently obtain a large number of,diversified,and highly accurate data,and to process and analyze it,so that we can more accurately and efficiently divide the city's functional areas.The source of the research data in this article is "Sunday,April 17,2019 and Wednesday,April 20,2019(weekdays and holidays)within the central urban area of??Beijing provided by China Unicom.Hourly mobile phone signaling data ",Count the communication data generated by all users within the signal range of the base station every hour from 0:00 to 24:00 within the signal range of the mobile phone communication base station in each geographic location of the operator.After the initial data is obtained,the mobile phone signaling data is preprocessed,the base station jitter is repaired,and inactive user data is eliminated.The application of mobile phone signaling data has ensured the research on data comprehensiveness,data continuity,and data accuracy.This article also uses POI data from Beijing in 2018,AOI data in Beijing in 2020,Google Earth remote sensing image data,and traditional data such as the boundary of Beijing's urban center area,and performs coordinate correction,data cleaning and preprocessing on the POI data.Wait for work.Combining the above data,the functional area of Beijing's central urban area is divided.The supervised classification method and the unsupervised classification method were used to identify and compare the functional areas in the central city of Beijing.In the aspect of supervised classification,the random forest classification algorithm is used to calculate and classify the mobile phone signaling data.In the aspect of unsupervised classification,the ISO clustering unsupervised classification method is used to analyze the mobile phone signaling data,and the supervised classification and unsupervised classification are obtained.Classification map of functional areas in the central city of Beijing.Finally,the results of the supervised classification and the unsupervised classification were analyzed and compared,and the advantages and disadvantages of the two methods were found and further compared with the remote sensing image map of Beijing.The "Master Plan(2016-2035)" etc.evaluated and analyzed the identified functional areas in Beijing's central urban area.It is found that there is still room for further development within the central urban area of Beijing,and the structural problems existing in the functional area of ??the central urban area of Beijing are summarized.