Describes the theoretical framework of a retrieval system that uses data structures called bitmaps to improve search algorithms for medium-sized systems. Information retrieval systems that contain the full text of the documents are discussed, and the use of inverted files such as concordances for small texts is explained. (24 references) (LRW)

Analyzes the formal properties, structural consequences, similarities, and differences of link indicators, brackets, and cohesion separators in the query languages employed in information retrieval. Eleven figures, a 32-item reference list, and appendices on Extended Backus Notation and the formal definition of the Formal Relevance Language are…

Discusses the problems of compressing a large textual database for storage on CD-ROM. A text-compression algorithm is presented, new algorithms for compression of indices are described, and the ARTFL (American and French Research on the Treasury of the French Language) database is used as an example. (14 references) (LRW)

Proposes a single underlying structure for the production of a variety of computer index displays, using a networking system which represents both concepts and links by nodes. Desirable characteristics of index displays are outlined, and algorithmic extraction of subnetworks for local use is discussed. References are included. (Author/BK)

Examines through a series of mathematical models (theorems, descriptions, and examples), properties and operations on inverted files, which are used in an information retrieval system based on thesaurus with weighted descriptors. (CWM)