Conceptual Normalisation of XML Data for Interoperability in Tourism

Currently many tourism systems and standardisation initiatives adopt XML as a standard for data representation. Together with XML, XML Schema definition language is becoming more widely used for describing the structure and constraining the contents of the documents. However neither XML itself nor XML Schema provides sufficient mechanisms for the representation of data semantics. In this paper we discuss the issue of conceptual normalisation of XML documents. Conceptual normalisation is introduced as a pre-processing step of our ontology-mediated framework for the harmonisation of electronic tourism systems. We propose to use RDF Schema as a mechanism for conceptual modelling of data sources and investigate the relation between semantics carrying constructs of XML Schema and RDF Schema. Accordingly we elaborate on the idea of transforming XML data into a conceptual model corresponding to RDF statements and vice-versa. Finally we propose a declarative solution and a high-level architecture of a toolkit facilitating this process.