共查询到20条相似文献，搜索用时 171 毫秒
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本文介绍了高等数学的近似计算方法中切线法和二分法的思想，再利用其思想结合C程序设计语言，编写出了求一元三次方程根的程序，该程序稍加修改，即可成为求更高次方程根的程序。 相似文献
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介绍了现行建筑给水排水设计规范规定的管道饮用净水系统配水管设计秒流量的计算方法,指出该方法在饮水水嘴使用概率计算上存在的问题。分析了造成这些问题的原因,用正态分布和泊松分布近似计算二项分布并利用大数定律和随机变量的函数关系,导出管道饮用净水设计秒流量的简化计算公式。 相似文献
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引文半衰期与普赖斯指数之间的数量关系研究 总被引：11，自引：0，他引：11
本文运用文献计量学方法,对SCIE收录的106种力学专业期刊文献所附的2869099条参考文献进行了分析,考察了力学专业领域引文半衰期和普赖斯指数之间的关系,并用同时法计算了引文半衰期和普赖斯指数,将引文半衰期和普赖斯指数进行了比较。研究结果表明,引文半衰期和普赖斯指数成反比变化,引文半衰期和普赖斯指数之间存在着简单的数量关系:P(4)*H=2(P为普赖斯指数,H为引文半衰期)。通过普赖斯指数P(4)可以简便地近似计算引文半衰期,并具有较高的精度。 相似文献
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综述了我国设施内土壤盐碱化的严峻现实。分析了土壤盐碱化的成因,并归纳了我国土壤盐碱化的类型,回顾了近年来中国盐碱土壤修复的历程和研究成果,归纳了盐碱土壤修复的方法,并且评述了其各自的特性,分析了各个修复方法的优点点,肯定了成绩,指出了不足。最后,对设施盐碱土壤的修复指明了正确的方向,并提出了较高的期望。 相似文献
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中国一线市场的市场熟了,消费者理性了,渠道丰富了,终端饱和了,竞争加剧了,中国企业的老板开始紧张了,都准备把营销战场从一线城市拉到更低的地方了,这才有了激情四射的二三线市场营销竞争新格局。 相似文献
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春天到了,百花竞放,西花厅的海棠花又盛开了.看花的主人已经走了,走了 12年了,离开了我们,他不再回来了.
你不是喜爱海棠花吗?解放初期你偶然看到这个海棠花盛开的院落,就爱上了海棠花,也就爱上了这个院落,选定这个院落,到这个盛开着海棠花的院落来居住.你住了整整26年,我比你住得还长,到现在已经是38年了. 相似文献
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新闻版上,领导的照片与活动少了,普通百姓成了主角;社会新闻增加了,可读性增强了,报纸版面多了,厚了,内容丰富了,有分量了[编者按] 相似文献
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在中国,图书馆员没有职业化,何来"去职业化"及研究?中国图书馆还没有进入"职业化"——法律的界定,"图书馆员去职业化"及研究是"非理性"的。然而,中国图书馆和图书馆员事实上的职业化是存在的,图书馆员职业是图书馆员赖以生存的物质来源、是图书馆员善心悦目的精神基石、是图书馆员朝夕相伴的职业港湾。业务外包是图书馆员去职业化的风险投资与不当支出,图书馆员"职业边缘化"及研究具有客观性,"图书馆员去职业化"及研究却是虚妄的。面对着中国图书馆职业"边缘化"的趋势和风险,应该推进图书馆员职业化,而图书馆员"去职业化"研究应该滞后。 相似文献
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针对目前学界存在的对文件连续体理论的一些误读,本文系统梳理和阐释了文件连续体理论的核心概念、产生背景、主要内容及其应用,指出文件连续体理论是在澳大利亚基于证据和连续体的文件管理思想、文件系列体系思想的基础上,借鉴后保管主义及结构化理论建构的后现代主义文件保管的新范式。它强调文件并非是中立物,文件的运动具有时空延伸性。该理论的终极诉求是建立一个自下而上的、可靠的文件保存体系,以完整保存集体记忆,促进社会民主发展。要实现这一诉求,文件的保存就需多方主体的参与和合作。文件连续体理论为文件管理提供了重要的理论框架,对建构完整的社会记忆具有重要的指导价值,同时也为对传统档案学的核心概念及理论进行批判性反思提供新的视角和工具。 相似文献
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Bill Kennedy 《Publishing Research Quarterly》2010,26(3):187-192
A concise review is presented of the essential elements of the book publishing and bookselling business in a complex and diverse
market. Demographics create the diversity while Arabic is the one language spoken across a multitude of different countries.
