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On the size of transducers for bidirectional decoding of prefix codes

Laura Giambruno, Sabrina Mantaci (2012)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

In a previous paper [L. Giambruno and S. Mantaci, Theoret. Comput. Sci. 411 (2010) 1785–1792] a bideterministic transducer is defined for the bidirectional deciphering of words by the method introduced by Girod [IEEE Commun. Lett. 3 (1999) 245–247]. Such a method is defined using prefix codes. Moreover a coding method, inspired by the Girod’s one, is introduced, and a transducer that allows both right-to-left and left-to-right decoding by this method is defined. It is proved also that this transducer...

On the size of transducers for bidirectional decoding of prefix codes

Laura Giambruno, Sabrina Mantaci (2012)

RAIRO - Theoretical Informatics and Applications

In a previous paper [L. Giambruno and S. Mantaci, Theoret. Comput. Sci. 411 (2010) 1785–1792] a bideterministic transducer is defined for the bidirectional deciphering of words by the method introduced by Girod [IEEE Commun. Lett. 3 (1999) 245–247]. Such a method is defined using prefix codes. Moreover a coding method, inspired by the Girod’s one, is introduced, and a transducer that allows both right-to-left and left-to-right decoding by this...

On the size of transducers for bidirectional decoding of prefix codes

Laura Giambruno, Sabrina Mantaci (2012)

RAIRO - Theoretical Informatics and Applications

In a previous paper [L. Giambruno and S. Mantaci, Theoret. Comput. Sci. 411 (2010) 1785–1792] a bideterministic transducer is defined for the bidirectional deciphering of words by the method introduced by Girod [IEEE Commun. Lett. 3 (1999) 245–247]. Such a method is defined using prefix codes. Moreover a coding method, inspired by the Girod’s one, is introduced, and a transducer that allows both right-to-left and left-to-right decoding by this...

On the state complexity of semi-quantum finite automata

Shenggen Zheng, Jozef Gruska, Daowen Qiu (2014)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

Some of the most interesting and important results concerning quantum finite automata are those showing that they can recognize certain languages with (much) less resources than corresponding classical finite automata. This paper shows three results of such a type that are stronger in some sense than other ones because (a) they deal with models of quantum finite automata with very little quantumness (so-called semi-quantum one- and two-way finite automata); (b) differences, even comparing with probabilistic...

On the syntactic complexity of tree series

Symeon Bozapalidis, Antonios Kalampakas (2010)

RAIRO - Theoretical Informatics and Applications

We display a complexity notion based on the syntax of a tree series which yields two distinct hierarchies, one within the class of recognizable tree series and another one in the class of non-recognizable tree series.

On the topological complexity of infinitary rational relations

Olivier Finkel (2003)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

We prove in this paper that there exists some infinitary rational relations which are analytic but non Borel sets, giving an answer to a question of Simonnet [20].

On Varieties of Literally Idempotent Languages

Ondřej Klíma, Libor Polák (2008)

RAIRO - Theoretical Informatics and Applications

A language L ⊆A* is literally idempotent in case that ua2v ∈ L if and only if uav ∈ L, for each u,v ∈ A*, a ∈ A. Varieties of literally idempotent languages result naturally by taking all literally idempotent languages in a classical (positive) variety or by considering a certain closure operator on classes of languages. We initiate the systematic study of such varieties. Various classes of literally idempotent languages can be characterized using syntactic methods. A starting example is the...

On z -submonoids and z -codes

M. Madonia, S. Salemi, T. Sportelli (1991)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

One-Rule Length-Preserving Rewrite Systems and Rational Transductions

Michel Latteux, Yves Roos (2014)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

We address the problem to know whether the relation induced by a one-rule length-preserving rewrite system is rational. We partially answer to a conjecture of Éric Lilin who conjectured in 1991 that a one-rule length-preserving rewrite system is a rational transduction if and only if the left-hand side u and the right-hand side v of the rule of the system are not quasi-conjugate or are equal, that means if u and v are distinct, there do not exist words x, y and z such that u = xyz and v = zyx. We...

On-line finite automata for addition in some numeration systems

Christiane Frougny (2010)

RAIRO - Theoretical Informatics and Applications

We consider numeration systems where the base is a negative integer, or a complex number which is a root of a negative integer. We give parallel algorithms for addition in these numeration systems, from which we derive on-line algorithms realized by finite automata. A general construction relating addition in base β and addition in base βm is given. Results on addition in base β = b m , where b is a relative integer, follow. We also show that addition in base the golden ratio is computable by an on-line...

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