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)

Presents uniform and efficient approach for processing all truncated query terms in information retrieval which requires one disk access to obtain from the permuted dictionary all strings represented by truncated term. The problem of the overhead storage required to implement the permuted dictionary is discussed. Fifteen references are provided.…

Describes an indexing technique based on overlapping word fragments as reference strings that are linked in a directed graph structure which makes possible exact match-, partial match-, and masked-partial match-retrieval and indicates search strategies for each case. Eight figures, two tables, and nine references are provided. (RBF)

Words and word fragments from the computer-readable data bases "Chemical Abstracts Condensates" and "Biological Abstracts Previews" were analyzed in terms of length, number, and frequency of appearance to determine some parameters upon which inversion of these data bases could be predicated. Types (unique words or fragments)…

Discusses indexes for text databases and presents an efficient implementation of an index for text searching called PAT array, or suffix array, where the database is stored on secondary storage devices such as magnetic or optical disks. Additional hierarchical index structures and searching algorithms are proposed that improve searching time, and…

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)