首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
文献半衰期与普赖斯指数之间的关系研究   总被引:2,自引:0,他引:2  
文献半衰期和普赖斯指数是用来测度文献老化速度的两个重要指标。文章从文献老化B—K方程出发,首次给出文献半衰期与普赖斯指数之间的关系式。用该关系式拟合了超导专业期刊的引文数据。计算结果表明:B—K方程的半衰期计算公式和莫蒂列夫修正式的半衰期计算公式对某些文献半衰期小于3年的学科(专业)是不适用的;新的计算引文半衰期公式所得到的结果与内插法得到的结果非常接近;并且该公式给出的半衰期范围围要比B—K方程的半衰期和莫蒂列夫修正式的半衰期要大得多。因此,新的计算引文半衰期公式更具普适性。  相似文献   

2.
计算机科学文献的老化速度   总被引:3,自引:0,他引:3  
王春霞 《晋图学刊》2004,(3):4-6,75
本文以计算机技术学科类具有代表性的10种期刊2001年发表的全部论文为统计对象,收集其引用文献进行该学科的文献老化研究。对该学科引文的时序分布、当年指标、最大引文年限、引文半衰期、普赖斯指数等文献老化量度指标进行统计分析。结果表明:该学科的中、外文文献最大引文年限分别为第3和第4年,引文半衰期为5.5年,普赖斯指数为45.8%,并提出分别以该学科中、外文文献发表后的11年和16年作为文献保存年限参考值,建议把该学科近5年内发表和出版的文献作为文献订购的时限。  相似文献   

3.
引文起飞是文献被广泛采纳的重要信号,引文起飞的分布规律研究对解释引文动态进程具有重要意义,为文献科学评价提供新视角。本研究以中国社会科学引文索引(Chinese Social Sciences Citation Index,CSSCI)数据库1998—2018年的引文数据为研究对象,在对引文起飞识别基础上进行统计分析、对比分析及分布模型拟合,较为全面地揭示了引文起飞分布规律。本研究发现,我国人文社会科学文献大多仅存在一次起飞现象,主要分布在发表后的0~3年,且首次被引往往伴随着引文起飞;引文起飞论文数比例分布符合指数分布规律,拟合系数β可以判断文献引文起飞分布的集中离散情况;不同学科引文起飞分布存在差异,不同被引频次的引文起飞指数分布模型进一步解释了文献被引的内在机制。引文起飞学科分布差异可为知识分类提供参考,本研究的相关结论也可为建立新的科学评价指标提供思路。  相似文献   

4.
基于数学、计算机科学、经济学和历史学四类学科期刊样本1980-2009年间发文量与被引量的统计数据,结合SPSS统计工具软件,分析4门学科期刊30年间文献增长的数量特征及其曲线拟合结果,并结合插值被引半衰期与B-K被引半衰期剖析两种文献老化测度指标之间的数量差异,以及两者共同反映出的科学文献老化趋势延缓与学科差异化特征。最后,基于上述分析结果定量化揭示影响文献老化的学科、文献增长、文献介质类型等外部因素及内在机理,以期对当前环境下科技期刊长期老化状况做一个全面客观的认识。  相似文献   

5.
我国主要石油科技期刊的引文分析与老化研究   总被引:3,自引:0,他引:3  
用引文分析方法研究了石油科技期刊文献的引文年代分布特征,探讨了石油科技期刊文献的老化规律,计算了老化半衰期等量度指标。  相似文献   

6.
使用抽样调查方法,以利用外文文献较多的人文社会科学重点学科为研究对象,通过对教师、硕、博士研究生的科研成果进行引文分析,研究高校人文社会科学教学科研人员的外文文献需求和信息利用行为模式,并与CASHL项目的馆藏情况进行比对,研究高校人文社科外文文献保障率,为构建我国高校人文社科外文文献资源保障体系提供理论支持。  相似文献   

7.
运用文献计量学中有关内容分析、作者分析、引文分析的一些基本方法,对贵州财经学院人文社会科学研究人员2000~2006年发表的期刊论文,从发文指标、引文指标、摘录指标三个方面进行了全面的统计、分析和评价,比较客观地揭示和描述了新世纪初贵州财经学院人文社会科学研究与发展的基本状况。  相似文献   

8.
科技文献老化过程的数学辨识模型   总被引:4,自引:0,他引:4  
分析研究了几种科技文献老化数学模型 ,讨论了引文年代分布数据统计中引文频次的采样误差。基于过程辨识理论 ,提出了科技文献老化的数学辨识模型 ,即传递函数模型。参考文献12。图 5。  相似文献   

9.
利用CSSCI对我国高等院校人文社科研究状况的分析   总被引:11,自引:0,他引:11  
据南京大学研制的《中文社会科学引文索引》(CSSCI)对全国各地区、各高校在人文社会科学各领域的发文情况的统计分析 ,可以了解全国人文社会科学发展概况 ,为人文社会科学研究的发展提供决策依据。参考文献 3。表 6。  相似文献   

10.
[目的/意义] 长效文献是指出版多年后仍然被连续多年引用,或者引用频次相对较高的文献,研究这部分老化较慢的长效文献的影响力,有助于完整评价文献整个生命周期的价值。[方法/过程] 选取CSSCI数据库来源期刊(2016-2017)中九个学科在2012年-2016年间出版期刊文献的引文年代数据,通过共时观察法进行科学文献老化情况和长效文献分析的研究。[结果/结论] 期刊中引文年代较为久远的引用量来自于大量的低频次被引用的文献集合。长效文献数量较少,可分为3种类型:成长型、成熟型和衰退型,3种类型的长效文献会随着时间推移产生一定转化。具有长效文献较多的期刊未必影响因子高,除心理学学科外,其他每个学科都有且仅有一本具有显著长效影响力的期刊。长效文献的关键词与当前学科研究热点相似,但是长效文献的追溯年代更久远,在反映当前学科热点来源的同时,对未来学科热点预测将发挥作用。  相似文献   

