Querying Semantic Web Resources Using TRIPLE Views

Abstract

Resources on the Semantic Web are described by metadata based on some formal or informal ontology. It is a common situation that
casual users are not familiar with a domain ontology in detail. This makes it difficult for such users (or their user tools) to formulate queries to find the relevant resources. Users consider the resources in their specific
context, so the most straightforward solution is to formulate queries in an ontology that corresponds to a user-specific view. We present an
approach based on multiple views expressed in ontologies simpler than the domain ontology. This allows users to query heterogeneous data
repositories in terms of multiple, relatively simple, view ontologies. Ontology developers can define such view ontologies and the corresponding mapping rules. These ontologies are represented in
Semantic Web ontology languages such as RDFS, DAML+OIL, or OWL. We present our approach with examples from the e-learning domain using the Semantic Web query and transformation language TRIPLE.