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311.
基于传统意义上的飞控系统评估方法的不足,分析了风洞虚拟飞行试验应用于飞控系统评估的优势;按飞控系统常用的姿态控制回路及制导控制回路的组成形式,介绍了风洞虚拟飞行试验系统方案与工作原理,详细分析了它与半实物仿真系统的差异;分析了风洞虚拟飞行试验应用于飞控系统评估需解决的关键技术问题,包括风洞虚拟飞行试验评估方法、飞行器模型设计技术、飞控系统改进技术及模型支撑技术。  相似文献   
312.
采用激波管进行低浓度甲烷和空气混合气的着火实验,通过测量压力和OH发射光谱,得到不同工况下的着火延迟,并与甲烷的详细反应机理计算结果作比较。结果表明:不同浓度下甲烷着火延迟的对数与温度倒数呈线性关系,着火延迟随甲烷浓度的降低而减少;贫燃条件下,采用详细动力学机理计算的表观活化能与实验数据拟合较好。  相似文献   
313.
针对多波束干扰系统同时干扰多个目标的资源分配问题,通过分析目标分配算法的一般流程及涉及到的关键问题和技术难题,提出了基于实战化和有限条件的针对多波束干扰系统的非线性0-1整数规划数学模型。针对该模型采取开源软件SCIP进行求解,最后给出数值仿真来说明模型和算法的有效性。  相似文献   
314.

A statistically based enquiry into recruitment into the British Army over the period 1987-2000 shows that two factors tend to induce young men to enlist: high levels of unemployment in the civilian sector and positive signals from the authorities that the Army is in a recruiting phase. The same result obtains, broadly speaking, in the context of both white and non-white (ethnic minority) recruitment, although the willingness of ethnic minority young men to contemplate an Army career is only about a quarter of that of white men, other things being equal. Correspondingly, the Army shows no signs of reaching the target agreed with the Commission for Racial Equality in 1997 for a 1 percentage point increase annually in the percentage of recruits being drawn from the ethnic minorities. This article has something to say about how the Army might improve its performance in this regard by offering more in-service training and education to otherwise underqualified recruits and concentrating recruitment effort on regions of high ethnic minority unemployment.  相似文献   
315.
Book review     
La Conversion économique du secteur militaire, J. FONTANEL, Economica, Paris, 1994, pp. 112. Paperback. ISBN 2–7178–2650–5.  相似文献   
316.
Since the end of the Cold War, India's strategic horizons have moved beyond its traditional preoccupations in South Asia. India is developing a strategic role in East Asia in particular. At the same time India's strategic thinking has undergone a revolution, as the country that prided itself on non-alignment has moved closer to the West. But India's culture, history and geography still fundamentally shape its worldview. In engaging with East Asia, India is guided by a mosaic of strategic objectives about extending its sphere of influence, developing a multipolar regional system and balancing against China. The interplay of these objectives will frame India's role in East Asia in coming years.  相似文献   
317.
This article challenges the conventional wisdom that Neville Chamberlain rejected the British tradition of balance of power in the 1930s. In contrast to balance of power and balance of threat theories, states do not balance against aggregate or net shifts in power. Instead, leaders define threats based on particular elements of a foreign state's power. The import is that different components of power of a foreign state are more or less threatening and aggregate shifts in power alone may not provoke counterbalancing behavior. In the 1930s, Britain balanced against the most threatening components of power: the German Luftwaffe and the threat of a knock-out air assault against the homeland, Japan's Imperial Navy and its threat to Britain's commercial trade routes and the Dominions in East Asia, and the Italian Navy and the threat to Britain's line of communication through the Mediterranean Sea to India and Asia. Given Britain's difficult financial circumstances, all other components of power, such as the army and the land components of power of Germany, Japan, and Italy were ranked as secondary in terms of its rearmament priorities. Thus, London was able to narrow the gap with Berlin in specific components of power of strategic importance such as aircraft production or to exceed Germany in other areas such as the Royal Navy and its battlefleet.  相似文献   
318.
Theorizing about Taliban operations in Afghanistan has its limits and it is possible that Kabul-centric strategies do not adequately address the unique circumstances of each region in the country. How exactly has the Taliban gone about attaining its objectives in Kandahar province and how have those approaches evolved since 2002? And how have the Taliban adapted to coalition forces' attempts to compete with the insurgency and stamp it out? The answers to these questions are critical in the formulation of any counterinsurgency approach to Afghanistan.  相似文献   
319.
320.
航天测控系统任务可靠性分析的EOOPN模型   总被引:1,自引:1,他引:0       下载免费PDF全文
提出了一种可用于航天测控系统任务可靠性分析的扩展面向对象Petri网(extend object-oriented Petri nets, EOOPN)模型,旨在对给定的航天测控方案进行可靠性评估分析。针对问题特点明确了OOPN扩展思路,给出了EOOPN模型的形式化定义、运行规则和建模步骤,模型通过引入公共库所、激发弧、消息变迁和消息处理函数等概念,体现了面向对象的思想,具有很好的层次性和模块性。所建立的EOOPN模型能够完整的描述航天测控系统的组成和任务特点。通过对算例模型仿真运行,表明实验结果具有良好收敛性,与Markov解析值对比误差在1%以内,从而验证了模型的有效性。  相似文献   
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