Vesa Halava

76 papers A 1B 2C 5Journal 60Unranked 7
YearRankTypeTitle / Venue / Authors
2024 J jnl
Binary Generalized PCP for Two Periodic Morphisms is Decidable in Polynomial Time.
Int. J. Found. Comput. Sci.
Vesa Halava, Stepan Holub
2024 J jnl
Decision Problems on Copying and Shuffling.
Fundam. Informaticae
Vesa Halava, Tero Harju, Dirk Nowotka, Esa Sahla
2024 J jnl
On simulating Turing machines with matrix semigroups with integrality tests.
Theor. Comput. Sci.
Vesa Halava, Reino Niskanen
2024 J jnl
Preface.
Fundam. Informaticae
Vesa Halava, Jarkko Kari, Tero Laihonen
2023 J jnl
Decision Problems on Copying and Shuffling.
CoRR
Vesa Halava, Tero Harju, Dirk Nowotka, Esa Sahla
2023 J jnl
Integer Weighted Automata on Infinite Words.
Int. J. Found. Comput. Sci.
Vesa Halava, Tero Harju, Reino Niskanen, Igor Potapov
2023 J jnl
On bi-infinite and conjugate post correspondence problems.
RAIRO Theor. Informatics Appl.
Olivier Finkel, Vesa Halava, Tero Harju, Esa Sahla
2022 J jnl
A recursive function coding number theoretic functions.
CoRR
Vesa Halava, Tero Harju, Teemu Pirttimäki
2021 C conf
Integer Weighted Automata on Infinite Words.
DLT
Vesa Halava, Tero Harju, Reino Niskanen, Igor Potapov
2021 J jnl
The Conjugate Post Correspondence Problem.
CoRR
Vesa Halava, Tero Harju, Esa Sahla
2021 J jnl
Undecidability in Finite Transducers, Defense Systems and Finite Substitutions.
CoRR
Vesa Halava
2020 J jnl
On Shuffling a Word with its Letter-to-Letter Substitution.
Fundam. Informaticae
Vesa Halava, Tero Harju, Esa Sahla
2020 J jnl
On the Steps of Emil Post: from Normal Systems to the Correspondence Decision Problem.
Acta Cybern.
Vesa Halava, Tero Harju
2018 J jnl
On fixed points of rational transductions.
Theor. Comput. Sci.
Vesa Halava, Tero Harju, Esa Sahla
2018 J jnl
Perface.
Fundam. Informaticae
Vesa Halava, Juhani Karhumäki, Yuri V. Matiyasevich, Mikhail V. Volkov
2017 J jnl
A New Proof for Undecidability of the Bi-Infinite Post Correspondence Problem.
Fundam. Informaticae
Vesa Halava, Tero Harju, Esa Sahla
2017 J jnl
Small Semi-Thue System Universal with Respect to the Termination Problem.
Fundam. Informaticae
Vesa Halava, Yuri V. Matiyasevich, Reino Niskanen
2017 J jnl
Walks on tilings of polygons.
Theor. Comput. Sci.
Vesa Halava, Tero Harju
2017 J jnl
Weighted automata on infinite words in the context of Attacker-Defender games.
Inf. Comput.
Vesa Halava, Tero Harju, Reino Niskanen, Igor Potapov
2015 C conf
On Robot Games of Degree Two.
LATA
Vesa Halava, Reino Niskanen, Igor Potapov
2015 J jnl
On the n-permutation Post Correspondence Problem.
Theor. Comput. Sci.
Mari Ernvall, Vesa Halava, Tero Harju
2015 C conf
Weighted Automata on Infinite Words in the Context of Attacker-Defender Games.
CiE
Vesa Halava, Tero Harju, Reino Niskanen, Igor Potapov
2014 J jnl
Another proof of undecidability for the correspondence decision problem - Had I been Emil Post.
CoRR
Vesa Halava
2014 J jnl
On Undecidability of Counter Reachability Games in Dimension One.
CoRR
Vesa Halava, Reino Niskanen, Igor Potapov
2014 J jnl
Preface.
