Now showing items 1-14 of 14

    • dlvhex-sparql: A SPARQL-compliant query engine based on dlvhex 

      Polleres, Axel (CEUR, 2007)
      This paper describes the dlvhex SPARQL plugin, a query processor for the upcoming Semantic Web query language standard by W3C. We report on the implementation of this languages using dlvhex, a flexible plugin system ...
    • Entailment for Domain-restricted RDF 

      Polleres, Axel (Springer, 2008)
      We introduce domain-restricted RDF (dRDF) which allows to associate an RDF graph with a fixed, finite domain that interpretations for it may range over. We show that dRDF is a real extension of RDF and discuss impacts on ...
    • inContext: A Pervasive and Collaborative Working Environment for Emerging Team Forms 

      Polleres, Axel (2008)
      Participants in current team collaborations belong to different organizations, work on multiple objectives at the same time, and frequently change locations. They use different devices and infrastructures in collaboration ...
    • Previewing Semantic Web Pipes 

      Phuoc, Danh Le; Polleres, Axel; Samwald, Matthias; Tummarello, Giovanni (Springer, 2008)
      In this demo we present a first implementation of Semantic Web Pipes, a powerful tool to build RDF-based mashups. Semantic Web pipes are defined in XML and when executed they fetch RDF graphs on the Web, operate on them, ...
    • Processing ontology alignments with SPARQL 

      Polleres, Axel (IEEE, 2008)
      Solving problems raised by heterogeneous ontologies can be achieved by matching the ontologies and processing the resulting alignments. This is typical of data mediation in which the data must be translated from one ...
    • Quantified equilibrium logic and hybrid rules 

      Polleres, Axel (Springer, 2007)
      In the ongoing discussion about combining rules and Ontologies on the Semantic Web a recurring issue is how to combine first-order classical logic with nonmonotonic rule languages. Whereas several modular approaches to de- ...
    • A rule system for querying persistent RDFS data 

      Krennwallner, Thomas; Martello, Alessandra; Polleres, Axel (2009)
      We present GiaBATA, a system for storing, aggregating, and querying Semantic Web data, based on declarative logic programming technology, namely on the dlvhex system, which allows us to implement a fully SPARQL compliant ...
    • SAOR: Authoritative Reasoning for the Web 

      Hogan, Aidan; Harth, Andreas; Polleres, Axel (Springer, 2008)
      In this paper we discuss the challenges of performing reasoning on large scale RDF datasets from the Web. We discuss issues and practical solutions relating to reasoning over web data using a rule-based approach to ...
    • Scalable Authoritative OWL Reasoning for the Web 

      Hogan, Aidan; Harth, Andreas; Polleres, Axel (2009)
    • Scalable Authoritative OWL Reasoning on a Billion Triples 

      Hogan, Aidan; Harth, Andreas; Polleres, Axel (2008)
      In this paper we present a scalable algorithm for performing a subset of OWL reasoning over web data using a rule-based approach to forward-chaining; in particular, we identify the problem of ontology hijacking: new ...
    • SPARQL++ for mapping between RDF vocabularies 

      Polleres, Axel (Springer, 2007)
      Lightweight ontologies in the formof RDF vocabularies such as SIOC, FOAF, vCard, etc. are increasingly being used and exported by ¿serious¿ applications recently. Such vocabularies, together with query languages like SPARQL ...
    • Towards Fine-grained Service Matchmaking by Using Concept Similarity 

      Polleres, Axel (2007)
      Several description frameworks to semantically describe and match services on the one hand and service requests on the other have been presented in the literature. Many of the current proposals for defining notions of ...
    • Who the FOAF knows Alice? A needed step towards Semantic Web Pipes 

      Polleres, Axel; Tummarello, Giovanni (2007)
      In this paper we take a view from the bottom to RDF(S) reasoning. We discuss some issues and requirements on reasoning towards effectively building SemanticWeb Pipes, aggregating RDF data from various distributed sources. ...
    • XSPARQL: Traveling between the XML and RDF worlds - and avoiding the XSLT pilgrimage 

      Akhtar, Waseem; Krennwallner, Thomas; Polleres, Axel (Springer, 2008)
      With currently available tools and languages, translating between an existing XML format and RDF is a tedious and error-prone task. The importance of this problem is acknowledged by the W3C GRDDL working group who faces ...