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The Concept of a Linguistic Variable and its Application to Approximate Reasoning

by L. A. Zadeh - Journal of Information Science , 1975
"... By a linguistic variable we mean a variable whose values are words or sentences in a natural or artificial language. I:or example, Age is a linguistic variable if its values are linguistic rather than numerical, i.e., young, not young, very young, quite young, old, not very oldand not very young, et ..."
Abstract - Cited by 1427 (9 self) - Add to MetaCart
By a linguistic variable we mean a variable whose values are words or sentences in a natural or artificial language. I:or example, Age is a linguistic variable if its values are linguistic rather than numerical, i.e., young, not young, very young, quite young, old, not very oldand not very young, etc., rather than 20, 21, 22, 23, In more specific terms, a linguistic variable is characterized by a quintuple (&?, T(z), U, G,M) in which &? is the name of the variable; T(s) is the term-set of2, that is, the collection of its linguistic values; U is a universe of discourse; G is a syntactic rule which generates the terms in T(z); and M is a semantic rule which associates with each linguistic value X its meaning, M(X), where M(X) denotes a fuzzy subset of U The meaning of a linguistic value X is characterized by a compatibility function, c: l / + [0, I], which associates with each u in U its compatibility with X. Thus, the COItIpdtibiiity of age 27 with young might be 0.7, while that of 35 might be 0.2. The function of the semantic rule is to relate the compdtibihties of the so-called primary terms in a composite linguistic value-e.g.,.young and old in not very young and not very old-to the compatibility of the composite value. To this end, the hedges

Procedural Modeling of Buildings

by Pascal Müller, Peter Wonka, Simon Haegler, Andreas Ulmer, Luc Van Gool , 2006
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Abstract - Cited by 254 (22 self) - Add to MetaCart
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Towards an Engineering Discipline for GRAMMARWARE

by Paul Klint, Ralf Lämmel, Chris Verhoef , 2003
"... Grammarware comprises grammars and all grammar-dependent software. The term grammar is meant here in the sense of all established grammar formalisms and grammar notations including context-free grammars, class dictionaries, XML schemas as well as some forms of tree and graph grammars. The term gramm ..."
Abstract - Cited by 146 (7 self) - Add to MetaCart
Grammarware comprises grammars and all grammar-dependent software. The term grammar is meant here in the sense of all established grammar formalisms and grammar notations including context-free grammars, class dictionaries, XML schemas as well as some forms of tree and graph grammars. The term grammar-dependent software refers to all software that involves grammar knowledge in an essential manner. Archetypal examples of grammar-dependent software are parsers, program converters, and XML document processors. Despite the pervasive role of grammars in software systems, the engineering aspects of grammarware are insufficiently understood. We lay out an agenda that is meant to promote research on increasing the productivity of grammarware development and on improving the quality of grammarware. To this end, we identify the problems with the current grammarware practises, the barriers that currently hamper research, the promises of an engineering discipline for grammarware, its principles, and the research challenges that have to be addressed.
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Automatic Code Generation from Design Patterns

by Frank Budinsky, Marilyn Finnie, Patsy Yu, John Vlissides - IBM Systems Journal , 1996
"... Design patterns raise the abstraction level at which people design and communicate design of object-oriented software. But design patterns still leave the mechanics of their implementation to the programmer. This paper describes the architecture and implementation of a tool that automates the implem ..."
Abstract - Cited by 132 (1 self) - Add to MetaCart
Design patterns raise the abstraction level at which people design and communicate design of object-oriented software. But design patterns still leave the mechanics of their implementation to the programmer. This paper describes the architecture and implementation of a tool that automates the implementation of design patterns. The user of the tool supplies application-specific information for a given pattern, from which the tool generates all the pattern-prescribed code automatically. The tool has a distributed architecture that lends itself to implementation with off-the-shelf components. 1
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Grammatical Framework: A Type-Theoretical Grammar Formalism

by Aarne Ranta , 2003
"... Grammatical Framework (GF) is a special-purpose functional language for defining grammars. It uses a Logical Framework (LF) for a description of abstract syntax, and adds to this a notation for defining concrete syntax. GF grammars themselves are purely declarative, but can be used both for lineariz ..."
Abstract - Cited by 99 (23 self) - Add to MetaCart
Grammatical Framework (GF) is a special-purpose functional language for defining grammars. It uses a Logical Framework (LF) for a description of abstract syntax, and adds to this a notation for defining concrete syntax. GF grammars themselves are purely declarative, but can be used both for linearizing syntax trees and parsing strings. GF can describe both formal and natural languages. The key notion of this description is a grammatical object, which is not just a string, but a record that contains all information on inflection and inherent grammatical features such as number and gender in natural languages, or precedence in formal languages. Grammatical objects have a type system, which helps to eliminate run-time errors in language processing. In the same way as an LF, GF uses...

