计算机网络雷电防护中信号SPD对传输速率的影响

分析了雷电侵害计算机网络设备的几种途径,对电源系统、信号系统的防雷措施作了简单介绍,重点分析了浪涌保护器(SPD)在计算机网络中的保护作用及其对网络的影响,以及对网络参数进行测试的方法.     

计算机网络系统防雷措施浅析

1雷电侵害网络设备的几种途径雷电侵害计算机网络有两种方式:直击雷侵害和感应雷侵害。直击雷击中建筑物,会产生强大的雷电流,如果电压分布不均会产生局部高电位,对周围电子设备形成高电位反击,击毁建筑物,损坏设备,甚至造成人员伤亡。感应雷一般由电磁感应产生,通过电力线路、     

计算机通讯网络的防雷保护

通过对计算朵通信网络系统遭受雷击损坏的民政部进行统计调查和现场勘测,以及对其相应电路模型的理论分析和参考有关模拟试验数据,分析了计算机通信网络系统遭受雷击损害的主要原历以及可能的侵入途径。重点阐述计算机通信网络系统的防雷保护方案,主要介绍计算机通信网络接口或通信设备的防雷装置及其安装要求以及通信网络线路和地线回路的布放方式,相应的屏蔽措施等。     

计算机网络与通信系统中浪涌保护器的选择

针对雷击可能造成的雷击电磁脉冲对计算机、通信设备等微电子设备的危害情况,对雷电的分类、通信系统和计算机网络的雷电入侵途径进行阐述和分析.介绍了雷电浪涌保护器(SPD)的类型、组成元器件及主要技术指标;重点介绍在通信和计算机网络系统中SPD的选用原则和选型计算,通过对SPD最大持续运行电压、最大放电电流的详细计算,提出参照连接器类型,按照工作电压、工作频率的要求选择正确合理SPD的方法.     

浅谈计算机防雷技术

本文介绍了计算机遭受雷击的原因、途径及防护方法,对计算机防雷具有一定的参考价值。     

对于雷击电磁脉冲的认识

随着电气及电子技术的发展，各种类型的电子计算机系统越来越多，计算机设备对于电磁干扰的“敏感性”增强，雷击电磁脉冲引起有关部门的高度重视，2000年版的《建筑物防雷设计规范》增添了第六章“防雷击电磁脉冲”。     

简述计算机网络系统的防雷技术要点

介绍雷电是如何对计算机网络系统造成损坏的 ,阐述了计算机网络系统遭受雷击的原因及防止雷击的解决方法。     

雷雨季节计算机系统的保护

1　提高计算机自身的抗扰能力计算机通信系统遭受雷击损坏调查发现 ,在同一建筑物内或相邻建筑物内的计算机局域通信网络遭受雷击损坏的情况最为严重 ,其中以计算机同轴网络适配卡的损坏数量最多 ,其次是一些具有特定功能的接口适配卡。因此 ,计算机制造厂商有必要提高易损部件的抗扰能力。2　合理综合布线雷害现场勘察发现 ,大多数遭雷击的计算机网络所在建筑物屋顶有铁塔或避雷针 ,针体与建筑物主钢筋连接 ,并利用主钢筋应下泄入地中。在雷击放电时 ,建筑物内部产生较大的瞬变空间电磁场 ,由于计算机多采用总线制同轴网络 ,网络各工作站与…     

Milos500型自动气象站雷电过电压防护

雷电过电压幅值高、陡度大,自动气象站的微电子设备脆弱,一旦遭遇雷击则损失重大。据此。分析了自动气象站的雷电过电压强度、入侵途径,并参照通信系统的防雷措施,探讨了用接地防反击、电磁干扰,多级重点保护电源,加装保护器和保护通信线路及传感器、采集器等方法来防护雷电灾害。以确保自动气象站正常有效地工作。     

某电厂国税局信息系统雷击事故调查分析

某电厂国税局信息系统办公大楼位于双鸭山市东部地区55km处。2003年7月16日,双鸭山大部分市、县、区出现雷雨天气,该电厂国税局部分信息系统遭受雷击侵害,对计算机和通讯设备造成了很大损失。通过与有关人员座谈,了解当时的雷电情况,进行调查,对雷击现场进行详细分析,找出了事故的原因,并提出整改建议。     

Going to the Extremes

Projections of changes in climate extremes are critical to assessing the potential impacts of climate change on human and natural systems. Modeling advances now provide the opportunity of utilizing global general circulation models (GCMs) for projections of extreme temperature and precipitation indicators. We analyze historical and future simulations of ten such indicators as derived from an ensemble of 9 GCMs contributing to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC-AR4), under a range of emissions scenarios. Our focus is on the consensus from the GCM ensemble, in terms of direction and significance of the changes, at the global average and geographical scale. The climate extremes described by the ten indices range from heat-wave frequency to frost-day occurrence, from dry-spell length to heavy rainfall amounts. Historical trends generally agree with previous observational studies, providing a basic sense of reliability for the GCM simulations. Individual model projections for the 21st century across the three scenarios examined are in agreement in showing greater temperature extremes consistent with a warmer climate. For any specific temperature index, minor differences appear in the spatial distribution of the changes across models and across scenarios, while substantial differences appear in the relative magnitude of the trends under different emissions rates. Depictions of a wetter world and greater precipitation intensity emerge unequivocally in the global averages of most of the precipitation indices. However, consensus and significance are less strong when regional patterns are considered. This analysis provides a first overview of projected changes in climate extremes from the IPCC-AR4 model ensemble, and has significant implications with regard to climate projections for impact assessments. An erratum to this article is available at . An erratum to this article can be found at     

