With the rapid development of information technology, various online education platforms support the sharing of digital educational resources. Because digital educational resources are simple to duplicate and disseminate quickly, there exists copyright infringement, which threatens the interests of copyright owners. In addition, the existing…

Explores the new storage technology of optical data disks and introduces a data structure, the inverted signature tree, for storing data on optical data disks for efficient text searching. The inverted signature tree approach is compared to the use of text signatures and the B+ tree. (22 references) (Author/CLB)

Investigates applicability of inverted file processing in magnetic bubble memories by presenting four magnetic bubble memory models as storage mediums: one based on a major-minor loop configuration; one utilizing a decoder design on a magnetic bubble memory chip; and two based on different structural configurations of the first two. (MBR)

The Inverted File Information Retrieval System (INFIRS), is a document search system which offers a comprehensive range of search facilities. It has been developed at the United Kingdom Chemical Information Service (UKCIS) as a general purpose retrieval tool, suitable for handling a wide variety of data-bases (both free-text and controlled…

Analyzes computer terminal memory performance in terms of overflow probability and average queueing delay, and presents new method to derive a closed expression for data arrivals with Erlangly distributed interarrival times and an approach to derive steady state probability expressions of the terminal memory content process. Twenty references are…

Response time in large, inverted file document retrieval systems is determined by time required to access files of document identifiers on disk and process a Boolean search request. A specialized computer system has been devised that can perform a complicated sample search involving 70 terms and over 60,000 document references 12 to 60 times…

This report delineates the theory and terminology of data compression. It surveys four data compression methods--null suppression, pattern substitution, statistical encoding, and telemetry compression--and relates them to a standard statistical coding problem, i.e., the noiseless coding problem. The well defined solution to that problem can serve…

The report describes an experimental study involving an on-line placement system in Boulder, Colorado which permitted applicants to request information from a terminal on any job stored in the computer. Data were collected on applicants referred by the Employment Service: whether or not hired, reason for not being hired if not hired, applicant…

Presents three text compression methods of increasing power and evaluates each based on the trade-off between compression gain and processing time. The advantages of using hash coding for speed and optimal arithmetic coding to successor information for compression gain are discussed. (26 references) (Author/CLB)

A syntax methodology provides a descriptive mechanism to enable machine readable storage and retrieval of numeric data contained in bibliographic documents. The body of this paper treats the nature of "the syntax,""the data element," and the language by which this syntax is expressed. A discussion of the methodology illustrates…

The purpose of the research described in the report is twofold. First, it is to analyze the relative benefits and costs of on-line computerized placement systems. The techniques developed for such an analysis which might be useful in evaluating other manpower programs are presented. Second, it is to provide a prototype model which shows how…

The file organization for the computerized Flora North America (FNA) data bank is described. A four level character hierarchy allows subdivision of any flora description into as many as four levels in order to specify plant character precisely. Terms at any one level will not necessarily be parallel in status. Both PLANTS and LEAVES serve as…

This is a progress report on a project attempting to design a system of compacting text for storage appropriate to disc oriented demand searching. After noting a number of previously designed methods of compression, it offers a tentative solution which couples a dictionary of most frequent character-strings with a set of variable-length codes. The…

Reports a survey conducted by the Bibliographical Center for Research to determine the extent of variations for entering local data on the part of BCR OCLC libraries. The results are presented along with a discussion of alternative practices and their impact on the processing of OCLC tapes. References are included. (Author/RAA)

A committee on rules fur cataloging machine readable data files (MRDF) recommends areas for revision of the Anglo American Cataloging Rules to integrate collections of MRDF into the mainstream of bibliographic control. The 12 working papers which support and detail these recommendations are appended to this report. They include rationales for…