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A Logic-Based Tool for Semantic Information Extraction

  • Massimo Ruffolo
  • Marco Manna
  • Lorenzo Gallucci
  • Nicola Leone
  • Domenico Saccà
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4160)

Abstract

Recognizing and extracting meaningful information from unstructured Web documents, taking into account their semantics, is an important problem in information and knowledge management. This paper describes H\(\imath\)LεX, a system implementing a novel logic-based approach to information extraction from unstructured documents. The approach adopted in the H\(\imath\)LεX system is founded on a new two-dimensional representation of documents, and heavily exploits DLP  +  – an extension of disjunctive logic programming for ontology representation and reasoning, which has been recently implemented on top of the DLV system. Unlike previous systems, which are mainly syntactic, H\(\imath\)LεX combines both semantic and syntactic knowledge for a powerful information extraction. Ontologies, representing the semantics of the domain of the information to be extracted, are encoded in DLP  + , while the extraction patterns are encoded by regular expressions in an ad hoc two-dimensional grammar. These regular expressions are (internally) translated into DLP  +  rules, whose execution yields the actual extraction of information from the input document. H\(\imath\)LεX allows the semantic information extraction from both HTML pages and flat text documents. The usefulness of Hilex has been already confirmed also in practice, as the system has been successfully employed in two advanced applications in the e-health and e-finance domains.

Keywords

Regular Expression Information Extraction Domain Ontology Input Document Italian National Research Council 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Massimo Ruffolo
    • 1
    • 3
  • Marco Manna
    • 4
  • Lorenzo Gallucci
    • 1
  • Nicola Leone
    • 1
    • 4
  • Domenico Saccà
    • 1
    • 2
    • 3
  1. 1.Exeura s.r.l. 
  2. 2.DEIS – Department of Electronics, Computer Science and Systems 
  3. 3.ICAR-CNR – Institute of High Performance Computing and Networking, of the Italian National Research Council 
  4. 4.Department of MathematicsUniversity of CalabriaArcavacata di Rende (CS)Italy

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