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在当前我国电网调度与运行管理系统中,SVG可以使用浏览器直接查看,可作为Web发布实时监视的图形。本文为此首先阐述了SVG的含义与优势,接着论述了电网调度的要求与SVG设计特点,重点探讨了基于SVG的电网企业调度与运行管理系统的要求,并通过实例分析了其实现过程与效果。 相似文献
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基于对航空可靠性、安全性和经济性方面的需求,对航空电气设备的故障预测与健康管理技术越来越多地得到了重视与应用,在国外的航空设备检测技术中,故障检测与健康管理技术已经成为了核心技术.介绍了航空电气设备故障预测与健康管理(PHM)技术,针对航空典型电气设备的故障预测与健康管理系统建模的重点内容,分析了航空电气设备的故障预测与健康管理技术的整体预测过程、相应应用策略. 相似文献
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胡瑞才 《电气电子教学学报》2005,27(6):32-33
以容抗为例回顾了电抗的定义与实质,指出了容抗与电阻不同,容抗是电容的电压与电流的有效值(或幅值)之比,而不是电压与电流的瞬时值之比。文章着重指出了在激励频率为定值时,给定电容的容抗为常数,而其u(t)/i(t)却是时间的正切函数。该文指出了电阻与电抗、阻抗的区别,对正确理解和使用阻抗有帮助。 相似文献
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晋察冀边区是中共创建的第一块抗日模范根据地,在这块红色的土地上,边区政府结合当时情况开展了轰轰烈烈的科普教育,形成了科普教育与政治教育、与战争需要、与多种传媒、与农业生产、与百姓生活、与学校教育、与职业教育以及与社会教育紧密结合的鲜明特点,创造了中国近代科普教育的辉煌。 相似文献
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基于B/S架构的数据挖掘原型系统的设计与实现 总被引:1,自引:0,他引:1
对C/S架构与B/S架构的基本概念与优劣进行了介绍与比较,提出了一个基于B/S架构的数据挖掘原型系统.然后介绍了该系统的需求分析、总体设计与技术路线,展示了系统实现界面,并着重介绍了关联规则算法在本系统中的实现. 相似文献
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一种基于DSP的语音录放系统的设计 总被引:3,自引:0,他引:3
文章介绍了TMS32 0C5 4x与PC组成的语音录放系统 ,阐述了系统的软、硬件设计 ,解决了DSP与PC间建立握手信号及进行数据通信的问题 ,并介绍了PC音频文件的格式与生成 相似文献
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本文主要介绍基于ASP.NET的人事管理系统的设计与开发过程。分析了该系统的需求,描述了系统的功能设计与实现,并对系统的功能与性能进行了测试。 相似文献
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The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation. 相似文献
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数字经济时代,企业面临更加激烈的市场竞争环境,传统的供应链管理模式的问题日趋显现,亟需进行数字化转型。企业的发展需要更加智能、高效的数字化供应链的支撑。针对这一现状和需求,文章着力于研究如何解决传统企业供应链数字化转型的问题,设计了一套基于SAP ERP和EWM系统为核心的企业数字化供应链的解决方案:通过SAP ERP和EWM系统的无缝对接实现了企业物流相关业务的自动流转;通过EWM与WCS系统的无缝对接以及WCS系统与自动化立体仓库硬件设备的集成实现了仓库所有出入库作业的自动传递和执行;通过引入条码技术以及与RF设备的集成实现了全流程作业的自动识别和准确高效的处理。该解决方案的设计与实现,帮助企业极大地提高了供应链各个环节的作业效率,提高了整个供应链的透明度,进而提升了企业的整体运营效率和管理水平,使得企业能在日趋激烈的市场竞争环境中保持竞争优势,并取得长足发展。 相似文献
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本文在概述红外热象技术应用于石化设备检测的基本原理和方法的同时,着重介绍了对石化重点装置催化再生器的检测及其衬时故障诊断,以及热管道、阀门外保温效果评估等方面的应用情况。并对此项技术在石化企业的应用前景和研究方向做了一定的介绍。 相似文献
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Three alternative schemes for secure Virtual Private Network (VPN) deployment over the Universal Mobile Telecommunication
System (UMTS) are proposed and analyzed. The proposed schemes enable a mobile node to voluntarily establish an IPsec-based
secure channel to a private network. The alternative schemes differ in the location where the IPsec functionality is placed
within the UMTS network architecture (mobile node, access network, and UMTS network border), depending on the employed security
model, and whether data in transit are ever in clear-text, or available to be tapped by outsiders. The provided levels of
privacy in the deployed VPN schemes, as well as the employed authentication models are examined. An analysis in terms of cost,
complexity, and performance overhead that each method imposes to the underlying network architecture, as well as to the mobile
devices is presented. The level of system reliability and scalability in granting security services is presented. The VPN
management, usability, and trusted relations, as well as their behavior when a mobile user moves are analyzed. The use of
special applications that require access to encapsulated data traffic is explored. Finally, an overall comparison of the proposed
schemes from the security and operation point of view summarizes their relative performance.
