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101.
102.
Anna Pettersson Ida Johansson Sara Wallin Markus Nordberg Henric
stmark 《Propellants, Explosives, Pyrotechnics》2009,34(4):297-306
Standoff identification of explosives at distances of up to 55 m has been performed by applying spontaneous Raman spectroscopy. This work has been focused on detection in a realistic environment, using an outdoors test field and performing experiments under varying weather conditions such as rain‐ or snowfall or bright sunshine. The instrumentation, based on a 532 nm pulsed laser source combined with gated detection, proved the performance insensitive to weather variations. Investigated HMEs and precursors were TATP, HMTD, HP, MEKP, NM, NB, and IPN; all in bulk quantities. The time needed for acquiring spectra was typically between single pulse (5 ns) and 10 s. Detection through green and brown glass bottles and PET bottles were tried and found viable. 相似文献
103.
在分析变电站智能电子设备远程配置的底层安全机制如IP层协议安全结构(IPSec)、安全套接层协议(SSL)等方法局限性的基础上,提出了一种基于可扩展标记语言安全(XML Security)的变电站远程配置安全机制.该机制定义了变电站配置描述语言(SCL)的安全扩展,通过XML数字签名实现配置文档的完整性和通信双方实体的身份认证;通过XML加密实现对配置文档的多粒度安全保护.为验证安全机制的有效性,设计了远程安全配置仿真系统.对变电站实例配置文件的安全处理结果显示,该方法能有效满足SCL配置过程中的安全需求. 相似文献
104.
105.
智能变电站开关柜综合状态监测IED设计 总被引:3,自引:0,他引:3
针对现代电力开关柜设计了一种基于物联网技术并符合变电站IEC61850标准的应用于变电站间了一种隔层的新型开关柜综合状态监测智能电子设备(IED)。该IED采用ARM+DSP双CPU架构为硬件核心,以VxWorks实时操作系统和C语言为软件开发平台,嵌入符合IEC61850标准的IED性能描述文件(ICD),解析IRIG-B码进行同步对时,通过ZigBee无线网络和RS485/RFID/CAN总线实现与开关柜在线监测装置(过程层)的数据传输,按照IEC61850标准规约用光纤与综合应用服务器(站控层)进行通信。此外,还完成了开关柜综合状态监测系统结构设计、IED硬件电路设计、软件平台的构建以及IEC61850的信息建模。实际运行结果表明,该开关柜综合状态监测系统能够远程对所有开关柜状态进行综合采集、分析、传输与监测,并将这些功能融合到一体化住处平台诊断中。 相似文献
106.
变电站在线监测智能电子设备(IED)通过IEC 61850标准通信方式采集并上传一次设备的状态信息到综合应用服务器等站控层装置,是变电站一体化监控系统的重要组成部分,对其进行功能测试是保证系统正常运行的基础。文中通过分析在线监测IED的功能,设计其功能测试用例,通过自动化测试脚本以及测试引擎,代替手动测试,提高测试效率。通过研制的在线监测IED自动化测试系统,以油中溶解气体监测数据上传功能为例,进行了自动化测试实验,并给出了测试流程及测试结果,验证了该方法的正确性和可行性。 相似文献
107.
A study on the development of in-process dressing lapping wheel and its evaluation of machining characteristics 总被引:5,自引:0,他引:5
J.-D. Kim E.-S. Lee J.-Y. Choi 《The International Journal of Advanced Manufacturing Technology》2005,26(3):211-218
Ceramics, carbide, and ferrite are widely used due to their significant mechanical properties such as light weight, chemical stability, super wear resistance, and electronics. Despite these characteristics, this material is not widely used for its difficulty in machining material. Therefore, the method of using a metal bonded wheel was proposed. However, a metal bonded wheel is difficult to dress. Recently, a new technology is being developed for In-Process Electrolytic Dressing to solve this problem. This technology provides dressing for metal-bonded wheels during the lapping process for in-process lapping of protruding abrasive from super-abrasive wheels. This method requires a wheel for electrolytic dressing, a power supply, and an electrolyte. A cast iron bonded diamond (CIB-D) wheel is dressed by electrolytic dressing and its electrolytic characteristics are evaluated. This study produced an ultra-precision lapping machine for in-process electrolytic dressing using super-abrasive CIB-D applied for lapping ceramics, sintered carbide, and optical glass. 相似文献
108.
微机保护、测控等智能装置是电力系统的重要组成部分。介绍了自动化测试及仿真测试环境的概念和基于此基础上的智能装置通用自动化测试系统。该系统采用分布式体系结构,模拟装置运行环境;采用脚本技术,可实现自动化的回归测试;采用开放式结构,方便系统扩展。实际应用表明,该系统可提高电力系统智能装置的测试质量及效率。 相似文献
109.
110.
M. García-GraciaS. Borroy L. Giménez de UrtasunM.P. Comech 《Electric Power Systems Research》2011,81(12):2178-2187
The new international standard for communication networks and systems in substations, IEC61850, is expected to involve a profound evolution in electrical power systems. The new functionalities supported by an intelligent application of IEC61850 must result in a significant improvement of stability and reliability of power systems.Protection systems play a leading role in power system stability and reliability, since those depend on correct, rapid and selective disturbances elimination. A new protection scheme, performed by new intelligent electronic devices (IEDs) based on the new features brought by IEC61850, is presented in this paper. The implementation of the proposed scheme involves important cost reductions, at the same time that the protective redundancy of the system is improved. 相似文献