Fundam. Informaticae
Vesa Halava, Juhani Karhumäki, Yuri V. Matiyasevich
2014 J jnl
Tighter Undecidability Bounds for Matrix Mortality, Zero-in-the-Corner Problems, and More.
CoRR
Julien Cassaigne, Vesa Halava, Tero Harju, François Nicolas
2013 J jnl
Decision Problems for Probabilistic Finite Automata on Bounded Languages.
Fundam. Informaticae
Paul C. Bell, Vesa Halava, Mika Hirvensalo
2013 — conf
Deterministic Semi-Thue Systems and Variants of Post Correspondence Problem.
WORDS
Vesa Halava
2013 J jnl
New proof for the undecidability of the circular PCP.
Acta Informatica
Vesa Halava, Tero Harju
2012 J jnl
Words, Graphs, Automata, and Languages; Special Issue Honoring the 60th Birthday of Professor Tero Harju.
Fundam. Informaticae
Vesa Halava, Juhani Karhumäki, Dirk Nowotka, Grzegorz Rozenberg
2011 — conf
A new proof for the decidability of D0L ultimate periodicity
WORDS
Vesa Halava, Tero Harju, Tomi Kärki
2011 J jnl
Reduction Tree of the Binary Generalized Post Correspondence Problem.
Int. J. Found. Comput. Sci.
Vesa Halava, Stepan Holub
2010 — conf
On the Joint Spectral Radius for Bounded Matrix Languages.
RP
Paul Bell, Vesa Halava, Mika Hirvensalo
2010 C conf
On the Periodicity of Morphic Words.
Developments in Language Theory
Vesa Halava, Tero Harju, Tomi Kärki, Michel Rigo
2010 J jnl
On the number of squares in partial words.
RAIRO Theor. Informatics Appl.
Vesa Halava, Tero Harju, Tomi Kärki
2009 J jnl
On post correspondence problem for letter monotonic languages.
Theor. Comput. Sci.
Vesa Halava, Jarkko Kari, Yuri V. Matiyasevich
2009 J jnl
Overlap-freeness in infinite partial words.
Theor. Comput. Sci.
Vesa Halava, Tero Harju, Tomi Kärki, Patrice Séébold
2009 J jnl
Preface.
Int. J. Found. Comput. Sci.
Vesa Halava, Igor Potapov
2009 J jnl
The theorem of Fine and Wilf for relational periods.
RAIRO Theor. Informatics Appl.
Vesa Halava, Tero Harju, Tomi Kärki
2008 J jnl
Interaction Properties of Relational Periods.
Discret. Math. Theor. Comput. Sci.
Tomi Kärki, Tero Harju, Vesa Halava
2008 J jnl
Matrix Equations and Hilbert's Tenth Problem.
Int. J. Algebra Comput.
Paul Bell, Vesa Halava, Tero Harju, Juhani Karhumäki, Igor Potapov
2008 J jnl
Post Correspondence Problem for short words.
Inf. Process. Lett.
Vesa Halava, Tero Harju, Mika Hirvensalo, Juhani Karhumäki
2008 — conf
Preface.
RP
Vesa Halava, Igor Potapov
2008 J jnl
Preface.
Int. J. Found. Comput. Sci.
Vesa Halava, Igor Potapov
2008 — ed.
Proceedings of the Second Workshop on Reachability Problems in Computational Models, RP 2008, Liverpool, UK, September 15-17, 2008
RP
Vesa Halava, Igor Potapov
2008 J jnl
Square-free partial words.
Inf. Process. Lett.
Vesa Halava, Tero Harju, Tomi Kärki
2007 J jnl
Extension of the decidability of the marked PCP to instances with unique blocks.
Theor. Comput. Sci.
Vesa Halava, Tero Harju, Juhani Karhumäki, Michel Latteux
2007 J jnl
Improved matrix pair undecidability results.
Acta Informatica
Vesa Halava, Mika Hirvensalo
2007 J jnl
Relational codes of words.
Theor. Comput. Sci.
Vesa Halava, Tero Harju, Tomi Kärki
2007 J jnl
The Structure of Infinite Solutions of Marked and Binary Post Correspondence Problems.
Theory Comput. Syst.
