水中测量接地电阻的探讨和实验

简述三极法通过土壤形成电流回路测量接地电阻的原理;探讨三极法在水中测量接地电阻的可行性;对有代表性水域的接地电阻采用比较法进行实地测量;通过方差分析和相关系数分析方法探讨三极法在水中测量接地电阻的适用性和有效性。     

道路照明配电系统接地方式和线路保护的探讨

探讨了城市道路照明配电系统的接地方式和配电线路的保护.分析了城市道路照明采用TN-S接地方式时,接地故障保护存在的问题.提出:城市道路照明配电系统应采用TT接地方式;若城市道路照明线路不很长,可有条件地采用TN-S接地方式;城市道路照明严禁采用TN-C接地方式;采用TT接地方式和漏电保护时,漏电保护的动作电流应大于正常泄漏电流的2.5～3倍,宜整定为100～500 mA.     

Socially augmented argumentation tools: Rationale,design and evaluation of a debate dashboard

Collaborative Computer-Supported Argument Visualization (CCSAV) is a technical methodology that offers support for online collective deliberation over complex dilemmas. As compared with more traditional conversational technologies, like wikis and forums, CCSAV is designed to promote more critical thinking and evidence-based reasoning, by using representations that highlight conceptual relationships between contributions, and through computational analytics that assess the structural integrity of the network. However, to date, CCSAV tools have achieved adoption primarily in small-scale educational contexts, and only to a limited degree in real world applications. We hypothesise that by reifying conversations as logical maps to address the shortcomings of chronological streams, CCSAV tools underestimate the importance of participation and interaction in enhancing collaborative knowledge-building. We argue, therefore, that CCSAV platforms should be socially augmented in order to improve their mediation capability. Drawing on Clark and Brennan influential Common Ground theory, we designed a Debate Dashboard, which augmented a CCSAV tool with a set of widgets that deliver meta-information about participants and the interaction process. An empirical study simulating a moderately sized collective deliberation scenario provides evidence that this experimental version outperformed the control version on a range of indicators, including usability, mutual understanding, quality of perceived collaboration, and accuracy of individual decisions. No evidence was found that the addition of the Debate Dashboard impeded the quality of the argumentation or the richness of content.     

加油站电气设计

针对汽车加油站存在爆炸危险区域这一特殊性,详细介绍汽车加油站爆炸危险区域的划分,提出了固定式可燃气体报警器、液位控制显示器、加油机的电气示意图,详细地阐述了加油站的照明设计及防雷、接地系统设计,具有一定的参考价值。     

高速公路电子系统雷电电磁脉冲防护

主要针对雷电电磁脉冲对高速公路电子系统造成的巨大危害,从影响的方式和途径入手,提出雷电电磁脉冲防护的要求以及相应的防雷接地方案     

一场电气火灾惨剧带给设计人员的警示

依据GB 50054-95《低压配电设计规范》有关短路保护、过负荷保护、接地故障保护的规定,对2009年＂11·27＂上海市浦东新区杨高南路2885号电气火灾案例进行事故原因分析,由该电气火灾惨剧带来的警示,提出必须严格按照国家强制性标准正确、有效地进行电气设计。     

应重视计算和测量接地故障回路阻抗

《低压配电设计规范》中有对接地故障回路阻抗进行计算的规定．但至今没有得到广泛的重视和执行。由于这条规定涉及人身安全．作者希望我国电气工程设计界和施工界的同仁们．能够重视对TN系统的接地故障回路阻抗进行计算和测量．     

舰船岸电低压配电系统接地型式分析

舰船停靠码头后需要由岸上的电力系统为其供电．舰船上低压配电系统接地型式大多采用电源中性点不接地的IT系统．而陆地上民用低压配电系统的接地型式采用电源中性点直接接地的TN或TT系统。对于同一个低压配电系统．当船电和岸电电源中性点接地方式不同时．系统接地型式发生了改变。通过对引接岸电电源的舰船低压配电系统接地型式比较、分析...     

谈谈综合医院的配电设计

本文依据相关规范要求及实际的工程设计,对综合医院的电源配置、配电系统的设计、接地与安全及手术室的配电进行分析与论述.提出了要充分考虑医疗场所用电的特殊性,合理配置电源,采用双干线配电方式与放射式配电方式相结合的配电系统以及相适应的接地与安全设计.     

35kV、110kV建筑变电所设计的几个问题

简要介绍10～110kV建筑变电所的新设备及新技术,详细介绍10～35kV低电阻接地系统接地电阻的选择、接地故障保护的设置与整定。