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Cross-referencing and Thesaurus maintenance
Get PDFThe development of thesauri in science and technology is briefly discussed. The important aspects of the structure and format of a thesaurus are mentioned.
The need for revising a thesaurus, the structural changes that may occur in course of time, and the problems of maintaining a thesaurus are indicated. It is the need that should determine the frequency of revision, rather than any other exigency. The types of relations implied in the cross-reference structures in thesauri are briefly discus-
sed. The cross-reference structures in TEST, Thesaurofacet, INIS The Stresses the point that the policy regarding saurus etc, are examined. the cross-referencing in thesauri should be stated explicitly, if proper and
useful studies are to be undertaken regarding the cross-reference structures, and points out that such a policy statement is of help in the maintenance of thesauri and usable form. The two types of approaches suggested Kochen and others for the study of properties of cross-reference of
structures are mentioned
Theoretical foundations of thesaurus construction
Get PDFThe theoretical foundations of recent work on automatic and semiautomatic
thesaurus construction are briefly but critically reviewed, and
limitations of current methods of automatic construction of thesaurus are
pointed out. Need for a deeper study of the theoretical foundations of thesaurus
construction is emphasized and a line of approach to it is suggested
Semi-automatic construction of Thesaurus
Get PDFDescribes computer program for generating a thesaurus from Feature Heading of a Bibliographical Record. Also
gives a description of computer program for constructing synonym subject string.
Programs are written in COBOL. Gives flow charts and a sample of thesaurus output
Thesaurus - an ideal tool for vocabulary control in post-coordinate systems : INIS Thesaurus - a case study
Get PDFThe complex conceptual relationships contained in multi-dimensional documents present the problem of inconsistency in subject analysis and vocabulary control for efficient retrieval is stressed. The development of Thesaurus, an important contribution for effective vocabulary control in mechanised IR systems which is among the many developmental efforts in this direction, is highlighted. The development, structure and design of INIS Thesaurus is given in detail. Adaptability of the INIS thesaurus to a computer-based information handling system is examine
Query formulation and Feed-back study for a Thesaurus based Information System
Get PDFQuery formulation is an output activity just as indexing is an input activity. Query formulation techniques are discussed, with reference to the International Nuclear Information System (INIS), its thesaurus and its data base. The improvement of query by feed-back study is examined. Different techniques of evaluating the retrieval of documents and simple mathematical expressions to calculate recall ratio and pertinence ratio are given. The ranking of pertinency of documents and its utility is discussed
Thesaurus and Classification Scheme : a study of the compatibility of the principles for consturction of thesaurus and classification scheme
No full textThe performance of an Information Retrieval System can be improved by the use of controlled vocabularies, such as, classification schemes, subject authority lists and thesauri. Recent trends in the field of design of different types of controlled vocabularies have developed exclu-
sively, principles and rules for each one of these devices. While it is admitted that there are certain essential differences in each of these types of controlled vocabularies, there are also certain features which emphasize basic similarity, interconvertibility and compatibility among them. This paper discusses the compatibility of the guiding principles provided by the ISO for the construction of a thesaurus and the principles available in the General Theory of Library Classification. It is found that there are several initial steps which are common for construction of both a thesaurus and a classification scheme.
The thesaurus usually confines itself to
two planes of work, the idea plane and the verbal plane, whereas the classification system spreads into three planes of work, idea plane, verbal plane and the notational plane. The verbal plane of thesaurus actually
takes some of the roles of the notational plane of a classification scheme. It is found that the role of thesaurus, classification scheme and that. of a
subject heading. list can coexist and used harmoniously in an integrated library and information system
NASA Thesaurus in Information Retrieval
Get PDFA brief account of the NASA Thesaurus is presented. Some typical problems encounted in information search using the subject indexes to the Scientific and Technical Aerospace REports (STAR) and International Aerospace Abstracts which are compiled using NASA Thesaurus, are mentioned. Use of facet analysis and synthesis based on S R Ranganathan's subject structure model is recommended for use along with the thesaurus to secure precise and consistent search formulation for compound subjects
Work and Time analysis for rendering terms in a thesaurus derived from a faceted classification schedule : a case study with Lathe Production
Get PDFDescribes the various steps involved in rendering a standard term. Identifies the difference in the role of the term occuring in a faceted classification schedule. Analyses the work involved in the conversion, and the time required for each of the steps
Related Terms in Thesauri
Get PDFThe concept of "Related Term" (RT) in thesaurus is explained- The
method of handlingRTs in Thesaurofacet and the Thesaurus of Engineering
and Scientific Terms is examined in relation to the number of RTs listed,
common RTs in selected cases, and the different kinds of RT. Some tentative
quantitative findings are presented
Term-concept relationship in an Information Retrieval Thesaurus
Get PDFConcept representation in Thesauri, especially the representation of compound concepts, has been studied. The criteria and relative advantages in representing a compound concept either as a precombined descriptor or as a combination of elemental descriptors, are discussed with illustrative examples taken from Medical Subject Headings (MeSH) of the National Library of Medicine