Research On The Technology Of Geographic Information Services Aggregation

As the geographic information is increasingly applied, the way and the frequencyof people use geographic information services are dramatically increasing. In thetraditional ways, departments of surveying and mapping provide basic geographicaldata in an offline fashion, which cannot meet advanced requirements of rapidacquisition or integration applications of geographic information. Departments ofsurveying and mapping have started constructing the public service platform ofgeographic information at a variety of levels, such as country, province, and local. Therelated professional departments have also been building various information resourceservice platforms. Regarding the geographic information applications, the horizontalaspect includes services for professional transportation services, water conservancyservices and land services. Similarly the vertical aspect includes geographical servicesfor the whole country, the province or the local. The data structures are different amongdifferent sectors. In this context, it is very essential and meaningful to make research onaggregation service between heterogeneous platforms and the implementations ofintegrated dispatching and aggregation for heterogeneous services.Due to the multi-source and heterogeneous characteristics of geographicalinformation, this research focuses on aggregation technology of different geographicalinformation service based on ‘MAP WORLD’. Three research aspects are description ofbundle of services and meta-services, architecture design of service aggregationsoftware, and realization of the service aggregation system. The main work andinnovation for this study are as follows:(1) Standards of Service Description. The heterogeneous geographic informationservices were analyzed initially. The basic requirements of such services were described.A service group consisted of7-tuple (ID, Name, Description, Operation, Input, Output,Capability), and meta-service is a8-tuple (ID, Name, SGID, Description, Url, Token,Range, Qos). The publishment of services and registration module databases supportingthe registration, discover and calls for the services is designed. (2) Architecture Design of Aggregation software. This article designed thearchitecture of aggregation software based on "MAP WORLD" was developed byintroducing the idea of service group. Also, the paper designed the service registry anddirectory release, service dispatching and aggregation, aggregation service release andmanagement function module.(3) System Development of Aggregation software. In the system, some functionssuch as tiled map service aggregation, path analysis service aggregation, and place namesearch service aggregation are developed. The passing rate of function tests could reach74.63%.With regard to the performance, the response of the action is less than18seconds, and safety test had been completely passed. The results showed that thedevelopment of this system could effectively meet users’ needs and designrequirements.