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排序方式: 共有138条查询结果,搜索用时 31 毫秒
41.
ABSTRACTThe 1993 Highly Enriched Uranium (HEU) Purchase Agreement between the United States and Russian Federation is often described as one of the world's most successful nuclear nonproliferation programs. In 2013, the two states achieved the agreement's major goals of downblending 500 metric tons of Russian weapon-origin HEU to low enriched uranium (LEU) and delivering all resultant LEU to the United States. At one time, the LEU delivered under the agreement generated nearly 10 percent of all electricity in the United States. The agreement achieved its nonproliferation goals through a unique government/industry partnership. Commercial executive agents contracted for the annual sale and delivery of downblended LEU, while the US and Russian governments exercised reciprocal transparency monitoring measures to demonstrate that all LEU delivered under the agreement was derived from Russian weapons-origin HEU, and that the same LEU was used for exclusively peaceful purposes in the United States. The commercial development, negotiations, and implementation of the agreement have been well documented. This article describes the scope of US transparency monitoring activities in Russian HEU processing facilities, as well as Russian monitoring in the United States. In addition, it discusses the results of twenty years of reciprocal transparency monitoring and data analysis, and outlines lessons learned that are potentially applicable to future transparency monitoring and verification regimes and similar cooperative efforts. 相似文献
42.
Frank V. Pabian 《The Nonproliferation Review》2013,20(1):27-52
ABSTRACTSouth Africa's nuclear disarmament is a unique historical case, notable in part for the dramatic shift from deception to cooperation. The unprecedented transparency it demonstrated in order to convince the international community of the veracity of their disarmament is heralded as an exemplar for verifiable denuclearization. Less known is how this case affords insights into how a nuclear weapon program can be clandestinely hidden by the ambiguity provided by an otherwise completely legitimate, peaceful, nuclear energy program. Using a variety of open sources, including newly declassified internal South African and US government reports, it can be shown that South Africa employed a variety of deceptive tactics before it disarmed, and even for nearly two years after becoming a signatory to the Treaty on the Non-Proliferation of Nuclear Weapons. This article reviews that information to derive instructive lessons on the lengths that a nuclear proliferant state might go to conceal its true capabilities and intentions, and to thwart international discovery of the existence and full extent of an existing—or, in this case, a former—nuclear weapon program. 相似文献
43.
A rule that constrains decision‐makers is enforced by an inspector who is supplied with a fixed level of inspection resources—inspection personnel, equipment, or time. How should the inspector distribute its inspection resources over several independent inspectees? What minimum level of resources is required to deter all violations? Optimal enforcement problems occur in many contexts; the motivating application for this study is the role of the International Atomic Energy Agency in support of the Treaty on the Non‐Proliferation of Nuclear Weapons. Using game‐theoretic models, the resource level adequate for deterrence is characterized in a two‐inspectee problem with inspections that are imperfect in the sense that violations can be missed. Detection functions, or probabilities of detecting a violation, are assumed to be increasing in inspection resources, permitting optimal allocations over inspectees to be described both in general and in special cases. When detection functions are convex, inspection effort should be concentrated on one inspectee chosen at random, but when they are concave it should be spread deterministicly over the inspectees. Our analysis provides guidance for the design of arms‐control verification operations, and implies that a priori constraints on the distribution of inspection effort can result in significant inefficiencies. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004. 相似文献
44.
无人飞行器静稳定性问题的研究 总被引:4,自引:0,他引:4
从飞行器静稳定性的定义出发,介绍了3种不同的静稳定性,即纵向静稳定性、横向静稳定性和航向静稳定性。分别讨论了3种静稳定性的判据,进一步分析了影响静稳定性的部件和因素,说明了采用放宽静稳定性对无人飞行器产生的影响。 相似文献
45.
四足机动平台的静步态规划研究 总被引:1,自引:0,他引:1
基于仿生学原理进行了四足机动平台的腿部结构设计,分析了负载因子、周期、步距等步态设计参数对静步态稳定性的影响,提出了平地直行条件下从起步到稳定行走的步态调整方式,并对静步态行走全过程的稳定裕度进行了求解。计算结果表明:所规划的行走步态能达到静步态运动稳定性要求。 相似文献
46.
为了验证薄壳结构跌落冲击问题动态数值仿真的方法途径,设计制作了带有配重的薄壳结构,测定了材料主要力学性能,利用非线性有限元软件对该结构进行单次和累积结果的多次跌落冲击数值仿真,并进行了验证试验。对该结构的跌落冲击过程、典型位置的加速度响应、塑性变形的仿真、验证试验结果进行了对比分析,结果表明:采用的数值仿真方法和途径能够较好地研究分析薄壳结构的跌落冲击及其他同类问题。 相似文献
47.
郭艳丽 《中国人民武装警察部队学院学报》2005,21(2):27-29
分析了石油化工生产中静电的危害,根据静电产生的原因、引起火灾爆炸的条件分析静电导致火灾或爆炸事故的原因,并提出消除静电和预防静电火灾的对策。 相似文献
48.
以部队某保障基地油库军用柴油扩容工程采用钢板贴壁工艺新建的1座15 000 m3地下水封油池为例,从技术经济学角度对钢板贴壁油罐作了静态投资分析。该钢板贴壁油罐静态总投资1 756.95万元,其中占总投资比例最高者为地下工程建设,达到53.76%,库容投资1 171.30元/m3。结果表明:钢板贴壁油罐较地下水封石洞油罐整体经济效益明显;投资定额可供编制预算参考。 相似文献
49.
基于混沌变换良好的随机性和初始条件极端敏感性,提出了一种精确定位篡改位置的脆弱混沌数字水印算法.该算法将混沌加权后DCT中低频系数作为图像特征,利用混沌DCT匹配块对生成脆弱水印序列,最后嵌入到图像的DCT中频系数中.实验结果与分析表明,该算法几乎不影响图像的视觉质量,对图像篡改区域具有检测有效性和定位准确性,实现了盲认证.该算法不仅提高了篡改定位的精度,虚检率与漏检率也相应降低. 相似文献
50.
微型飞行器具有飞行雷诺数低、易受外界环境干扰等特点,并存在多目标优化问题,因此其气动布局优化设计难度较大。针对微型飞行器的特点及优化设计要求,采用N-S方程与遗传算法相结合的方法对微型飞行器的多目标优化设计,基于ISIGHT软件来实现该方法的具体流程,克服了计算量大、无法实现自主迭代的缺点。并对微型飞行器的展弦比、尾翼安装角、尾翼的高度和根弦长进行优化,优化目标为飞行器的静稳定性和升阻特性,优化后的构型具有良好的气动性能,结果表明该方法明显提高了计算的精度和优化设计的水平,在工程上有一定的应用价值。 相似文献