Now showing items 1-20 of 26

    • Building a Semantic Web Search Engine: Challenges and Solutions 

      Harth, Andreas; Hogan, Aidan; Umbrich, Jürgen; Decker, Stefan (2008)
      Current web search engines return links to documents for user-specified keywords queries. Users have to then manually trawl through lists of links and glean the required information from documents. In contrast, semantic ...
    • DRETa: extracting RDF from wikitables 

      Muñoz, Emir; Hogan, Aidan; Mileo, Alessandra (CEUR-WS.org, 2013)
      Tables are widely used in Wikipedia articles to display relational information - they are inherently concise and information rich. However, aside from info-boxe s, there are no automatic methods to exploit the integrated ...
    • The ExpertFinder Corpus 2007 for the Benchmarking and Development of ExpertFinding Systems 

      Hogan, Aidan; Harth, Andreas (2007)
      We provide a benchmark dataset for expert finding within the computer science domain. We show how large isolated data graphs from disparate structured data sources can be combined to form one, large, well-linked RDF graph ...
    • Four Heuristics to Guide Structured Content Crawling 

      Umbrich, Jürgen; Harth, Andreas; Hogan, Aidan; Decker, Stefan (2008)
      Search engines focusing on particular media types face difficulties in discovering suitable URIs on the Web. Since the engines are only interested in a small fraction of the Web, a crawler should use heuristics to concentrate ...
    • Freshening up while Staying Fast: Towards Hybrid SPARQL Queries 

      Umbrich, Jürgen; Karnstedt, Marcel; Hogan, Aidan; Parreira, Josiane Xavier (2012)
    • Hybrid SPARQL queries: fresh vs. fast results 

      Umbrich, Jurgen; Karnstedt, Marcel; Hogan, Aidan; Parreira, Xavier (2012)
    • Linked Data and the Semantic Web Standards 

      Hogan, Aidan (Chapman and Hall / CRC Press, 2013)
      On the traditional World Wide Web we all know and love, machines are used as brokers of content: they store, organize, request, route, transmit, receive and display content encapsulated as documents. In order for machines ...
    • On the Ostensibly Silent 'W' in OWL 2 RL 

      Hogan, Aidan; Decker, Stefan (Springer, 2009)
      In this paper, we discuss the draft OWL 2 RL proable from the perspective of applying the constituent rules over Web data. In particular, borrowing from previous work, we discuss (i) optimisations based on a separation ...
    • Performing Object Consolidation on the Semantic Web Data Graph 

      Hogan, Aidan; Harth, Andreas; Decker, Stefan (2007)
      An important aspect of Semantic Web technologies is the issue of identity and uniquely identifying resources, which is essential for integrating data across sources. Currently, there is poor agreement on the use of ...
    • Podcast Pinpointer: A Multimedia Semantic Web Application 

      Hogan, Aidan; Harth, Andreas; Breslin, John (IEEE, 2005)
      In late 2004, a new method of publishing multimedia broadcasts on the Internet became popular called `Podcasting¿. Podcasting incorporates existing feed description formats, namely RSS 2.0, to ...
    • RDFS & OWL Reasoning for Linked Data 

      Hogan, Aidan; Delbru, Renaud; Umbrich, Jurgen (na, 2013)
      Linked Data promises that a large portion of Web Data will be usable as one big interlinked RDF database against which structured queries can be answered. In this lecture we will show how reasoning - using RDF Schema (RDFS) ...
    • ReConRank: A Scalable Ranking Method for Semantic Web Data with Context 

      Hogan, Aidan; Harth, Andreas; Decker, Stefan (2006)
      We present an approach that adapts the well-known PageRank/HITS algorithms to Semantic Web data. Our method combines ranks from the RDF graph with ranks from the context graph, i.e. data sources and their linkage. We present ...
    • SAFE: SPARQL federation over RDF data cubes with access control 

      Khan, Yasar; Saleem, Muhammad; Mehdi, Muntazir; Hogan, Aidan; Mehmood, Qaiser; Rebholz-Schuhmann, Dietrich; Sahay, Ratnesh (BioMed Central, 2017-02-01)
      Several query federation engines have been proposed for accessing public Linked Open Data sources. However, in many domains, resources are sensitive and access to these resources is tightly controlled by stakeholders; ...
    • 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 Web-Querying Infrastructure: Ready for Action? 

      Hogan, Aidan (2013)
      Hundreds of public SPARQL endpoints have been deployed on the Web, forming a novel decentralised infrastructure for querying billions of structured facts from a variety of sources on a plethora of topics. But is this ...
    • SPORTAL: Profiling the Content of Public SPARQL Endpoints 

      Hasnain, Ali; Mehmood, Qaiser; Sana e Zainab, Syeda; Hogan, Aidan (IGI Global, 2016)
      Access to hundreds of knowledge bases has been made available on the Web through public SPARQL endpoints. Unfortunately, few endpoints publish descriptions of their content (e.g., using VoID). It is thus unclear how agents ...
    • SPORTAL: Searching for Public SPARQL Endpoints 

      Hasnain, Ali; Mehmood, Qaiser; Zainab, Syeda Sana e; Hogan, Aidan (NUI Galway, 2016-10)
      There are hundreds of SPARQL endpoints on the Web, but finding an endpoint relevant to a client s needs is difficult: each endpoint acts like a black box, often without a description of its content. Herein we briefly ...
    • SWSE: Answers Before Links! 

      Harth, Andreas; Hogan, Aidan; Delbru, Renaud; Umbrich, Jürgen; O'Riain, Sean; Decker, Stefan (CEUR-WS.org, 2007)
      We present a system that improves on current document- centric Web search engine technology; adopting an entity-centric perspective, we are able to integrate data from both static and live sources into a coherent, interlinked ...