Semantic aspects of interoperable GIS

The research identifies two perspectives to interoperability; these are the data modeling perspective and the system architecture perspective.

Abstract

An increasing number of geospatial applications require information which is scattered in several independent geographic information systems.One of the main objectives of geographic information infrastructure, GH, is to provide a political, institutional, economic, and technical platform to share information.The focus of this thesis is on the technical aspects of the GH.The thesis aims at providing a mechanism to share information seamlessly among distributed, heterogeneous, geospatial information systems.Sharing information may improve decision making and reduce the cost of data collection.In general, retrieving information from distributed databases involves two steps.In the first step users search for relevant information resources in a network of information providers.In the second step users request data from the information resource.With regard to the first step, a model to search for the relevant information resources is presented.The model is called the resource discovery model, RDM.It provides a reference model to structure the metadata of the information resources in a tree of interrelated resources.In the second step, interoperability allows communication among heterogeneous, distributed, information systems.Interoperability is the ability of two or more systems to exchange geospatial information and to make mutual use of the information that has been exchanged.