高频词与低频词的界分及词频估算法

Mr. J.C. Donohue, in 1973, believe that there was a critical value in the demarcation of high-and low-frequency terms used in articles, and at the same time he proposed formulas of calculation. On the basis of adopting maximum value to determine grades of terms, this article brings forth and introduces a new formula of demarcating the high-and low-frequency terms which is not only simple and direct in the process of calculation but also more practical as compared with that of Mr. Donohue. Having made a study of ways of calculating for various kinds of terms with similar frequency,the article also gives a formula of calculation and reveals the inheret law governing the number of frequency of terms ans terms with similar frequency.The author holds that the frequency of terms appeared in the article and the number of terms with similar frequency have something to do with the number of different terms but have nothing to do with the length of the articles.10 formulas.5 tables.4 references.     

开端式学习环境研究

开端式学习环境（0pen—endedlearning environments）是一种以学习者为中心、以技术为支撑的学习环境。介绍了开端式学习环境的4个组成部分，阐述了开端式学习环境的特点，分析了开端式学习环境面临的问题。     

几个重要命题的条件极值法证明

就代数方面和几何方面几个常见重要命题用数学分析中的条件极值方法予以证明.     

CAJ-CD对高校图书馆的影响

分析了中国学术期刊(光盘版)(CAJ—CD)的特点，它对高校图书馆期刊工作、用户教育、参考咨询、电子化以及人员素质的影响.     

新发现的普9美术邮资封长加盖版式及特征

《集邮》1986年第5期,赵人龙发表《新中国第一套美术邮资封》,首次介绍普9型美术邮资封第二组,即编号6-1957至10-1957的5种封,背面均有"长加盖"的涂盖加印版式。《集邮》1997年第11期,瞿百顺《普9美术邮资封版式研究》一文提出,在上     

M5350计算机数控系统

本文分析研究了M5350数控系统的功能特点,对其技术经济效果进行了举证.     

新年趣题

值此2000年新年到来之际，我们刊出一组欢庆2000年的新年趣题．这些趣题，构思精巧，寓意深刘，饶有兴趣．特别是，有些趣题融入了本刊的某些数字特征，表达了广大读的欢庆心情和对本刊的美好祝愿．借此机会，本刊编辑部全体工作人员向广大读、作拜年，恭祝大家在新的一年里身体健康，万     

美国中文文献书目控制自动化述评

According to the statistical data of 1991, there are over a hundred libraries in North America holding a total of more than ten million Chinese, Japanese and Korean materials, among which there are 50%-80% Chinese records. The initial study made by the United States of bibliographic control of Chinese material dates from the last decade. Among the departments that made the study, the RLIN (Research Library Information Network) and the OCLC (On-Line Computer Library Center) are the two systems of uttermost importance.The paper reviews the development and the progress of the automation of bibligraphic control for Chinese materials in the United States and the five focuses already discussed.9 illus.1 table.1 appendix.25 references.     

课本及其延伸

文章以延伸为途径,就如何充分挖掘课本知识的内涵,走“科学主义—人文主义”相整合的课本研究之路进行了探讨。