An NC algorithm for recognizing tree adjoining languages

Authors

Michael A. Palis, Newark College of Engineering
Sunil M. Shende, UNL College of Engineering

Document Type

Article

Publication Date

4-1-1992

Abstract

A parallel algorithm is presented for recognizing the class of languages generated by tree adjoining grammars, a tree rewriting system which has applications in natural language processing. This class of languages is known to properly include all context-free languages; for example, the noncontext-free sets {aⁿbⁿcⁿ} and {ww} are in this class. It is shown that the recognition problem for tree adjoining languages can be solved by a concurrent read, concurrent write parallel random-access machine (CRCW PRAM) in O(log n) time using polynomially many processors. Thus, the class of tree adjoining languages is in AC¹ and hence in NC. This extends a previous result for context-free languages. © 1992 Plenum Publishing Corporation.

Identifier

34249837542 (Scopus)

Publication Title

International Journal of Parallel Programming

External Full Text Location

https://doi.org/10.1007/BF01408291

e-ISSN

15737640

ISSN

08857458

First Page

151

Last Page

167

Issue

2

Volume

21

Recommended Citation

Palis, Michael A. and Shende, Sunil M., "An NC algorithm for recognizing tree adjoining languages" (1992). Faculty Publications. 17305.
https://digitalcommons.njit.edu/fac_pubs/17305