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1.
主动防护网中钢丝绳网抗顶破力计算方法研究   总被引:3,自引:0,他引:3  
主动防护网以其轻便美观等优点而被越来越多地应用于边坡落石防护,现阶段针对某一具体的边坡防护工程,其防护体系的设计多根据设计者的经验确定。主动防护网主要分为起围护作用的防护网和起加固作用的防护网,针对起加固作用的防护网进行了研究。根据防护网的实际工作状况,提出了防护网抗顶破力计算模型,理论分析了单根网格绳对球体落石的作用及主动防护网中钢丝绳网对球体落石的作用,推导了单根网格绳及主动防护网中钢丝绳网抗顶破力的计算公式,为起加固作用的防护网设计提供一定的参考价值。  相似文献   

2.
This article is about the management of security incidents in organisations and companies which are under the protection of private security personnel, whether in-house or contracted. Incidents can be defined as accidental or anecdotal (bird flies into a camera) to a violation of law or company policy. Managing security incidents is one of the key functions of a private security service provider. The purpose of this study is to explore the management of security incidents and the information related thereto, identify shortcomings and find solutions for managing these shortcomings. Interviews were used to gain insight from personnel within the private and government sectors which are served by the private security industry. It was found that security incidents are handled in a routine way by organisations from the different sectors. One major shortcoming is that security incidents and the information related thereto are not managed by security service providers according to an operational framework or model with the required infrastructure and resources. The significance of this study is for security incidents to be managed correctly, so that the information related thereto may be captured accurately, analysed and used proactively and reactively to improve physical protection systems, develop preventative strategies and provide actionable information products in order to reduce crime, increase detection rates and prevent losses.  相似文献   

3.
This article aims to encourage the fostering of more systems thinking, and its greater exploitation, within the domain of contemporary intelligence. With particular focus on “micro systems thinking” and with reference to key intelligence processes, such as intelligence analysis, the utility of many systems dynamics within the intelligence context seeks to be further revealed. Through their greater collective harnessing, including up to “System of Systems” (“SoS”) dynamics, and promoting all that they can offer, more sophisticated overarching operational-to-strategic/policy “ends,” notably that of “defence-in-depth,” can be viably further advanced in a sustainable manner into the future. Arguably, a much-needed transformative impact on contemporary intelligence can also be increasingly realised through comprehensively engaging in and with more systems and SoS thinking. Aiding civil protection tasks, crisis management, emergency planners, and civil contingency practitioners likewise gain.  相似文献   

4.
阐述电磁防护工作中仿生研究所需要涉及的学科类型和基本内容,对所做工作在整个仿生领域中进行大致的定位;提出生物一电子研究的对等模型、总体构成和实现基础,细化具体研究的方向、设想和防护模式,并从原型实现的工程角度介绍实施策略,使得复杂电磁干扰环境下控制系统板卡及芯片级防护的仿生构想在技术上成为可能。  相似文献   

5.
飞行器在飞行状态时,控制导线在电快速瞬变脉冲群(EFT)作用下,该设备控制指令将会出现控制状态错误翻转、持续无指令输出等故障,产生故障的机理是电磁脉冲(EMP)通过传导方式进入控制箱产生紊乱的回输信号所致,严重时会损坏控制器及起飞装置。在实验基础上,研究了飞行器控制导线对电磁脉冲的防护加固方法,研究结果表明,对控制导线采取屏蔽法能够使飞行器对电磁脉冲具有很好的防护效果。  相似文献   

6.
We consider the burglar problem in which a burglar can either retire or choose among different types of burglaries, with each type having its own success probability and reward distribution. Some general structural results are established and, in the case of exponentially distributed reward distributions, a solution technique is presented. The burglar problem's relationship to a stochastic knapsack problem with a random exponentially distributed knapsack capacity is shown. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 359–364, 2014  相似文献   

