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601.
脉冲力的瞬间作用会引起攻角和侧滑角的急剧变化,对末修弹飞行稳定性产生较大的影响.以线性化运动微分方程组为数学解析手段,对末修弹脉冲作用稳定性进行深入分析研究.数值仿真表明,采用小扰动法分析弹丸脉冲控制弹丸飞行稳定性是可行的.  相似文献   
602.
针对履带车辆下长坡制动过程中不同制动力的分配关系,在液力减速器和整车下坡动力学分析的基础上,研究了基于液力辅助制动的履带车辆下长坡制动控制策略,建立了基于SIMULINK的履带车辆整车动态仿真模型,对液力减速器的持续制动性能和控制策略的有效性进行了仿真.结果表明,车辆下坡持续制动时,适时应用液力减速器,能够有效分流整车制动功率,明显降低机械制动器的工作负荷,满足整车安全恒速下坡的要求.  相似文献   
603.
As the United States and Russia contemplate the next stage of nuclear arms reductions beyond the 2010 New Strategic Arms Reduction Treaty, another issue enters the agenda—that of the impact of possible deep reductions on the shape of the global nuclear balance. As the gap between the US/Russian arsenals and the arsenals of “second-tier” nuclear weapon states narrows, the familiar shape of the global balance, which remains, to a large extent, bipolar, is likely to change. The article explores the Russian approach to the relationship between further US-Russian reductions and the prospect of “nuclear multipolarity,” and assesses the relative weight of this issue in Russian arms control policy as well as the views on the two specific regional balances—the one in Europe (including UK and French nuclear weapons) and in Asia (the possible dynamic of the Russian-Chinese nuclear balance).  相似文献   
604.
Chinese writings on the workings of nuclear stability, deterrence, and coercion are thin and politicized. Nevertheless, it is possible to glean, from direct and inferential evidence, rather pessimistic conclusions regarding Chinese views of nuclear stability at low numbers. While China has been living with low numbers in its own arsenal for decades, today it views missile defense and advanced conventional weapons as the primary threat to nuclear stability. More generally, China views nuclear stability as wedded to political amity. Because none of these would be directly addressed through further US and Russian arsenal reductions, China is unlikely to view such reductions as particularly stabilizing. While there is little in Chinese writing to suggest lower US and Russian numbers would encourage a “race to parity,” there are grounds to worry about China becoming more assertive as it gains confidence in Beijing's own increasingly secure second-strike forces.  相似文献   
605.
ABSTRACT

Relations between the United States and Russia are in a prolonged downward spiral. Under these circumstances, cooperation on nuclear issues—once a reliable area of engagement even in difficult political environments—has all but completely halted. There are urgent reasons to find a way out of this situation, particularly the expiration of the New Strategic Arms Reduction Treaty in 2021. However, seemingly intractable disagreements about noncompliance with the Intermediate-range Nuclear Forces Treaty and US ballistic-missile defense, compounded by the Ukraine crisis, the conflict in Syria, and the accusations of Russian interference in the US election of 2016, threaten the future of arms control. Against this backdrop, policy makers and practitioners should identify ways to re-engage on nuclear issues now so they can be ready to implement them as soon as feasible. This article considers how the Comprehensive Nuclear-Test-Ban Treaty (CTBT) could serve as a platform for US–Russia cooperation on nuclear issues when circumstances permit. Taking into account the challenges posed by ongoing US non-ratification, it identifies a menu of CTBT-related activities short of ratification that the two countries could undertake together. It explores how joint work on this issue would advance shared US and Russian interests while helping to create the circumstances necessary for further arms-control work.  相似文献   
606.
ABSTRACT

Whereas much of the debate about the demise of the 1987 Intermediate-range Nuclear Forces (INF) Treaty has focused on the European context and Russia’s alleged treaty violations, Asia looms large in the minds of proponents of the United States’s immediate withdrawal from the treaty. For many proponents, the fast-changing military balance in Asia and China's conventionally armed missiles constitute a sufficient cause for withdrawal. What does the end of the INF Treaty bode for the US-China military balance? This article argues that, although there are some near-term benefits for the US position in the conventional military balance with China, the advantages offered by prohibited missiles are minor and can be readily substituted by extant capabilities that are compliant with the treaty. Given the negative implications of the end of the INF Treaty for the future of arms control, the costs and benefits of withdrawing from the treaty require further examination; the military balance in Asia is an unpersuasive rationale for withdrawing from an important part of the arms-control architecture.  相似文献   
607.
总结论述了美国和英法国家的飞机电磁弹系统工程化应用研制的发展状况,综述了电磁弹射用直线电机的方案选型设计、仿真技术、性能优化和控制方法等方面的关键技术和研究现状,针对电磁弹射技术的发展前景和应用给出了相关建议,为国内电磁弹射相关技术的发展提供了借鉴。  相似文献   
608.
无人机测控系统Turbo-MAP译码方法   总被引:1,自引:0,他引:1  
无人机测控数据链系统与地面控制站进行的是遥测数据、侦察图像及遥控指令的传输,因此,高质量的通信是确保无人机数据链发挥效能的关键技术之一。针对无人机信道的特点和要求,研究了无人机信道的Turbo-MAP译码模型,提出一种无人机测控系统Turbo-MAP译码方法,并针对各种参数条件进行了Matlab仿真。实验结果证明,该方法能够保证在发送数据的时候尽量使用长度较长的数据包且增加交织深度,并显著提升译码BER性能。  相似文献   
609.
在战场环境中,探测出敌方网络拓扑结构,为寻找网络最佳攻击点奠定了基础,具有重要意义。在研究数据链组网原理的基础上,研究了多址接入方式的探测方法,并提出了基于辐射能量分析的网络拓扑结构探测新方法。该方法通过对信号进行时频分析并结合互联关系矩阵来进行网络拓扑结构判断,仿真结果表明该方法可以有效地判断出敌方的网络拓扑结构和多址接入方式。  相似文献   
610.
介绍了一种新型的变距桨控制系统。通过采用不同的控制方法,提高了螺距角的控制精度、稳定性和跟踪响应的快速性,使原系统的可靠性大大提高。  相似文献   
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