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191.
基于动态球形空腔膨胀理论给出的阻力函数理论公式和开坑阶段的表面层裂机理,建立了能够综合考虑弹头形状、开坑区深度的斜侵彻深度预测模型,并进一步推导了能够适用不同弹头形状的弹体过载时程曲线计算公式。预测模型得到的侵彻深度和过载与试验结果吻合较好。研究结果可为弹体与混凝土靶的斜侵彻弹道分析和弹丸头部设计提供一定帮助。 相似文献
192.
针对航天器有限时间姿态机动问题,提出一种自适应二阶终端滑模控制算法。设计一种终端滑模面,保证系统状态能够在有限时间内沿滑模面收敛到系统原点;为克服系统抖振,设计了二阶终端滑模控制器,并采用参数自适应估计项补偿系统中的外部干扰力矩。基于Lyapunov函数法证明了二阶自适应终端滑模控制器能够保证闭环系统实际有限时间稳定。仿真结果表明,提出的姿态机动算法响应速度快、精度高,能够有效实现对系统抖振和外部干扰的抑制,具有重要的科学意义和工程应用价值。 相似文献
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Joshua Pollack 《The Nonproliferation Review》2013,20(2):411-429
North Korea has been one of the world's most active suppliers of ballistic missile systems since the mid-1980s, but the nature of its missile export business has changed significantly during this period. Unclassified, publicly available data show that the great majority of known deliveries of complete missile systems from North Korea occurred before 1994. The subsequent fall-off took place a decade too early to be explained by the Proliferation Security Initiative of 2003. It can be explained by a combination of factors that have reduced demand. First, after selling production equipment for ballistic missiles to many states, especially in the Middle East, North Korea by the late 1990s had become primarily a supplier of missile parts and materials, not complete systems. Second, after Operation Desert Storm, some missile-buying states shifted their attention away from ballistic missiles in favor of manned aircraft, cruise missiles, and missile defense systems supplied by Western powers. Third, some states experienced pressure from the United States to curtail their dealings with North Korea. During the last decade, having shed most of its previous customer base, North Korea has entered a phase of collaborative missile development with a smaller number of state partners, particularly Iran and Syria. Its known sales of complete missile systems are relatively small and infrequent. North Korea's time as missile supplier to the Middle East at large has ended, but there is a risk that regional states will turn to North Korea as a supplier of nuclear technology in the future. 相似文献
195.
Agnes Katona 《The Nonproliferation Review》2013,20(2):253-272
ABSTRACTSince 2002, NATO's territorial missile defense has evoked continuous debates between NATO states and the Russian Federation. Thirteen years have passed without reaching a common denominator. This article provides a comprehensive overview of the historical background of the debate and the technical details of the missile defense system, highlighting its shortcomings and the state of its deployment process. It also contrasts the military-technical and political arguments of both sides, before addressing the applicable norms of international law to highlight violations and the effect of this noncompliance on existing arms control measures. 相似文献
196.
针对目前水面舰艇对火力兼容性的需求,分析了基于垂直发射武器系统的火力兼容问题的特点。通过建立垂直发射导弹的弹道仿真模型及蒙特卡洛法仿真,分析了导弹垂直段和转弯段弹道的散布特点。结合弹道特点和火力兼容问题所研究的重点提出了建立基于垂直发射武器系统的火力兼容控制模型的方法,并初步给出了一个模型,对解决垂直发射武器火力兼容问题有一定借鉴意义。 相似文献
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Sumit Ganguly 《The Nonproliferation Review》2014,21(3-4):255-260
The question of nuclear stability in South Asia is a subject of both academic and policy significance. It is the only region in the world that has three, contiguous nuclear-armed states: India, the People's Republic of China, and Pakistan. It is also freighted with unresolved border disputes. To compound matters, all three states are now modernizing their nuclear forces and have expressed scant interest in any form of regional arms control. These issues and developments constitute the basis of this special section, which explores the problems and prospects of nuclear crisis stability in the region. 相似文献
199.
简要介绍了弹道导弹面临的典型防御系统。针对该防御系统,提出了弹道导弹所能采取的典型突防手段,并将弹道导弹突防措施分为反侦察类突防和反拦截类突防两部分,介绍了反侦察类突防中的电子干扰、诱饵、隐身、助推段策略以及反拦截类突防中的加强防御策略、导弹机动发射与飞行、多弹头策略等。为研究弹道导弹突防技术提供参考。 相似文献
200.