Comparison of Two Versions of Formalization Method for Text Expressed Knowledge

  • Martina Asenbrener Katic
  • Sanja Candrlic
  • Mile Pavlic
Conference paper
Part of the Communications in Computer and Information Science book series (CCIS, volume 716)


The Node of Knowledge (NOK) method is a method for knowledge representation. It is used as a basis for development of formalism for textual knowledge representation (FNOK). Two versions of formalization methods and, respectively, two Question Answering (QA) systems are developed. The first system uses grammars; it is written and implemented in Python. The second, improved system is based on storing text in relational databases without losing semantics and it is implemented in Oracle.

This paper presents the results of comparison of the two QA systems. The first system was tested using 42 sentences. It received 88 questions from users and provided answers. After improving the formalization method, the second system was tested with the same set of sentences and questions. The paper presents the results of the testing, the comparison of answers received from both systems and the analysis of correctness of the answers received.


NOK Node of Knowledge Relational database Question answering systems Knowledge Knowledge-based systems 



The research has been conducted under the project “Extending the information system development methodology with artificial intelligence methods” (reference number supported by University of Rijeka (Croatia).


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Martina Asenbrener Katic
    • 1
  • Sanja Candrlic
    • 1
  • Mile Pavlic
    • 1
  1. 1.Department of InformaticsUniversity of RijekaRijekaCroatia

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