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1.
故障录波器装置在电力系统的使用愈来愈广泛,本文从故障录波器组成和原理进行分析,阐述了利用在线录波图形来帮助分析故障的准确性和快捷性,及使用过程中常见故障处理方法。通过在线录波装置在徐州电网的应用,为电力系统运行的稳定性、提高输电质量、缩短故障排除时间,提供了有力的保证。 相似文献
2.
电力系统的发展对变电站故障录波装置提出了更高的要求，计算机软硬件技术的飞速进步为微机型故障录波装置的性能改善提供了必要条件。本文介绍了一种基于当前先进的DSP技术的高性能的变电站故障录波装置的设计方案，分析说明了其软硬件结构和功能。 相似文献
3.
探讨分析了继电保护及故障信息管理系统在电网中的实际应用,阐述了继电保护及故障信息管理系统.该系统由主站系统与若干个子站系统有机组合形成,继电保护装置及故障录波器与子站系统联系,并通过子站系统转换协议,将有效数据上传至调度端用于事故分析;主站系统用于分析及管理其相关子站上传的数据报文,并集成了故障距离测定、阻抗数值分析、保护动作统计及故障录波数据分析等电力系统高级应用模块. 相似文献
4.
随着电力系统的发展,强机型保护和故障录波装置在系统中所占的比例日益加大,录取系统故障信息的能力也日益加强。继电保护故障信息分析处理系统的建立,实现了在电力系统发生故障后将完整的保护装置动作报告和录波报告迅速传送到省调及相关继电保护部门,使所有关心故障状况的人员（尤其是调度人员）能及时、准确地掌握电网的故障情况,提高事故的分析处理水平。同时,实现了保护人员在日常运行中对全网强机型保护和录波装置运行状况的动态、实时监测,大大提高了系统保护装置的健康运行水平。 相似文献
5.
本文从更换新型ZH-5故障录波装置入手,探讨了该装置的性能和特点,并讨论了如何利用故障录波装置提供的信息,来帮助分析判断系统发生何种故障,以及保护动作的是否正确。 相似文献
6.
智能电力系统故障录波仪是一种数据采集记录装置,它可以记录系统非正常和正常状况下系统电压、电流、频率的变化。在电力系统正常运行情况下记录的数据,对于分析电力系统正常运行下电能的应用情况起着重要的作用;而故障阶段记录的数据,对于分析电力系统故障发生的原因,以及帮助寻找故障发生点,从而迅速处理相关故障事故起着关键的作用。 相似文献
7.
本文讨论了WGL-6型故障录波器如何利用工控机高速性、可靠性性能，使用HIMEM5YS支持下的扩充存储器管理规范(XMS)来扩充内存，解决故障录波器由于长时间录波而产生的大批量数据高速灵活转存的方法。并介绍了它的程序实现，编制了一个可以访问DOS下64M或128M内存，且具有自动卸载功能的XMS类函数。在实时高速采样系统中,能够很好地满足应用要求。 相似文献
8.
故障录波器作为电力系统故障分析的一种重要工具,在事故调查、事故原因分析及事故处理后迅速恢复供电方面,发挥着不可替代的作用。本文从硬件和软件两方面阐述了WLB-2000型故障录波器的功能及特点,并用实例说明了WLB-2000型故障录波器在龙羊峡水电厂的应用效果。 相似文献
9.
随着人们生活水平的不断提高,电能已成为现代化生产的主要动力,它在国计民生中日益显示出举足轻重的作用.本文结合动态故障录波系统的开发,对动态故障录波系统故障检测技术和处理算法进行了深入研究.根据<220～500kV电力系统故障动态记录技术准则>所提出的判据标准,针对当前电力录波动态记录装置在分析处理算法的效率和精确度上的不足,深入研究了各种检测与故障分析算法,提出并实现了一种准确可靠的检测与处理算法,从而大大加快了检测处理工作效率,更能满足实时性要求.经过对算法性能的计算机仿真,取得了良好的效果.该算法已被成功应用在电力系统动态记录装置的开发中. 相似文献
10.
电力系统继电保护装置故障处理方法与分析 总被引：1，自引：0，他引：1
继电保护装置是电力系统的重要组成部分,对电力系统的安全有效运行、防止事故发生等起着决定性作用。随着电力系统的高速发展和计算机技术的进步,继电保护也有了进一步的发展。本文简单介绍电力系统继电保护装置,分析继电保护装置故障及处理方法。 相似文献
11.
A research group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol-a chemical found in the skins of red grapes in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said. 相似文献
12.
《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
13.
Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
14.
《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
15.
A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
16.
Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
17.
Active biological molecules functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery disease diagnosis therapy new nanodevice construction.…… 《中国科学院院刊(英文版)》2008,22(1):22-22
Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction. 相似文献
18.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
19.
Leah A. Lievrouw 《The Information Society》2000,16(2):155-159
This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment. 相似文献
20.
Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献