Showing papers on "Rule-based machine translation published in 1976"
TL;DR: A condition for an attribute grammar is given which assures that the semantics of any program can be evaluated in a single pass over the derivation tree, and an algorithm is discussed which decides how many passes from left to right are in general necessary, given the attribute grammar.
Abstract: This paper describes attribute grammars and their use for the definition of programming languages and compilers; a formal definition of attribute grammars and a discussion of some of its important aspects are included. The paper concentrates on the evaluation of semantic attributes in a few passes from left to right over the derivation tree of a program. A condition for an attribute grammar is given which assures that the semantics of any program can be evaluated in a single pass over the derivation tree, and an algorithm is discussed which decides how many passes from left to right are in general necessary, given the attribute grammar. These notions are explained in terms of an example grammar which describes the scope rules of Algol 60. Practical questions, such as the relative efficiency of different evaluation schemes, and the ease of adapting the attribute grammar of a given programming language to the left-to-right evaluation scheme are discussed.
203 citations
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01 Jan 1976
TL;DR: Work has shifted from research in the areas of phonetic recognition and linguistic processing to integration of an experimental speech understanding system and a first version of an acoustic phonetic 'front end' has been developed and tested with a corpus of 73 sentences.
Abstract: : Work has shifted from research in the areas of phonetic recognition and linguistic processing to integration of an experimental speech understanding system. This mid-term system, scheduled for completion in April 1974, will be composed of phonetic recognition, linguistic processing, and functional response modules. The system task is the vocal command of a data retrieval, analysis, and display facility intended to support a researcher in studying the acoustic correlates of phonemic events. A first version of an acoustic phonetic 'front end' has been developed and tested with a corpus of 73 sentences. It has been operated in the system environemnt with two different linguistic processing modules, and encoraging results have been achieved in preliminary testing. The tests involved vocabularies of 200 to 500 words and context-free grammars of 111 to 300 production statements.
68 citations
TL;DR: A cost function is developed, based on information-theoretic concepts, that measures the complexity of a stochastic context-free grammar, as well as the discrepancy between its language and a given stoChastic language sample.
54 citations
01 Feb 1976
TL;DR: An algorithm for automatic recognition of handwritten capital letters is described in terms of formal grammars, and the syntactic recognition scheme is extended by introducing the concept of fuzzy sets instead of the usual probabilistic approach.
Abstract: An algorithm for automatic recognition of handwritten capital letters is described in terms of formal grammars. The formalism is used for a priori computer time and memory optimization. Moreover, the syntactic recognition scheme is extended by introducing the concept of fuzzy sets instead of the usual probabilistic approach.
50 citations
01 Jan 1976
TL;DR: This chapter provides an overview, illustrated by a great number of examples, of the syntactic (linguistic) pattern recognition of one-dimensional and high-dimensional grammars.
Abstract: This chapter provides an overview, illustrated by a great number of examples, of the syntactic (linguistic) pattern recognition Languages are used to describe patterns, and syntax analysis procedures are employed as recognition procedures Methods for the selection of pattern primitives are presented Both one-dimensional (string) and high-dimensional grammars are discussed and their applications to one-dimensional and high-dimensional patterns demonstrated Problems for further research are suggested
26 citations
TL;DR: A direct algebraic treatment of context-free languages by means of the recently-developed theory of hetrogeneous algebras shows that many of the classic notions for context- free grammars have highly suggestive algebraic equivalents, and that the algebraic Treatment suggests new, fruitful notions.
Abstract: Virtually all algebraic approaches to formal language theory involve an intervening notion of machine, and it is the machine theory which is treated algebraically. The present article details a direct algebraic treatment of context-free languages by means of the recently-developed theory of hetrogeneous algebras. It is seen that many of the classic notions for context-free grammars have highly suggestive algebraic equivalents, and, further, that the algebraic treatment suggests new, fruitful notions.
17 citations
TL;DR: In the context independent L systems with varlsus generalizations of context free grammars, the class of ETOL systems (see [S ] ) fGgnls is perhaps the central cl;dss among various classes of context indepenGent L systems.
7 citations
20 Oct 1976
TL;DR: A new type of grammar for generating two-dimensional patterns is introduced and several unrelated properties of the classes of patterns generated by various varieties of matrix grammars are announced.
Abstract: A new type of grammar for generating two-dimensional patterns is introduced. The generation of a pattern occurs in two phases. First, a string grammar generates a “row” of syntactic variables (the sequential phase). Then a battery of instances of string grammars—one for each symbol produced in the first phase—operate in tandem to create the columns of the final pattern (the parallel phase). Several unrelated properties of the classes of patterns generated by various varieties of matrix grammars are announced.
6 citations
TL;DR: It is shown that one can determine whether a given grammar fits another given grammar, and it is established that the containment problem for Szilard languages is decidable.
Abstract: One of the methods for defining translations is the so called syntax-directed translation scheme which can be interpreted as a pair of rather similar grammars with the productions working in parallel. Because of the similarity of the grammars each of the two grammars “fits” the other in the sense that for each derivation process in one grammar leading to a terminal word the corresponding derivation process in the other grammar also leads to a terminal word. For many practical applications it suffices to consider the case that one of the grammars fits the other, but not necessarily conversely. Investigating this idea, translations are obtained which are more powerful than the syntax-directed. It is shown that one can determine whether a given grammar fits another given grammar. As a by-product, it is established that the containment problem for Szilard languages is decidable.
6 citations
01 Jan 1976
TL;DR: The precedence-graph-grammars is defined as a subclass of the context-free graph-grammar allowing for easier parsing algorithms.
