Proposes and explains a new mechanism for controlling the access requests in information protection systems that is based on Newton's interpolating polynomial. Access control matrices are discussed; single-key-lock systems are described; relevant algorithms are explained; and an example of the new mechanism is included. (10 references) (LRW)

Presents system for automatic handling of ordered sets, states based on these sets, and differing points of view regarding Universe of Discourse. Aspects are represented by new logical "overlap" function with examples taken from Ranganathan's horse and carriage parable and several books involving four main concepts (history, geography,…

Presents new methods for compressing bit matrices in large information retrieval systems which exploit possible correlations between rows of words and columns of documents. Three encoding methods are tested and compared--Shannon-Fano, arithmetic, and Huffman--and an appendix discusses binomial coefficients. (20 references) (LRW)

Presents principles for determining profile of a system user based on analysis of co-occurrence of index terms in queries and pertinent documents. A procedure for determining index term weights, the information value of which depends on the degree of homogeneity of system users, is introduced. Three references are cited. (EJS)

This discussion of the structure of online databases and the structure of related subject disciplines focuses on terms used in a book about tropical diseases and terms used in the MEDLINE database for articles on these diseases. Matrices used are explained and Medical Subject Heading (MeSh) terms are examined. (16 references) (LRW)

Summarizes studies of pseudoclassification, a process of utilizing user relevance assessments of certain documents with respect to certain queries to build term classes designed to retrieve relevant documents. Conclusions are reached concerning the effectiveness and feasibility of constructing term classifications based on human relevance…

Discusses the use of citation networks for constructing measures of the relative standing of journals in scientific journal-to-journal networks. Topics addressed include eigenvectors; measuring the standing of national scientific communities; and an empirical comparison of two measures of standing, one considering the environment and one without…

Discusses trade-off analysis, a data collection method with conjoint measurement technique in which respondents rank order a matrix of pairs of levels of specific attributes, and gives examples for use in determining library users' perceptions of relative utility of completeness of information versus cost of a search. Twelve sources are cited.…

Presents methods of information query building in selective dissemination of information systems based on user's publications and examines possible compatibility between user's information queries and his publications. Methods of information query construction determined by logical operators AND, OR, NOT and set of weighted keywords are described.…