You can use this Javascript to encode / decode url parameters. Script is fully compatible with UTF-8 encoding. It’s useful when u want to transfer data using AJAX technology, or for other operations which involve url parameter manipulation.

If you plan using UTF-8 encoding in your project don’t forget to set the page encoding to UTF-8 (Content-Type meta tag).

DEMO

Source code for webtoolkit.url.js

/**

*

* URL encode / decode

* http://www.webtoolkit.info/

*

**/

var Url = {

// public method for url encoding

encode : function (string) {

return escape(this._utf8_encode(string));

},

// public method for url decoding

decode : function (string) {

return this._utf8_decode(unescape(string));

},

// private method for UTF-8 encoding

_utf8_encode : function (string) {

string = string.replace(/

/g,"

");

var utftext = "";

for (var n = 0; n < string.length; n++) {

var c = string.charCodeAt(n);

if (c < 128) {

utftext += String.fromCharCode(c);

}

else if((c > 127) && (c < 2048)) {

utftext += String.fromCharCode((c >> 6) | 192);

utftext += String.fromCharCode((c & 63) | 128);

}

else {

utftext += String.fromCharCode((c >> 12) | 224);

utftext += String.fromCharCode(((c >> 6) & 63) | 128);

utftext += String.fromCharCode((c & 63) | 128);

}

}

return utftext;

},

// private method for UTF-8 decoding

_utf8_decode : function (utftext) {

var string = "";

var i = 0;

var c = c1 = c2 = 0;

while ( i < utftext.length ) {

c = utftext.charCodeAt(i);

if (c < 128) {

string += String.fromCharCode(c);

i++;

}

else if((c > 191) && (c < 224)) {

c2 = utftext.charCodeAt(i+1);

string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));

i += 2;

}

else {

c2 = utftext.charCodeAt(i+1);

c3 = utftext.charCodeAt(i+2);

string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));

i += 3;

}

}

return string;

}

}

http://cafe.naver.com/kinder67.cafe?iframe_url=/ArticleRead.nhn%3Farticleid=1749&

중심어주도형 구 구조 문법(HPSG)은 Carl Pollard와 Ivan Sag에 의해 개발된 비파생적

생성문법(non-derivational generative grammar)이다. 이것은 일반 구 구조 문법

(Generalised Phrase Structure Grammar)에 대해 즉각적인 후속문법(successor)이다.

HPSG는 컴퓨터 과학같은 다른 분야로부터 끌어 당이고 Ferdinand de Saussure의 신호(sign)에

대한 생각을 사용한다. HPSG는 균일한 형식주의를 사용하고 자연언어처리(natural language

processing)에 대해 흥미를 끄는 변화 방식으로 조직된다.

The Head-driven phrase structure grammar (HPSG) is a non-derivational generative grammar

theory developed by Carl Pollard and Ivan Sag (1985). It is the immediate successor to

Generalised Phrase Structure Grammar. HPSG draws from ot\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0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fields such as computer science

(data type theory and knowledge representation) and uses Ferdinand de Saussure's notion of

the sign. It uses a uniform formalism and is organized in a modular way which makes it

attractive for natural language processing.

HPSG 문법은 원칙 및 문법규칙 그리고 문법에 속하는 것으로 대개 생각되는 않는 사전(lexicon)

등록을 포함한다. 형식주의(formalisam)는 어휘론(lexicalism)에 기초를 둔다. 이것은 사전이

바로 등록 목록 이상이며, 자체적으로 충분히 구조화된다는 의미다. 개인 등록은 유형에 따라

뚜렷해진다. 유형은 위계(hierarchy)를 형성한다.

A HPSG grammar includes principles and grammar rules and lexicon entries which are normally

not considered to belong to a grammar. The formalism is based on lexicalism. This means

that the lexicon is more than just a list of entries, it is in itself richly structured.

Individual entries are marked with types. Types form a hierarchy.

HPSG가 다루는 기본유형은 신호이다. 단어와 구는 신호의 두 가지 상이한 하위유형이다. 하나의

단어는 두 가지 특징을 갖고 있다: 소리, 음성 형태와 구문론적 및 의미론적 정보, 이 두 가지

모두 하위특징에 든다. 신호와 규칙은 유형화된 특징 구조(feature structure)로서 형식을 갖춘다.

