Research And Practice Of Thematic Map Service Based On Spatio-temporal Big Data Platform

At present,smart city construction has become an important trend in the development of global city.Smart City plans to break down the data barriers existing among various departments to achieve data sharing and interoperability.Thematic map is an indispensable tool in the construction of smart city.thematic map is the most intuitive,effective,easy to understand and generalized method among all the ways to express spatial information.The spatiotemporal big data platform is the brain of a smart city,integrating various data in urban space.Data from different departments and fields does not need to be directly provided,but can be shared by providing corresponding interfaces to achieve data service,in order to achieve urban planning,regulation,and operation.The spatiotemporal big data platform achieves cross regional service composition of service chains through workflow patterns,and service granularity is the foundation for implementing workflow patterns.The spatio-temporal big data platform divides the service granularity very carefully,mainly to meet different business needs and application scenarios,improve the reusability and flexibility of services,and achieve efficient collaboration of services and deep data integration.In this context,the production of thematic map based on spatio-temporal big data should be transformed to data service,and thematic map services need to be divided into smaller granularity.To achieve this goal,the work done in this article is as follows:(1)The service design of thematic map based on spatio-temporal big data platform is proposed.This article decomposes the thematic mapping process into indivisible atomic services,including data services,thematic data classification processing services,thematic symbol services,map template services,map decoration services,etc.These atomic services are combined through service composition and service chain to form a semi-automatic thematic mapping mode.(2)Created a thematic data classification model service method.The paper designs four classification service methods: equidistant classification model service,logarithmic classification model service,square root classification model service,and natural breakpoint method classification model service.(3)Designed a thematic symbol service method.Designed and implemented thematic feature services based on points,lines,and surfaces,and encapsulated six major categories of thematic statistical symbol services.(4)Created a map template service.Template service refers to the whole process of calling thematic map service.The template services designed in this article specifically include statistical thematic template services and element thematic template services.(5)The thematic map service system based on spatio-temporal big data platform is realized.The thematic map service system is tested and applied.