数字对象的存储与传输   总被引：7，自引：1，他引：6  

朱先忠  孙一钢  张洪亮 《现代图书情报技术》2002,18(1):6-8

数字对象按被使用时的表现形态可分为四大类:静态文档对象、流媒体对象、复合数字对象和交互式对象,不同的数字对象对应着不同的传输形式,这一特点决定了数字对象需要不同类型的服务器;在对象服务器内部 ,数字对象的命名体系和寻址方式决定了服务器的可维护性和可扩充性,文章给出了一个零维护解决方案;数字对象的打包和传输方式影响着客户的使用质量和为此付出的成本,本文同时给出了一个文档对象的打包形式和传输方式;最后说明了一个数字对象服务器的实现  相似文献   

图书馆应重视古旧书报刊收藏--兼谈《中国古旧书报收藏交流指南》     

许馨 《图书馆建设》2006,(1):105-106,109

针对高校图书馆古旧书报刊流失损耗的问题，提出高校图书馆、公共图书馆应该重视古旧书报刊收藏。请有关领导给予经济、人力支持；并愿图书馆从业人员增强古旧书报刊的收藏意识，学习古、旧书报刊收藏知识。  相似文献   

数字图书馆网络存储模式评析     

徐迈 《图书馆学研究》2006,(9):25-27

本文介绍了目前主要的存储体系结构，分析了各种体系结构的主要特点和适用环境，并对数字图书馆的存储发展趋势作了一些探讨。  相似文献   

如何提高数字图书馆设备的采购质量     

李振钱 《图书馆杂志》2004,23(12):36-38

本文从设备的先进性与实用性、经济性之间的关系，考虑设备的安全性、稳定性和可靠性，准备招投标文件和保证设备的质量、可维护性等方面论述了如何提高数字图书馆设备的采购质量。  相似文献   

网络存储领域内的核心技术——iSCSI   总被引：9，自引：0，他引：9  

吉炽平 《现代图书情报技术》2004,20(6):46-48

数据的异地实时存储日趋增多使得网络存储技术日渐重要。iSCSI 作为网络存储的核心技术充分利用了现有IP 网络的成熟性和普及性优势, 对经济合理以及便于管理的存储设备提供了直接访问的能力, 其低廉、便捷、开放、安全、标准等众多优异品质在未来必将得到充分的完善与发展。  相似文献   

Exertional heat illness risk factors and physiological responses of youth football players     

Susan W. Yeargin  John J. Dickinson  Dawn M. Emerson  Jessica Koller  Toni M. Torres-McGehee  Zachary Y. Kerr 《运动与健康科学(英文)》2021,10(1):91

  相似文献   

Understanding storage environmental stability during power outages: A key issue in sub-tropical climates     

Edward Kinfai Tse 《文物保护研究》2016,61(1):31-36

Efficient air-conditioning systems facilitate climate control in modern museums, libraries, and archives. The climate in Hong Kong is typically hot and humid, so the survival of collections is highly dependent on 24-hour air-conditioning systems to maintain the desired environment in repositories of archives and books, or artefact stores. The continuous operation of such systems in turn relies on a number of factors, such as uninterrupted electricity supply, an active maintenance programme, daily monitoring of their performance and quick response to irregularities as well as backup or alternative systems to support the air-conditioning load in case they are down for servicing. From the risk management point of view, unlike the latter four factors, electricity supply is an external factor that cannot be guaranteed. Fluctuation in the power level that results in stoppage of air-conditioning equipment is not uncommon even in well-developed countries. Long power outages could be catastrophic as they might lead to irreversible damage to collection items as a result of fast, large, changes in temperature and relative humidity (RH) towards the external environment if the air-tightness or hygrothermal stability of the storage are not good enough. Understanding storage environmental stability, especially during electrical power disruptions, is an essential part of the preservation measures and disaster preparedness necessary to protect valuable collections in cultural heritage institutions in the region.  相似文献   

Comparison of three web-scale discovery services for health sciences research     

Rosie Hanneke  Kelly K. O'Brien 《Journal of the Medical Library Association》2016,104(2):109-117

Objective

The purpose of this study was to investigate the relative effectiveness of three web-scale discovery (WSD) tools in answering health sciences search queries.

Methods

Simple keyword searches, based on topics from six health sciences disciplines, were run at multiple real-world implementations of EBSCO Discovery Service (EDS), Ex Libris''s Primo, and ProQuest''s Summon. Each WSD tool was evaluated in its ability to retrieve relevant results and in its coverage of MEDLINE content.

Results

All WSD tools returned between 50%–60% relevant results. Primo returned a higher number of duplicate results than the other 2 WSD products. Summon results were more relevant when search terms were automatically mapped to controlled vocabulary. EDS indexed the largest number of MEDLINE citations, followed closely by Summon. Additionally, keyword searches in all 3 WSD tools retrieved relevant material that was not found with precision (Medical Subject Headings) searches in MEDLINE.

Conclusions

None of the 3 WSD products studied was overwhelmingly more effective in returning relevant results. While difficult to place the figure of 50%–60% relevance in context, it implies a strong likelihood that the average user would be able to find satisfactory sources on the first page of search results using a rudimentary keyword search. The discovery of additional relevant material beyond that retrieved from MEDLINE indicates WSD tools'' value as a supplement to traditional resources for health sciences researchers.  相似文献   

热休克蛋白7O在乳腺癌和胃癌中的表达及其意义的研究     

程毅 魏贵亮周宁  吴迎爽谢震 祁贺薄爱华  张晓立邢立强 《河北北方学院学报(医学版)》2005,22(5):23-24

目的：探讨热休克蛋白70（HSP70）在人乳腺癌和胃癌中的表达及其意义。方法：应用免疫组织化学的方法对64例乳腺癌和55例胃癌组织中的HSP70进行检测。结果：（1）HSP70在乳腺癌和胃癌组织中的表达分别为78．13％．61.82％。（2）乳腺癌中HSP70的表达与乳腺癌的病理类型．淋巴结转移情况及年龄未发现显著差异（P〉0．05）。（3）胃癌中HSP70的表达与肿瘤浸润深度、淋巴结转移有密切关系（P〈0．05）。结论：HSP70在乳腺癌和胃癌中均呈较高水平表达．其中在胃癌中的表达与肿瘤浸润深度、恶性程度有密切关系,HSP70在乳腺癌和胃癌的发生发展中起重要作用。HSP70可能成为乳腺癌，胃癌的诊断指标之一。  相似文献   

Three dimensional couette flow and heat transfer through a porous medium with variable permeability     

Chaudhary?R.?C.?Email author  Sharma?Pawan?Kumar 《浙江大学学报(A卷英文版)》2003,4(2):181-185

This paper reports research on the effects of variations in injection velocity and permeability on the heat transfer and flow through a highly porous medium between two horizontal parallel plates situated at constant distance with constant suction by the upper plate. Due to this type of variation in injection velocity and in permeability the flow becomes three dimensional. The governing equations are solved by adopting complex variable notations to obtain the expressions for the velocity and temperature field. The skin-friction along the main flow direction and rate of heat transfer are discussed with the help of graphs.  相似文献