We’ve made some recent improvements and bug fixes to the Swoogle Semantic Web search engine, the new version of which is hereby known as “Swoogle 2007″. PhD student Lushan Han is the one who did all of the heavy lifting for this — thanks Lushan!

The biggest change is that Swoogle’s IR index is now updated incrementally, as new or modified Semantic Web documents are processed. When Swoogle processes an RDF document, it analyzes it to extract metadata, and then adds or updates the metadata in Swoogle’s database as well as (re-) indexes information about the document in Swoogle’s IR engine. Previously, these information in the database was updated as documents were found but the IR index was regenerated periodically in an off line batch process. Consequently, the two were not completely synchronized. They are now, at least on a daily basis.

If you want to see the documents that were added or updated today, you can use a term like “hasDateCache:2007-07-11″ in your search. For example, this query finds new or changed RDF documents that were discovered today that use the foaf namespace.

Among the bug fixes getting the “sort by date” option to work correctly on all pages of the result set, fixing the url: qualifier in Swoogle queries, and some memory leaks.

Finally, we had been putting off some changes because we were running out of disk space for Swoogle. We have new hardware that gives us room to grow.

Categories: Uncategorized, , Related posts: • Swoogle is dead, long live Swoogle;  • Not your usual Swoogle;  • Interruptions in Swoogle services;   Comments: none