Skip to main content
Log in

Decidability of the minimization of fuzzy tree automata with membership values in complete lattices

  • Original Research
  • Published:
Journal of Applied Mathematics and Computing Aims and scope Submit manuscript

Abstract

The objective of this paper is to introduce a method for constructing a minimal lattice-valued tree automaton with membership values in a totally ordered lattice (in short \(\mathcal {LTA}),\) based on the solvability of a system of fuzzy polynomial equations. Since the minimization problem strongly depends on the equivalence problem, at first, the equivalence problem is examined. For this purpose, the notion of h-equivalence is defined, and a necessary and sufficient condition for the equivalence between two \(\mathcal {LTA}s\) is provided. It is shown that the equivalence problem of \(\mathcal {LTA}s\) is decidable. In the minimization problem, the following question is replied: given an \(\mathcal {LTA}\) \(\mathbb {A}\) and a positive integer k,  is there an \(\mathcal {LTA}\) with k states equivalent to \(\mathbb {A}?\) Decidability of the minimization problem is demonstrated, and an approach to return a minimal \(\mathcal {LTA}\) equivalent to the original one is presented. Also, the time complexity of the proposed algorithm is analyzed. Finally, some examples are presented to clarify the minimization problem.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Abolpour, K.H., Zahedi, M.M., Shamsizadeh, M.: BL-general fuzzy automata and accept behavior. J. Appl. Math. Comput. 38 103–118 (2012)

  2. Babari, P., Droste, M., Perevoshchikov, V.: Weighted register automata and weighted logic on data words. Theoret. Comput. Sci. 744, 3–21 (2018)

    Article  MathSciNet  Google Scholar 

  3. Birkhof, G.: Lattice Theory. American Mathematical Society, Providence (1984)

    Google Scholar 

  4. Bozapalidis, S., Bozapalidoy, O.L.: Fuzzy tree language recognizability. Fuzzy Sets Syst. 161, 716–734 (2010)

    Article  MathSciNet  Google Scholar 

  5. Cheng, W., Mo, Z.W.: Minimization algorithm of fuzzy finite automata. Fuzzy Sets Syst. 141, 439–448 (2004)

    Article  MathSciNet  Google Scholar 

  6. Comon, H., Dauchet, M., Gilleron, R., Jacquemard, F., Lugiez, D., Loding, C., Tison, S., Tommasi, M.: Tree Automata: Technigues and Applications (2007). http://tata.gforge.inria.fr

  7. Doner, J.E.: Tree acceptors and some of their applications. J. Comput. Syst. Sci. 4, 406–451 (1970)

    Article  MathSciNet  Google Scholar 

  8. Doostfatemeh, M., Kremer, S.C.: New directions in fuzzy automata. Int. J. Approx. Reason. 38, 175–214 (2005)

    Article  MathSciNet  Google Scholar 

  9. Dubey, M.K., Tiwari, S.P., Sostak, A.: Categories of quantale-valued fuzzy automata: determinization and minimization. J. Appl. Math. Comput. 63, 771–785 (2020)

    Article  MathSciNet  Google Scholar 

  10. Esik, Z., Liu, G.: Fuzzy tree automata. Fuzzy Sets Syst. 158, 1450–1460 (2007)

    Article  MathSciNet  Google Scholar 

  11. Hogberg, J., Maletti, A., May, J.: Backward and forward bisimulation minimization of tree automata. Theoret. Comput. Sci. 410(37), 3539–3552 (2009)

    Article  MathSciNet  Google Scholar 

  12. Inagaki, Y., Fukumura, T.: On the description of fuzzy meaning of context-free language. In: Fuzzy Sets and Their Applications to Cognitive and Decision Processes, Proc. U.S. Japan Seminar, University of California, Berkeley, CA, 1974, Academic Press, New York (1975), pp. 301–328

  13. Ghorani, M.: On characterization of fuzzy tree pushdown automata. Soft. Comput. 23(4), 1123–1131 (2019)

    Article  Google Scholar 

  14. Ghorani, M.: State hyperstructures of tree automata based on lattice-valued logic. RAIRO-Theor. Inform. Appl. 52(1), 23–42 (2018)

    Article  MathSciNet  Google Scholar 

  15. Ghorani, M.: Tree automata based on complete residuated lattice-valued logic: reduction algorithm and decision problem. Iran. J. Fuzzy Syst. 15(7), 103–119 (2018)

    MathSciNet  MATH  Google Scholar 

  16. Ghorani, M., Zahedi, M.M.: Characterizations of complete residuated lattice-valued finite tree automata. Fuzzy Sets Syst. 199, 28–46 (2012)

    Article  MathSciNet  Google Scholar 

  17. Ghorani, M., Zahedi, M.M.: Alternating regular tree grammars in the framework of lattice-valued logic. Iran. J. Fuzzy Syst. 13(2), 71–94 (2016)

    MathSciNet  MATH  Google Scholar 

  18. Ghorani, M., Zahedi, M.M.: Coding tree languages based on lattice valued logic. Soft. Comput. 21(14), 3815–3825 (2017)

