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On the lengths of values in a finite transducer

  • Andreas Weber
Communications
Part of the Lecture Notes in Computer Science book series (LNCS, volume 379)

Abstract

The length-degree of a normalized finite transducer (NFT) M is the minimal nonnegative d such that each input word of M only has values with at most d different lengths — or is infinite, depending on whether or not such a d exists. Using the notion of the length-degree, we present some basic results on the lengths of values in a finite transducer. The strongest of these results is: A generalized sequential machine (GSM) with finite length-degree can be effectively decomposed into finitely many GSM's M1,...,MN with length-degree one such that the relation realized by M is the union of the relations realized by M1,...,MN. Using this decomposition, we demonstrate that the equivalence of GSM's with finite length-degree is decidable. By reduction, both results can be easily generalized to NFT's.

Keywords

Polynomial Time Short Form Decomposition Theorem Equivalence Problem Finite Automaton 
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 1989

Authors and Affiliations

  • Andreas Weber
    • 1
  1. 1.Fachbereich InformatikJ.W. Goethe-UniversitätFrankfurt am MainWest Germany

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