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61.
在地空导弹命中精度检验问题中,提出了充分利用单发导弹的测试数据进行命中精度的检验。该思想是利用χ2检验法对导弹速度的瞬时误差(系统误差)的方差进行检验,并给出了在测出导弹7、9、11个轨迹点条件下的2类风险临界值表,为武器精度检验提供了一定依据。 相似文献
62.
Person-borne improvised explosive devices (PBIEDs) are often used in terrorist attacks in Western countries. This study aims to predict the trajectories of PBIED fragments and the subsequent safety risks for people exposed to this hazard. An explosive field test with a typical PBIED composed of a plastic explosive charge and steel nut enhancements was performed to record initial fragment behaviour, including positions, velocity, and trajectory angles. These data were used to predict the full trajectory of PBIED fragments using a probabilistic analysis. In the probabilistic analyses a probability of fatality or serious injury was computed. Based on the results presented, many practical conclusions can be drawn, for instance, regarding safe evacuation distances if a person were exposed to a suspected PBIED. 相似文献
63.
Cyber operations are relatively a new phenomenon of the last two decades.During that period,they have increased in number,complexity,and agility,while their design and development have been processes well kept under secrecy.As a consequence,limited data(sets)regarding these incidents are available.Although various academic and practitioner public communities addressed some of the key points and dilemmas that surround cyber operations(such as attack,target identification and selection,and collateral damage),still methodologies and models are needed in order to plan,execute,and assess them in a responsibly and legally compliant way.Based on these facts,it is the aim of this article to propose a model that i))estimates and classifies the effects of cyber operations,and ii)assesses proportionality in order to support targeting decisions in cyber operations.In order to do that,a multi-layered fuzzy model was designed and implemented by analysing real and virtual realistic cyber operations combined with interviews and focus groups with technical-military experts.The proposed model was evaluated on two cyber operations use cases in a focus group with four technical-military experts.Both the design and the results of the evaluation are revealed in this article. 相似文献
64.
基于改进TOPSIS法的维修保障系统效能评估研究 总被引:3,自引:0,他引:3
维修保障系统涉及因素众多,对其进行效能评估是一项非常复杂的问题.在分析TOPSIS及其改进方法的基础上,构建了维修保障系统效能评估指标体系,应用改进TOPSIS法对维修保障系统效能进行了综合评估,并将评估结果与AHP和突变评价法的结果进行比较,结论一致.为维修保障系统效能评估问题寻求出一种新的方法,其评估结果可为决策提供定量依据. 相似文献
65.
Previous research has shown that the duration of a civil war is in part a function of how it ends: in government victory, rebel victory, or negotiated settlement. We present a model of how protagonists in a civil war choose to stop fighting. Hypotheses derived from this theory relate the duration of a civil war to its outcome as well as characteristics of the civil war and the civil war nation. Findings from a competing risk model reveal that the effects of predictors on duration vary according to whether the conflict ended in government victory, rebel victory, or negotiated settlement. 相似文献
66.
Tlohang W. Letsie 《African Security Review》2013,22(3-4):291-307
ABSTRACTThe Kingdom of Lesotho spends around five per cent of its annual budget – some 700 million Maloti ($US52.6 million) in 2017 – on the Lesotho Defence Force (LDF). Lesotho’s geographical position means that the LDF has no meaningful role regarding its primary function of defending the country from external aggression and it hardly engages in its secondary functions. In addition, the LDF has a long history of interference with democratic processes and engaging in human rights abuse. The financial resources currently allocated to the LDF could do far more for security, widely defined, if they were allocated to a number of other government expenditure categories. 相似文献
67.
This paper develops an endogenous growth model to examine the linkage between military expenditures and economic growth. We adopt the modeling strategy where both the supply side and the demand side effects of national defense are taken into considerations. Our result finds that a rise in military spending tends to stimulate the sustained growth rate, confirming Benoit's famous empirical findings. 相似文献
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