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331.
基于响应面法的悬架系统优化研究 总被引:3,自引:0,他引:3
提出了应用响应面分析履带车辆悬架系统特性的方法。构建了悬架系统特性参数和整车行驶平顺性及可靠性之间的二阶响应面模型,并依据响应面分析结果,进行悬架系统的优化研究。优化结果表明了该方法的有效性。 相似文献
332.
Marc Widdowson 《Small Wars & Insurgencies》2013,24(3-4):478-506
The Christian resistance to the Arab invasion of Spain in 711 tends to be glossed over as a sideshow in what is usually presented as the inexorable progress of the conquest. This reflects the bias of our meagre sources, which mostly take the Arab perspective. Nevertheless, with close consideration and careful handling of these sources, we can draw from them an impression of a persistent insurgency that presented a real problem to the Islamic authorities and induced them to take both political and military countermeasures. This paper suggests how the resistance formed, its organization and tactics, and why the Arabs were unable to suppress it. 相似文献
333.
位置随动系统动态性能自动检测研究 总被引:1,自引:0,他引:1
通过分析某型位置随动系统的组成和动态技术指标,提出了位置随动系统动态性能自动检测的设计方案和测试方法,利用信号仿真模块和基于DSP的高速数据采集与处理模块,建立了自动检测的硬件电路和软件结构,确定了测试位置随动系统的动态性能指标、测试方法和软件功能,实现了对某型位置随动系统动态性能的自动检测. 相似文献
334.
针对水面舰艇反潜武器系统研制、火箭助飞鱼雷作战使用研究中对助飞鱼雷的仿真需求,重点研究了助飞鱼雷发射控制仿真方法和空中弹道仿真方法,突破了不同工况不同射程下发动机关机时间建模技术、保证大范围飞行一致性的火箭自适应控制器设计技术。应用表明,所形成的助飞鱼雷武器通道仿真模型能有效模拟助飞鱼雷从发射控制到弹道航行到命中目标的全过程以及作战效果,能够支撑助飞鱼雷发控算法研究以及作战使用研究。 相似文献
335.
Martin Schönteich 《African Security Review》2013,22(2):39-51
After only ten years in existence, the African Union (AU) has already made its mark on the landscape of peace and security in Africa. This paper seeks to explore the relationship between the AU's leading collaborative interstate security policy, the African Peace and Security Architecture (APSA), and sustainable peace in the Horn of Africa. It examines four countries – Djibouti, Eritrea, Ethiopia, and Kenya – and how engaging with the APSA through early warning systems can contribute to developing the elements necessary for sustainable peace, namely regional stability, conflict management, and good governance. 相似文献
336.
Since the July 2009 Boko Haram terrorist outburst in Nigeria, there have been increasing questions on the phenomenon in the country. There has not been any substantial analysis on the emergence of the Boko Haram group and its terrorist activities in Nigeria as the out-rage continues. This study is advanced to explain the phenomenon of Boko Haram terrorism in Nigeria. It employs the levels of analysis framework popular in the field of international relations to explain the terrorism at three major levels: individual, state and international. The study relies on dependable news reports, which include interviews with key actors relevant to the subject matter, and finds that Boko Haram terrorism has its roots in the ideology and motivations of its founder and members, the failures and deficiencies of the Nigerian state, and the modern trend of religious terrorism in the international system. 相似文献
337.
The criticism of James, Solberg and Wolfson (JSW) (1999) by Oneal and Russett (OR) is not responsive to the methodologica] issues at stake. JSW argued that war is an endogenous feature of the world political and economic system. If its causes are to be measured, it must be as a structural equation in a simultaneous system. Wedded to the idea that “democracies never fight each other,” OR rely on a single equation to justify their view. JSW claim that such an equation may be an ad hoc reduced form with no causal implications unless the equation is explicitly identified as a structural equation. JSW expand the model to explain democracy and conflict as two endogenous variables. JSW do not claim to have discovered the true relationships between these variables by their minimal expansion of the structural relation. They do show that unless these (and other) variables are treated as part of a system, the results are unstable, contradictory, of minimal size and not a reliable guide to public policy. 相似文献
338.
This article proposes two dual‐ascent algorithms and uses each in combination with a primal drop heuristic embedded within a branch and bound framework to solve the uncapacitated production assembly distribution system (i.e., supply chain) design problem, which is formulated as a mixed integer program. Computational results indicate that one approach, which combines primal drop and dual‐ascent heuristics, can solve instances within reasonable time and prescribes solutions with gaps between the primal and dual solution values that are less than 0.15%, an efficacy suiting it for actual large‐scale applications. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
339.
Serkan Eryilmaz 《海军后勤学研究》2013,60(4):313-320
Measuring the relative importance of components in a mechanical system is useful for various purposes. In this article, we study Birnbaum and Barlow‐Proschan importance measures for two frequently studied system designs: linear consecutive k ‐out‐of‐ n and m ‐consecutive‐ k ‐out‐of‐ n systems. We obtain explicit expressions for the component importance measures for systems consisting of exchangeable components. We illustrate the results for a system whose components have a Lomax type lifetime distribution. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
340.
Sten Rynning 《战略研究杂志》2013,36(1):53-72
This article explains why the EU in recent years has gained an upper hand in Allied defence planning. The development is surprising in light of reforms undertaken by NATO in the mid-1990s and also the 1998-99 US ambition to reinforce NATO's defence planning process with the Defence Capabilities Initiative. The article argues that a number of European governments, notably including the British and French, has been motivated to seek change because NATO's defence planning process has proved difficult to adapt to new low-intensity threats and also because governments seek to control the political development of the EU itself. The article illustrates how these concerns are directly visible in the current EU design for military planning and offers an assessment of future NATO-EU relations. 相似文献