7.
This article explores the potential impact of U.S. disarmament leadership on the nuclear diplomacy of North Korea and Iran, the “defiant states.” The first part of the article introduces the concept of “interaction capacity,” which measures a state's integration into international society, based on its physical communication systems and its adoption of shared norms. The theory predicts that lower levels of interaction capacity will generate a greater propensity for nuclear defiance, as the affected states reject and try to resist integration pressures. In the second and third parts of the article, this conceptual framework is applied to the cases of North Korea and Iran. The analysis suggests that efforts to reassert U.S. disarmament leadership could increase the alienation of North Korea and Iran, leading to provocation and escalation of nuclear tensions. The final part of the paper explores the policy implications of this analysis for the potentially defunct six-party talks, for hopes of renewed negotiations with Iran, and for the 2010 Review Conference of the Treaty on the Non-Proliferation of Nuclear Weapons.  相似文献   

8.
基于运行安全分析的核动力仿真软件的研究与应用   总被引:3,自引:2,他引:1  
对基于运行安全分析的核动力仿真软件的基本功能及其数学物理模型进行研究.运用工具软件对设备冷却水系统的正常与异常运行工况进行了仿真计算及结果的分析.与RELAP5/MOD3计算结果的比较表明,该软件可广泛用于核动力一回路辅助系统及二回路系统的仿真分析.  相似文献   

9.
《防务技术》2020,16(5):988-1000
The dynamic response of a multi-cabin protective structure subjected to impact load directly affects the protective performance of materials; thus, studying the dynamic response and communication law of wave effect of the load plays an important role in the prediction of protective performance. In this study, the protection experiments of box-structure under air- and/or water-medium are conducted, the dynamic response of the structure subjected to low-impact load is analyzed, and the corresponding numerical simulations are analyzed using the theory of finite element method (FEM). Combined with experimental and FEM simulations, the shock strain distribution, acceleration attenuation, and signal energy in defensive materials are determined. Based on the results, the metal structure exhibits good absorption characteristics for shock vibration. Using the experimental data, we also show that the attenuation of shock wave in water medium should be significantly better than that in air medium, and the protective structure should be designed for a combination of water and air mediums. Meanwhile, the numerical simulation can provide a quantitative analysis process for dynamic analysis of defensive materials.  相似文献   

10.
This article analyzes a capacity/inventory planning problem with a one‐time uncertain demand. There is a long procurement leadtime, but as some partial demand information is revealed, the firm is allowed to cancel some of the original capacity reservation at a certain fee or sell off some inventory at a lower price. The problem can be viewed as a generalization of the classic newsvendor problem and can be found in many applications. One key observation of the analysis is that the dynamic programming formulation of the problem is closely related to a recursion that arises in the study of a far more complex system, a series inventory system with stochastic demand over an infinite horizon. Using this equivalence, we characterize the optimal policy and assess the value of the additional demand information. We also extend the analysis to a richer model of information. Here, demand is driven by an underlying Markov process, representing economic conditions, weather, market competition, and other environmental factors. Interestingly, under this more general model, the connection to the series inventory system is different. © 2012 Wiley Periodicals, Inc. Naval Research Logistics 2012  相似文献   

11.
Abstract

‘[Sovereignty] is possible only within the framework of multinational communities, of common institutions designed to provide common responses to common challenges. Security is no longer attainable in the traditional way. Neither the walled city nor the nation-state can provide protection against attack or threats of physical destruction… Increasingly the politics of nations revolve around the careful management of interdependence.’  相似文献   

12.
基于ADC的炮兵激光观测仪侦察效能分析   总被引:1,自引:0,他引:1  
运用了效能分析方法,针对复杂战场环境下炮兵侦察系统的效能进行分析,特别是炮兵激光观测仪,揭示其内在规律,为提高现有侦察装备的作战效能找到重要途径,也为指挥员的决策提供可靠的战略支持.在侦察系统效能分析理论的基础上,对典型的激光观测仪侦察装备进行了计算评估验证,其方法和成果可供其他武器系统效能评估时借鉴参考.  相似文献   

13.
Given the advances made in conventional weapon capabilities, precision should by now be the accepted and expected norm in cyberspace as well. In this article I argue that developing precision cyber weapon systems, to be used during a lawful conflict, can be an important part of a responsible national security strategy to reduce the amount of violence and physical destruction in conflicts. I first describe a precision cyber weapon system in a military context. I then present three compelling rationales for the development of precision cyber weapon systems based on ethical, operational, and financial considerations. To support the position, I address several arguments that have been levied against their development. Thereafter I present several recommendations for a way ahead.  相似文献   