11.
This article surveys a sample of sources of the information about Romania available to British readers in nineteenth century British newspapers and periodicals. It traces first contacts between the Romanian lands and Britain after the union of the principalities of Wallachia and Moldavia in 1859, then after their independence from the Ottoman Empire. The article highlights an increased Romanian interest in British periodicals, which reported and reviewed Romanian literature and scholarship. The article concludes that nineteenth century British newspapers and periodicals offer a great variety and wealth of new material previously unavailable or unknown to researchers. It also states that only a portion of a large quantity of this material has been indexed and is therefore available via the bibliographic sources mentioned in the article. The author argues for the need of a new and updated British-Romanian bibliography, which can draw on new online resources offering access to thousands of new newspapers and periodical records.  相似文献   

12.
ABSTRACT

In today's current political environment raising support for millage renewals, bond campaigns or even millage continuations for public libraries is affected by national politics, and a tendency towards tax aversion on principle across the country. The lessons we can learn from the governing boards of small and rural public libraries are worth raising up to a greater national consciousness. Board governance, community consciousness, and facilities management are clear and logical tools that elected boards of public libraries can use to politick for support of libraries.  相似文献   

13.
ABSTRACT

The paper looks at library approval plans for material published in Slavic, East European, and Eurasian countries from the selector's point of view. Reasons why a selector would or would not want one are examined. Success with approval plans requires monitoring receipts, as well as good and ongoing communication among the selector, the acquistions department, and the vendor. A preliminary list of vendors offering approval plans for the countries of the region appears in the appendix.  相似文献   

14.
为进一步提升武汉科技信息共享服务平台使用效率,本文从平台资源建设、资源应用、供需对接方式和供需特点等方面分析了武汉科技信息资源服务现状;基于需求和利用的角度,结合平台管理实践和走访用户、问卷调查等研究方法,从信息资源需求主体和平台自身建设管理两个维度,找出制约科技资源供需对接的主要因素;以市场化和制度化为创新理念,从政策创新、机制创新、市场化服务、环境营造、人才培养等方面提出平台建设由“资源集聚”向“需求导向”转变的对策建议.  相似文献   

15.
ABSTRACT

The article examines the most important periodicals of ethnic minorities in Poland. After 1989, many ethnic groups (e.g., Germans and Romanies) were allowed to publish journals and newspapers for the first time since the end of World War II. The publications examined show the rich cultural life of the various ethnic groups as well as their current status in Poland. In addition to popular titles, some scholarly publications are also discussed.  相似文献   

16.
ABSTRACT

The history of the almanac in Croatia is reconstructed through primary research in bibliographic and archival sources. The almanac is a vehicle for knowledge communication in informal contexts, engaging both oral tradition and literary forms traceable to medieval literacy and ways of structuring knowledge. The history of the almanac in Croatia reflects the changing context of the book trade, literacy, and the evolution of language. Four main stages are identified: (1) the beginning of the annual almanac in the seventeenth century; astrological almanacs reflecting the sensibility of the Baroque period; (2) the Enlightenment's stimulation of almanac publishing in the spirit of contemporary secular reforms in agriculture and education; (3) nineteenth-and twentieth-century almanac trade, showing complex and overlapping networks for the production, distribution and appropriation of printed almanacs;(4) roughly the end of World War II, when the almanac slowly moved out of the role of a popular mass medium and into specialized niches represented by regional, diaspora, and religious almanacs.  相似文献   

17.
This essay investigates key moments in the history of personal digital assistant (PDA) marketing to women. Analyzing promotional texts for three PDAs that received considerable press coverage from 1999 to 2001, this essay explores the cultural significance of the convergence of anxieties about women's place in the gendered division of labor with the computer industry's changing marketing imperatives. Drawing on an array of promotional texts, including news articles, press releases, promotional Web sites, and ads appearing in newspapers and magazines, this paper tells the story of how the computer industry aimed to sell smaller, faster computing devices to women while promising to mediate and thus reproduce women's overwork as paid and familial laborers. After experimenting with the PDA as a sexy fashionable gadget for working women, marketers approached women as mothers with “Audrey,” an Internet appliance designed for the kitchen.  相似文献   

18.
This study explores the attitudes and actions of bank managers toward communication spending during recession. Results of this study indicate that organizational leaders cut communication spending early during recession and also erroneously rely on the bank's financials to mitigate irrational customer withdrawals. This research is used to illustrate the need for public librarians to meet the needs of bank stakeholders when their institution ceases to communicate during crises, for academic librarians to educate students in undergraduate and graduate programs regarding heightened information needs during recession, and for corporate librarians to understand a potential avenue for competitive advantage during recession.  相似文献   

19.
The author answers a reference question on bibliographic sources for the Ukrainian periodical press 1840–1850. Helpful publications include bibliographies, guides, and library catalogs. These potentially make mention of revolutionary developments in Hungary (such as the Twelve Points paragraph of the Demands of the Hungarian Nation in March 1848, the subsequent April Laws, and Hungary's declaration of independence in April 1949), and elsewhere in the Hapsburg Empire.  相似文献   

20.
Some key questions for publishers in today’s market are: Could Amazon’s recent merger and acquisitions strategy create a disruptive or paradigm shifting business model in the publishing industry? Do their recent actions post mergers and acquisitions illustrate a predicable pattern of behaviour that publishers can strategize around? This paper will explore these questions and look at some of the possible reasons behind Amazon’s business practices and the possible consequences to publishers.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号