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Efficient validation and construction of border arrays and validation of string matching automata

Jean-Pierre Duval, Thierry Lecroq, Arnaud Lefebvre (2009)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

We present an on-line linear time and space algorithm to check if an integer array f is the border array of at least one string w built on a bounded or unbounded size alphabet Σ . First of all, we show a bijection between the border array of a string w and the skeleton of the DFA recognizing Σ * w , called a string matching automaton (SMA). Different strings can have the same border array but the originality of the presented method is that the correspondence between a border array and a skeleton of SMA...

Efficient validation and construction of border arrays and validation of string matching automata

Jean-Pierre Duval, Thierry Lecroq, Arnaud Lefebvre (2008)

RAIRO - Theoretical Informatics and Applications

We present an on-line linear time and space algorithm to check if an integer array f is the border array of at least one string w built on a bounded or unbounded size alphabet Σ. First of all, we show a bijection between the border array of a string w and the skeleton of the DFA recognizing Σ*ω, called a string matching automaton (SMA). Different strings can have the same border array but the originality of the presented method is that the correspondence between a border array and a...

Efficient weighted expressions conversion

Faissal Ouardi, Djelloul Ziadi (2008)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

J. Hromkovic et al. have given an elegant method to convert a regular expression of size n into an ε -free nondeterministic finite automaton having O ( n ) states and O ( n log 2 ( n ) ) transitions. This method has been implemented efficiently in O ( n log 2 ( n ) ) time by C. Hagenah and A. Muscholl. In this paper we extend this method to weighted regular expressions and we show that it can be achieved in O ( n log 2 ( n ) ) time.

Efficient weighted expressions conversion

Faissal Ouardi, Djelloul Ziadi (2007)

RAIRO - Theoretical Informatics and Applications

J. Hromkovic et al. have given an elegant method to convert a regular expression of size n into an ε-free nondeterministic finite automaton having O(n) states and O(nlog2(n)) transitions. This method has been implemented efficiently in O(nlog2(n)) time by C. Hagenah and A. Muscholl. In this paper we extend this method to weighted regular expressions and we show that it can be achieved in O(nlog2(n)) time.

Egipsys: An enhanced gene expression programming approach for symbolic regression problems

Heitor Lopes, Wagner Weinert (2004)

International Journal of Applied Mathematics and Computer Science

This paper reports a system based on the recently proposed evolutionary paradigm of gene expression programming (GEP). This enhanced system, called EGIPSYS, has features specially suited to deal with symbolic regression problems. Amongst the new features implemented in EGIPSYS are: new selection methods, chromosomes of variable length, a new approach to manipulating constants, new genetic operators and an adaptable fitness function. All the proposed improvements were tested separately, and proved...

Elastic wave propagation in parallel: the Huygens' approach.

Javier Sabadell (2002)

Revista Matemática Complutense

The use of parallel computers makes it feasible to simulate elastic waves throughout large heterogeneous structures, and new domain decomposition methods can be used to increase their efficiency and decrease the computing time spent in the simulation. In this paper we introduce a simple parallel algorithm for the propagation of elastic waves in complex heterogeneous media after a finite element discretization. This method performs more efficiently than classic domain decomposition techniques based...

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