Research On The Characteristics Of Employment-residential Space In Megacities Based On Multi-source Data

At present,China is in the critical period of institutional transformation.With the rapid development of urbanization and the series of reforms of market factors such as land and housing,the urban internal space structure of Nanjing has undergone a large-scale transformation,and the occupational space relationship has long been An important part of the research on urban spatial structure,its allocation in urban space has an important impact on the production and life of urban residents,so it is widely concerned by urban geography and urban planning.In the past studies,scholars at home and abroad mainly studied the commuter and commuting issues of residents through traditional questionnaire data or population census,economic census data,etc.There are few studies at the micro scale,and based on the ratio of occupation to housing at a single scale.The calculations are often in a mainstream position for a long time,and their limitations are also obvious.With the rapid development of next-generation information technologies such as the Internet of Things,mobile Internet,and smart phones,and the open data of large-scale map websites and government websites,the formation of the current “multi-source big data environment” has been formed.The big data generated in the new environment has a large amount of data and a wide coverage,and the human activity characteristics at the microscopic scale can be depicted on multiple scales.Usually,these big data can be divided into static data,such as point of interest(POI)data,house price data,etc.;dynamic data,such as Baidu thermal data,road condition data,mobile phone signaling data,etc.,different data sources have their own advantages and disadvantages And mobile phone signaling data is undoubtedly the most research-oriented data source,its relatively accurate positioning,continuous dynamic recording,can depict personal behavior trajectories and many other advantages,thus bringing new ideas and technologies for the study of urban problems.method.At the same time,it is not negligible because of the desensitization requirement,big data usually has the problem of lack of information such as socio-economic attributes.Therefore,how to combine many emerging “big data” with “small data” such as traditional surveys,and check each other.Complementary advantages are a problem worthy of attention.Based on the above,this study attempts to combine multi-source “big data” with “small data”.Based on the principle of “difficult to stand alone and multi-source check”,the quantitative measurement system of “multiscale + double dimension” is preliminarily constructed.Taking Nanjing as an empirical research object,based on spatial database,using GIS technology,and using spatial statistics related theory,systematic multi-scale measurement analysis of occupational space relationship and residents' travel characteristics,and summarizing Nanjing employment living space.Distribution,distribution of employment and living centers,and dislocation characteristics of occupational space.Secondly,combined with the traffic survey data of Nanjing City,the sixth census data,etc.,the results of the identification of mobile phone data are checked to verify its accuracy and reliability,and multiple regression analysis is carried out on the influencing factors of residents' residential space characteristics.Explain the specific mechanism of action of the impact factor.Finally,based on the perspective of occupational and residential relations,the two-dimensional measurement results and conclusions are implemented in the overall urban planning,consistent with the structural distribution of the urban area of Nanjing,and the implementation effect of the overall planning of the last round of the city(2008-2020)Conducting an assessment,quantitatively assessing the closeness of the relationship between the main deputy city and the district,and the development degree of the main and subcity of Nanjing,provide a new perspective for the evaluation of the urban master plan,for the city's strategic planning and overall planning.Provide the basis for compilation and reference.