Size Reduction of Multitape Automata

  • Hellis Tamm
  • Matti Nykänen
  • Esko Ukkonen
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.


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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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