The basic type HPSG deals with is the sign. Words and phrases are two different subtypes of

sign. A word has two features: [PHON] (the sound, the phonetic form) and [SYNSEM]

(the syntactic and semantic information), both of which are split into subfeatures.

Signs and rules are formalised as typed feature structures.

HPSG 형식주의에 바탕을 둔 다양한 파서(parser)가 쓰여졌으며 최적화(optimization)는 최근에

탐구되고 있다. 독일어 문장을 분석하는 체계에 대한 사례는 브레멘 대학교에 의해 제공되고 있다.

네덜란드어의 경우 Groningen 대학교에 의해 개발된 the wide-coverage dependency parser Alpino가

있다. 다양한 언어의 거대한 HPSG 문법은 DELPH-IN 협동 네트워크에서 개발되고 있다. 독일어,

영어와 일본어의 폭넓은 적용범위 문법(wide-coverage grammar)은 open-source license 하에서

이용가능하다.

Various parsers based on the HPSG formalism have been written and optimizations are currently

being investigated. An example of a system analyzing German sentences is provided by the

University of Bremen . For Dutch, the wide-coverage dependency parser Alpino has been

developed by the University of Groningen. Large HPSG grammars of various languages are

being developed in the DELPH-IN [3] collaboration network. Wide-coverage Grammars of

German, English and Japanese are available under an open-source license.

See also

Generalised phrase structure grammar

Lexical functional grammar

syntax

Transformational grammar

External links

Head-Driven Phrase Structure Grammar, Stanford (includes on-line proceedings of an annual

HPSG conference)

Ohio State HPSG homepage

Delph-In network for HPSG grammar development

Excellent summary

Compares HPSG with alternatives, and offers historical perspective

Bibliography of HPSG Publications

"http://en.wikipedia.org/wiki/Head-driven_phrase_structure_grammar"

Categories: Generative linguistics | Grammar frameworks

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일반 구 구조 문법(GPSG)은 자연언어(natural language)의 문장론(syntax)

및 의미론(semantics)을 기술하기 위한 틀을 일컫는다. GPSG는 Gerald

Gazdar에 의해 1970년대 후반에 처음으로 발달되었다. 다른 공헌자들은

Ewan Klein, Ivan Sag과 Geoffrey Pullum을 포함한다. 그들의 책

<<Generalised Phrase Structure Grammar>>는 1985년

출판되었으며, 특히 영어 문장론에 적용됨으로써, GPSG에 관한 주요

모노그래프(monograph)이다.

Generalised phrase structure grammar (GPSG) is a framework for

describing the syntax and semantics of natural languages. GPSG

was initially developed in the late 1970s by Gerald Gazdar. Other

contributors include Ewan Klein, Ivan Sag, and Geoffrey Pullum.

Their book Generalised Phrase Structure Grammar, published in 1985,

is the main monograph on GPSG, especially as it applies to English

syntax.

GPSG의 최고 목표 가운데 하나는 자연언어의 문장론이, 통사론자(syntactician)의

경우 그러한 문법들이 보다 쉽게 쓰도록 의도된 어느 정도 적당한 관습과 함께,

문맥자유문법(context-free grammar)에 의해 기술될 수 있음을 보여주는 것이다.

이러한 관습 가운데 정교한 특징구조(feature structure) 체계이며 소위 "상위 규칙

(meta-rules)"이다. 상위 규칙은 문맥 자유 문법 생산물을 산출하는 규칙인 것이다.

GPS는 더 나아가 구문론적 도출 나무(syntactic derivation tree)로부터 문장의 합성적

의미(compositional meaning)를 산정하기 위해 사용될 수 있는 문장론적 주석(annotation)과

함께 구문론적 기술(syntactic description)을 진술한다. 하지만, 이러한 확장은 기본

문맥자유문법을 위해 사용되는 것보다 훨씬 높은 순서의 계산 복잡도(computational

complexity)에 대한 파싱 알고리즘(parsing algorithm)을 요구한다고 (예를 들어 Robert

Berwick에 의해) 주장되어 왔다

One of the chief goals of GPSG is to show that the syntax of natural languages can

be described by context-free grammars, with some suitable conventions intended to

make writing such grammars easier for syntacticians. Among these conventions are

a s\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0ophisticated feature structure system and so-called "meta-rules", which are rules

generating the productions of a context-free grammar. GPSG further augments syntactic

descriptions with semantic annotations that can be used to compute the compositional

meaning of a sentence from its syntactic derivation tree. However, it has been argued

(for example by Robert Berwick) that these extensions require parsing algorithms of a

higher order of computational complexity than those used for basic CFGs.

