广西电大远程教育网络系统改造与应用设想     

何一辉 《广西广播电视大学学报》2004,(4)

网络发展日新月异,网络上的新设备、新技术、新应用层出不穷,出现了许多新的组网方式。电大网络的数据量、用户量和访问量的迅速增大,对网络技术和网络平台提出了更高的要求。广西电大原有的组网方式太复杂,维护困难,运行成本高。因此,在体现其低资费、高效率和电大可持续发展的前提下,必须对电大网络进行重新构建。本文主要阐述全区电大网络改建和应用的初步设想。  相似文献   

一种基于双控节点的Ceph写性能优化方法     

黄遵祥  朱磊基  熊勇 《中国科学院大学学报》2022,39(6):817-826

分布式存储系统Ceph由于采用多副本强一致性写入机制,造成集群写性能不理想。针对该问题,提出一种基于双控节点的Ceph写性能优化方法,首先利用双控双存储阵列节点,当一个控制器出现故障时,该节点中的另一个伙伴控制器创建新的OSD进程并快速接管故障控制器的存储阵列,从而保证数据存储的安全性和高可靠性,同时将写入机制优化为主副本OSD在本地写入日志盘后,就向客户端返回写完成,之后写入数据盘和其余从副本的完成情况则由主副本OSD继续收集并完成后续各类回调操作,从而降低非必要写操作对集群写性能的影响。最后对数据可用性和集群写性能进行实验测试,其中写性能测试分别从写延迟、吞吐量和IOPS等3个角度,对优化后的方法和Ceph原生写入机制在顺序写和随机写两方面进行比较,进一步验证优化方法在维护数据高可用的同时,对写性能提升的效果。  相似文献   

论数字馆藏的评价   总被引：5，自引：0，他引：5  

宋迎迎 《图书情报知识》2006,(5):19-22

本文首先对数字馆藏的概念及构成重新作了分析,指出数字馆藏评价包括对馆藏数字资源和数字资源存储系统的评价,而对馆藏数字资源的评价又包括对数据库、网络资源导航和其它数字化文献的评价。进而对数字馆藏存储系统的评价进行了系统的论述。  相似文献   

当前出版印刷业对图书馆工作的影响   总被引：3，自引：0，他引：3  

邓友诚 《重庆图情研究》2006,7(1):17-18

本文以笔者自己的切身体会，阐述了当前出版印刷行业的一些新情况、新变化对图书馆采编以及图书保护工作的影响，并提出了相应的解决办法。  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   

基于内容管理的数字图书馆模型探讨   总被引：5，自引：0，他引：5  

谌群芳 《图书情报工作》2005,49(2):35-38

简要描述内容管理技术的概念及功能,提出将内容管理引入数字图书馆中,构建基于内容管理的数字图书馆模型,并重点论述该模型的主要组成部分,包括4个业务系统(收集系统、管理系统、发布系统、工作流系统)和两个存储系统(元数据仓储系统、内客存储系统)。  相似文献   

Seeking Nettle Textiles – Utilizing a Combination of Microscopic Methods for Fibre Identification     

Jenni A. Suomela  Krista Vajanto  Riikka Räisänen 《文物保护研究》2018,63(7):412-422

Bast fibres have been commonly used as a textile material in Northern Europe since Neolithic times. However, the process of identifying the different species has been problematic, and many important questions related to their cultural history are still unanswered. For example, a modified Herzog test and the presence of calcium oxalate crystals have both been used in identification. In order to generate more reliable results, further research and advancement in multi-methodological methods is required. This paper introduces a combination of methods which can be used to identify and distinguish flax (Linum usitatissimum), hemp (Cannabis sativa), and stinging nettle (Urtica dioica). The research material consisted of reference fibres and 25 fibre samples obtained from 12 textiles assumed to be made of nettle. The textiles were from the Finno-Ugric and Historical Collections of The National Museum of Finland. The fibre samples were studied by observing the surface characteristics and cross sections with transmitted light microscopy, and by using a modified Herzog test with polarized light, in order to identify the distinguishable features in their morphological structures. The study showed that five out of 25 samples were cotton, 16 nettle, one flax, and one hemp. Findings from two samples were inconsistent. The results show that it is possible to distinguish common north European bast fibres from each other by using a combination of microscopic methods. Furthermore, by utilizing these combined methods, new and more reliable information could be obtained from historical ethnographic textiles, which creates new vistas for the interpretation of their cultural history.  相似文献   

Wearable skin-like optoelectronic systems with suppression of motion artifacts for cuff-less continuous blood pressure monitor     

Haicheng Li  Yinji Ma  Ziwei Liang  Zhouheng Wang  Yu Cao  Yuan Xu  Hua Zhou  Bingwei Lu  Ying Chen  Zhiyuan Han  Shisheng Cai  Xue Feng 《国家科学评论(英文版)》2020,7(5):849

According to the statistics of the World Health Organization, an estimated 17.9 million people die from cardiovascular diseases each year, representing 31% of all global deaths. Continuous non-invasive arterial pressure (CNAP) is essential for the management of cardiovascular diseases. However, it is difficult to achieve long-term CNAP monitoring with the daily use of current devices due to irritation of the skin as well as the lack of motion artifacts suppression. Here, we report a high-performance skin-like optoelectronic system integrated with ultra-thin flexible circuits to monitor CNAP. We introduce a theoretical model via the virtual work principle for predicting the precise blood pressure and suppressing motion artifacts, and propose optical difference in the frequency domain for stable optical measurements in terms of skin-like devices. We compare the results with the blood pressure acquired by invasive (intra-arterial) blood pressure monitoring for >1500 min in total on 44 subjects in an intensive care unit. The maximum absolute errors of diastolic and systolic blood pressure were ±7/±10 mm Hg, respectively, in immobilized, and ±10/±14 mm Hg, respectively, in walking scenarios. These strategies provide advanced blood pressure monitoring techniques, which would directly address an unmet clinical need or daily use for a highly vulnerable population.  相似文献   

利用SAN技术实现视频流应用中的海量信息存储     

茹宏丽  张建伟 《唐山师范学院学报》2006,28(2):91-92

提出了通过建立SAN存储区域网和磁盘阵列来实现海量存储的设计思路。  相似文献   

关于专升本高校图书馆馆藏建设的问题   总被引：2，自引：0，他引：2  

张灵霞 《商丘职业技术学院学报》2004,3(2):59-61

高校专升本后，图书馆馆藏文献存在着数量严重不足，质量较低，结构不合理的实出矛盾加强馆藏建设是高校为社会提供信息服务的重要基础确立科学、正确的馆藏指导思想，增加文献购量的投资力度，实现信息资源共享，突出馆藏特色，提高馆藏质量，是解决这一矛盾的重要途径。  相似文献