The notion of RDF Named Graphs has been proposed in order to assign provenance information to data described using RDF triples. In this paper, we argue that named graphs alone cannot capture provenance information in the presence of RDFS reasoning and updates. In order to address this problem, we introduce the notion of RDF/S Graphsets: a graphset is associated with a set of RDF named graphs an...

We present Rubya, a tool that automatically generates the RDF view defined on top of relational data and all rules required for the incremental maintenance of the RDF view. Our approach relies on the designer to specify a mapping between the relational schema and a target ontology and results in a specification of how to represent relational schema concepts in terms of RDF classes and propertie...

One of the most popular applications of Semantic Web technology is the integration of data from distributed locations over the Web. With wrappers, screen scrapers, and information extraction tools it is possible to access, merge, and reason over RDF data from various different, heterogeneous sources. SPARQL can be used to access RDF data in a declarative manner and as will be shown, it can also...

The Semantic Web is an extension of the current Web in which information on the Web is given well-defined meaning, better enabling computers and people to work in cooperation. The technical foundation of the Semantic Web is RDF, a semi-structured data model resembling directed labelled graphs. Semantics of data are given by ontologies that are encoded using a specialized vocabulary called RDF S...

The Semantic Web is an extension of the current Web in which information is given well defined meaning, better enabling computers and people to work in cooperation. The technical foundation of the Semantic Web is RDF, a semi-structured data model resembling directed labelled graphs. Semantics of data are given by ontologies that are encoded using a specialized vocabulary called RDF Schema. Firs...

The next generation of the Web is often characterized as the “Semantic Web”: information will no longer only be intended for human readers, but also for processing by machines, enabling intelligent information services, personalized Web-sites, and semantically empowered search-engines. The Semantic Web requires interoperability on the semantic level. Semantic interoperability requires standards...

In this paper, we describe results of our work in developing transformation tools that enable use of RDF-based Semantic Mediation tools for integration of business applications that have implemented XML Schema-based interfaces. Specifically, we are concerned with validating advanced Semantic Mediation solutions that required XML to RDF, RDF to XML, and the XML Schema to the RDF Schema transform...

This paper addresses the problem of how to determine the validity and origin of information/knowledge on the web. Knowledge Provenance is proposed to address this problem. Four levels of Knowledge Provenance are introduced: Static, where the validity of knowledge does not change over time; Dynamic, where validity may change over time; Uncertain, where the validity of knowledge is uncertain; and...

The lack of a good understanding of customer needs within eservice initiatives caused severe financial losses in the Norwegian energy sector, resulting in the failure of e-service initiatives offering packages of independent services. One of the causes was a poor elicitation and understanding of the e-services at hand. In this paper, we propose an ontologically founded approach (1) to describe ...

Starting from the general framework for Annotated RDFS which we presented in previous work (extending Udrea et al’s Annotated RDF), we address the development of a query language – AnQL – that is inspired by SPARQL, including several features of SPARQL 1.1. As a side effect we propose formal definitions of the semantics of these features (subqueries, aggregates, assignment, solution modifiers) ...