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1.
ABSTRACT

Recent nuclear-weapons-related consultation in NATO within the framework of the Defence and Deterrence Posture Review sheds light on historical experiences with nuclear consultation in NATO. In the early years of the Nuclear Planning Group (NPG), which became the main forum for multilateral nuclear consultation in the alliance, developing a nuclear weapons first use doctrine was of particular importance. This process led to the adoption of the Provisional Political Guidelines (PPGs) on the threat to initiate the use of nuclear weapons. With a focus on West Germany as the primary addressee of the NPG, it will be postulated that nuclear consultation functioned and may still be seen as an essential tool to manage the credibility of US extended nuclear deterrence in the framework of NATO.  相似文献   
2.
带三维落角约束的寻的导弹制导与姿控系统设计   总被引:1,自引:0,他引:1       下载免费PDF全文
针对带三维落角约束的寻的导弹制导与姿态控制系统设计问题,提出一种基于终端滑模控制和扩张状态观测器的六自由度制导控制系统设计方法。建立包含模型不确定项的寻的导弹六自由度质心与绕质心模型,设计内外双层环路六自由度制导控制系统框架;基于弹-目三维相对运动模型和坐标系转移矩阵建立以攻角和侧滑角为输入的三维全耦合导引方程,利用终端滑模控制方法和扩展状态观测器得到期望的攻角和侧滑角并将其转化为对应的俯仰、偏航和滚转角指令;根据线性形式的寻的导弹绕质心动力学方程,设计与俯仰、偏航和滚转角相关的滑模面向量,并利用终端滑模控制方法和扩张状态观测器得到寻的导弹的副翼偏角、方向舵偏角和俯仰舵偏角指令。六自由度数值仿真结果验证了该方法的有效性和鲁棒性,并证明了该制导控制系统设计方法能以较少的控制设计参数完成预设的制导控制任务。  相似文献   
3.
为了解决多个自主式水下无人航行器(AUV)在作曲线轨迹的航行时常规协同导航算法精度较低的难题,提出了一种基于极坐标的多AUV协同导航与定位算法.首先,将本算法的模型、可观测性与常规的直角坐标系算法进行了分析与对比.接着,进行了基于实航数据的数值仿真.针对解决各种传感器受异常噪声干扰导致多AUV协同定位误差变大的问题,本...  相似文献   
4.
为提高X射线脉冲星导航定轨精度,依据脉冲星导航原理,建立了X射线脉冲星自主导航系统的状态方程和观测方程,提出用强跟踪扩展Kalman滤波(Strong Tracking Extended Kalman Filter,STEKF)替代扩展Kalman滤波,并对3颗脉冲星卫星运行的位置和速度估计进行了仿真实验。仿真结果表明:STEKF具有使滤波器能够自适应地校正估计偏差并迅速跟踪状态变化的能力,有效地提高了卫星运动状态的估计精度和数值稳定性。  相似文献   
5.
对于可逆的二维保面积De Vogelaere映射,本文给出了n次迭代的线性Jacobi矩阵元的图形表示及其数学证明。  相似文献   
6.
ABSTRACT

To an observer, Japan’s approach to nuclear weapons can appear confused and contradictory. The only country to have been attacked with nuclear weapons is variously described as a pacifist and non-nuclear nation and as a proliferation threat. These widely varied and conflicting conclusions are understandable given that conflicting messages are sent by senior figures. However Japan’s stance is in fact a coherent, if not uncomplicated, response both to its security needs and to domestic public opinion. However, the security provided by US extended nuclear deterrence underlines and enables this approach. The key policies and decisions were taken in both Washington and Tokyo between China’s first nuclear test (1964) and Japan’s ratification of the Nuclear Non-Proliferation Treaty (1976). How the United States came to offer this additional security guarantee to Japan and how Japan came to rely upon it underscore this complex stance and are crucial to understanding a longstanding and ongoing security arrangement and source of stability and security in northeast Asia.  相似文献   
7.
ABSTRACT

Extended deterrence has been a main pillar of the security alliance between the United States and South Korea (Republic of Korea [ROK]) since the end of the Korean War. The changing dynamics of US extended deterrence in Korea, however, affected Seoul’s strategic choices within its bilateral alliance relationship with Washington. Examining the evolution of US extended deterrence in the Korean Peninsula until the Nixon administration, this article explains why South Korea began its nuclear weapons programme in a historical context of the US–ROK alliance relationship. This article argues that President Park Chung-hee’s increasing uncertainty about the US security commitment to South Korea in the 1960s led to his decision to develop nuclear weapons in the early 1970s despite the fact that US tactical nuclear weapons were still stationed in South Korea.  相似文献   
8.
针对目前混合气体识别大多采用传感器稳态响应信号、基于线性混合假设或大量样本学习,而瞬态响应信号特征分析主要应用非正交分解的问题,提出一种基于响应等效性与瞬态信号正交分解的混合气体识别模型。分析金属氧化物半导体传感器对混合气体的响应特性,建立基于气体响应成分等效性假设的气体非线性混合模型,在此基础上,提出并应用一种新的正交基函数——扩展类Legendre正交基,对气体传感器瞬态响应信号进行分解;通过对正交分解系数与气体浓度的回归分析,验证二者之间的指数型关联关系,并以正交分解系数为特征参数,利用气体非线性等效混合模型对混合气体分解与辨识。实验结果表明,尽管这种混合气体识别模型仅用单一气体检测的先验知识,对混合气体的识别误差仍可达到15%以内。  相似文献   
9.
空间机器人系统的机械臂和基座之间存在着动力学耦合,为了保证笛卡尔路径规划的同时可以调整基座的姿态,文章以冗余自由度空间机器人为研究对象,首先建立了空间机器人系统的运动学方程;由于存在一定的冗余度,通过将基座姿态运动方程与广义雅可比矩阵组合得到扩展后的雅可比矩阵,实现了基座和机械臂运动的协调规划;最后讨论了基座姿态无扰路径规划,并与零空间法进行了对比。建立平面三自由度空间机器人系统,分别采用零空间法和扩展雅可比矩阵法进行了基座姿态无扰路径规划和基座姿态跟踪路径规划,仿真结果验证了方法的有效性。  相似文献   
10.
ABSTRACT

The extended deterrence relationships between the United States and its allies in Europe and East Asia have been critical to regional and global security and stability, as well as to nonproliferation efforts, since the late 1950s. These relationships developed in different regional contexts, and reflect differing cultural, political and military realities in the US allies and their relations with the United States. Although extended deterrence and assurance relations have very different histories, and have to some extent been controversial through the years, there has been a rethinking of these relations in recent years. Many Europeans face a diminished threat situation as well as economic and political pressures on the maintenance of extended deterrence, and are looking at the East Asian relationships, which do not involve forward deployed forces as more attractive than NATO’s risk-and-burden-sharing concepts involving the US nuclear forces deployed in Europe. On the other hand, the East Asian allies are looking favorably at NATO nuclear consultations, and in the case of South Korea, renewed US nuclear deployments (which were ended in 1991), to meet increased security concerns posed by a nuclear North Korea and more assertive China. This paper explores the history of current relationships and the changes that have led the allies to view those of others as more suitable for meeting their current needs.  相似文献   
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