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101.
基于Volterra 级数理论,针对一类非线性系统,首先给出了此类系统可镇定的充分条件,接着讨论了非线性系统鲁棒镇定性的问题,并给出了系统鲁棒可镇定的条件;最后,用实例仿真来验证其有效性  相似文献   
102.
Since 9/11, counterinsurgency is back in fashion; the ‘war on terror’ has even been branded a ‘global counterinsurgency’. However the context within which counterinsurgency originally arose is critical to understanding the prospects for its present success; the radically changed environment in which it is currently being conducted casts into considerable doubt the validity of the doctrine's application by many national militaries currently ‘rediscovering’ this school of military thought today. Above all, classical counterinsurgency was a profoundly imperial, state-centric phenomenon; consequently it only rarely faced the thorny issue of sovereignty and legitimacy which bedevils and may doom these same efforts today.  相似文献   
103.
The US Army develops doctrine as a set of fundamental principles that guide its actions in support of national objectives. Recently, those national objectives required stability operations, with increasing scope and frequency. This study examines whether existing US Army doctrine adequately fulfilled its role as a guide to tactics in addressing the challenges that Army forces faced in the first 15 months of the war in Iraq. Field Manual 3-24 Counterinsurgency has remedied many deficiencies, but several remain to be addressed to offer commanders better guidance in the face of the many complex challenges they face in stability operations.  相似文献   
104.
ABSTRACT

Russian political leaders and military strategists are growing increasingly concerned about “strategic conventional weapons”—a broad category that appears to include all non-nuclear, high-precision, standoff weapons—and about long-range, hypersonic weapons, in particular. These concerns are complex and multifaceted (and, in some cases, contradictory), but chief among them are the beliefs that strategic conventional weapons could prove decisive in a major conflict and that Russia is lagging behind in their development. US programs to develop and acquire such weapons—namely, the Conventional Prompt Global Strike program—are of great concern to Russian strategists, who argue both that the United States seeks such weapons for potential use against Russia—its nuclear forces, in particular—and because strategic conventional weapons are more “usable” than nuclear weapons. Asymmetric responses by Russia include increased reliance on tactical nuclear weapons, efforts to enhance the survivability of its nuclear forces, and investments in air and missile defenses. There is also strong—but not completely conclusive evidence—that Russia is responding symmetrically by attempting to develop a long-range, conventionally armed boost-glide weapon.  相似文献   
105.
ABSTRACT

The United States and China are testing boost-glide weapons, long-range strike systems capable of flying at Mach 5 or faster through the upper atmosphere. For the United States, these systems would provide a conventional prompt global strike capability, which, together with US ballistic missile defense programs, Chinese experts regard as a threat to China's ability to conduct nuclear retaliation. This perception is encouraging the Chinese military to modify its nuclear posture in ways that tend to create greater risks for both sides. If China's own boost-glide systems are meant to carry nuclear payloads only, their deployment would not fundamentally alter the current situation between the two states. However, if they were conventionally armed or dual-purpose, or if the United States could not determine the payloads they carried, the deployment of Chinese boost-glide systems could compound problems of strategic stability created by the introduction of ballistic missile defense, antisatellite, and antiship ballistic missile capabilities. If the technical hurdles can be overcome, it may be difficult for the two sides to refrain from these deployments in the absence of strong mutual trust or an established arms-control relationship. New confidence-building measures and expanded mutual transparency are warranted to avoid creating new dangers.  相似文献   
106.
This article seeks to elucidate the concept of nuclear learning. It explores both the “nuclear” and the “learning” aspects of the concept. On the nuclear side, it distinguishes between learning basic facts about nuclear arms and drawing inferences about the larger implications of those facts. On the learning side, it discusses three issues: whether to use the term in a normative or value-neutral manner; the difference between learning that leads to a change in means versus learning that leads to a re-evaluation of ends; and whether learning only takes place at the level of individuals or whether there can also be learning by collective entities. The article argues there is no universal best answer to these questions and that the particular concept of learning that should be employed depends on the goals of the analyst. If the goal is to reduce the chances of nuclear war, however, one type of learning that will be important to consider is whether there is shared, cross-national learning.  相似文献   
107.
ABSTRACT

This article explores how two influential American policy makers—Paul Nitze and McGeorge Bundy—wrestled with the idea of a norm against the use of nuclear weapons. Existing scholarship has overlooked how both Bundy and Nitze came to understand the idea of nuclear non-use, especially related to the credibility of threats to use nuclear weapons. Using documentary evidence from their personal papers, this article illuminates the thinking of Bundy and Nitze, finding that both engaged with the idea of a norm of non-use of nuclear weapons in their strategic writing and thought.  相似文献   
108.
研究了FBN、JF402 2种碳氟表面活性剂与发泡剂配伍后形成的水溶液在油面上的铺展及泡沫性能(发泡力和稳定性)。结果表明FBN、JF402的加入可提高体系的铺展能力。FBN的铺展性能好于JF402,但JF402泡沫性能好于FBN。  相似文献   
109.
公安部科研项目“反应性物质热稳定性的分级方法研究”在国内首次利用绝热加速量热法系统研究了反应性物质的热稳定性。该项目研究成果在物质与生产火灾危险性辨识、火灾原因调查与分析等方面具有现实指导意义。在《工业企业防火》课程教学过程中,部分项目研究成果纳入了“影响储存和生产火灾危险性的因素”、“危险化学品的危险特性”“仓库防火”以及“重大危险源辨识”等章节的教学内容,使学生对课程内容有了更为深入地理解。科研成果与教学内容的有机结合,既显著提高了学生的学习主动性和学习兴趣,又大大增强了学生的创新性意识。  相似文献   
110.
计算原子钟频率稳定度时,钟差观测异常会导致Allan方差出现较大的估计偏差。建立Allan方差的差分估计模型,根据钟差的差分序列统计特性分析了相关差分估计的噪声识别与白化等计算复杂度问题;针对上述难点提出一种基于Huber权函数的非相关差分抗差估计方法,建立一种非相关差分序列的构造方法,有效避免了复杂的噪声识别及白化计算;给出Allan方差的非相关差分抗差估计的推导,并对抗差过程引入的误差累积给出了一种抵消方法;给出完整的抗差估计方案,并利用实测数据进行了实验验证。实验结果表明本方法对相位单点跳变、相位阶跃跳变具有显著的抗差能力,抗差估计可使异常引入的相对偏差由近200%降至10%以内。  相似文献   
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