共查询到19条相似文献，搜索用时 125 毫秒
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计算机信息系统防雷工程是一个系统工程，它包括直击雷的防护、等电位连接措施、屏蔽措施、规范的综合布线、雷电电磁脉冲(LEMP)的防护、完善合理的接地系统6部分。 相似文献
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针对现代建筑雷电防护中等电位连接的概念、基本原则和几种特殊的等电位连接的问题进行了深入探讨,说明等电位连接技术的重要性. 相似文献
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随着信息系统的广泛应用，由于网络线多，电子设备的耐压水平低，雷击对信息系统的危害越来越大，防雷日益显得重要。雷电对信息系统的危害主要是雷击电磁脉冲（LEMP）造成的，包括沿线路传导的雷电过电压波、雷电流在接地线产生的高电位反击、雷击电磁场的静电感应和电磁感应。LEMP的防护措施有拦截、分流、等电位连接、屏蔽、接地、合理布线等。在信号线路上安装浪涌保护器（SPD）是信息系统防LEMP的一个重要措施，它可以同时起到拦截、分流、等电位连接的作用。 相似文献
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气象信息系统雷电综合防护技术的探讨 总被引：6，自引：0，他引：6
分析了雷电对广西气象台站的气象信息系统造成危害的主要原因，并提出了采用接闪、分流、屏蔽、合理布线、等电位连接、共用接地系统、过电压和过电流电涌防护等进行综合防护的主要措施。 相似文献
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自动站网络通信系统雷电防护包括广域网雷电防护、局域网雷电防护、光缆通信雷电防护等,这3种防护主要是防护雷电波入侵产生的感应雷以及由于自动站室内计算机局域网机房没有做好等电位连接造成的雷电损坏。1广域网雷电防护广域网的雷电防护主要是通信线、信号线不允许架空进入 相似文献
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本文提出了基于KKT条件的稀疏编码算法.首先,将非凸非光滑的稀疏编码问题分解成两个凸非光滑问题;然后,巧妙地运用两个矩阵使两个凸非光滑问题转换成三个光滑凸优化问题,并通过KKT条件对三个问题进行求解,再通过凸优化理论证明三个问题在其对应规则下是非增的.最后,实验结果验证了算法的收敛性. 相似文献
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近年来,多智能体系统的协调控制在多机器人合作控制、交通车辆控制、无人飞机编队和网络的资源分配等领域有着广泛的应用,成为当前控制学科的一个热点问题.首先介绍了多智能体系统的研究背景、智能体的概念和相关的图论知识;然后从多智能体系统协调控制包含的几个问题入手,即群集问题、编队控制问题、一致性问题和网络优化问题等,对其国内外的发展现状进行了总结和分析;最后,给出了多智能体系统有待解决的一些问题,以促进对多智能体系统协调控制理论与应用的进一步研究. 相似文献
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对于球坐标系下的水汽方程,当考虑水汽的凝结或凝华过程时,利用水汽方程的特点得到了关于水汽方程的弱极值原理的较强形式。利用该弱极大值原理,证明了对于第一类、第二类和第三类边值问题,水汽方程解的唯一性和稳定性。利用Schauder方法,证明了对于第一类、第二类和第三类边值问题,C2空间连续的水汽方程解的存在性。此外,还严格证明了水汽方程古典解的非负性。
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GRAPES_SDM沙尘模式应用及存在的问题 总被引：4，自引：0，他引：4
对中国气象局兰州干旱气象研究所业务化运行的沙尘模式———GRAPES_SDM的业务化过程、预报效果及其预报中发现的现象进行了总结。结果认为,该模式具有较准确的可预报性能,但是也存在一些需要进一步改善的问题。 相似文献
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A New Strategy for Solving a Class of Constrained Nonlinear Optimization Problems Related to Weather and Climate Predictability 总被引：2，自引：0，他引：2
There are three common types of predictability problems
in weather and climate, which each involve different constrained nonlinear
optimization problems: the lower bound of maximum predictable time, the
upper bound of maximum prediction error, and the lower bound of maximum
allowable initial error and parameter error. Highly efficient algorithms
have been developed to solve the second optimization problem. And this
optimization problem can be used in realistic models for weather and climate
to study the upper bound of the maximum prediction error. Although a
filtering strategy has been adopted to solve the other two problems, direct
solutions are very time-consuming even for a very simple model, which
therefore limits the applicability of these two predictability problems in
realistic models. In this paper, a new strategy is designed to solve these
problems, involving the use of the existing highly efficient algorithms for
the second predictability problem in particular. Furthermore, a series of
comparisons between the older filtering strategy and the new method are
performed. It is demonstrated that the new strategy not only outputs the
same results as the old one, but is also more computationally efficient.
This would suggest that it is possible to study the predictability problems
associated with these two nonlinear optimization problems in realistic
forecast models of weather or climate. 相似文献
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从市场的角度介绍国内外气象科技服务的现状,分析我国气象科技服务存在的问题和面临的形势,提出应对策略和建议。 相似文献
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Issues posed by global environmental change can be viewed as the problem of the commons on a larger geographic scale. A framework for analysing how geographic scale affects governments' ability to manage environmental problems is suggested here. It is based on interactions between four dimensions: production-consumption relationships; distribution of the benefits and costs of various activities; level of administrative control; and spatial scale of individuals' attachment to place. Global environmental problems can be viewed as a case where benefits from polluting activities are spatially concentrated relative to costs. The difficulty in addressing such problems stems from the discrepancy in geographic scale between adverse impacts and level of administrative control. The possibility of adapting institutional structures to match the scale of the problems is examined, in light of the increasing spatial scale of production-consumption relationships in the post-industrial world and the growing demand for local control across the globe. The geographic scale of ideological attachment to place is identified as an important variable in determining the ability to respond to large-scale environmental problems. 相似文献