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The history of the Universal Standard Bibliographic Code (USBC) is traced from its original concept as a machine generated control number to its present status as a means of merging catalogues, eliminating duplication and providing quality control in machine‐based bibliographic databases. Details are given of the early research work, the feasibility study that was carried out in connection with the United Kingdom Library Database System (UKLDS), the DOCMATCH Project and the work on expert systems. A resumé is given of the present work and proposed areas for research.

The Subject‐Object Relationship Interface model (SORI) described in this paper is a novel approach that displays many of the structures necessary to map between the conceptual level and the external level in a database management system, which is an information‐oriented view of data. The model embodies a semantic synthesiser, which is based on an algorithm that maps the syntactic representation of a tuple or a record onto a semantic representation. This is based on table‐driven semantics which are embedded in the database model. The paper introduces a technique for translating tuples into natural language sentences, and discusses a system that has been fully implemented in PROLOG.

Genetic algorithms are a class of non‐deterministic algorithms that derive from Darwinian evolution and that provide good, though not necessarily optimal, solutions to combinatorial problems. We describe their application to the identification of characteristics that occur approximately equifrequently in a database, using two different methods for the creation of the chromosome data structures that lie at the heart of a genetic algorithm. Experiments with files of English and Turkish text suggest that the genetic algorithm developed here can produce results superior to those produced by existing non‐deterministic algorithms; however, the results are inferior to those produced by an existing deterministic algorithm.

Although “coding”, whether for document retrieval, information transmission, error detection, etc., has generally provided a number of valid practical techniques for satisfying user functional requirements, it has not so far been developed into a complete and coherent methodology which integrates these techniques into an overall and objective cycle. The aim of this paper is to analyse and present formally all the components of an integrated automatic coding system with the employment of axiomatic set‐theoretic principles.

Discusses DOCMATCH, the project designed to test the feasibility of automatically matching document requests derived from database hosts with articles on the ADONIS workstation, achieved using Universal Standard Bibliographic Codes (USBCs). Considers the problems of matching requests that did not originate from database hosts where the bibliographic information was of a poorer quality. Finally, examines the relative merits of different serial article identification schemes.

This paper describes research work carried out with the aim to investigate dynamically evolving database environments and corresponding schemata, allowing storage and manipulation of variable length data, a variable number of fields per record, variable length records, manipulation of authority records and links between records and fields, and dynamically defined objects (relations in the traditional sense). The paper proposes a new framework for the definition of a unified schema that eliminates completely the need for reorganisation at both logical and internal levels. Retrieval of data is optimised through self‐contained storage chunks that also vary dynamically.

This investigation into the structure of MARC records begins by summarising the findings of Williams and Shefner who analysed the 1974/75 Library of Congress MARC II database. Various changes in the average size of the records and the occurrence of fields was noted when compared with a previous study by Swanson in 1969/70. However, the Bradford investigation set out to establish the average size and occurrence of the various elements in each record on the UK MARC tape for 1975. After describing the methodology, the paper presents the results under eight headings. There are three tables giving details of the occurrence and rank of subfield codes. Two graphs show the frequency distribution of all unique subfields. The paper ends by stating that the study was concerned more with the factual results than with any conclusions. However, the facts in the analysis should enable the cost of COM catalogue production and the inclusion or omission of an element from the records to be calculated. 3 refs.

This paper provides an introduction to the use of n‐grams in textual information systems, where an n‐gram is a string of n, usually adjacent, characters extracted from a section of continuous text. Applications that can be implemented efficiently and effectively using sets of n‐grams include spelling error detection and correction, query expansion, information retrieval with serial, inverted and signature files, dictionary look‐up, text compression, and language identification.

The purpose of this paper is to compare the use of two Object-Relational models against the use of a post-Relational model for a realistic application. Although real-world applications, in most cases, can be adequately modeled by the Entity-Relationship (ER) model, the transformation to the popular Relational model alters the representation of structures common in reality, like multi-valued and composite fields. Alternative database models have been developed to overcome these shortcomings.

Based on the ER model of a medical application, this paper compares the information representation, manipulation and enforcement of integrity constraints through PostgreSQL and Oracle, against the use of a post-Relational model composed of the Conceptual Universal Database Language (CUDL) and the Conceptual Universal Database Language Abstraction Level (CAL).

The CAL/CUDL pair, although more periphrastic for data definition, is simpler for data insertions, does not require the use of procedural code for data updates, produces clearer output for retrieval of attributes, can accomplish retrieval of rows based on conditions that address composite data with declarative statements and supports data validation for relationships between composite data without the need for procedural code.

To verify, in practice, the conclusions of the paper, complete implementation of a CAL/CUDL system is needed.

The use of the CAL/CUDL pair would advance the productivity of database application development.

This paper highlights the properties of realistic database-applications modelling and management that are desirable by developers and shows that these properties are better satisfied by the CAL/CUDL pair.