Knowledge Media Institute, The Open University, Milton Keynes, UK
{M.Dzbor, J.B.Domingue, E.Motta} @open.ac.uk
Abstract. Web browsing involves two tasks: finding the right web page and then making sense of its content. So far, research has focused on supporting the task of finding web resources through 'standard' information retrieval mechanisms, or semantics-enhanced search. Much less attention has been paid to the second problem. In this paper we describe Magpie, a tool which supports the interpretation of web pages. Magpie offers complementary knowledge sources, which a reader can call upon to quickly gain access to any background knowledge relevant to a web resource. Magpie automatically associates an ontology-based semantic layer to web resources, allowing relevant services to be invoked within a standard web browser. Hence, Magpie may be seen as a step towards a semantic web browser. The functionality of Magpie is illustrated using examples of how it has been integrated with our lab's web resources.
The semantic capabilities of Magpie are achieved by creating a semantic layer over a standard HTML web page. The layer is based on a particular ontology selected by the user, and associated semantic services. In the context of our paper, the services are defined separately from the ontology, and are loosely linked to the ontological hierarchy. This enables Magpie to provide different services depending on the type of a particular semantic entity that occurs in the text. In addition to this shallow semantics, one of the key contributions of the Magpie architecture is its ability to facilitate bi-directional communication between the client and server/service provider. This is achieved through so-called trigger services, which may feature complex reasoning using semantic entities from the user-browsed pages as data source. Triggers use ontology to recognize interesting data patterns in the discovered entities, and bring forward semantically related information to the user. The key benefit of this approach is that there may be no explicit relationship expressed in the web page - the relevance is established implicitly by consulting a particular ontology.
In Proceedings of the 2nd International Semantic Web Conference 2003 ( ISWC 2003), 20-23 October 2003, Sundial Resort, Sanibel Island, Florida, USA