Lookup NU author(s): Aled Greenhalgh,
Dr David Fairbairn
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
The UK government and geomatics industry has developed “an industry standard for integrating and sharing business and geographic information from multiple sources” (DNF Expert Group, 2005), the Digital National Framework (DNF). The Framework aims to enable easy and reliable integration of business and geographic information shared with the confidence that they are referring to the same location and entity in the real world. The DNF is an initiative managed by the UK national mapping agency, the Ordnance Survey (OS) as well as other geodata providers such as the UK Hydrographic Office (UKHO) and Land Registry alongside commercial organisations across the property, utilities, environment and transport sectors, for whom this aim is a crucial requirement. These stakeholders are represented in the DNF Expert Group, the Framework’s notional owner. The Framework is built around the use of a unique identifier consistently referencing each spatial feature throughout its lifecycle, and the use of this identifier to link application objects to objects in a national reference base. The aim of this work is to develop a use case for semantic interoperability in geographic information (GI) through expressing semantics within the DNF, and to subsequently provide a specific solution around this scenario. Semantic interoperability is already considered vitally important within GI (Harvey et al., 1999): this work will go some way to establishing the value of semantics within the Framework and will provide a possible approach to encoding them. The overall approach to semantics is one broadly taken from the Semantic Web research community (Herman, 2008, Berners-Lee et al., 2001). As such, in addition to those standards which are specified within the Framework the standards and services defined by the World Wide Web Consortium (W3C) and the Open Geospatial Consortium (OGC) will form the core technologies as well as more specific standards which are recognised within particular communities under study. The methodology in use is to firstly identify use cases in these areas where there exists a need for interoperability of geographic information and where the current capabilities of the DNF are insufficient to fully meet interoperability requirements. In each case a set of competency criteria is derived which identifies the minimum functionality to provide a solution to these requirements. A model of objects and their properties and relationships for this specific domain is then built: this is an ontology in the sense of ‘a specification of a conceptualisation’ (Gruber, 1993). Here an ontology provides a formal specification of an abstract, simplified view of the world that we wish to represent and which a system can commit to. This model is then used as a central component in building a system which delivers the level of semantic interoperability as specified in the competency criteria. Ontologies in this sense are being increasingly studied and used as tools within GIScience (Agarwal, 2005). The approach employed here is to use ontologies and description logic (DL) alongside the existing licensing spatial databases in order to equip the Framework with a means of representing more complex geographies The combination of ontology and DL has been successfully used to ensure consistency in databases (Frank, 2001), and to provide semantic integration of multiple representations in spatial databases (Stoter et al., 2006).
Author(s): Greenhalgh ATH, James PM, Fairbairn D
Publication type: Conference Proceedings (inc. Abstract)
Conference Name: WORLDCOMP'08: The 2008 World Congress in Computer Science, Computer Engineering, and Applied Computing
Year of Conference: 2008