The Earthquake In Sichuan Province The Design And Implementation Of Spatial Information Service System

In a variety of natural disasters, earthquake disaster is one of the most serious disasters causing casualties and economic loss. After the earthquake happens,there are serious problems for the rapid assessment and effective relief measures of seismic disaster. With the progress of science and technology, many new technologies, such as Geographic Information System (GIS), are widely used in the field of earthquake disaster reduction. In recent decades, with the rapid developments of Computer Network, WebGIS technology,namely applying Network technology into GIS field,which is introduced in the field of earthquake prevention and disaster reduction, becomes the one of the trends of GIS development.The emergence of WebGIS technology overcomes many problems for small scope and spatial data sharing difficulty of traditional GIS technology.So further study of WebGIS technology will play an important role for earthquake damage evaluation and feasible rescue plans.This paper illustrates system analysis and design based on the actual user demand of earthquake system.The earthquake space information service system in Sichuan province based on B/S mode was designed and implemented by the way of the combination of ArcGIS Server technology and ArcSDE technology.The primary research work in this paper is as following:1) This paper made a further research for the whole framework of the system and put forward the technology route of the system development. Each function module was designed in the system, including the query function of earthquake space information, seismic damage assessment, rescue implementation, outputting thematic map, editing information online, Web map service and many other functions.2) Based on geographic characteristics and the historical experience data in Sichuan province, the models corresponding with Sichuan regions were gathered, including building damage analysis, casualties, economic loss assessment and decision-making models. The quickness and accuracy of earthquake damage assessment were improved through programming and optimizing the models. 3) On the basis of the actual demand of the earthquake system, ArcSDE technology and Geodatabase model were applied to the system to store and organize spatial data. The combination and storage of spatial data and attribute data are realized by ArcSDE and SQL Server database, making for the data management and maintenance. So the establishment of spatial database and attribute database provides the stable data services for the upper application.4) The paper chose ArcGIS Server as development platform and illustrated the asynchronous refresh principle of Ajax technology. ArcGIS Server Web ADF development framework implements a good combination of Ajax and WebGIS.The system used Ajax technology to control the partial page refresh, increasing the user’s experience and the system’s work efficiency.