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41.
Based on unique empirical data, including interviews with smugglers of radiological materials and the investigators who track them, this article discusses nuclear smuggling trends in the former Soviet republic of Georgia. Smuggling in Georgia mainly involves opportunist smugglers and amateurs, as opposed to professional criminals and terrorists; however, this does not mean that radiological smuggling is devoid of professionalism or organization. The article demonstrates that professional criminals are rarely involved in smuggling due to the unreliable nature of the market for radiological materials and the threat radiological smuggling could pose to professional criminals' ability to wield political power and operate legal commercial enterprises.  相似文献   
42.
ABSTRACT

Nuclear disarmament is often seen as eventually requiring access to nuclear warheads or to the warhead-dismantlement process to verify that a state has not hidden weapons or weapon-materials despite promising to disarm. This article suggests this view is misplaced, and that what is needed is a verification mechanism able to provide reliable assurances of the absence of fissile materials available for use in weapons after a state has disarmed. Such a mechanism will need an initial declaration of the amount of fissile materials held by a state for all purposes, military and civilian. In a state with a nuclear arsenal awaiting elimination, this declaration would have to include materials that may not be available for verification because they are in nuclear weapons or are in other classified or proliferation-sensitive forms. This article describes a verification arrangement that does not require access to materials in weapons and in sensitive forms while still allowing checks on the overall accuracy of the declaration. Verification of the completeness and correctness of the declaration is deferred to the time when the weapons-relevant material enters the disposition process, at which point it no longer has any sensitive attributes. By removing the focus on monitoring warheads and dismantlement, this new approach could provide a more manageable path to nuclear disarmament.  相似文献   
43.
针对组网雷达系统在跟踪目标发生机动时采用自适应滤波来估计目标状态的特点,在点迹融合数据处理结构的组网雷达基础上提出了一种欺骗干扰优化策略.根据状态和量测方程描述了组网雷达跟踪目标的模型,同时建立了跟踪机动目标的自适应滤波模型.在此基础上,建立了欺骗干扰模型,并在目标机动检测约束下,推导了虚假目标欺骗干扰对于组网雷达融合...  相似文献   
44.
重点分析了比幅测向系统的原理,在此基础上提出对其进行"主动反侦察"干扰的方法,推导了受到干扰下比幅测向系统的测量结果公式,讨论了不同条件下的干扰效果,并通过仿真进行验证。  相似文献   
45.
The responses of AI/PTFE reactive materials (RMs) under shock compression were investigated by a single-stage gas gun.A 3D mesoscale-model was established based on micro-computed tomography(micro-CT) slice images and confirmed with experimental results.In the high-pressure stage,the com-posites reacted partially,whereas there were no deviations between the partially reacted Hugoniot and the inert simulation results.The simulation reveals that the Teflon matrix melting on the high shock pressure.Melts and decomposition of the PTFE accelerated the diffusion of the atoms.Thus,the reactions of the Al/PrFE composites are more like a combustion rather than a detonation.  相似文献   
46.
采用自制的复合荧光粉体和化学载体成分,研制出一种步兵轻武器新型夜瞄复合荧光材料.试验研究和实际使用结果表明,研制的新材料发光时间长、亮度高,具有良好的耐温、耐腐蚀性能,不受轻武器的日常使用和维护影响,可满足步兵轻武器夜间瞄准需求.  相似文献   
47.
雷达信号仿真是抗干扰算法研究和验证的有效措施。针对箔条干扰随机信号模型难以满足高精度仿真的需要,本文在分析和总结箔条干扰散射特性和运动特性的基础上,对箔条干扰回波模型进行了更深入和精细化的研究。在Matlab平台上通过编程优化克服了复杂计算的问题,并获得了较好的模拟效果。仿真实验表明,该模型可为精确研究箔条干扰提供数据支持。  相似文献   
48.
弹道导弹突防措施分析   总被引:1,自引:0,他引:1  
简要介绍了弹道导弹面临的典型防御系统。针对该防御系统,提出了弹道导弹所能采取的典型突防手段,并将弹道导弹突防措施分为反侦察类突防和反拦截类突防两部分,介绍了反侦察类突防中的电子干扰、诱饵、隐身、助推段策略以及反拦截类突防中的加强防御策略、导弹机动发射与飞行、多弹头策略等。为研究弹道导弹突防技术提供参考。  相似文献   
49.
《防务技术》2019,15(3):241-253
This is a very timely review of body armour materials and systems since new test standards are currently being written, or reviewed, and new, innovative products released. Of greatest importance, however, is the recent evolution, and maturity, of the Ultra High Molecular Weight Polyethylene fibres enabling a completely new style of system to evolve – a stackable system of Hard Armour Plates. The science of body armour materials is quickly reviewed with emphasis upon current understanding of relevant energy-absorbing mechanisms in fibres, fabrics, polymeric laminates and ceramics. The trend in on-going developments in ballistic fibres is then reviewed, analysed and future projections offered. Weaknesses in some of the ceramic grades are highlighted as is the value of using cladding materials to improve the robustness, and multi-strike performance, of Hard Armour Plates. Finally, with the drive for lighter, and therefore smaller, soft armour systems for military personnel the challenges for armour designers are reported, and the importance of the relative size of the Hard Armour Plate to the Soft Armour Insert is strongly emphasised.  相似文献   
50.
针对停产雷达装备维修器材持续保障过程中存在的筹措断供问题,提出基于改进风险矩阵法和层次分析法相结合的风险评估方法。首先建立保障风险评估指标体系,然后采用改进的风险矩阵进行风险评估,利用采用层次分析法解决存在递归层次时风险因素的评估问题,最后得出装备器材持续保障风险的综合量化值,为提出保障风险规避策略提供数据依据。利用某型雷达器材保障风险评估案例进行数据分析,验证了该方法的有效性。  相似文献   
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