基于经济电流的低压电缆选型研究     

李明  孙晶晶 《黑龙江科技信息》2015,(6)

低压电缆截面可从技术和经济条件进行选型。以经济截面选型为理论基础,论述了按经济电流选择低压电缆截面的经济电流方法,并结合工程案例,剖析了有关参数变化对电缆经济电流选型中运行经济效益的影响。有利于工程技术人员根据工程项目的特点,合理选择相关参数,选取相对最优的经济电缆截面,从而可起到节约资源、保护环境的作用。  相似文献   

教学设计中教师自身因素对媒体选择的影响     

刘刚  马德俊 《现代教育技术》2010,20(8):70-74

文章从影响教学媒体选择的因素和选择的依据入手,对教学媒体选择的现状进行分析研究,揭示出其中存在的问题:对教师自身影响因素这个盲点的忽视,使得教学媒体的选择有失合理性。因此,作者结合系统论的观点,将影响教学媒体选择的因素纳入到系统中加以考虑,构建出了一个新的教学媒体选择影响因素模型图,并对影响教学媒体选择的教师自身因素进行了浅析,以期使教学媒体的选择更加趋于合理,更有利于教学效果的提高!  相似文献   

中华医学会信息管理平台——选稿系统的搭建与应用     

李君  顾佳 《中国科技信息》2012,(3):76-77

《英国医学杂志中文版》借助中华医学会杂志社创建的中华医学会信息管理平台—选稿系统向编辑自动化和办公无纸化过渡,提高了工作效率,做到了快捷、规范的编辑工作。选稿系统的建立为翻译类期刊网上办公做一借鉴。  相似文献   

The unsustainable directionality of innovation - The example of the broadband transition     

Inge Røpke 《Research Policy》2012,41(9):1631-1642

Information and communication technology (ICT) can be seen as a general-purpose technology with wide-ranging socio-economic and environmental implications across sectors. ICTs also constitute a system of technologies with stronger internal links since the emergence of the Internet and broadband as a new information infrastructure. The new infrastructure has co-evolved with widespread integration of ICTs in everyday life, and consumer demand has been decisive for ICT innovation. This article explores the environmental directionality of ICT innovation and the broadband transition, focusing mainly on energy impacts. It is argued that much innovation tends to develop in an unsustainable direction and that public regulation falls far short of the challenge. Transition theory is applied to analyze the background for the unsustainable development and the reasons why environmental concerns do not figure more prominently in the broadband transition. Finally, it is discussed how the direction of ICT innovation could be influenced in order to realize more of the positive sustainability potential.  相似文献   

Who uses a means-tested scholarship,and what do they choose?     

David Figlio  Cassandra M.D. Hart  Molly Metzger 《Economics of Education Review》2010

This paper provides detailed evidence regarding the nature of selection into a school voucher system. We use micro-data on scholarship applications matched with state student-level records on test scores, schools attended, and demographic background characteristics to describe the attributes of students who choose to participate in Florida's Corporate Tax Credit Scholarship Program, a means-tested scholarship program that is the largest of its type in the United States. We find evidence that those who choose to participate in the program tend to be lower-performing students from poorly performing schools, and that students of different backgrounds tend to choose different types of private schools. Students participating in the program tend to select schools that have more white students and fewer minority students, regardless of student race.  相似文献   

从游泳运动员中选拔铁人三项优秀运动人才的可行性研究     

林燕青 《福建体育科技》2009,28(2):38-40

本文探讨从游泳运动员中选拔铁人三项优秀运动人才的可行性，分析认为从游泳运动员中选拔铁人三项优秀运动人才是目前我国铁人三项优秀运动员的选材工作较为快捷的一秤方式。  相似文献   

Toward a theory of collection development: an activities and attributes approach     

William B. Edgar   《Library Collections, Acquisitions, and Technical Services》2004,27(4):393-423

This paper presents results of a study of corporate library selection activity performed to support four global corporations. The firms examined are involved in providing communication, knowledge in its different forms, and computing. Using these results, this paper synthesizes literature on selection and collection development to present an approach to developing an eventual theory of collection development. Using this approach, such a theory would predict the performance of selection activity; the operation of its attributes, such as its cost, centralization, and formalization; and the operation of other collection development activities. Concurrently, it would explain these predictions using dynamics such as the need to include specified ideas within selected content, the need to cope with selector's abilities to choose vast amounts of content, the need to contain selection cost, and the need to gather material together so as to support browsing and its resulting impromptu development of ideas.  相似文献   

电子资源评价与选择的几个问题   总被引：1，自引：1，他引：0  

强自力 《大学图书馆学报》2008,26(1):28-31

探讨了电子资源评价与选择中的几个理论问题。论述了评价和选择的区别,指出应重点研究制定选择标准。分析了制定标准的三种方式。探讨了传统评价标准与电子资源评价标准的异同。论述了不同类型电子资源评价与选择的特点。  相似文献   

高校外文图书采选与利用   总被引：2，自引：0，他引：2  

李煦  张莉 《高校图书馆工作》2007,27(5):31-32,45

笔者针对高校图书馆外文图书采选不足与利用"富余"矛盾的现象,提出了解决问题的措施.参考文献2.  相似文献   

摔跤运动员早期选材     

张云保 《武汉体育学院学报》2000,34(1):86-88

综述了摔跤选材的遗传学、生物学、生理学、心理学指标及依据。  相似文献