Three features are common to all of these countries and they are: the dominance of English as the second language, education
has and will remain to be a priority, and economic pressures cause price sensitivity to be a major challenge especially in
the educational market segments. It is the price sensitivity as a key factor for the lack of respect for intellectual property
and copyright regulations. A review of distribution and retail stores is a very important topic in relation to this complex
collection of countries. The emergence of e-books is discussed especially in the educational, professional and reference market
segments. Finally, there is a review of the Arabic language publishers and local book fairs to bring this article to closure. 相似文献
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John L. Sherry 《Journal of Applied Communication Research》2013,41(3):302-306
In communication science, the distinction between applied and basic research is often accompanied by a discussion of the relative value of each. However, the idea that there is a value distinction to be made between applied and basic research is fundamentally inconsistent with scientific epistemology. Rather than different modes of inquiry with different relative value, communication science is a whole, constituted by applied and basic researchers who focus on different goals of science: to explain, to predict, and to control. An example is provided of a highly successful communication intervention created via the cooperation between applied and basic scholars. 相似文献
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Adam Etkin 《Publishing Research Quarterly》2014,30(1):23-38
This paper will propose a new system that produces a metric that is an indicator of the level of peer review conducted prior to the publication of scholarly material. A mathematical algorithm which incorporates weighted values of the roles within the peer review process is created. The h-index, which is a value that “measures the productivity and impact of a scientist or scholar,” is also incorporated. Each round of review is weighted using the square root as later rounds of peer review are often less rigorous than earlier rounds. Once a paper is accepted the calculation is conducted and a “peer review evaluation” metric, or “Peer Review Evaluation Score” (pre-SCORE) is available. It is clear that such a metric would prove beneficial to all engaged parties (authors, publishers, readers, libraries). Authors will know that their work is being evaluated by a trustworthy publication and by experts in their field. Legitimate, ethical publishers will be recognized as such. Readers would have the ability to filter out material which was not properly vetted, and libraries/consortia would have further assurance that their limited funds are spent wisely. Future studies to see if there is a correlation between the pre-SCORE and Impact Factor or highly cited material is possible. The proposed metric would be one more tool available to aid in the discovery of quality published research. 相似文献
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《Journal of Informetrics》2022,16(4):101323
Engagement on social networks is a complex concept, in which many interconnected, difficult-to-assess components interact. It is precisely this complexity which motivated this work, which proposes a composite index as a tool to measure engagement. Using TOPSIS, a multicriteria method that bases its ranking on minimizing the distance to the ideal point and maximizing the distance to the anti-ideal, a mix of indicators based on two approaches is used: the tweet approach and the follower approach. The former reflects engagement based on user production, and the latter measures engagement by popularity. This index was applied to a group of Social Media Influencers and a general ranking was obtained, as well as a ranking by each approach to measuring engagement. A comparison of the rankings generated by the different approaches shows the suitability and pertinence of both, as it is confirmed that they measure different aspects, and that both are needed to offer a holistic view of the engagement generated by a user on Twitter; this is a new finding compared to prior studies, which only focused on one approach or the other. 相似文献
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引文分析是图书情报学的重要贡献.引文分析的局限性表现在三个方面:对伪引的难以控制、对漏引的难以确认和对引用动机的难以辩识.引文分析局限性的根源在于“唯引是举”.引文分析是以整部文献为单元的分析,而互文性分析是以一个文本内部的话语为单元的分析.引文分析是基于形式的表层分析,而互文性分析是基于内容的批评性分析.互文性分析的目的在于揭示文本话语隐含的文化、心理、政治意义.互文性分析中的互文性类型包括语句互文、字词互文、体裁互文、修辞互文等.图书情报学理论应该关注互文性分析.进行互文性分析,有利于拓宽和深化图书情报学理论,有利于加强图书情报学理论的社会影响力.互文性分析与内容分析之间有区别. 相似文献
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The authors of this article contend that politics is an integral part of public library leadership. Most of the work that public librarians do is designed to build citizenship knowledge and improve some aspect of social justice. Politics is a library imperative because a heavy percentage of institutional funding is tied to public funding, which is a major part of total library financial support. Political considerations, therefore, are a major concern in acquiring and retaining funding that will bring libraries and their constituents to a brighter future. 相似文献
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图书馆罚款的法律探讨 总被引：5，自引：2，他引：3
图书馆罚款具有合理性,是图书管理的必要手段,但是,根据我国现行法律,图书馆罚款没有法律依据,不具有合法性.在图书馆罚款中,图书馆与读者的关系不是合同关系,而是一种管理关系,因此,不能把罚款改为违约技金.我国法律应当赋予图书馆罚款权. 相似文献