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Washington's so-called Maritime Strategy, which sought to apply US naval might against Soviet vulnerabilities on its maritime flanks, came to full fruition during the 1980s. The strategy, which witnessed a major buildup of US naval forces and aggressive exercising in seas proximate to the USSR, also explicitly targeted Moscow”s strategic missile submarines with the aim of pressuring the Kremlin during crises or the early phases of global war. Relying on a variety of interviews and newly declassified documents, the authors assert that the Maritime Strategy represents one of the rare instances in history when intelligence helped lead a nation to completely revise its concept of military operations. 相似文献
263.
Stephanie Lieggi 《The Nonproliferation Review》2013,20(2):395-399
The exploits of the A.Q. Khan nuclear network have received significant attention in the last three years. Gordon Corera's recent book, Shopping for Bombs, is an important addition to the existing literature. In this book, the author explores how Khan became a nuclear supplier and why his network was able to flourish for so many years. In his analysis, Corera examines relevant domestic and international political circumstances that affected Khan's rise and ultimate fall. The author also gives a compelling account of the international investigation that shut down this network in 2004 and warns that Khan's network will not be the last to challenge international nonproliferation regimes. Despite a few gaps in the book's narrative and analysis, Shopping for Bombs is an important source of insight into the activities of Khan and his network. 相似文献
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《Arms and Armour》2013,10(1):4-16
AbstractA review is presented of dual-ignition musket locks, including a matchlock, to identify the key design variants and their subtleties, and to initiate a discussion on their utility. 相似文献
267.
《Arms and Armour》2013,10(2):101-153
AbstractThe Sword of Honour (RA IX.1841) presented in 1856 by the Province of Nova Scotia to its native son, General Sir William Fenwick Williams, Bart. for his deeds at Kars, Turkey, is described, illustrated, discussed and placed both in its historical and its design context. Other notable British swords of the Victorian Age (1837–1901), the Age of Empire, are also examined and the various and influential aspects of their designs, ornament and iconography discussed. 相似文献
268.
机器人力控制存在着动力学不稳定性问题,即系统响应速度和稳定性之间的矛盾。在操作空间一级引人加速度正反馈,既能使系统的响应频带变宽,又能提高系统阻尼。这种方法能有效地提高机器人对高刚度环境的适应性,使力控制的动力学不稳定性问题得到明显地缓和;另外本文研究了用加速度积分信号代替位置差分速度信号来消除差分噪声,提高力控制精度方法的应用前景。 相似文献
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对液体火箭发动机碳/碳复合材料喷管的烧蚀过程进行研究。理论模型包括固相和气相守恒方程。气相湍流反应边界层流动应用质量加权平均控制方程分析,喷管壁温分布由非稳态传热方程进行数值计算获得。分析了推进剂混合比、液膜冷却量、燃烧室压力、壁面材料的密度对烧蚀速率的影响。 相似文献
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以某泵压式液体火箭发动机为研究对象,用试车数据对发动机静特性数学模型进行了验证,在验证模型时既考虑了外部干扰因素的实际测量误差范围和内部干扰因素的实际变化范围,又考虑了发动机参数实测量的误差范围,并且使用了随机仿真的方法。验证结果表明,发动机静特性的非线性数学模型是足够准确的,所用的计算方法是合理的。 相似文献