Vesa Halava, Tero Harju, Juhani Karhumäki
2007 J jnl
Undecidability Bounds for Integer Matrices Using Claus Instances.
Int. J. Found. Comput. Sci.
Vesa Halava, Tero Harju, Mika Hirvensalo
2006 J jnl
Positivity of second order linear recurrent sequences.
Discret. Appl. Math.
Vesa Halava, Tero Harju, Mika Hirvensalo
2006 J jnl
Undecidability in omega-Regular Languages.
Fundam. Informaticae
Vesa Halava, Tero Harju, Juhani Karhumäki
2006 J jnl
Undecidability of infinite post correspondence problem for instances of Size 9.
RAIRO Theor. Informatics Appl.
Vesa Halava, Tero Harju
2005 J jnl
Equality sets for recursively enumerable languages.
RAIRO Theor. Informatics Appl.
Vesa Halava, Tero Harju, Hendrik Jan Hoogeboom, Michel Latteux
2005 J jnl
Equality sets of prefix morphisms and regular star languages.
Inf. Process. Lett.
Vesa Halava, Tero Harju, Michel Latteux
2005 J jnl
Representation of Regular Languages by Equality Sets.
Bull. EATCS
Vesa Halava, Tero Harju, Michel Latteux
2004 — conf
Integer Weighted Finite Automata, Matrices, and Formal Power Series over Laurent Polynomials.
Theory Is Forever
Vesa Halava
2004 J jnl
Undecidability in matrices over Laurent polynomials.
Adv. Appl. Math.
Vesa Halava, Tero Harju
2004 J jnl
Valence Languages Generated by Equality Sets.
J. Autom. Lang. Comb.
Vesa Halava, Tero Harju, Hendrik Jan Hoogeboom, Michel Latteux
2003 J jnl
Decidability of the binary infinite Post Correspondence Problem.
Discret. Appl. Math.
Vesa Halava, Tero Harju, Juhani Karhumäki
2003 B conf
Languages Defined by Generalized Equality Sets.
FCT
Vesa Halava, Tero Harju, Hendrik Jan Hoogeboom, Michel Latteux
2002 J jnl
Binary (generalized) Post Correspondence Problem.
Theor. Comput. Sci.
Vesa Halava, Tero Harju, Mika Hirvensalo
2002 — conf
Infinite Solutions of Marked Post Correspondence Problem.
Formal and Natural Computing
Vesa Halava, Tero Harju
2001 C conf
An Undecidability Result Concerning Periodic Morphisms.
Developments in Language Theory
Vesa Halava, Tero Harju
2001 J jnl
Marked PCP is decidable.
Theor. Comput. Sci.
Vesa Halava, Mika Hirvensalo, Ronald de Wolf
2001 J jnl
Mortality in Matrix Semigroups.
Am. Math. Mon.
Vesa Halava, Tero Harju
2001 J jnl
Some New Results on Post Correspondence Problem and Its Modifications.
Bull. EATCS
Vesa Halava, Tero Harju
2000 J jnl
Generalized Post Correspondence Problem for Marked Morphisms.
Int. J. Algebra Comput.
Vesa Halava, Tero Harju, Mika Hirvensalo
2000 J jnl
Periods and Binary Words.
J. Comb. Theory A
Vesa Halava, Tero Harju, Lucian Ilie
1999 A conf
Decidability and Undecidability of Marked PCP.
STACS
Vesa Halava, Mika Hirvensalo, Ronald de Wolf
1999 B conf
Generalized PCP Is Decidable for Marked Morphisms.
FCT
Vesa Halava, Tero Harju, Mika Hirvensalo
1999 — conf
Languages Accepted by Integer Weighted Finite Automata.
Jewels are Forever
Vesa Halava, Tero Harju
1999 J jnl
Undecidability in Integer Weighted Finite Automata.
Fundam. Informaticae
Vesa Halava, Tero Harju
1999 J jnl
Undecidability of the equivalence of finite substitutions on regular language.
RAIRO Theor. Informatics Appl.
Vesa Halava, Tero Harju
1997 J jnl
On a Geometric Problem of Zigzags.
Inf. Process. Lett.
Vesa Halava, Tero Harju, Lucian Ilie