OntRel: An Ontology Indexer to Store OWL-DL Ontologies and Its Instances

Ontology is one of the most important components of a semantic based information system which provides context to the document. Ontology enables us to capture the semantics of documents. To interpret information and perform reasoning we require storing Ontologies in a way that is correct, consistent, scalable and efficient to retrieve. RDBMS (Relational Database Management Systems) is the most efficient and reliable Data Structure in terms of storage and retrieval. One of the ways is to store Ontologies in RDBMS. OWL is used to represent ontologies. To store OWL documents in RDBMS multiple techniques have been proposed, but they either deal with single ontology or they do not store complete semantics expressed in OWL ontologies which compromise the correct retrieval of the data. Some of the techniques are not really scalable, as the ontology is dynamic and extensible where as the RDBMS schema is not dynamically extensible. So, there is a need to preserve the dynamic OWL documents in the Relational structure in such a way that no data or relationship is lost and advantages of RDBMS are also gained. This paper addresses the issue of storing multiple OWL ontologies in an RDBMS in a way that is correct, consistent, scalable and efficient to retrieve. A relational schema, with the name of OntRel, has been proposed along with a set of rules to populate database from OWL documents. OntRel has been implemented and tested and available as on the web for open use. Finally, we have compared the Load time, Query performance and completeness of OntRel with other indexing techniques using Lehigh University Benchmark (LUBM) and University Ontology Benchmark (UOBM).

[1]  Dominique Lenne,et al.  KoMIS: An Ontology-Based Knowledge Management System for Industrial Safety , 2007 .

[2]  Jeff Heflin,et al.  LUBM: A benchmark for OWL knowledge base systems , 2005, J. Web Semant..

[3]  Jeff Heflin,et al.  DLDB: Extending Relational Databases to Support Semantic Web Queries , 2003, PSSS.

[4]  José Francisco Aldana Montes,et al.  A Tool for Storing OWL Using Database Technology , 2005, OWLED.

[5]  Jeff Heflin,et al.  DLDB2: A Scalable Multi-perspective Semantic Web Repository , 2008, 2008 IEEE/WIC/ACM International Conference on Web Intelligence and Intelligent Agent Technology.

[6]  Ian Horrocks,et al.  The Instance Store: Description Logic Reasoning with Large Numbers of Individuals , 2004 .

[7]  Dimitrios Tektonidis,et al.  ONAR: An Ontologies-based Service Oriented Application Integration Framework , 2006 .

[8]  I. Horrocks,et al.  The Instance Store: DL Reasoning with Large Numbers of Individuals , 2004, Description Logics.

[9]  Chun-Hee Lee,et al.  An Efficient and Scalable Management of Ontology , 2007, DASFAA.

[10]  Irina Astrova,et al.  Storing OWL Ontologies in SQL Relational Databases , 2007 .

[11]  Li Ma,et al.  Minerva: A Scalable OWL Ontology Storage and Inference System , 2006, ASWC.

[12]  Frank van Harmelen,et al.  Sesame: A Generic Architecture for Storing and Querying RDF and RDF Schema , 2002, SEMWEB.

[13]  Lina Nemuraite,et al.  TRANSFORMING ONTOLOGY REPRESENTATION FROM OWL TO RELATIONAL DATABASE , 2006 .

[14]  Young-Sik Jeong,et al.  Persistent Storage System for Efficient Management of OWL Web Ontology , 2007, UIC.

[15]  Hyoil Han,et al.  PIES: A Web Information Extraction System Using Ontology and Tag Patterns , 2005, WAIM.

[16]  L. Stein,et al.  OWL Web Ontology Language - Reference , 2004 .

[17]  Li Ma,et al.  Towards a Complete OWL Ontology Benchmark , 2006, ESWC.

[18]  Enrico Motta,et al.  SemSearch: A Search Engine for the Semantic Web , 2006, EKAW.

[19]  Katsumi Tanaka,et al.  An Effective and Secure Search of Office Documents , 2007 .