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71.
Albert Mauroni 《The Nonproliferation Review》2019,26(1-2):127-141
The US government initiated a Defense Counterproliferation Initiative to address the concern that, in the post-Cold War years, the proliferation of nuclear, biological, and chemical weapons would be widespread and create a significant challenge to the US military’s combat operations. In particular, non-nuclear states might use chemical or biological warfare agents against US forces with the belief that nuclear weapons would not be used against them in retaliation. Following the events of September 11, 2001, defense strategy and policy shifted to a wider view of the threat of adversarial use of “weapons of mass destruction” (WMD) and the term “counterproliferation” was replaced by “combating” or “countering WMD.” Over time, the Defense Department increasingly moved away from counterproliferation principles with the detrimental effect of losing capabilities that US forces still need for contemporary adversaries. This shift has been aggravated by other US government agencies’ use of “counterproliferation” in lieu of what would have been termed “nonproliferation” activities in the 1990s. The loss of clarity within the US government on these terms has led to the inability to focus the “whole of government” on this significant national security challenge. To alleviate this challenge, the US government needs a top-down initiative to refocus policy on the distinctly different aspects of WMD with respect to military combat operations, combating terrorism, and homeland security. 相似文献
72.
Neil Narang 《The Nonproliferation Review》2013,20(3-4):457-468
ABSTRACTThe popular use of the term “weapons of mass destruction” (WMD) can be understood to imply a relationship between nuclear, chemical, and biological weapons proliferation insofar as it assumes that the separate weapons technologies can be usefully grouped into a single analytic category. This article explores whether WMD is actually a useful construct. It begins by reviewing the literature on nuclear, chemical, and biological weapons proliferation, including a recent study that sought to estimate the relationship between the pursuit and acquisition of these different weapons. It then explores some policy inferences that academics and policy makers may be tempted to draw from these studies, particularly regarding the Barack Obama administration's pursuit of deep nuclear reductions. It argues that many of these policy inferences are premature at best and misleading at worst. It concludes with a call for additional research into the causes and consequences of chemical and biological weapons proliferation, and a call for scholars to remain cautious in their desire to draw premature policy implications from their studies in order to be “policy relevant.” 相似文献
73.
本文针对壳体带有大质量刚体的特点,用有限元离散方法,导出了在不同周向波数下壳元节圆位移与刚体质心位移及转角之间的关系式,并将结果与实际运动进行对比分析,论证了结论的正确性。为带有大质量刚体的壳体结构的动力分析提供了理论依据。 相似文献
74.
本文分析影响被炸药驱动下抛板极限速度的重要因素,讨论了一些经验公式的适用范围;提出了根据二维抛板的数值计算得到的两个重要规律:①在炸药与抛板的质量比相同的情况下,抛板的极限速度之间具有一定的相似关系;②修正的古尼公式可用来计算二维抛板的极限速度。 相似文献
75.
郭艳丽 《中国人民武装警察部队学院学报》2001,17(6):34-36,40
结合重特大恶性火灾案例,分析近年来国内发生群死群伤重特大恶性火灾爆炸事故的特点及原因,在总结以往事故经验教训的基础上提出遏制群死群伤恶性火灾的对策,并提出几点看法. 相似文献
76.
介绍了基于Simulink的质点外道模型的设计与仿真方法。首先给出了地面直角坐标系下的弹丸质心运动方程组,然后介绍如何采用Simulink建立系统的仿真模型并进行仿真计算。仿真方法具有模型设计过程简单、修改容易和结果直观等特点,可以应用到刚体弹道、火箭弹道及控制弹道等模型的仿真。 相似文献
77.
为了研究双质量飞轮的减振特性及其在汽车上的使用情况,在分析弧形螺旋弹簧双质量飞轮工作原理的基础上,经过理论推导,得到了应用于双质量飞轮的弧形螺旋弹簧的刚度计算公式,根据此公式完成了2个弹簧和6个弹簧双质量飞轮的弹簧参数计算和结构设计;建立了车辆动力传动系统的多自由度扭振分析仿真模型,对2种形式双质量飞轮减振效果进行了仿真分析。分析结果对设计适用于已知工况的双质量飞轮具有实用意义。 相似文献
78.
