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Abstract. The SPIRIT search engine provides a test bed for the development of web search technology that is specialised for access to geographical information. Major components include the user interface, geographical ontology, maintenance and retrieval functions for a test collection of web documents, textual and spatial indexes, relevance ranking and metadata extraction. Here we summarise the functionality and interaction between these components before focusing on the design of the geo-ontology and the development of spatio-textual indexing methods. The geo-ontology supports functionality for disambiguation, query expansion, relevance ranking and metadata extraction. Geographical place names are accompanied by multiple geometric footprints and qualitative spatial relationships. Spatial indexing of documents has been integrated with text indexing through the use of spatio-textual keys in which terms are concatenated with spatial cells to which they relate. Preliminary experiments demonstrate considerable performance benefits when compared with pure text indexing and with text indexing followed by a spatial filtering stage.

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2012. What can I do there? Towards the automatic discovery of place-related services and activities. International Journal of Geographical Information Science 26 (2) , pp.

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This paper focuses on the consistency issues related to integrating multiple sets of spatial data in spatial information systems such as Geographic Information Systems (GISs). Data sets to be integrated are assumed to hold information about the same geographic features which can be drawn from di erent sources at di erent times, which may vary in reliability and accuracy, and which may vary in the scale of presentation resulting in possible multiple spatial representations for these features. A systematic approach is proposed which relies rst on breaking down the consistency issue by i d e n t i f ying a range of consistency classes which can be checked in isolation. These classes are a representative set of properties and relationships which can completely identify the geographic objects in the data sets. Di erent levels of consistency are then proposed, namely, total, partial and conditional, which can be checked for every consistency class. This provides the exibility for two data sets to be integrated without necessarily being totally consistent in every aspect. The second step of the proposed approach is to explicitly represent the di erent classes and levels of consistency in the system. As an example, a simple structure which stores adjacency relationships is given which can be used for the explicit representation of topological consistency. The paper also proposes that the set of consistent knowledge in the data sets (which is mostly qualitative) be explicitly represented in the database and that uncertainty or ambiguity inherent in the knowledge be represented as well.