Monday, April 14, 2008

Linking to DBpedia with TopBraid

The semantic Web is coming. After at least a decade of preparation in its research community, the technology around RDF seems to be finally taking off. Re-branded as a web of linked data, the semantic Web is bootstrapping itself around a growing network of online databases, ontologies, SPARQL end-points, RDFa files and RDF-compliant web services.

A promising central hub in this linked data network is DBpedia, an RDF repository based on Wikipedia. DBpedia provides machine-readable RDF data for each of the pages in Wikipedia. Each Wikipedia page is represented by a corresponding RDF resource, and these resources are associated with RDF property values to provide descriptions, images, cross-references and tons of useful background knowledge. For example, the DBpedia pages for cities (e.g., Canberra) contain geographical information, the number of inhabitants, population density, links to famous inhabitants and average temperatures, all in machine-processable form. While these property values may not be totally stable and reliable, they are at least a good start.

However, the main benefit of DBpedia is that it provides relatively stable URIs for all relevant real-world concepts. This makes it a natural place to connect specific domain models with each other. If I publish my RDF files with links to DBpedia and you do the same, then we can automatically find cross-references and might more easily find mappings between our domain models. All I need to do is to add links such as { my:Canberra owl:sameAs dbpedia:Canberra }.

In order to support linking domain models with DBpedia and to encourage our users to link their domain models into the semantic Web, TopBraid Composer 2.5.3 contains some new features that semi-automatically suggest missing links. We have integrated a Wikipedia web service that takes a string (here, an rdfs:label or a local resource name) and tries to find a matching Wikipedia page for it. From the resulting page, TopBraid can derive the DBpedia page and display it in a Wizard as shown below. The wizard can then be used to preview and assign DBpedia links to one or more domain resources.




I have made a short video about all this.