Christos Xenakis received his B.Sc. degree in computer science in 1993 and his M.Sc. degree in telecommunication and computer networks in
1996, both from the Department of Informatics and Telecommunications, University of Athens, Greece. In 2004 he received his
Ph.D. from the University of Athens (Department of Informatics and Telecommunications). From 1998–2000 was with the Greek
telecoms system development firm Teletel S.A., where was involved in the design and development of advanced telecommunications
subsystems for ISDN, ATM, GSM, and GPRS. Since 1996 he has been a member of the Communication Networks Laboratory of the University
of Athens. He has participated in numerous projects realized in the context of EU Programs (ACTS, ESPRIT, IST). His research
interests are in the field of mobile/wireless networks, security and distributed network management. He is the author of over
15 papers in the above areas.
Lazaros Merakos received the Diploma in electrical and mechanical engineering from the National Technical University of Athens, Greece, in
1978, and the M.S. and Ph.D. degrees in electrical engineering from the State University of New York, Buffalo, in 1981 and
1984, respectively. From 1983 to 1986, he was on the faculty of Electrical Engineering and Computer Science at the University
of Connecticut, Storrs. From 1986 to 1994 he was on the faculty of the Electrical and Computer Engineering Department at Northeastern
University, Boston, MA. During the period 1993–1994 he served as Director of the Communications and Digital Processing Research
Center at Northeastern University. During the summers of 1990 and 1991, he was a Visiting Scientist at the IBM T. J. Watson
Research Center, Yorktown Heights, NY. In 1994, he joined the faculty of the University of Athens, Athens, Greece, where he
is presently a Professor in the Department of Informatics and Telecommunications, and Director of the Communication Networks
Laboratory (UoA-CNL) and the Networks Operations and Management Center. His research interests are in the design and performance
analysis of broadband networks, and wireless/mobile communication systems and services. He has authored more than 150 papers
in the above areas. Since 1995, he is leading the research activities of UoA-CNL in the area of mobile communications, in
the framework of the Advanced Communication Technologies & Services (ACTS) and Information Society Technologies (IST) programmes
funded by the European Union (projects RAINBOW, Magic WAND, WINE, MOBIVAS, POLOS, ANWIRE). He is chairman of the board of
the Greek Universities Network, the Greek Schools Network, and member of the board of the Greek Research Network. In 1994,
he received the Guanella Award for the Best Paper presented at the International Zurich Seminar on Mobile Communications. 相似文献
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崔莹 《电子产品可靠性与环境试验》2009,27(4):10-14
基于美国宇航用电感器和变压器发生失效的类型、原因、检测方法和发生频次的数据,总结了其失效特征,并给出了电感器和变压器在MIL-STD-981中各项试验重要性的认识。通过对美国和国内宇航用电感器和变压器由设计、生产产生的失效和实验中失效的对比分析。给出了此类元件的失效特征。依据国情,提出了如何通过制定标准和失效数据分析工作来提高国产宇航用电感器和变压器可靠性的建议。 相似文献
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文中针对单相无刷直流电机结构设计及驱动方式展开研究,推导出电机理想工况下的基本方程,根据工程实际需求并结合无刷直流电机的设计原则确定该电机的设计方案。利用设计方案设计一台额定功率38 W,额定转速750 rpm的单相无刷直流电机,并分析了渐变气隙对电机起动性能和齿槽转矩的影响,确定了最优气隙长度。通过对比单极性绕组和双极性绕组形式的优缺点确定绕组形式,结合传统电机设计公式确定绕组匝数。文中利用有限元法初步验证了设计方案的合理性。根据电机动态数学模型在Simulink环境中搭建了电机系统的模型,仿真得到电机的转速、转矩变化曲线,结果与理论分析吻合良好,验证了电机设计方案的合理性和电机模型的有效性。 相似文献