Search results for "Open-world assumption"
showing 2 items of 2 documents
UML Style Graphical Notation and Editor for OWL 2
2010
OWL is becoming the most widely used knowledge representation language. It has several textual notations but no standard graphical notation apart from verbose ODM UML. We propose an extension to UML class diagrams (heavyweight extension) that allows a compact OWL visualization. The compactness is achieved through the native power of UML class diagrams extended with optional Manchester encoding for class expressions thus largely eliminating the need for explicit anonymous class visualization. To use UML class diagram notation we had to modify its semantics to support Open World Assumption that is central to OWL. We have implemented the proposed compact visualization for OWL 2 in a UML style …
From Databases to Ontologies
2009
This chapter introduces the UML profile for OWL as an essential instrument for bridging the gap between the legacy relational databases and OWL ontologies. We address one of the long-standing relational database design problems where initial conceptual model (a semantically clear domain conceptualization ontology) gets “lost” during conversion into the normalized database schema. The problem is that such “loss” makes database inaccessible for direct query by domain experts familiar with the conceptual model only. This problem can be avoided by exporting the database into RDF according to the original conceptual model (OWL ontology) and formulating semantically clear queries in SPARQL over t…