采用浸-烘循环的方法模拟干湿循环交替环境进行新型化学键合胶凝材料抗硫酸盐加速侵蚀试验.侵蚀溶液为质量浓度为5％的硫酸钠溶液,一组试验采用全浸-烘循环,另一组试验采用半浸-烘循环.在经受30×N(N=1,2,3,4,5)次循环后,测定试件的强度耐蚀系数和质量损失率,以此评价化学键合胶凝材料抗硫酸盐侵蚀性能.试验结果表明:半浸-烘循环的侵蚀比全浸-烘循环的侵蚀严重;在经受150次侵蚀循环后,试件外观无严重破损,质量不减反增,强度也不降低,说明化学键合胶凝材料具有优良的抗硫酸盐侵蚀性能. 相似文献
79.
Jiayi Lin;Hrayer Aprahamian;George Golovko; 《海军后勤学研究》2024,71(1):87-108
We study the problem of designing optimal targeted mass screening of non-uniform populations. Mass screening is an essential tool that is widely utilized in a variety of settings, for example, preventing infertility through screening programs for sexually transmitted diseases, ensuring a safe blood supply for transfusion, and mitigating the transmission of infectious diseases. The objective of mass screening is to maximize the overall classification accuracy under limited budget. In this paper, we address this problem by proposing a proactive optimization-based framework that factors in population heterogeneity, limited budget, different testing schemes, the availability of multiple assays, and imperfect assays. By analyzing the resulting optimization problem, we take advantage of the structure of the problem as a multi-dimensional fractional knapsack problem and identify an efficient globally convergent threshold-style solution scheme that fully characterizes an optimal solution across the entire budget spectrum. Using real-world data, we conduct a geographic-based nationwide case study on targeted COVID-19 screening in the United States. Our results reveal that the identified screening strategies substantially outperform conventional practices by significantly lowering misclassifications while utilizing the same amount of budget. Moreover, our results provide valuable managerial insights with regard to the distribution of testing schemes, assays, and budget across different geographic regions. 相似文献
80.
Dan Kuwali 《African Security Review》2013,22(3):248-269
The Constitutive Act of the African Union (AU) provides for the right of the continental body to intervene in the face of war crimes, genocide and crimes against humanity. According to its formulation, Article 4(h) intervention entails military force, which is triggered when a target state fails to discharge its duty to protect its population from mass atrocities. Although Article 4(h) is an ambitious statutory commitment to intervene in a member state by the AU, the Libyan crisis in 2011 showed the ambivalence of the continental institution to act in a decisive and timely manner. The AU's failure to invoke Article 4(h) exposed the need for building the capacity and political will to intervene and to interpret Article 4(h). Therefore, the primary focus of this article is on how Article 4(h) should be interpreted. Flowing from the Pretoria Principles, which seek to provide clarity on the implementation of the AU's right of intervention, Article 4(h) should be viewed as a duty rather than a right to prevent or stop mass atrocities. The duty dimension of Article 4(h) derives from the international instruments that AU member states have ratified to prevent mass atrocities. Rather than being a paper tiger, Article 4(h) should be used in a proactive and timely manner as a military option available to the AU to persuade member states to prevent or halt atrocities. As a last resort, military force pursuant to Article 4(h) should aim at protecting the population at risk and pursuing the perpetrators in order to avoid contravening Article 2(4) of the Charter of the United Nations (UN). Although military intervention can save lives in the short term, it cannot necessarily address the underlying, structural causes of atrocities, such as ethnic rivalries, economic inequalities and scramble for natural resources, among others. Therefore, the prevention of mass atrocities should not be equated with, or be seen through the prism of, Article 4(h) intervention alone. The focus should instead be on the entire spectrum of preventive strategies at the disposal of the AU in the face of mass atrocities, including the African human rights system and the African Peer Review Mechanism. 相似文献