14.
Why did the Palestinian Authority established in 1994 create 12 security forces when Eritrea, which achieved independence in 1994, made do with one conventional army? This article attempts to explain the variation in the structure of national security systems in Third World states as a function of two basic factors: the state's political and social heterogeneity and the state's relative importance to US foreign policy and security concerns. Authoritarian one-party and centralizing states tend to fragment their security forces more than states that cultivate social or political pluralism. Fragmentation is a classic exercise of divide and rule. But a tradeoff exists between fragmentation and assuring internal security on the one hand, and ensuring offensive capabilities to ward off external enemies, on the other. Hence the importance of a strong foreign ally – preferably the United States. According to this model, centralized homogenous states enjoying US protection will tend to fragment or bifurcate their security systems most.  相似文献   

15.
The article is devoted to problems of defining quantitative criteria for the physical protection system (PPS) effectiveness of nuclear facilities. The article briefly describes the scheme of the PPS development used in the nuclear industry in Russia, gives a review of existing approaches to defining the minimal acceptable value of the system's effectiveness, and reveals advantages and disadvantages of the approaches. The article describes in detail an approach based on facility categorization by potential losses and a technique of defining the minimal acceptable value of the PPS effectiveness developed on its base.  相似文献   

16.
雷电流模型是自然雷电流的数学表达。通过雷电流数学模型可以得到建筑物防雷研究所关心的参量,它是建筑物雷电防护的基础。雷电流频谱分析对确定适合的雷电防护措施,消除或减弱雷电对建筑物弱电系统的破坏作用具有重要意义。选取双指数函数模型和霍德勒函数模型进行对比仿真分析和频谱分析,研究结果表明:霍德勒函数模型与BERGER等人的观测测量结果是一致的;雷电流所含频率丰富,且集中在低频部分。  相似文献   

17.
我国消防标准化工作现状分析与展望   总被引:1,自引:0,他引:1  
从消防标准化组织、消防标准体系、消防标准化管理和标准化国际交流四个方面介绍了消防标准化工作的现状。指出在消防标准与规范的协调性、消防标准体系建设和采标工作等方面存在的不足,进而得出增强标准与规范的协调性,建立消防管理标准体系,完善标准修订和采标机制是我国消防标准化工作的重点。同时结合国外消防标准化发展趋势,提出在实现消防标准国际趋同的同时,加快我国标准向国际标准的转化是今后较长时期内我国消防标准化工作的发展方向。  相似文献   

18.
This article concerns the effect of stochastic time delays in the operation of components upon system reliability for isolated impulse systems, for which component delays have hitherto been treated as deterministic. These are systems, such as automatic protective devices, which remain idle for most of their lives but which are required to respond with the utmost speed to input signals arising at arbitrary isolated time instants. System failure can arise from components failing to operate, or from being too slow to operate so that the systems operation is too slow to meet requirements. During operation components are usually subjected to greater stresses than during idling, so that it is assumed that components are subjected to increased failure tendencies during the time it takes them to perform their functions. The effect of stochastic time delays on the evaluation of systems reliability is considered, and a hierarchy of complexity associated with the physical nature of the delays in series and redundant configurations is exposed. Some simple exponential illustrations are presented.  相似文献   

19.
在重要战略机遇期,消防工作保障和服务经济社会发展的作用更加凸显。在研判重要战略机遇期的消防安全形势任务的基础上,从解决制约消防工作的体制性、机制性和保障性问题入手,提出了加强和改革消防工作的对策措施。  相似文献   

20.
The article argues that there is a relative lack of territorial power sharing in sub-Saharan Africa, but that this should not surprise us given the socio-ethnic context of most African countries which lack both majoritarian ethnic groups and clear culturally based distinctions between contending groups. A comprehensive analysis of the various federal systems and of some decentralising countries reveals a sobering record of conflict management and discusses some explanatory variables. In this context, forms of power sharing that include provisions on territorial autonomy, amounting to full-fledged federalism or restricted to some degree of decentralisation, should be regarded with caution. Regional autonomy as a solution to civil war will not work in most cases.  相似文献   

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