Masters Thesis Defense "Rules with Right Hand Existential or Disjunction with ROWLTab" by Sri Jitendra Satpathy

Committee:  Drs. Pascal Hitzler, Advisor, Mateen Rizki, and Yong Pei

ABSTRACT:

One hotly debated research topic is, "What is the best approach for modeling ontologies?" In the earlier stages of modeling ontologies, researchers have favored the usage of description logic to capture knowledge. One such choice is the Web Ontology Language (OWL) that is based on description logic. Many tools were designed around this principle and are still widely being used to model and explore ontologies. However, not all users find description logics to be intuitive, at least not without an extensive background in formal logics. Due to this, researchers have tried to explore other ways that will enable such users to model ontologies intuitively. This led researchers to explore a rule-based paradigm. For many users this approach was found to be a more natural and intuitive way of representing knowledge. Hence, Semantic Web Rule Language (SWRL) became an extremely popular choice among researchers and naive users. However, one major problem with SWRL is that machines cannot readily process it. Therefore, researchers at Data Semantics Laboratory (DaSe Lab) created an interactive plugin, called ROWLTab, that efficiently converts rules into OWL axioms. This plugin allows a user to create ontologies using SWRL syntax and convert it into OWL axioms. However, the tool does not support translation of rules that contains a disjunction and existential quantifiers in the consequent.

In this paper we will discuss the modifications that were successfully made to the existing plugin to support the translation of right-hand existential and disjunction rules. We posit that this modification gives the user the ability to model more realistic and complex ontologies. Lastly, our evaluation shows that the tool can add 89% of the rules that contains an existential quantifier and 65% of the rules that contains a disjunction. We also discuss why we were unable to insert the remaining rules more in detail.