Interoperability of XML Schema Applications with OWL Domain Knowledge and Semantic Web Tools

Abstract

Abstract. Several standards are expressed using XML Schema syntax, since the XML is the default standard for data exchange in the Internet. However, several applications need semantic support offered by domain ontologies and semantic Web tools like logic-based reasoners. Thus, there is a strong need for interoperability between XML Schema and OWL. This can be achieved if the XML schema constructs are expressed in OWL, where the enrichment with OWL domain ontologies and further semantic processing are possible. After semantic processing, the derived OWL constructs should be converted back to instances of the original schema. We present in this paper XS2OWL, a model and a system that allow the transformation of XML Schemas to OWL-DL constructs. These constructs can be used to drive the automatic creation of OWL domain ontologies and individuals. The XS2OWL transformation model allows the correct conversion of the derived knowledge from OWL-DL back to XML constructs valid according to the original XML Schemas, in order to be used transparently by the applications that follow XML Schema syntax of the standards.

Ontology Mapping and SPARQL Rewriting for Querying Federated RDF Data Sources

“…Let i s be an individual from the source ontology which is mapped to an individual i t from the target ontology. Having a Data Triple Pattern t = (subject, predicate, i s ) with i s in its object part and anything in its predicate and subject parts, we can rewrite it by its object part, using a predefined mapping µ and the function (10).…”

Querying XML Data with SPARQL

“…To do that, appropriate mappings between the OWL ontology (O) and the XML Schema (XS) should exist. These mappings may be produced either automatically, based on our previous work in the XS2OWL framework [9], or manually through some mapping process carried out by a domain expert. However, the definition of mappings between OWL ontologies and XML Schemas is not the subject of this paper.…”

“…That is, the valid correspondences between the OWL and XML Schema language constructs have to be defined in advance. The language level correspondences that have been adopted in this paper are well-accepted in a wide range of data integration approaches [2,4,9,10,11]. In particular, we support mappings that obey the following language level correspondence rules: A class of O corresponds to a Complex Type of XS, a DataType Property of O corresponds to a Simple Element or Attribute of XS, and an Object Property of O corresponds to a Complex Element of XS.…”

“…The framework has been smoothly integrated with the XS2OWL framework [9], thus achieving not only the automatic generation of mappings between XML Schemas and OWL ontologies, but also the transformation of XML documents in RDF format.…”

“…Various attempts have been made in the literature to address the issue of accessing XML data from within Semantic Web Environments [2,4,5,6,7,8,9,10,11,12]. An extended overview of related work can be found at [13].…”