GPSG는 부분적으로 문장의 변형론(transformational theories of syntax)에 반한다. 사실

일반구구조문법에서 발달된 문맥자유문법에 표기법적 확장은 변형을 과하게 만든다고

주장되고 있다. 일반구구조문법에 대한 대부분의 구문론적 혁신은 그 결과로 중심어-주도형

구 구조 문법(head-driven phrase structure grammar)에 통합되었다. Gerald Gazdar와 많은

다른 통사론자(syntactician)들은 자연언어(natural language)가 사실 문맥자유문법에 의해

충분히 기술될 수 없다고 주장해왔다.

GPSG is in part a reaction against transformational theories of syntax. In fact, the

notational extensions to context-free grammars developed in GPSG are claimed to make

transformations redundant. Most of the syntactic innovations of GPSG were subsequently

incorporated into head-driven phrase structure grammar.

[1] Gerald Gazdar, and many other syntacticians, have since argued that natural

languages cannot in fact be adequately described by CFGs.

See also

Lexical functional grammar

Transformational grammar

External links

Gerald Gazdar's homepage, containing links to publications on GPSG.

"http://en.wikipedia.org/wiki/Generalised_phrase_structure_grammar"

Categories: Generative linguistics | Grammar frameworks

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언어학(linguistics)과 컴퓨터 과학(computer science)에서, 문맥 자유

문법은 모든 생산 법칙이 V → w 의 형태를 취하는 형식적 문법이다.

이때 V는 비종단 기호(nonterminal symbol)이며, w는 종단과/이나

비종단으로 구성된 문자열(string)이다. "문맥 자유"라는 용어는

비종단 V가 항상 w에 의해, 일어나는 문맥과는 상관 없이, 대치될

수 있다는 사실을 표현한다. 형식 언어(formal language)를 산출하는

문맥-자유 문법이 있다면, 형식언어는 문맥-자유이다.

In linguistics and computer science, a context-free grammar

(CFG) is a formal grammar in which every production rule is

of the form V → w where V is a nonterminal symbol and w is

a string consisting of terminals and/or non-terminals. The

term "context-free" 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the fact that the non-terminal

V can always be replaced by w, regardless of the context in

which it occurs. A formal language is context-free if there

is a context-free grammar that generates it.

문맥 자유 문법은 대부분의 프로그래밍 언어(programming language)의

문장론(syntax)을 기술하기에 충분할 만큼 강력하다; 사실, 대부분의

프로그래밍 언어의 문장론은 문맥 자유 문법을 사용하는 것으로

특징지워진다. 다른 한편으로, 문맥자유문법은 효과적인 파싱 알고리즘

(parsing algorithm)의 구성을 허락할 만큼 단순하다. 파싱알고리즘은,

given string의 경우, 문법으로부터 발생되는 것인지 그리고 어떻게

발생되는지를 결정한다. Earley parser는 그러한 알고리즘의 한 사례인

반면 LR과 LL parsers는 단지 문맥자유문법의 보다 제한적인 하위세트만을

다룬다.

Context-free grammars are powerful enough to describe the syntax of

most programming languages; in fact, the syntax of most programming

languages is specified using context-free grammars. On the other hand,

context-free grammars are simple enough to allow the construction of

efficient parsing algorithms which, for a given string, determine whether

and how it can be generated from the grammar. An Earley parser is an example

of such an algorithm, while LR and LL parsers only deal with more

restrictive subsets of context-free grammars.

BNF (Backus-Naur Form)는 문맥자유문법을 표현하기 위해 사용되는 가장

일반적인 표시법이다.

BNF (Backus-Naur Form) is the most common notation used to express

context-free grammars.

결코 모든 형식적 언어가 문맥 자유는 아니다 - 훨씬 잘 알려진

반례(counterexample)는 {aⁿbⁿcⁿ: n ≥ 0} 이며, 몇 개의 a를 포함한

string 세트로 동일한 수의 b와 동일한 수의 c를 뒤따르게 된다.

Not all formal languages are context-free — a well-known counterexample

is {aⁿbⁿcⁿ: n ≥ 0}, the set of strings containing some number of a's,

followed by the same number of b's and the same number of c's.

http://en.wikipedia.org/wiki/Context-free_grammar