Wyniki wyszukiwania - Biblioteka Nauki

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

3 Fundamenta Informaticae

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: rewrite system

Sortuj według:

Ogranicz wyniki do:

Algorithms and reductions for rewriting problems

100%

Verma R. M. , Rusinowitch M. , Lugiez D.

Fundamenta Informaticae

2001

tom Vol. 46, nr 3

257-276

In this paper we initiate a study of polynomial-time reductions for some basic decision problems of rewrite systems. We then give a polynomial-time algorithm for the unique-normal-form property of ground systems for the first time. Next we prove undecidability of several problems for a fixed string rewriting system using our reductions. Finally, we prove the decidability of confluence for commutative semi-thue systems. The Confluence and Unique-normal-form property are shown Expspace-hard for commutative semi-thue systems. We also show that there is a family of string rewrite systems for which the word problem is trivially decidable but confluence is undecidable, and we show a linear equational theory with decidable word problem but undecidable linear equational matching problem.

The ground tree transducer game with identical tree automata

80%

Apro J. , Vagvölgyi S.

Fundamenta Informaticae

2001

tom Vol. 45, nr 3

157-172

We study that version of the ground tree transducer game where the same tree automaton appears as the first and second component of the associated ground tree transducer. We give conditions which imply that Beta has a winning strategy. Furthermore, we show the following decidability result. Given a ground tree transducer game where the underlying tree automaton A cannot evaluate some tree into a state or A is deterministic, we can decide which player has a winning strategy. Moreover, whatever player has a winning strategy, we can effectively construct a partial recursive winning strategy for him.

H-trees: a Model of Evolutionary Scenarios with Horizontal Gene Transfer

60%

Górecki P.

Fundamenta Informaticae

2010

tom Vol. 103, nr 1-4

105-128

In this paper, we present a model of evolution of genes in the context of evolution of species. The concept is based on reconciliation models. We assume that the gene evolution is modeled by macro-evolutionary events like gene duplications, losses and horizontal gene transfers (HGTs) while the evolution of species is shaped by speciation events. We define an evolutionary scenario (called an H-tree) which will represent the common evolution of genes and species. We propose a rewrite system for transforming the scenarios. We prove that the system is confluent, sound and strongly normalizing. We show that a scenario in a normal form (that is, non-reducible) is unique and minimal in the sense of the cost computed as the total number of gene duplications, losses and HGTs (mutation cost). We present a classification of the scenarios and analyze their hierarchies.