The paper explains in detail the quality and cost of the Packet Switched Public Data Network (PSPDN) by on line searching of the databases in the network of three information units in Beijing and a conclusion is thus drawn by the authors that PSPDN is superior to the telephone network in both communication quality and communication cost. The paper also give some comments on the databases in the networking of the above three units from the view of the user.
This paper introduces a method in which the dictionary s text file of a special database can be produced using CDS/ISIS output functions of terms dictionary. By filtering out the non-subject lines of the dictionary file, a file that only includes subject terms and their use-frequency will be created. The Chinese thesaurus of a speciality can be produced or apdated with the above use-frequency data of the subject terms.
This paper discusses the importance on selecting suitable search terms and the common ways of selecting such terms, which points out that on-line expansion function should be an important part of the on-line retrieval system in order to provide users with a friendly retrieval environment. Through the example of Tongji Information Retrieval Network System (TJIRNS), the paper mainly describes on-line expansion function and its implementation under the specific conditions.
The relation between cooperation network technology and open system with developmental strategy of library automation are discussed in this paper. With the concept of CISC/RISC, Unix, ISO/OSI and comprehensive computing environment are presented. Final, the prepare work for meeting open system arrival are also discussed.
This paper mainly introduces an OCR approach to eliminate the bar codes which have been prevailing in the automated circulation system of libraries. The disadvantatages of bar-coding project are also discussed in detail. In addition, the structure and functions of the OCR software system, the three scanning processes for character recognition and the test procedures and results are briefly described in the paper.
The paper analysis the practical significance as well as the present situation and problems in the use of machine-readable bibliographic data formats. It also explores the needs and possibility to develop a common conversion system mainly dealing with CCF. In addition, the development and trial run of such a system is briefly described in this paper.