气象网络维护的小技巧

１引言气象业务网络有一个特点，就是处理的对象大多数是实时资料。因而很多计算机是不需要保留历史资料的（例如：PCVSAT单收站、MICAPS平台等），并且保证业务运行的系统软件和应用软件是固定的。基于这一点，为网络中处理实时资料的计算机做一个永久备份。当这些计算机出现不容易排除的故障时，就可以利用这些备份在几分钟之内恢复正常运行。下面介绍利用GHOST和DiskGenius两个软件来完成这工作的方法。２分区在分区的时候，为GHOST克隆出的映像文件划分一个独立的分区。如果使用的是WINDOWS９８操作系统，这个分区大小为５…     

利用防火墙软件实现市、县局用户共享上网

介绍采用WinRoute Firewall软件实现市、县局用户共享上网的方法,使市县局用户既能共享网络资源,又能有效地保障网络安全.     

Options to overcome the barriers to pricing European agricultural emissions

Although agriculture could contribute substantially to European emission reductions, its mitigation potential lies untapped and dormant. Market-based instruments could be pivotal in incentivizing cost-effective abatement. However, sector specificities in transaction costs, leakage risks and distributional impacts impede its implementation. The significance of such barriers critically hinges on the dimensions of policy design. This article synthesizes the work on emissions pricing in agriculture together with the literature on the design of market-based instruments. To structure the discussion, an options space is suggested to map policy options, focusing on three key dimensions of policy design. More specifically, it examines the role of policy coverage, instruments and transfers to farmers in overcoming the barriers. First, the results show that a significant proportion of agricultural emissions and mitigation potential could be covered by a policy targeting large farms and few emission sources, thereby reducing transaction costs. Second, whether an instrument is voluntary or mandatory influences distributional outcomes and leakage. Voluntary instruments can mitigate distributional concerns and leakage risks but can lead to subsidy lock-in and carbon price distortion. Third, the impact on transfers resulting from the interaction of the Common Agricultural Policy (CAP) with emissions pricing will play a key role in shaping political feasibility and has so far been underappreciated.

POLICY RELEVANCE

Following the 2015 Paris Agreement, European climate policy is at a crossroads. Achieving cost-effectively the 2030 and 2050 European targets requires all sectors to reduce their emissions. Yet, the cornerstone of European climate policy, the European Union Emissions Trading System (EU ETS), covers only about half of European emissions. Major sectors have been so far largely exempted from carbon pricing, in particular transport and agriculture. While transport has been increasingly under the spotlight as a possible candidate for an EU ETS sectoral expansion, policy discussions on pricing agricultural emissions have been virtually absent. This article attempts to fill this gap by investigating options for market-based instruments to reduce agricultural emissions while taking barriers to implementation into account.     

利用防火墙软件实现市、县局用户共享上网

介绍采用W inRoute F irewall软件实现市、县局用户共享上网的方法,使市县局用户既能共享网络资源,又能有效地保障网络安全。     

Framing the way to relate climate extremes to climate change

The atmospheric and ocean environment has changed from human activities in ways that affect storms and extreme climate events. The main way climate change is perceived is through changes in extremes because those are outside the bounds of previous weather. The average anthropogenic climate change effect is not negligible, but nor is it large, although a small shift in the mean can lead to very large percentage changes in extremes. Anthropogenic global warming inherently has decadal time scales and can be readily masked by natural variability on short time scales. To the extent that interactions are linear, even places that feature below normal temperatures are still warmer than they otherwise would be. It is when natural variability and climate change develop in the same direction that records get broken. For instance, the rapid transition from El Ni?o prior to May 2010 to La Ni?a by July 2010 along with global warming contributed to the record high sea surface temperatures in the tropical Indian and Atlantic Oceans and in close proximity to places where record flooding subsequently occurred. A commentary is provided on recent climate extremes. The answer to the oft-asked question of whether an event is caused by climate change is that it is the wrong question. All weather events are affected by climate change because the environment in which they occur is warmer and moister than it used to be.     

Energy input to the Earth

We review the physical origin, spectral nature, energetics and known variability of all solar emanations: photons, particles and magnetic fields. Compared to a decade ago, our knowledge has greatly improved concerning variability in the total irradiance, as well as its EUV and UV components. It is noted that synoptic EUV-UV irradiance data from space will cease in 1990 owing to space-craft orbital failures and the present launch hiatus. The case for variability in the past few centuries and predictions for the near term are given.