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Application of Spatio-temporal Big Data in Smart City : —taking Kaifeng idle land administration as an example

Under the background that smart city construction has become a national strategy, the traditional urban spatial development model based on the analysis of historical data such as urban population, economy, resources and environment is facing the innovation of data source and research framework. As an important branch of the big data, spatio-temporal big data provides strong data support for the development of smart cities with its massive and rapid characteristics. In recent years, the development of land market has sometimes deviated from the original intention and orbit of resource allocation, leading to the increasingly prominent contradiction between the urban demand for construction land and land resource allocation and generating a lot of idle lands. Taking Kaifeng City as an example, this paper analyzed the main causes of idle land through multi-source spatiotemporal data such as remote sensing monitoring, network collection, interview survey and field survey, combed the practices and effects of revitalizing idle land in Kaifeng City, and put forward governance opinions based on the perspective of spatiotemporal big data. The results showed that: (1) The disposal area of idle land presented an increasing trend from 2014 to 2020 in Kaifeng City, however, there were great differences between different counties. (2) The main reasons for idle land in Kaifeng are urban strategic shift; the protection of ancient city; deficient early-stage preparation; "Inversion" problem. (3) Suggestions on idle land management based on big data: Build an urban digital information management and integration platform to realize indepth and systematic investigation of existing idle land; Promote the process of networked information sharing management and realize multi department collaborative planning and processing; Establish a smart city management platform for on-demand services, and strengthen the assessment and supervision of government departments. In order to provide a solution based on spatio-temporal big data for the problem of idle land in Kaifeng and other cities in the process of smart city construction.