Research On Multi-view Exploratory Visual Analysis Technology Based On Digital Earth Platform

Since 1998,U.S.Vice President Al Gore proposed the idea of a "Digital Earth" that could integrate,organize,process and visualize geospatial data sets on a threedimensional Earth model.Numerous digital earth platforms have been widely used in geological research and have greatly facilitated the diversification of information presentation.However,most of the current digital earth platforms adopt a single-view model.In today's information explosion,a single-view digital earth platform will not be able to meet the demand for rapid discovery and understanding of similarities and differences among massive geospatial data sets.The emergence of a multi-view virtual sphere platform based on the concept of Coordinated Multiple Views(CMV)provides a new way of thinking to solve these problems.However,there are still some problems with coordinated multi-view digital earth systems,such as limited data sources for users to choose from,a single form of data comparison,and lack of cross-platform large-scale remote sensing data analysis functions.Therefore,this paper will couple the remote sensing big data cloud platform GEE with the digital earth platform Cesium,and research the visualization method of efficient browsing,comparison,and analysis of multiple geospatial information based on ensuring the coordinated linkage of each view.The main research contents are as follows:1.Extend multi-view platform data sources and provide massive data integration solutions.This paper combines HTML5 file loading technology,OGC(Open GIS Consortium,Inc)standard,and GEE to provide local and online data integration routes and petabyte-level remote sensing catalogs for the multi-view platform.And it provides a comprehensive management approach of dynamic and static multi-source data for multi-view platforms.The solution reduces system data storage costs and improves data comparison efficiency.2.This paper draws on and integrates the principles of complex object comparison to construct a generic system of comparison and classification for multi-view digital earth systems This paper studies the multi-view comparison method based on the Cesium platform.Explore the form and implementation of juxtaposition,superposition,and explicit coding in the Cesium platform,focusing on implementing a form of codematching by GEE.This paper designs a data comparison classification system for the multi-view digital earth platform by integrating three comparison methods.This classification system effectively develops the data comparison paradigm of the multiview digital earth platform.3.In this paper,we firstly study the implementation principles of three basic spatial analysis modules,such as terrain analysis(elevation analysis,slope direction analysis,profile analysis),spatial calculation analysis,and through-view analysis(viewpoint analysis,field of view analysis,video RF);and then effectively integrate these spatial analysis functional modules into the multi-view platform.In addition,it provides an online remote sensing analysis function for the system in combination with the GEE4.This paper builds a multi-view exploratory visual analysis system and validates the system's effectiveness in the context of the East African locust plague case in early2020.The results show that the system developed can observe the spatial and temporal patterns of geographic data in a fast,synchronized,coordinated,and convenient way in the case of a locust disaster in East Africa.The research and application of this paper further demonstrate that the multi-view exploratory analysis system has good application value and can assist people to better explore the inherent patterns among data.