Hellis Tamm

Senior Researcher, Department of Software Science, Tallinn University of Technology

PhD from: Department of Computer Science , University of Helsinki, 2005, advisor prof. Esko Ukkonen

Research interests: automata theory

Publications

  • H. Tamm. Quotients and atoms of reversible languages.
    Theoretical Computer Science, in press, link.

  • H. Tamm. Boolean automata and atoms of regular languages.
    MFCS 2021, August 23-27, 2021, Tallinn, Estonia, LIPIcs 202, 86:1-86:13, link.

  • H. Tamm. Quotients and atoms of reversible languages.
    RPLA 2019, Porto, Portugal, Oct 9, 2019, Springer, LNCS 12233, 443-455, link.

  • H. Tamm, M. Veanes. Theoretical aspects of symbolic automata.
    SOFSEM 2018, Krems an der Donau, Austria, Jan 29 - Feb 2, 2018, Springer, LNCS 10706, 428-441, link.

  • H. Tamm, B. van der Merwe. Lower bound methods for the size of nondeterministic finite automata revisited.
    LATA 2017, Umeå, Sweden, 6-9 March 2017, Springer, LNCS 10168, 261-272, link.

  • H. Tamm. New interpretation and generalization of the Kameda-Weiner method.
    ICALP 2016, Rome, Italy, 12-15 July 2016, Leibniz Int. Proc. in Informatics, vol. 55, art. 116, Dagstuhl Publishing, link.

  • H. Tamm. Generalization of the double-reversal method of finding a canonical residual finite state automaton.
    DCFS 2015, Waterloo, ON, Canada, June 25-27, 2015, Springer, LNCS 9118, 268-279, link.

  • J. Brzozowski, H. Tamm. Theory of átomata.
    Theoretical Computer Science, 539, 2014, 13-27, link.

  • J. Brzozowski, H. Tamm. Complexity of atoms of regular languages.
    International Journal of Foundations of Computer Science, 24 (7), 2013, 1009-1027, link.

  • J. Brzozowski, H. Tamm. Quotient complexities of atoms of regular languages.
    16th Int. Conf. on Developments in Language Theory, DLT 2012,
    Taipei, Taiwan, August 14-17, 2012, Springer, LNCS 7410, 50-61, link.

  • B. van der Merwe, H. Tamm, L. van Zijl. Minimal DFA for symmetric difference NFA.
    14th Int. Workshop on Descriptional Complexity of Formal Systems, DCFS 2012,
    Braga, Portugal, July 23-25, 2012, Springer, LNCS 7386, 307-318, link.

  • J. Brzozowski, H. Tamm. Theory of átomata.
    15th Int. Conf. on Developments in Language Theory, DLT 2011,
    Milan, Italy, July 19-22, 2011, Springer, LNCS 6795, 105-116, link.

  • H. Tamm. Some minimality results on biresidual and biseparable automata.
    4th Int. Conf. on Language and Automata Theory and Applications, LATA 2010,
    Trier, Germany, May 24-28, 2010, Springer, LNCS 6031, 573-584, link.

  • H. Tamm. On transition minimality of bideterministic automata.
    International Journal of Foundations of Computer Science, 19 (3), 2008, 677-690, link.

  • H. Tamm. On transition minimality of bideterministic automata.
    In: Developments in Language Theory : 11th International Conference, DLT 2007,
    Turku, Finland, July 3-6, 2007, Proceedings, Springer, 2007, LNCS 4588, 411-421, link.

  • Tamm, H., Nykänen, M., and Ukkonen, E. On size reduction techniques for multitape automata.
    Theoretical Computer Science, 363(2), 2006, 234-246, link.

  • Tamm, H., Nykänen, M., and Ukkonen, E. Size reduction of multitape automata.
    Proc. 10th Int. Conf. on Implementation and Application of Automata (CIAA 2005),
    LNCS 3845, Springer, 2006, 307-318, link.

  • Tamm, H., and Ukkonen, E.
    Bideterministic automata and minimal representations of regular languages.
    Theoretical Computer Science, 328, 1-2 (2004), 135-149, link.

  • Tamm, H., and Ukkonen, E.
    Bideterministic automata and minimal representations of regular languages.
    Proc. Eighth Int. Conf. on Implementation and Application of Automata (CIAA 2003),
    LNCS 2759, Springer, 2003, 61-71, link.

  • Grahne, G., Hakli, R., Nykänen, M., Tamm, H., and Ukkonen, E.
    Design and implementation of a string database query language.
    Information Systems, 28, (2003), 311-337, link.

  • Hakli, R., Nykänen, M., and Tamm, H.
    Adding string processing capabilities to data management systems.
    Proc. Seventh Int. Symp. on String Processing and Information Retrieval (SPIRE 2000),
    IEEE Computer Society Press, Silver Spring, MD, 2000, 122-131, link.

  • Hakli, R., Nykänen, M., Tamm, H., and Ukkonen, E.
    Implementing a declarative string query language with string restructuring.
    Proc. First Int. Workshop on Practical Aspects of Declarative Languages (PADL'99),
    LNCS 1551, Springer, 1999, 179-195, link.

    My PhD thesis: "On minimality and size reduction of one-tape and multitape finite automata",
    University of Helsinki, 2004, link.