Research On Data Registration Mechanism For Spatial Information Cloud In G/S Model

In recent years, with the steady progress of the construction of informationtechnology, spatial information applications has gradually deep into people’s dailyproduction and life, while people are benefiting from advances in informationtechnology, they put forward higher requirements for spatial information services, butthe traditional information access mode in response to massive spatial informationprocessing and sharing appeared to be inadequate at the same time. For this situation,the G/S mode using " request-Services-aggregate " model ofworking mechanism[1],makes application services aggregated on the client side and information data gatheredon the server side, in such a way to solve a series of problems faced by the spatialinformation exploited in the process of data management, maintenance, transmissionand data processing. Based on this architecture, it build a spatial informationapplication platform which mainly consists of Geo-Browser and spatial informationservice cloud to meet the popular demand for spatial information applications.In G/S mode, the spatial information service cloud is responsible for themanagement and maintenance of spatial information, and provide a highly reliabledata-sharing service for the G side. Due to the complexity and diversity of spatialinformation, spatial information service cloud in the process of data storage,transmission and processing facing a severe test. How to establish a perfectinformation gathering and discovering mechanism for massive, heterogeneous, and aplurality of spatial data is the major problems spatial information service cloud faced.Therefore, only through the establishment of data registration center to realize theunified organization and exchange of heterogeneous data.Data registration center through the unified management and maintenance of spatial information metadata, to achieve the purpose of spatial informationmanagement and sharing. There are a large number of metadata standards in thespatial information service cloud, and much of them lack uniform standards and norms.How to realize efficient data registration mechanism for S-side users and informationdiscovering for G-side users is the main task Data registration center faced, it is alsothe focus of this thesis studies. In the course of the study of the data registrymechanism in the spatial information service cloud, this thesis has achieved thefollowing results:(1) Designed of a unified metadata standards in the spatial information servicecloud.In view of the diversity of metadata standards in the spatial information servicecloud, combined with data registration center uses metadata to provide data resourcesregistry and publishing for users, design a unified metadata standards, to resolve aseries of problems in the course of data registry with different types of metadata,simplified the metadata registry process, improved work efficiency of the dataregistration center, laid the foundation for the integration and sharing of spatialinformation resources.(2) Designed and developed a prototype system for data registration center.Using a combination of the OpenLDAP directory server and relational database,constructed the storage environment for data registration center, established thesystem work processes and functional modules contained in the data registrationcenter.Formulated the main functions of data registration center prototype system.Provided G-side users and S-side users with access interface respectively: used theStruts framework to develop a metadata registry and management Web service systemfor S-side users, which provided metadata registry, update, view, deletion and otherfunctions; for G-side users, provided the access interface who can access to the dataregistration center via HTTP protocol, and defined the HGML data exchange formatfor both communication parties.In obtaining above-mentioned research results at the same time, the innovation ofthis thesis is mainly reflected in the following two aspects:(1) Proposed a method of constructing data registration center based on metadatastandards framework.In the spatial information service cloud, through the establishment of the coremetadata standard system, eliminating the differences ofthe different types of metadata in the expression of public information and the extraction process, easy to implement aunified metadata organization and management, created premise condition for theconstruction of data registration center.(2) Presented a data registration center architecture model.Made metadata standards as the basis of the data resources registry in the spatialinformation service cloud, established the specific metadata registry and publishingprocesses, and then designed the architecture model, which optimized from the datastorage efficiency, query efficiency and system scalability.