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Strategies to scan pictures with automata based on Wang tiles

Violetta Lonati, Matteo Pradella (2011)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

Wang automata are devices for picture language recognition recently introduced by us, which characterize the class REC of recognizable picture languages. Thus, Wang automata are equivalent to tiling systems or online tessellation acceptors, and are based like Wang systems on labeled Wang tiles. The present work focus on scanning strategies, to prove that the ones Wang automata are based on are those following four kinds of movements: boustrophedonic, “L-like”, “U-like”, and spirals.

Strategies to scan pictures with automata based on Wang tiles

Violetta Lonati, Matteo Pradella (2011)

RAIRO - Theoretical Informatics and Applications

Wang automata are devices for picture language recognition recently introduced by us, which characterize the class REC of recognizable picture languages. Thus, Wang automata are equivalent to tiling systems or online tessellation acceptors, and are based like Wang systems on labeled Wang tiles. The present work focus on scanning strategies, to prove that the ones Wang automata are based on are those following four kinds of movements: boustrophedonic, “L-like”, “U-like”, and spirals.

String distances and intrusion detection: Bridging the gap between formal languages and computer security

Danilo Bruschi, Giovanni Pighizzini (2006)

RAIRO - Theoretical Informatics and Applications

In this paper we analyze some intrusion detection strategies proposed in the literature and we show that they represent the various facets of a well known formal languages problem: computing the distance between a string x and a language L. In particular, the main differences among the various approaches adopted for building intrusion detection systems can be reduced to the characteristics of the language L and to the notion of distance adopted. As a further contribution we will also show that from...

Strongly locally testable semigroups with commuting idempotents and related languages

Carla Selmi (2010)

RAIRO - Theoretical Informatics and Applications

If we consider words over the alphabet which is the set of all elements of a semigroup S, then such a word determines an element of S: the product of the letters of the word. S is strongly locally testable if whenever two words over the alphabet S have the same factors of a fixed length k, then the products of the letters of these words are equal. We had previously proved [19] that the syntactic semigroup of a rational language L is strongly locally testable if and only if L is both locally...

Study of irreducible balanced pairs for substitutive languages

Julien Bernat (2008)

RAIRO - Theoretical Informatics and Applications

Let ℒ be a language. A balanced pair (u,v) consists of two words u and v in ℒ which have the same number of occurrences of each letter. It is irreducible if the pairs of strict prefixes of u and v of the same length do not form balanced pairs. In this article, we are interested in computing the set of irreducible balanced pairs on several cases of languages. We make connections with the balanced pairs algorithm and discrete geometrical constructions related to substitutive languages. We characterize...

Substitutions, abstract number systems and the space filling property

Clemens Fuchs, Robert Tijdeman (2006)

Annales de l’institut Fourier

In this paper we study multi-dimensional words generated by fixed points of substitutions by projecting the integer points on the corresponding broken halfline. We show for a large class of substitutions that the resulting word is the restriction of a linear function modulo 1 and that it can be decided whether the resulting word is space filling or not. The proof uses lattices and the abstract number system associated with the substitution.

Superiority of one-way and realtime quantum machines∗∗∗

Abuzer Yakaryılmaz (2012)

RAIRO - Theoretical Informatics and Applications

In automata theory, quantum computation has been widely examined for finite state machines, known as quantum finite automata (QFAs), and less attention has been given to QFAs augmented with counters or stacks. In this paper, we focus on such generalizations of QFAs where the input head operates in one-way or realtime mode, and present some new results regarding their superiority over their classical counterparts. Our first result is about the nondeterministic...

Superiority of one-way and realtime quantum machines

Abuzer Yakaryılmaz (2012)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

In automata theory, quantum computation has been widely examined for finite state machines, known as quantum finite automata (QFAs), and less attention has been given to QFAs augmented with counters or stacks. In this paper, we focus on such generalizations of QFAs where the input head operates in one-way or realtime mode, and present some new results regarding their superiority over their classical counterparts. Our first result is about the nondeterministic acceptance mode: Each quantum model...

Superiority of one-way and realtime quantum machines∗∗∗

Abuzer Yakaryılmaz (2012)

RAIRO - Theoretical Informatics and Applications

In automata theory, quantum computation has been widely examined for finite state machines, known as quantum finite automata (QFAs), and less attention has been given to QFAs augmented with counters or stacks. In this paper, we focus on such generalizations of QFAs where the input head operates in one-way or realtime mode, and present some new results regarding their superiority over their classical counterparts. Our first result is about the nondeterministic...

Sur la complexité de mots infinis engendrés par des q -automates dénombrables

Marion Le Gonidec (2006)

Annales de l’institut Fourier

On étudie, dans cet article, les propriétés combinatoires de mots engendrés à l’aide de q -automates déterministes dénombrables de degré borné, ou de manière équivalente, engendrés par des substitutions de longueur constante uniformément bornées sur un alphabet dénombrable. En particulier, on montre que la complexité de tels mots est au plus polynomiale et que, sur plusieurs exemples, elle est au plus de l’ordre de grandeur de n ( log n ) p .

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