Showing papers on "Chomsky hierarchy published in 1989"
01 Jan 1989
TL;DR: For a long time, the word ‘quantifier’ in linguistics and philosophy simply stood for the universal and existential quantifiers of standard predicate logic, but the dominance of predicate logic has obscured the fact that the quantifier expressions form a syntactic category, with characteristic interpretations, and with many more members than ∀ and ∃.
Abstract: For a long time, the word ‘quantifier’ in linguistics and philosophy simply stood for the universal and existential quantifiers of standard predicate logic. In fact, this use is still prevalent in elementary textbooks. It seems fair to say that the dominance of predicate logic in these fields has obscured the fact that the quantifier expressions form a syntactic category, with characteristic interpretations, and with many more members than ∀ and ∃.
206 citations
Book•
01 Jan 1989
TL;DR: In this paper, the problem of semantics after Chomsky, Norbert Hornstein logical form and linguistic theory, Jaako Hintikka types and tokens in linguistics, Sylvian Bromberger how not to become so confused about linguistics and Alexander George when is a grammar psychologically real.
Abstract: Why should the mind be modular?, Jerry A. Fodor meaning and the mental - the problem of semantics after Chomsky, Norbert Hornstein logical form and linguistic theory, Jaako Hintikka types and tokens in linguistics, Sylvian Bromberger how not to become so confused about linguistics, Alexander George when is a grammar psychologically real?, Christopher Peacocke tacit knowledge and subdoxastic states, Martin Davies knowledge of reference, James Higginbotham wherein is language social?, Tyler Burge language and communication, Michael Dummett model theory and the "Factuality of Semantics", Hilary Putnam Wittgenstein's rule-following considerations and the central project of theoretical linguistics, Crispin Wright.
75 citations
Book•
01 Jan 1989
TL;DR: In this article, Sunitha and Kalyani present a formal language and automata theory for regular expressions and finite automata, which is free to download, and also includes solution sets.
Abstract: Guyz, i need dis book. I downloaded from google books but some pages are not available so. I ll b thankful to one who ll help.a formal grammar and it is more capable than a finite-state machine but. 2K.V.N Sunitha,N Kalyani Formal Languages and automata theoryTata. Formal Languages and Automata Theory. Regular Expressions and Finite Automata. Best of all, its free to download, and also includes solution sets.
44 citations
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TL;DR: A new class of grammars with derivation restrictions (similar to the matrix, conditional ones, etc.) is presented, where if a rule of a subset peculiar to P is used in a derivation then it is compulsory to use only productions of that particular subset as long as it is possible.
Abstract: In this article a new class of grammars with derivation restrictions (similar to the matrix, conditional ones, etc.) is presented. In this situation, if a rule of a subset peculiar to P is used in a derivation then it is compulsory to use only productions of that particular subset as long as it is possible. According to the Chomsky hierarchy, naturally attributed to the grammars the generative power of the modular grammars is studied (Section 2), a series of results being obtained as well as a normal form similar to Chomsky's normal one. The following two paragraphs deal with the closure properties—only for ℳ 2 and (proving that ℳ 2 is AFL) and also with decision problems connected with the modular grammars, using algorithmical proofs in general.
19 citations
TL;DR: A syntactic model for generating sets of images, where an image can be viewed as an array over finite alphabet is defined, called image grammar, which can be considered as a generalization of classical Chomsky grammar.
Abstract: We define a syntactic model for generating sets of images, where an image can be viewed as an array over finite alphabet. This model is called image grammar. Image grammar can be considered as a generalization of classical Chomsky grammar. Then we study some combinatorial and language theoretical properties such as reduction, pumping lemmas, complexity measure, we give a strict infinite hierarchy. We also characterize these families in terms of deterministic substitutions and Chomsky languages.
16 citations
12 Jul 1989
TL;DR: It is shown that the set of all the unifiers of two atoms is finite and computable by restricting the form of axioms and goals without losing generality.
Abstract: In this paper, we give a theoretical foundation of EFS (elementary formal system) as a logic programming language We show that the set of all the unifiers of two atoms is finite and computable by restricting the form of axioms and goals without losing generality The restriction makes the negation as failure rule complete We give two conditions of EFS's such that the negation as failure rule is identical to the closed world assumption We also give a subclass of EFS's where a procedure of CWA is given as bounding the length of derivations We compare these classes with the Chomsky hierarchy
11 citations
7 citations
TL;DR: This article propose a series of generalizations of Langford strings considered in Combinatorics and discuss the place of corresponding languages in Chomsky hierarchy, as well as their contextual ambiguity in the sense of algebraic linguistics.
Abstract: We propose a series of generalizations of Langford strings considered in Combinatorics and discuss the place of the corresponding languages in Chomsky hierarchy, as well as their contextual ambiguity in the sense of algebraic linguistics.
6 citations
Journal Article•
6 citations
11 Jul 1989
TL;DR: This paper introduced Kolmogorov complexity as a new technique in formal language theory for the separation of deterministic contextfree languages and contextfree regular languages, and showed that k + 1 heads are better than k heads.
Abstract: We introduce Kolmogorov complexity as a new technique in Formal Language Theory We give an alternative for pumping lemma(s) and a new characterization for regular languages For the separation of deterministic contextfree languages and contextfree languages no pumping lemmas or any other general method was known We give a first general technique to separate these classes, and illustrate its use on four examples previously requiring labourous ad hoc methods The approach is also successful at the high end of the Chomsky hierarchy since one can quantify nonrecursiveness in terms of Kolmogorov complexity We also give a new proof, using Kolmogorov complexity, of Yao and Rivest's result that k + 1 heads are better than k heads
5 citations
01 Jan 1989
TL;DR: This work presents a new approach to formal language theory using Kolmogorov complexity, an alternative for pumping lemma(s), a new characterization for regular languages, and a new method to separate deterministic context-free languages and nondeterministic context -free languages.
Abstract: We present a new approach to formal language theory using Kolmogorov complexity. The main results presented here are an alternative for pumping lemma(s), a new characterization for regular languages, and a new method to separate deterministic context-free languages and nondeterministic context-free languages. The use of the new "incompressibility arguments" is illustrated by many examples. The approach is also successful at the high end of the Chomsky hierarchy since one can quantify nonrecursiveness in terms of Kolmogorov complexity.
TL;DR: This paper proves a pumping result for k-context-free languages and shows that the families of k-languages form a strict hierarchy with respect to k, and results showing the strictness of the hierarchy are presented.
Abstract: Languages generated by context-free grammars by rewriting always exactly k nonterminals simultaneouslyk ≥ 1, are called k-context-free languages. We prove a pumping result for k-context-free languages and using it show that the families of k-languages form a strict hierarchy with respect to k. The paper is divided into two parts. The main results showing the strictness of the hierarchy of k-languages are presented in Part 2. This first part contains definitions and preliminary results on derivation forests and k-schedules.
TL;DR: In this article, it was shown that for every regular language L, the full permutation of the letters of the words in L yields a regular language, and a special family of bounded languages, called bounded regular languages, were shown to be closed under cyclic permutations on words.
Abstract: The language classes of the Chomsky hierarchy are known (Ruohonen [6]) to be closed under cyclic permutations on words. For an alphabet Σ, we give a description of the ideals in Σ* that are closed under cyclic permutation of letters in words. Given a regular language L in Σ*, we give two different constructions of automata accepting the language obtained by cyclically permuting the letters of words in L. Finally, we discuss a special family of bounded languages in which, for every regular language L, the full permutation of the letters of the words in L yields a regular language.