| With the development of the computer technology, network communication technology and the earth space technology, WebGIS is becoming a popular information tool, more and more Web websites offer space data services. But we have to face such a reality: It is unable to well communicate and cooperate between tens thousands of Web websites, and it is very difficult to visit, deal with distribute magnanimity space datum in Web through browser. Because the reasons of enterprise policy and data safety, the space resource mostly exist in specific GIS systems or tabletop applications, doing things in their own way and close relatively, thus the detached space information islands are formed. It is difficult to meet the need of the sharing of space information on Internet. Traditional three-ply WebGIS model and subsequent distributed WebGIS model based on the middle part, No matter they adapt RMI, DCOM or adapt distributed object technology, such as CORBA etc, though there is better progress in realize the balance of the network load, distributed calculation, etc, but it is still powerless to solve the operation each other and data integration etc between isomerous systems on the platform of open geographical information service.XML (extensible Markup Language) has obvious advantage in complicated digital coding and exchanging with information; it is an effective way to solve the subject matter that WebGIS faces. Web Service is another brand-new technology to set up distributed systems in the internet environment. WebGIS based on XML Web Service has characteristics of distributed, capable of operation each other, being convenient to integrate. It is a trend of WebGIS.The thesis focuses on exploring the new network technology of XML and Web Service, and studying the application in the field of GIS based on the both, then proposes constructing a WebGIS platform with XML Web Service system. The research of this thesis finishes the main work as follow:I. The thesis has introduced the current development situation of WebGIS , the concept and characteristic of WebGIS and Open GIS Consortium (OGC) firstly. Then it analyzes comparatively the main development technology, tactics of realizing and their advantages and disadvantages in nowadays WebGIS. Have pointed out that nowadaysthe subject matter that WebGIS exists is: the systems developed by different G1S software products can not fully share in geographical data, and the similar functions can't operate each other.II. The thesis has analyzed XML application situation in the field of WebGIS at present, has studied "Simple Feature Model" and GML that OGC issues, and has described the characteristic and relevant technology of GML in detail. Then it is concluded that adopting XML and GML as the carrier of geographical data storage and transfers can be convenient to realize the integration and share of many isomerous geography datum.III. The thesis has relative deeply discussed the three key technologies of Web Service: these are SOAP (Simple Object Access Protocol), WSDL (Web Service Description Language) and UDDI (Universal Description, Discovery and Integration). Using Web Service to set up a WebGIS environment of loose coupling can bring a brand-new design idea for the GIS application.IV. On the basis of consulting the open geographical network service models of OGC, the thesis has put forward an design of open WebGIS scheme of based on XML Web Service system, and provided design of every main service interface. Finally, the author developed a set of simple prototype systems according to the scheme; then it has verified the exactness and feasibility of the scheme.The study of WebGIS based on XML Web Service is a brand-new research field. The space data modeling technology and data transform technology based on GML, and the system framework technology based on Web Service bring a great impact on traditional WebGIS.At present, the domestic and international study on this respect has been already rip basically in theory. Whereas in practice, because of t...
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