Stephen M Post

US Patent:

49145908, Apr 3, 1990

Filed:

May 18, 1988

Appl. No.:

7/195237

Inventors:

Robert B. Loatman - Vienna VA
Stephen D. Post - McLean VA
Chih-King Yang - Rockville MD
John C. Hermansen - Catharpin VA

Assignee:

Emhart Industries, Inc. - Indianapolis IN

International Classification:

G06F 1521
G06F 1518
G06K 962

US Classification:

364419

Abstract:

A hybrid natural language understanding (NLU) system which is particularly designed for processing natural language text. Primary functional components of the NLU system include a preprocessor; a word look-up and morphology module which communicates with a lexicon and a learning module; a syntactic parser which interfaces with an augmented transition network (ATN) grammar; a case frame applier, which converts the syntactic structure into canonical, semantic "case frames"; and a discourse analysis component which integrates explicit and implied information in the text into a conceptual structure which represents its meaning. This structure may be passed on to a knowledge based system, data base, to interested analysts or decision makers, etc. Significant feedback points are provided, e. g. , the case frame applier may notify the syntactic parser of a semantically incorrect parse, or the syntactic parser may seek a semantic judgment based on a fragmentary parse.