IF-Map fact-file

What's the problem?

Current ontology mapping mechanisms are not based on strong theoretical grounds; they are difficult to replicate in different settings as they are embedded in integrated environments for ontology editing or attached to a specific formalism. Most of them, use heuristics that exploit syntactic similarities of ontological constructs but do not take into account their explicit semantics.

Towards a solution

Motivated by these drawbacks, we worked on a method and a theory for ontology mapping and merging. Our approach is based on Information Flow theory which we use as the underlying mathematical foundation for performing ontology mapping. We formalize these mappings in terms of logic infomorphisms. An illustration of the types of ontologies we aim to map and the relation they stand to each other is the following:

We assume that Local ontology 1 and Local ontology 2 are ontologies used by different communities and populated with their instances, while Reference ontology is an agreed understanding for sharing knowledge, and is not supposed to be populated. Global ontology does not exist yet, but will be constructed "on the fly" for the purpose of alignment. The arrow lines linking Reference ontology with Local Ontology 2 and Local ontology 2 denote information flow between these ontologies and are formalized as logic infomorphisms. The dashed arrow lines pointing to Global ontology are the extension of this technology which deals with ontology merging.

We have built a stepwise process to realize this information flow based ontology mapping. It consists of four steps:

ontology harvesting

We acquire ontologies by using a variety of methods: use existing ontologies, download them from ontology libraries, edit them, or harvest them from the Web

translation

IF-Map is declaratively specified in Horn logic and executed with a standard Prolog engine. Therefore, we partially translate a variety of input format to Horn clauses with the aim of a customised translator. We deal with a variety of formats ranging from RDF, KIF, Ontolingua, to native Protege KBs and Prolog KB

infomorphisms generation

Here we process the translated ontology input files and generate infomorphisms, the formal links between similar constructs in both ontology.

display mappings

Finally, we translate the generated infomorphisms to an RDF output that can be accessed by other Semantic Web applications and we store them in a KB for further processing and reference.

The IF-Map process is depicted diagrammatically in the following screenshot (click to enlarge):

Take a Guided Tour

Here's a guided tour to IF-Map:

A 2'48" movie in .avi format (3.8MB) (TSCC codec required) and .mov format (24.9MB)

Try a Demonstration

Most of IF-Map components are accessed programmatically from other tools and there is no GUI demonstration available online. However, you can inspect the produced RDF from an ontology mapping scenario between the AKT Reference ontology and Southampton local ontology:

Results in RDF

Technical requirements

To render the page properly we suggest to view the XMLifyed RDF with an IE browser.

Example Applications

We applied IF-Map to map the AKT Reference ontology onto the Southampton and Edinburgh local ontologies.

Further Reading

Key document:

Y.Kalfoglou, M.Schorlemmer. Information Flow based ontology mapping, In Proceedings of the 1st International Conference on Ontologies, Databases and Application of Semantics (ODBASE'02), Irvine, CA, USA, October 2002

Other relevant documents:

M.Schorlemmer. Duality in knowledge sharing, In Proceedings of the 7th International Symposium on Artificial Intelligence and Mathematics, Fort Lauderdale, Florida, USA, January 2002

J.Barwise, J.Seligman. Information Flow: the logic of distributed systems, Tracts in Theoretical Computer Science 44, Cambridge University Press, ISBN: 0-521-58336-1, 1999

"On Semantic Interoperability and the Flow of Information" M.Schorlemmer, Y.Kalfoglou, ISWC'03 workshop on Semantic Integration, Sanibel Island, FL, USA, October 2003

"IF-Map: an ontology mapping method based on information flow theory" Y.Kalfoglou, M.Schorlemmer, to appear in The Journal on Data Semantics (1)1, LNCS 2800, Springer, 2003

"Ontology mapping: the state of the art" Y.Kalfoglou, M.Schorlemmer, The Knowledge Engineering Review 18(1), 2003

"Using Information-Flow Theory to Enable Semantic Interoperability" M.Schorlemmer, Y.Kalfoglou, Sixth Catalan Conference on Artificial Intelligence (CCIA '03), Palma de Mallorca, Spain, October 2003

Semantic representation

View in the AKT Triplestore Browser or as RDF.

Also available in DOAP RDF (Description Of A Project)