摘要:

AbstractThere is a great need for a systematic approach to the specification, design, and development of information systems. This article describes the motivating reasons for such an approach and surveys some of the techniques that have been developed to assist the software specification and design activity. A methodology is seen as a combination of tools and techniques employed within an organizational and managerial framework that can be consistently applied to successive information system development projects. The ways that information system development organizations can create and use such methodologies are emphasized.

ISSN:0002-8231    

DOI:10.1002/asi.4630310102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractThis article raises several questions regarding training for computer‐based reference services, including who is to be trained and who is responsible for training. It discusses these issues and then provides a summary of the training provided to date by search service suppliers, database suppliers, library schools and extension programs, library cooperatives, and professional organizations. The available training materials are also discussed. Some projections are made of likely future activitie

ISSN:0002-8231    

DOI:10.1002/asi.4630310103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractCitation databases can be readily partitioned by examining the extent to which journals “feed back” to one another. A method has been developed to divide large files into clusters of journals without requiring the use of arbitrary starting points. Results are discussed relative to biomedical literature, and these findings are shown to be subsumed under a more general hypothesis regarding the structure of scientific literat

ISSN:0002-8231    

DOI:10.1002/asi.4630310104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractThe concept of bibliographic control (BC) is explored from its origin to its development into Universal Bibliographic Control (UBC). It is analyzed as to its functions and operations, namely (a) the form‐oriented or descriptive function, (b) the transcription of descriptive data onto a document surrogate, (c) the sequential ordering of these surrogates, and (d) the content‐oriented or exploitative function. It is shown that as a control system, BC is subject to the laws of cybernetics. Only the descriptive, transcriptive, and ordering functions of a BC system can be subjected to full control governed by generally applicable rules, while the content‐oriented retrieval function, being based on subjective judgments of relevance by indexers and ultimate users, are not completely controllable. The attainable limits of BC and UBC can thus be establ

ISSN:0002-8231    

DOI:10.1002/asi.4630310105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractOn‐line bibliographic search systems tend to increase the visibility of spelling errors through the use of indexes of unique terms; even low error rates in a data base can result in large numbers of misspelled terms in these indexes. This article describes the techniques used to detect and correct spelling errors in the data base of Chemical Abstracts Service. A computer program for spelling error detection achieves a high level of performance using hashing techniques for dictionary look‐up and compression. Heuristic procedures extend the dictionary and increase the proportion of misspelled words in the words flagged. Automatic correction procedures are applied only to words which are known to be misspelled; other corrections are performed manually during the normal editorial cycle. The constraints imposed on the selection of a spelling error detection technique by a complex data base, human factors, and high‐volume production are disc

ISSN:0002-8231    

DOI:10.1002/asi.4630310106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractThe retrieval performance of a technique for automated indexing using a controlled vocabulary (machine‐aided indexing) is compared with that of a Key Word Out of Context Index (KWOC). Twenty subject searches were performed using a data base of 635 summaries of Defense management data. Results show an average recall measurement of 0.73 for machine‐aided indexing and 0.79 for the KWOC index. The average relevance measurements were 0.62 for machineaided indexing and 0.60 for the KWOC in

ISSN:0002-8231    

DOI:10.1002/asi.4630310107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractThe average citation per article in chemistry by age of citation is related to the Poisson frequency distribution. This provides a formula for calculation of a half‐life for chemistry which depends on the structure of the research front exhibited in the literatur

ISSN:0002-8231    

DOI:10.1002/asi.4630310108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

ISSN:0002-8231    

DOI:10.1002/asi.4630310109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

ISSN:0002-8231    

DOI:10.1002/asi.4630310101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY