Research On Technology Of Web GIS Based On Web Service

GIS(Geographic Information System) can gather, store, manage, analyse and describe geographic information related to part or whole of the earth surface. In recent years, it is widely used in the fields of mineral resource management, electric power system, urban planning etc. GIS is important to the production and decision of our country. With the increase of demand to geographic information, Web GIS becomes one of the important directions in the researches of GIS. Web GIS can release geographic information data by Internet, it supports global users queries and provides GIS service. Therefore this paper chooses Web GIS as research subject. In order to solve the shortages exist in traditional Web GIS such as information sharing difficulty, bad expansibility, difficult to be integrated by other information systems, this paper begins from different spatial data model, adopt the spatial data model established by OGC and Web Service as the technical core of the system to realize a platform of geographic information service based on different operation systems. This paper consists of 6 chapters. Chapter one is the introduction, introduces the basic conceptions, characteristics, current internal and international research situation, development trends of Web GIS. The second chapter describes current structure of Web GIS and Web GIS development technology, and does detailed comparison to various kinds of ways and characteristics of realizing technology. Chapter three studies the principles, related concepts, system model, architecture and working process of the Web GIS based on of Web Service, describes key technology used to establish the system, summarizes the characteristics of Web GIS Service and improvement compared with traditional Web GIS. Chapter four studies the model, framework, and expression to geographic information of the GML(Geography Markup Language) developed by OGC, considering the defect of the raster graphic in Web GIS, introduces a kind of vector graphics SVG to solve the transmission and mutual problem. Chapter five discusses preliminary practice of the Web map serving prototype system based on Web Service, including storage and design of the database based on GML, design of the map service interfaces based on Web Service, design of the relevant functions of client browser based on SVG. In the last chapter, general review and some improved suggestions are given for the dissertation.