Reference Attributed Grammars

by Görel Hedin - SECOND WORKSHOP ON ATTRIBUTE GRAMMARS AND THEIR REFERENCE APPLICATIONS ATTRIBUTED – GRAMMARS WAGA99 , 1999
"... An extension to canonical attribute grammars is introduced, permitting attributes to be references to arbitrary nodes in the syntax tree, and attributes to be accessed via the reference attributes. Important practical problems such as name and type analysis for object-oriented languages can be expre ..."
Abstract - Cited by 96 (17 self) - Add to MetaCart
An extension to canonical attribute grammars is introduced, permitting attributes to be references to arbitrary nodes in the syntax tree, and attributes to be accessed via the reference attributes. Important practical problems such as name and type analysis for object-oriented languages can be expressed concisely in these grammars, and an optimal evaluation algorithm is available. The proposed formalism and algorithm have been implemented in an interactive language development tool.

Incremental context-dependent analysis for language-based editors

by Thomas Reps, Tim Teitelbaum, Alan Demers - ACM Transactions on Programming Languages and Systems , 1983
"... Knowledge of a programming language's grammar allows language-based editors to enforce syntactic correctness at all times during development by restricting editing operations to legitimate modifications ot ~ the program's context-free derivation tree; however, not all language constraints ..."
Abstract - Cited by 91 (10 self) - Add to MetaCart
Knowledge of a programming language's grammar allows language-based editors to enforce syntactic correctness at all times during development by restricting editing operations to legitimate modifications ot ~ the program's context-free derivation tree; however, not all language constraints can be enforced in this way because not all features can be described by the context-free formalism. Attribute grammars permit context-dependent language features to be expressed in a modular, declarative fashion and thus are a good basis for specifying language-based editors. Such editors represent programs as attributed trees, Which are modified by operations such as subtree pruning and grafting. Incremental analysis is performed by updating attribute values after every modification. This paper discusses how updating can be carried out and presents several algorithms for the task, including one that is asymptotically optimal in time.
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Attribute Grammars as a Functional Programming Paradigm

by Thomas Johnsson - Functional Programming Languages and Computer Architecture, volume 274 of LNCS , 1987
"... The purpose of this paper is twofold. Firstly we show how attributes in an attribute grammar can be simply and efficiently evaluated using a lazy functional language. The class of attribute grammars we can deal with are the most general ones possible: attributes may depend on each other in an arbitr ..."
Abstract - Cited by 90 (2 self) - Add to MetaCart
The purpose of this paper is twofold. Firstly we show how attributes in an attribute grammar can be simply and efficiently evaluated using a lazy functional language. The class of attribute grammars we can deal with are the most general ones possible: attributes may depend on each other in an arbitrary way, as long as there are no truly circular data dependencies. Secondly, we describe a methodology based on attribute grammars, where, in a fairly straightforward way, we can develop efficient functional programs where direct, conventional solutions yield less efficient programs. We review two examples from a paper by R. Bird (Using circular programs to eliminate multiple traversals of data, Acta Informatica, 21, 1984) where he transforms simple but inefficient multipass programs into more efficient single pass ones, but which on their own can be very hard to understand. We show how such efficient but tangled programs can have natural formulations as attribute grammars. We also propose a...
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Higher Order Attribute Grammars

by S. D. Swierstra, H.H. Vogt, Doaitse Swierstra, Harald Vogt T , 1991
"... Higher Order Attribute Grammars (HAGs) are an extension of normal attribute grammars in the sense that the distinction between the domain of parse-trees and the domain of attributes has disappeared: parse trees may be computed in attributes and grafted to the parse tree at various places. As a re ..."
Abstract - Cited by 83 (8 self) - Add to MetaCart
Higher Order Attribute Grammars (HAGs) are an extension of normal attribute grammars in the sense that the distinction between the domain of parse-trees and the domain of attributes has disappeared: parse trees may be computed in attributes and grafted to the parse tree at various places. As a result semantic functions may be described by attribute evaluation.

Constraint propagation

by Christian Bessiere - Handbook of Constraint Programming , 2006
"... Constraint propagation is a form of inference, not search, and as such is more ”satisfying”, both technically and aesthetically. —E.C. Freuder, 2005. Constraint reasoning involves various types of techniques to tackle the inherent ..."
Abstract - Cited by 76 (5 self) - Add to MetaCart
Constraint propagation is a form of inference, not search, and as such is more ”satisfying”, both technically and aesthetically. —E.C. Freuder, 2005. Constraint reasoning involves various types of techniques to tackle the inherent
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