Results 211 to 220 of about 550 (233)
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J. Autom. Lang. Comb., 1999
We prove that every recursively enumerable language can be generated by a programmed grammar with context-free core rules using unconditional transfer with left-most derivation of type 3 or type 2. Interestingly, we have to give a non-constructive proof of the first mentioned universality result based on Higman's lemma, since finding a transformation ...
Henning Fernau, Frank Stephan 0001
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We prove that every recursively enumerable language can be generated by a programmed grammar with context-free core rules using unconditional transfer with left-most derivation of type 3 or type 2. Interestingly, we have to give a non-constructive proof of the first mentioned universality result based on Higman's lemma, since finding a transformation ...
Henning Fernau, Frank Stephan 0001
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Polynomial Generators of Recursively Enumerable Languages
2005For each language L, let $\hat{\mathcal F}_\cap(L)$ be the smallest intersection-closed full AFL generated by the language L. Furthermore, for each natural number k≥ 2 let $P_k=\{a^{n^k}|n\in\mathbb N\}$. By applying certain classical and recent results on Diophantine equations we show that $\mathcal L_{RE}=\hat{\mathcal F}_\cap(P_k)$, i.e., the family
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A characterization of recursively enumerable languages
Bull. EATCS, 1991It is shown that each recursively enumerable language \(L\) can be written in the form \(L=\text{red}(L_ 0)\cap V^*\), where red is the reduction operation considered in \textit{H. A. Maurer}, \textit{G. Rozenberg} and \textit{E. Welzl} [Inf. Control 54, 155-185 (1982; Zbl 0523.68065)], \(L_ 0\) is a linear language, and \(V\) is the alphabet of \(L\).
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On characterizing recursively enumerable languages by insertion grammars
Fundam. Informaticae, 2005Summary: Previously, it was proved that insertion grammars with weight at least 7 can characterize recursively enumerable languages (modulo a weak coding and an inverse morphism), and the question was formulated whether or not this result can be improved. In this paper, we come up with a positive answer to this question, by decreasing the weight of the
Madhu Mutyam +2 more
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Scattered context grammars generate any recursively enumerable language with two nonterminals
Information Processing Letters, 2010zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Erzsébet Csuhaj-Varjú, György Vaszil
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Turing Machines, Recursively Enumerable Languages and Type 0 Grammars
1993We have seen that a pushdown automaton can carry out computations which are beyond the capability of a finite automaton, which is perhaps the simplest sort of machine able to accept an infinite set of strings. At the other end of the scale of computational power is the Turing machine (after the English mathematician A. M.
Barbara H. Partee +2 more
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Representations of recursively enumerable array languages by contextual array grammars
Fundam. Informaticae, 2005Summary: The main result proved in this paper shows that the natural embedding of any recursively enumerable one-dimensional array language in the two-dimensional space can be characterized by the projection of a two-dimensional array language generated by a contextual array grammar working in the \(t\)-mode and with norm one.
Henning Fernau +2 more
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A unified approach to characterizations of recursively enumerable languages
Bull. EATCS, 1991Summary: Starting from an arbitrary phrase structure grammar \(G\) we construct two morphisms such that several well known representations of \(L(G)\) are obtained in a unified and easy way. These include characterizations in terms of the quotient operation [(*) \textit{V. Geffert}, Theor. Comput. Sci. 62, No.
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The 2003 Congress on Evolutionary Computation, 2003. CEC '03., 2004
We return to the no free lunch theorem, which is one of the most important theorems from the evolutionary computation foundations. We show that the no free lunch theorem can be interpreted as a trivial property of recursively enumerable languages. We demonstrate that if we consider not all problems and cost functions, i.e., a nontrivial property, the ...
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We return to the no free lunch theorem, which is one of the most important theorems from the evolutionary computation foundations. We show that the no free lunch theorem can be interpreted as a trivial property of recursively enumerable languages. We demonstrate that if we consider not all problems and cost functions, i.e., a nontrivial property, the ...
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Intuitionistic fuzzy recursive enumerable languages and recursive languages
AIP Conference Proceedings, 2019M. Rajasekar, V. Sumathi
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