    Article  Google Scholar 

  19. Ghorani, M., Zahedi, M.M., Ameri, R.: Algebraic properties of complete residuated lattice valued tree automata. Soft. Comput. 16(10), 1723–1732 (2012)

    Article  Google Scholar 

  20. Jurvanen, E., Steinby, M.: Fuzzy deterministic top-down tree automata (2019). arXiv:1911.11529v1

  21. Lee, E.T., Zadeh, L.A.: Note on fuzzy languages. Inform. Sci. 1, 421–434 (1969)

    Article  MathSciNet  Google Scholar 

  22. Lei, H.X., Li, Y.: Reduction and minimization algorithm of synchronous lattice-valued automata. Comput. Eng. Appl. 42(16), 57–60 (2006)

    Google Scholar 

  23. Lei, H.X., Li, Y.: Minimization of states in automata theory based on finite lattice-ordered monoids. Inf. Sci. 177, 1413–1421 (2007)

    Article  MathSciNet  Google Scholar 

  24. Li, Y., Ma, Z.: Quantitative computational tree logic model checking based on generalized possibility measures. IEEE Trans. Fuzzy Syst. 23(6), 2034–2047 (2015)

    Article  Google Scholar 

  25. Li, Y.M., Pedrycz, W.: Minimization of lattice finite automata and its application to the decomposition of lattice languages. Fuzzy Sets Syst. 158(13), 1423–1436 (2007)

    Article  MathSciNet  Google Scholar 

  26. Li, L., Qiu, D.: On the state minimization of fuzzy automata. IEEE Trans. Fuzzy Syst. 23(2), 434–443 (2015)

    Article  Google Scholar 

  27. Moghari, S., Zahedi, M.M.: Similarity-based minimization of fuzzy tree automata. J. Appl. Math. Comput. 50(1), 417–436 (2016)

    Article  MathSciNet  Google Scholar 

  28. Moghari, S., Zahedi, M.M.: Multidimensional fuzzy finite tree automata. Iran. J. Fuzzy Syst. 16(5), 155–167 (2019)

    MathSciNet  MATH  Google Scholar 

  29. Mordeson, J.N., Malik, D.S.: Fuzzy Autom. Lang. Theory Appl. Chapman & Hall CRC, London, BocaRaton (2002)

    Google Scholar 

  30. Pan, H.Y., Li, Y., Cao, Y.Z., Ma, Z.: Model checking computation tree logic over finite lattices. Theoret. Comput. Sci. 612, 45–62 (2016)

    Article  MathSciNet  Google Scholar 

  31. Qiu, D.W.: Characterizations of fuzzy finite automata. Fuzzy Sets Syst. 141, 391–414 (2004)

    Article  MathSciNet  Google Scholar 

  32. Santos, E.S.: Maximin automata. Inform. Control 12, 367–377 (1968)

    Article  MathSciNet  Google Scholar 

  33. Santos, E.S.: On reduction of maxmin machines. J. Math. Anal. Appl. 37, 677–686 (1972)

    Article  MathSciNet  Google Scholar 

  34. Shamsizadeh, M., Zahedi, M.M.: Bisimulation of type 2 for BL-general fuzzy automata. Soft. Comput. 23(20), 9843–9852 (2019)

    Article  Google Scholar 

  35. Thatcher, J.W., Wright, J.B.: Generalized finite automata theory with an application to a decision-problem of second order logic. Math. Syst. Theory 2, 57–81 (1968)

    Article  MathSciNet  Google Scholar 

  36. Thomason, M.G., Marinos, P.N.: Deterministic acceptors of regular fuzzy languages. IEEE Trans. Syst. Man Cybern. 4 (1974) 228–230

  37. Wee, W.G., Fu, K.S.: A formulation of fuzzy automata and its application as a model of learning systems. IEEE Trans. Systems Man Cybern. 5, 215–223 (1969)

    MATH  Google Scholar 

  38. Wu, L., Qiu, D.W.: Automata theory based on completed residuated lattice-valued logic: reduction and minimization. Fuzzy Sets Syst. 161, 1635–1656 (2010)

    Article  Google Scholar 

  39. Xing, H.Y., Qiu, D.W., Liu, F.C., Fan, Z.J.: Equivalence in automata theory based on complete residuated lattice-valued logic. Fuzzy Sets Syst. 158, 1407–1422 (2007)

    Article  MathSciNet  Google Scholar 

Download references

Funding

The authors declare that no funding was received.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Maryam Ghorani.

Ethics declarations

Conflict of interest

The authors declare that they have no conflict of interest.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Ghorani, M., Moghari, S. Decidability of the minimization of fuzzy tree automata with membership values in complete lattices. J. Appl. Math. Comput. 68, 461–478 (2022). https://doi.org/10.1007/s12190-021-01529-6

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12190-021-01529-6

Keywords

Mathematics Subject Classification

Navigation