全分散式户外变电站自动化系统在变电站中的应用

通过对全分散式变电站自动化系统选型原则描述,说明微机保护监控装置装于户外端子箱上是完全可行的,以全分散式微机保护监控装置为基础全分散式户外变电站自动化系统是完全可行的。通过辽宁丹东电业局白云66kV变电所设备配置运行情况分析,证明全分散式户外变电站自动化系统,特别值得在城农网中推广应用,符合变电站向小型化发展方向。     

端子箱整治在变电站精益化管理中的实践

室外端子箱是变电站的重要设备之一,是动力、控制、测量和保护等电缆中转站、集线盒。近年来,因端子箱的缺陷引发事故,屡见不鲜,因此端子箱运维管理,也是保障电力设备安全运行的重要保障之一,更是精益化管理的体现。文章集结合近年来荆门地区变电站端子箱经常出现的凝露现象、端子短路、锈蚀等问题,提出了具体的标准化整治方案,并在各变电站中推广实行,取得了很好的效果。     

一种新型的端子箱和机构箱清扫工具研究

目前,变电站进行端子箱、机构箱清扫的普遍工具是抹布、毛刷,清扫过程有触电危险,而且工作效率低。因此,本文研究设计了一种适用于变电站端子箱、机构箱清扫的工具,以降低风险、提高清扫效率,满足变电站运行维护工作的迫切需求。     

变电站户外箱及开关柜智能除湿装置技术研究及装置加工测试

变电站的户外的机构箱的工作环境是比较艰苦的,容易出现露水,这对于整个的电力系统的设备运行有着非常大的安全方面的隐患。对于变电站的户外箱的露水产生的原因是费用有必要进行研究的。本文根据这种情况研究了关于智能除湿器的相关方法。     

变电站户外箱柜防潮分析及措施

对湖北地区500千伏变电站户外箱柜安装方式、箱体结构及驱潮装置的运行情况进行调研,分析户外箱柜受潮原因,在此基础上提出户外箱柜的设计选型、安装工艺、箱体改造及日常维护等相关要求。     

一起冻土引起的直流接地故障

变电站户外设备区地坪和地基处理的好坏直接关系到设备运行的稳定性和安全性,户外设备区地坪和地基的稳定性对其上的支撑物(砼杆、构支架等)直接产生影响。如果地坪和地基处理不好,轻则会发生砼杆、构支架倾斜,二次电缆线损坏;重则会发生倒杆引起电网事故或二次电缆线损坏引起的控制、保护系统误动作事故。因此,变电站户外设备区地坪和地基的处理现状不容忽视。     

变电站户外构支架腐蚀原因及防腐补强措施

早期建设的变电站,其户外构支架均为现场预制钢筋混凝土结构或预应力混凝土环形杆结构。由于混凝土自身结构特性及当年的技术水平和施工质量等原因,一般经多年运行使用后,普遍出现构支架表层混凝土有不同程度的开裂和剥落,钢筋腐蚀外露,连接埋件锈蚀脱落。对变电站户外构支架腐蚀进行研究和防腐补强设计处理己是当务之急,到了刻不容缓的地步。     

110kV沛县周庄变增容工程可行性研究

该变电站站址位于位于沛县龙固镇东北方,东,西邻龙固矿、氯碱厂龙固热电厂,临近后沙河村。该变电站与2008年投运,为户外常规变电站,110kV配电装置采用户外中型布置,架空由东进线,主变压器户外布置。     

完善保护屏顶小母线的绝缘措施

目前变电站都采用户外设计,尤其在面对西北地区风沙大的特点,不得不使运行人员对一次、二次设备每月进行清扫,确保变电站安全运行。保护屏顶小母线的稳定运行会直接影响到直流系统的安全运行,所以在小母线不可以停电的状态下进行带电工作。各个保护屏项小母线的大都采用实心裸露的铜棒,致使工作人员在运行的保护屏顶上工作,易发生触电危险及保护误动事故,影响了变电站的正常运行,经过有效绝缘实验和涮选决定引用双壁热收缩套管对裸露的小母线进行绝缘改进,有效地消除了工作人员带电工作触电隐患,确保变电站的正常运行。     

智能化变电站与传统变电站系统继电保护的比较

作为输配电系统的信息源和执行终端的变电站,其提供的信息量和实现的集成控制也会增加,所以一个简约的、智能的系统,实现信息共享,以提高运行、维护效率、减少投资成为目前的变电站的急切需求。未来的发展方向就是变电站自动化系统向智能变电站的发展。同时计算机应用技术和现代电子技术的迅猛发展,也使智能变电站离我们越来越近。目前已投运的智能化变电站广泛采用了IEC61850通讯规范和GOOSE网络及户外智能控制装置,继电保护在实现方式上做出了重大改革。     

Students' Reactions to the Introduction of Videoconferencing for Classroom Instruction

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.     

Cooler temperatures inductive to locust outbreaks

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.     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

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.     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

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.     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

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.     

Rough Justice: A Statistical Assessment of ICANN's Uniform Dispute Resolution Policy

Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP.     

Prevalence of soft neurological signs in Chinese people

Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.     

Monoculture Rubber Plantations Have Negative Ef ects on Controlling Splash Erosion

<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence     

Chinese Scientists Use Earth Observation Technologies to Study and Protect Wild Camels

<正>Chinese scientists plan to apply Earth Observation technologies to protect the critically endangered wild camels(Camelus ferus).With the help of remote sensing,satellite positioning,geographical information system and wireless sensors networks,they will be able to access the distribution and population of the wild camels and protect their habitats.The project will be carried out by the International Research Center for Wild Camel Conservation,which was jointly established earlier this year by the Institute of Remote Sensing and Digital Earth(RADI)of the Chinese     

More than Skin Deep – Understand Skin Biology by Means of Dermatogenomics

<正>The Paul Gerson Unna Research Group on Dermatogenomics was founded in October 2012 at the Partner Institute for Computational Biology.The ultimate goal of the group is to understand the biology of skin and skin appendages.