Ordnance Survey, the national mapping agency of Great Britain, is investigating how semantic web technologies assist its role as a geographical information provider. A major part of this work involves the development of prototype products and datasets in RDF. This article discusses the production of an example dataset for the administrative geography of Great Britain, demonstrating the advantages of explicitly encoding topological relations between geographic entities over traditional spatial queries. We also outline how these data can be linked to other datasets on the web of linked data and some of the challenges that this raises.is already evidence of how important GI is for the Web today, from the large investment of all three main search engine providers, Google, Microsoft and Yahoo!, in collecting GI to aid local search. A place name is one of the simplest forms of location information. Place names are often used in simple web searches such as: "Find me all pizza restaurants in Southampton", or "Find me holiday destinations in Cornwall". This suggests that gazetteers (indexes of place names) are a very useful addition to the semantic web. Geonames (http://sws.geonames.org/6269131/about.rdf), DBpedia (http://DBpedia.org/ page/England) and the CIA World Factbook (http://www4.wiwiss.fu-berlin.de/factbook/) are RDF datasets that include this type of information. However, none of these properly describes the official administrative geography of Great Britain as laid down by Parliamentary legislation though Statutory Instruments (House of Commons 2008), a resource that has already been requested by other RDF projects (Tennison and Sheridan 2008). With respect to geographical information, RDF does have a significant limitation in that it cannot support any form of spatial indexing. Thus the ability to spatially query GI in the traditional sense, or to perform many standard GIS operations such as buffering or containment within a user defined area, are either not possible, or would prove to be so computationally inefficient as to render them unusable. At this stage we see this as an important constraint on what is possible, but not as a reason to abandon RDF. Rather, we feel there are still significant advantages to using RDF for GI and, in time, we expect solutions to these limitations to emerge. Given our desire to investigate the representation of GI using RDF, the need for authoritative geographical names, and the limitations imposed by RDF in terms of spatial querying, we decided that a gazetteer representing the administrative areas of Britain would be the most appropriate form of geographical resource to investigate.The original description of the Semantic Web as outlined in Berners-Lee et al. (2001) was a vision of how software agents could understand the meaning of web content in order to find and process information across the web more accurately. The emergence of the Linked Open Data movement (Bizer et al. 2008b) or "web of data" from the original web of documents moves us further along the path towards ...

The Geosciences and Geography are not just yet another application area for semantic technologies. The vast heterogeneity of the involved disciplines ranging from the natural sciences to the social sciences introduces new challenges in terms of interoperability. Moreover, the inherent spatial and temporal information components also require distinct semantic approaches. For these reasons, geospatial semantics, geo-ontologies, and semantic interoperability have been active research areas over the last 20 years. The geospatial semantics community has been among the early adopters of the Semantic Web, contributing methods, ontologies, use cases, and datasets. Today, geographic information is a crucial part of many central hubs on the Linked Data Web. In this editorial, we outline the research field of geospatial semantics, highlight major research directions and trends, and glance at future challenges. We hope that this text will be valuable for geoscientists interested in semantics research as well as knowledge engineers interested in spatiotemporal data.

The perspective of European National Mapping Agencies (NMA) on the role of citizen sensing in map production was explored. The NMAs varied greatly in their engagement with the community generating volunteered geographic information (VGI) and in their future plans. From an assessment of NMA standard practices, it was evident that much VGI was acquired with a positional accuracy that, while less than that typically acquired by NMAs, actually exceeded the requirements of the nominal data capture scale used by most NMAs. Opportunities for VGI use in map revision and updating were evident, especially for agencies that use a continuous rather than cyclical updating policy. Some NMAs had also developed systems to engage with citizen sensors and examples are discussed. Only rarely was VGI used to collect data on features beyond the standard set used by the NMAs. The potential role of citizen sensing and so its current scale of use by NMAs is limited by a series of concerns, notably relating to issues of data quality, the nature and motivation of the contributors, legal issues, the sustainability of data source, and employment fears of NMA staff. Possible priorities for future research and development are identified to help ensure that the potential of VGI in mapping is realized.

Abstract:The mathematical nature of description logics has meant that domain experts find them hard to understand. This forms a significant impediment to the creation and adoption of ontologies. This paper describes Rabbit, a Controlled Natural Language that can be translated into OWL with the aim of achieving both comprehension by domain experts and computational preciseness. We see Rabbit as complementary to OWL, extending its reach to those who need to author and understand domain ontologies but for whom descriptions logics are difficult to comprehend even when expressed in more user-friendly forms such as the Manchester Syntax.The paper outlines the main grammatical aspects of Rabbit, which can be broadly classified into declarations, concept descriptions and definitions, and elements to support interoperability between ontologies. The paper also describes the human subject testing that has been performed to date and indicates the changes currently being made to the language following this testing. Further modifications have been based on practical experience of the application of Rabbit for the development of operational ontologies in the domain of topography. Forest -and when I say thinking I mean thinking -you and I must do it." A. A. Milne