Publications

Articles

1. J.C. Costa. Free profinite R-trivial, locally idempotent and locally commutative semigroups

Semigroup Forum 58 (1999), 423-444.

2. J.C. Costa. Free profinite semigroups over some classes of semigroups locally in DG

International Journal of Algebra and Computation 10 (2000), 491-537.

3. J.C. Costa. Some variations on the notion of locally testable language

in Proceedings of the International Conference on Semigroups,

eds. P. Smith, E. Giraldes, P. Martins, World Scientific, 2000, pp. 54-68.

4. J.C. Costa. Free profinite locally idempotent and locally commutative semigroups

Journal of Pure and Applied Algebra 163 (2001), 19-47.

5. J.C. Costa. Some pseudovariety joins involving locally trivial semigroups

Semigroup Forum 64 (2002), 12-28.

6. J.C. Costa. Some pseudovariety joins involving groups and locally trivial semigroups

in Semigroups, Algorithms, Automata and Languages (Coimbra, Portugal, 2001),

eds. G. Gomes, J.-E. Pin, P. Silva, World Scientific, 2002, pp. 341-348.

7. J.C. Costa. Biinfinite words with maximal recurrent unbordered factors

Theoretical Computer Science 290 (2003), 2053-2061.

[pdf file of pre-print].

1. J.C. Costa, M.L. Teixeira. Tameness of the pseudovariety LSl

International Journal of Algebra and Computation 14 (2004) 627-654.

[pdf file of pre-print].

2. J.C. Costa. Reducibility of joins involving some locally trivial pseudovarieties

Communications in Algebra 32 (2004) 3517-3535.

[pdf file of pre-print].

3. J. Almeida, J.C. Costa, M. Zeitoun. Tameness of pseudovariety joins involving R

Monatshefte für Mathematik 146 (2005) 89-111.

[pdf file of post-print].

4. J. Almeida, J.C. Costa, M. Zeitoun. Complete reducibility of pseudovarieties

in Proceedings of the Conference on Semigroups and Formal Languages (Lisbon,July, 2005),

eds. J. André, M. Branco, V.H. Fernandes, J. Fountain, G. Gomes, J. Meakin, World Scientific, 2007, pp. 9-25.

[pdf file of post-print].

5. J. Almeida, J.C. Costa, M. Zeitoun. Complete reducibility of systems of equations with respect to R

Portugaliae Mathematica 64 (2007), 445-508.

[pdf file of pre-print].

6. J. Almeida, J.C. Costa and M. Zeitoun. Pointlike sets with respect to R and J

Journal of Pure and Applied Algebra 212 (2008), 486-499.

[pdf file of post-print].

7. J.C. Costa, C. Nogueira. On bases of identities for the ω-variety generated by locally testable semigroups

Theoretical Computer Science 401 (2008), 206-216.

[pdf file of post-print].

8. J. Almeida, J.C. Costa, M. Zeitoun. ω-terms over finite aperiodic semigroups

in Proceedings of the International Conference ROGICS'08,

eds. Y. Boudabbous, N. Zaguia, Nouha Editions, Sfax, Tunisia, 2008, pp. 364-371.

[pdf file of post-print].

9. J.C. Costa, C. Nogueira. Complete reducibility of the pseudovariety LSl

International Journal of Algebra and Computation 19 (2009), 247–282.

[pdf file of post-print].

10. J. Almeida, J.C. Costa and M. Zeitoun. Iterated periodicity over finite aperiodic semigroups

[pdf file of pre-print].

11. J. Almeida, J.C. Costa and M. Zeitoun. Some structural properties of the free profinite aperiodic semigroup

[pdf file of pre-print].

12. J. Almeida, J.C. Costa, M.L. Teixeira. Semidirect product with an order-computable pseudovariety and tameness

Semigroup Forum 81 (2010) 26–50.

[pdf file of pre-print].

13. J.C. Costa, C. Nogueira. Tameness of joins involving the pseudovariety of local semilattices

[pdf file of pre-print].

Dissertations

I. Pseudovariedades da forma VW

Synthesis work submitted to the “Provas de Aptidão Pedagógica e Capacidade Científica”,

University of Minho, 1993.

Committee: Assis Azevedo (supervisor), Pedro Silva

II. Quelques intersections de variétés de semigroupes finis et de variétés de langages, opérations implicites

Ph.D. Thesis, University of Paris 6, 1998.

(pdf file).

Committee: Assis Azevedo, Philippe Chrétienne, Jean-Eric Pin, Mikhail Volkov, Pascal Weil (supervisor),

Marc Zeitoun