Size Reduction of Multitape Automata

  • Hellis Tamm
  • Matti Nykänen
  • Esko Ukkonen
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3845)


We present a method for size reduction of two-way multitape automata. Our algorithm applies local transformations that change the order in which transitions concerning different tapes occur in the automaton graph, and merge suitable states into a single state. Our work is motivated by implementation of a language for string manipulation in database systems where string predicates are compiled into two-way multitape automata. Additionally, we present a (one-tape) NFA reduction algorithm that is based on a method proposed for DFA minimization by Kameda and Weiner, and apply this algorithm, combined with the multitape automata reduction algorithm, on our multitape automata.


Size Reduction Reduction Algorithm Automaton State Outgoing Transition Future Transition 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Hellis Tamm
    • 1
  • Matti Nykänen
    • 1
  • Esko Ukkonen
    • 1
  1. 1.Department of Computer ScienceUniversity of HelsinkiFinland

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