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361.
In 2013, the staff of the U.S. Nuclear Regulatory Commission estimated the reduction of the off-site economic losses from a fire in a drained U.S. spent fuel pool if fuel that had cooled for more than five years were transferred to dry cask storage—an option it called “expedited transfer.” In this article, it is shown that the savings would be much higher than the NRC estimated. Savings increase to about $2 trillion if: losses beyond 50 miles are included; the land-contamination threshold for long-term population relocation is changed to that used for the Chernobyl and Fukushima accidents and recommended by the U.S. Environmental Protection Agency; and, based on the experience of Japan, decontamination of land areas to levels acceptable for population return is assumed to take at least four years. If expedited transfer were implemented, the off-site economic losses would be reduced by about 98%.  相似文献   
362.
On 22 September 1979 two optical sensors on U.S. satellite Vela 6911 detected a double-flash of light that appeared characteristic of an atmospheric nuclear explosion conducted over the southern Atlantic or Indian Ocean. It became known as the Vela Incident, Event 747, or Alert 747. An anomaly between the amplitude of the two signals during the second pulse led a U.S. government expert panel established to assess the event to conclude in mid-1980 that a more likely explanation was the impact of a small meteoroid on the satellite, the debris from which reflected sunlight into the sensors' field of view. No model was presented to support the contention, and a similar anomaly—known as background modulation—was a given for the second pulse of all confirmed explosions detected by Vela, though beginning later. Nonetheless, this event has remained the subject of intense debate. This article reviews the evidence and presents an updated analysis of the original Vela signal based on recently declassified literature and on modern knowledge of interplanetary dust and hyper velocity impact. Given the geometry of the satellite, and that the bulk of the surface comprised solar panels, much of the debris from any collision would be carried away from the sensors' field of view. Thus, a meteoroid collision appears much less likely than previously assumed. The double flash is instead consistent with a nuclear explosion, albeit detected by an aged satellite for which background modulation was abnormal and/or commenced earlier, also seen in post-event SYSTEM tests. A companion paper to be published in 2018 presents radionuclide and hydroacoustic evidence supporting the conclusion that the Vela Incident was a nuclear weapon test explosion.  相似文献   
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This article assesses Bernard Fall’s concept of Vietnamese Revolutionary Warfare in Indochina between 1953 and 1958. It also investigates differences in the conceptualization of Revolutionary Warfare between Fall and proponents of French military doctrine known as la guerre révolutionnaire. The last component of the article considers limits of Fall’s influence on counterinsurgency doctrine.  相似文献   
367.
基于非线性Kalman滤波的导航系统误差补偿技术   总被引:1,自引:0,他引:1       下载免费PDF全文
针对非线性非高斯导航系统信息处理问题,采用自组织算法、神经网络和遗传算法等改进传统非线性Kalman滤波算法,构建一种自适应的组合导航系统。应用具有冗余趋势项的自组织算法、Volterra神经网络和遗传算法,建立导航系统误差的非线性预测模型,进而计算得到其预测值;将该预测值与Kalman滤波算法求得的估计值进行比较得到差值,以此监测Kalman滤波算法的工作状态;采用自适应控制方法,在导航系统结构层面改进Kalman滤波算法,构建新型的导航系统误差补偿模型。开展基于导航系统KIND-34的半实物仿真研究,应用所提出的改进方法改善了导航系统误差的补偿效果,提高了组合导航系统的自适应能力和容错能力。  相似文献   
368.
Abstract

Contemporary development assistance often takes the form of subcontracted state-building. Foreign donors hire for-profit firms to provide services and to improve or create institutions in developing countries, particularly those experiencing internal conflict. This arrangement creates two counterproductive dynamics: first, it introduces agency problems between donors, recipient states, subcontractors, and citizens; and second, it undermines the long-run development of domestic bureaucratic capacity by creating disincentives for the host government to invest. These dynamics hinder, rather than foster, the legitimacy of state institutions. This paper summarizes trends in external support to state-building since the 1970s and illustrates subcontracted state-building with examples from Colombia.  相似文献   
369.
In this paper I argue that a remotely piloted aircraft (RPA) pilot’s act of killing remotely, when it is done in the defense of another person, can be viewed as an act of sacrifice. This argument concludes from two premises. First, the RPA pilot faces psychological risk to self by carrying out such an action; second, the RPA pilot is motivated to some significant degree by something other than self-interest. Moreover, I challenge both the view that RPA represent merely an incremental development in technology yielding an incremental expansion of the distance between the war-fighter and the target and the view that RPA is revolutionary in some fundamental sense. I instead argue that, based upon the natural geometric boundary imposed by the earth’s shape, RPA have maximized the physical distance between the war-fighter and the target and, over time, this fact will change, not only the psychological effects on the RPA pilot, but also the way we view killing and distance in general. When taken together, these two broad claims, that other-defense can justify killing in war and that there is a psychological cost paid by remote killers, yield a conception of remote killing as an act of sacrifice that will inform the broader conversation about ethics, risk, killing, and RPA.  相似文献   
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This article analyses the main challenges and future prospects of creating United Nations (UN) rapid reaction mechanisms, particularly in the light of past attempts and current discussions about a “UN Vanguard Force” in the wake of the High-Level Panel on Peace Operations report. The article reviews major initiatives (in particular lessons from the Standby High Readiness Brigade for UN Operations) and assesses the main achievements, failures, and challenges related to past UN-led rapid reaction mechanisms. In line with the overall aim of this special forum, the article highlights the future potentials and institutional, operational, financial, and political challenges that need to be overcome in order to design and create a pragmatic and effective rapid reaction tool at the disposal of the UN.  相似文献   
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