Addressing the problem of protecting confidential information and data stored in computer databases from access by unauthorized parties, this paper details coding schemes which present such astronomical work factors to potential code breakers that security breaches are hopeless in any practical sense. Two procedures which can be used to encode for…

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)

Analyzes the properties of genetic sequences that cause the failure of classical algorithms used for data compression. A lossless algorithm, which compresses the information contained in DNA and RNA sequences by detecting regularities such as palindromes, is presented. This algorithm combines substitutional and statistical methods and appears to…

This paper describes and evaluates a computerized system, MATCH, which is being used in South Carolina to match or link student records from year to year. The functioning of MATCH and its specific features are described, and its use in matching student test scores is detailed. The problem of mismatched records and the use of visual editing to…

Discusses the Science Library Catalog, an online catalog intended for use by children at the Los Angeles Public Library, and describes the process of reorganizing the MARC-based database by using clustering algorithms to extend the Dewey Decimal Classification. Examples of screen displays are included. (18 references) (LRW)