This paper describes a sublanguage of Casl, called CaslDL, that corresponds to the Web Ontology Language (OWL) being used for the semantic web. OWL can thus benefit from Casl’s strong typing discipline and powerful structuring concepts. Vice versa, the automatic decision procedures available for OWL DL (or more precisely, the underlying description logic SHOIN (D)) become available for a sublan...

Recently, there have been a number of proposals for languages for expressing web service constraints and capabilities, with WSPolicy and WSPL leading the way. The proposed languages, although relatively inexpressive, suffer from a lack of formal semantics. In this paper, we provide a mapping of WS-Policy to the description logic fragment species of the Web Ontology Language (OWL-DL), and descri...

We propose a new technique for approximate ABox reasoning with OWL DL ontologies. Essentially, we obtain substantially improved reasoning performance by disregarding non-Horn features of OWL DL. Our approach comes as a side-product of recent research results concerning a new transformation of OWL DL ontologies into negation-free disjunctive datalog [1, 2, 3, 4], and rests on the idea of perform...

This paper discusses an approach to modeling monolingual and bilingual dictionaries in the description logic species of the OWL Web Ontology Language (OWL DL). The central idea is that the model of a bilingual dictionary is a combination of the models of two monolingual dictionaries, in addition to an abstract translation model. The paper addresses the advantages of using OWL DL for the design ...

This report presents three tracks of research on Attempto Controlled English (ACE). First, we show how ACE can be translated into OWL DL and how OWL DL can be verbalized in ACE. Second, we describe work done in cooperation with the working group A2 Bioinformatics on using ACE as ontology language for protein interactions. Third, we summarise changes to ACE and its associated tools. Keyword List...

In this work, we address the problem of revision of OWL-DL knowledge bases. We focus on belief bases revision as it has previously been shown that OWL-DL is not AGM-compliant for revision. Previously an algorithm for belief base semi-revision for propositional logic has been defined; in particular it has been shown how the diagnosis problem can be translated into a revision problem. In this wor...

Rewriting-based approaches for answering queries over an OWL 2 DL ontology have so far been developed mainly for Horn fragments of OWL 2 DL. In this paper, we study the possibilities of answering queries over non-Horn ontologies using datalog rewritings. We prove that this is impossible in general even for very simple ontology languages, and even if PTIME = NP. Furthermore, we present a resolut...

Description logics (DLs) have recently been used to provide access to large amounts of data through a high-level conceptual interface, which is of relevance to both data integration and ontology-based data access. The fundamental inference service in this case is answering queries by taking into account the axioms in the TBox and the data stored in the ABox. The key property for such an approac...

While it has been argued that knowledge representation for the World Wide Web must respect the open world assumption due to the “open” nature of the Web, users of the Web Ontology Language (OWL) have often requested some form of non-monotonic reasoning. In this paper, we present preliminary optimizations and an implementation of a restricted version of Reiter’s default logic as an extension to ...

Using SPARQL for writing queries on OWL-DL ontologies can be complicated due to its RDF triple semantics. Translating OWL expressions to this semantics is a non-trivial problem. We present SPARQLDL Abstract Syntax (SPARQLAS), a proper subset of SPARQL, to solve this issue by employing the OWL Functional-Style Syntax to compose queries. We illustrate how the translation is made possible by a mod...