Abstract: The syntactical analysis of pictures derived by a context-free graph-grammar is a rather complicated algorithm. Analogously to the development for Chomsky-grammars ten years ago we define the precedence-graph-grammars as a subclass of the context-free graph-grammars allowing for easier parsing algorithms. By table-lookup we can decide locally if an edge or a node is part of a handle and if it isn't in which direction to proceed to reach one.
5 citations
01 Jan 1976
TL;DR: The time therefore seems ripe to explore categorially based transformational grammars, obtained by taking an Ajdukiewicz categorial grammar as base and adding a transformational component, says David Lewis in his article ‘General Semantics’ (1972).
Abstract: In his article ‘Some Linguistic Obstacles to Machine Translation’ (1960) Yehoshua Bar-Hillel dealt with the merits of categorial grammar for the analysis of certain kinds of simple sentences, the so-called kernel sentences, and with the shortcomings of categorial grammar in regard to more complex sentences. He followed Chomsky in that he proposed that categorial grammar “has to be supplemented by additional procedures, the so-called transformations” (Bar-Hillel 1960, p. 83). More than 10 years later the same stand was taken by David Lewis in his article ‘General Semantics’ (1972): “The time therefore seems ripe to explore categorially based transformational grammars, obtained by taking an Ajdukiewicz categorial grammar as base and adding a transformational component. So far as I know, this proposal has been made only once before (Lyons, 1966), but it seems an obvious one”. The motivation for the call for a transformational component is the same as in Bar-Hillel (1960). Lewis says very little about this component, only that he assumes that, if a problem arises in categorial grammar, transformations will handle it. Lewis puts one restriction on the transformational component: “In fact the only restriction I place on syntax is that transformational grammars should be categorially based”; what that means is obscured by the next sentence “In other words: a transformational component should operate on a set of categorial phrase markers representing a set of meanings generated by some lexicon” Lewis, (1972, p. 190).
TL;DR: A practical top-down parsing method which is a part of a general purpose translation machine automaton, which provides for the convenient and efficient specification of linguistic constructs which are difficult or lengthy to specify in BNF metalanguage.
Abstract: The top-down method of parsing programming languages has been widely used in commercially available compilers. Suprisingly, techniques for automating syntax-directed, top-down parsing have not been widely available. This paper describes a practical top-down parsing method which is a part of a general purpose translation machine automaton. The syntactical description capabilities provide for the convenient and efficient specification of linguistic constructs which are difficult or lengthy to specify in BNF metalanguage. The translation machine, which provides for semantic as well as syntactic operations, has been designed for implementation in hardware, microcode, or software. The translation machine can be utilized for convenient and efficient construction of a wide variety of programs that perform source string to object string transformations.
TL;DR: In this article, a number of long standing confusions that have blurred thinking and prejudiced attitudes towards the whole issue of translation are identified and dealt with, as well as the atittudes toward and the development and applications of the Bilingual Assumption or translation principle are traced and examined in the light of the foregoing analysis.
Abstract: When translation is discussed there are actually two separate issues at stake. One is the "pure" issue of the principle of semantic demonstration of Second Language items via First Language items. The other is the "applied" issue of the pedagogical applications of the principle. Confusion ensues not only as the result of the same word "translation" being used to denote both issues but also because different types of translation are lumped under the same term. The inherent validity of the translation principle, given the fact that there can be degrees of semantic overlap between ostensible equivalents, and its relative validity vis a vis the other modes available for conveying the meaning of L, items are analyzed and evaluated. In the process a number of long standing confusions that have blurred thinking and prejudiced attitudes towards the whole issue of Translation are identified and dealt with. Finally, the atittudes toward and the development and applications of the Bilingual Assumption or translation principle are historically traced and examined in the light of the foregoing analysis.
01 Aug 1976
TL;DR: A method is discussed that maps theorem proving using clause interconnectivity graphs onto formal grammars and the languages generated by the grammARS relate to the proofs of the theorems.
Abstract: : A method is discussed that maps theorem proving using clause interconnectivity graphs onto formal grammars. The languages generated by the grammars relate to the proofs of the theorems. (Author)
01 Feb 1976
TL;DR: In this paper, the notion of interactive languages generated by interactions between two phrase-structure grammars is proposed and discussed, and it is shown that a family of context-free languages does not include interactive languages between two regular Grammars and vice versa.
Abstract: The notion of interactive languages generated by interactions between two phrase-structure grammars are proposed and discussed. It is shown that a family of context-free languages does not include a family of interactive languages between two regular grammars and vice versa. The family of interactive languages, however, is not closed under any of the ordinary operations. The paper also includes discussions about n-cyclic interactive languages among n grammars.
01 Dec 1976
TL;DR: The GIST (Grammar Instructed Structure) analyzes English sentences, using a grammar which provides a partial interpretation of sentences, and some guidelines towards a more complete understanding.
Abstract: : This paper shows the computation of English sentences in different task domains--the robot world, a children's story, and the front-end of information retrieval. The GIST (Grammar Instructed Structure) analyzes these sentences, using a grammar which provides a partial interpretation of sentences, and some guidelines towards a more complete understanding. (Author)
TL;DR: This work gives a unified approach to the problem of grammatical parsing and to the problems of organizing the output of parsers to lead naturally to the notion of label languages and control sets induced by canonical derivations.
Abstract: The concepts of “right parse” and “left parse” to represent the outputs of bottom-up and top-down parsers (respectively) of context-free grammars are extended in a natural way to cover all phrase-structure grammars. The duality between left and right parses is demonstrated. Algorithms are presented for converting between parses and the “derivation languages.” The derivation languages give the most efficient representation of the syntactical structure of a word in a grammar. This work gives a unified approach to the problem of grammatical parsing and to the problems of organizing the output of parsers. The general theory of parses then leads naturally to the notion of label languages and control sets induced by canonical derivations.