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71.
高等数学是大学教育中的主要基础课,与后续课程有密切联系。通过成绩统计和相关性分析,说明高等数学与其后续相关课程之间的关系和影响,提出数学教学的想法。 相似文献
72.
首先用矩量法精确分析了考虑互耦影响时天线阵元的电流分布,给出了计算电流的解析式,并仿真计算了单元直线阵的电流分布。然后以等效网络法为基础研究互耦影响存在时修正MUSIC算法的DOA估计性能,仿真实验表明在互耦影响存在时MUSIC算法失效,而修正MUSIC算法仍然具有良好的DOA估计性能。 相似文献
73.
破片模拟弹侵彻钢板的有限元分析 总被引:2,自引:0,他引:2
根据破片模拟弹侵彻钢板的实验研究,采用MSC.Dytran对破片模拟弹侵彻钢板的侵彻过程、侵彻特性、钢板的破坏模式以及弹体的侵彻速度、靶板的侵彻阻力进行了有限元分析,并将分析结果与实验结果进行了比较.分析结果表明,破片模拟弹冲击钢装甲的侵彻过程可大致分为初始接触、弹体侵入、剪切冲塞和穿甲破坏4个阶段.有限元分析的破片模拟弹侵彻特性及靶板破坏模式与实验观测结果有较好的一致性,在靶板破口的正面,与弹体平面凸缘两端接触的部分,变形以剪切为主,而与切削面接触的部分,以挤压变形为主;靶板破口背面为剪切冲塞破坏;有限元模拟的弹体剩余速度与实验结果吻合较好,弹体侵彻过程中弹靶作用界面的速度和侵彻速度近似呈线性变化.有限元分析结果还表明,采用适当的模型,有限元法能较好地模拟破片模拟弹侵彻钢板的侵彻过程、侵彻特性以及钢板的破坏模式. 相似文献
74.
George Michael 《The Nonproliferation Review》2013,20(1):143-147
Ron Rosenbaum, How the End Begins: The Road to a Nuclear World War III. Simon & Schuster, 2011. 305 pages, $28. 相似文献
75.
Oarhe Osumah 《African Security Review》2013,22(4):244-263
The armed conflict over crude petroleum oil in the Niger Delta has raged for several decades. A host of peace initiatives have been adopted by the Nigerian state to address it, but with minimal impact. The amnesty offer to repentant militias in 2009 by President Umaru Yar'Adua's administration is one of the most recent and broadest peace initiatives by the Nigerian government intended to end the general tendency to warfare and the absence of peace in the Niger Delta. This article, based on secondary sources of data, examines the components of the amnesty, its critical problems and their implications for peacebuilding in the Niger Delta. It finds that though the programme has engendered relative peace, the issues and grievances that occasioned the general tendency to warfare and absence of peace in the region – such as inequitable distribution of oil revenue, environmental degradation, and underdevelopment – are not properly articulated in the disarmament, demobilisation, and reintegration components of the programme. Thus, it holds that the prevailing situation in the region largely approximates a swinging pendulum of no war, no peace. 相似文献
76.
This article presents a proposed theory of how war economies are formed and maintained, as well as an integrated policy framework to guide the dismantling of war economies emanating from the proposed theory. Additionally, six potential areas for future research pertaining to the dismantling of war economies are also presented. 相似文献
77.
Roland Bensted 《African Security Review》2013,22(3):84-90
Paul Collier has produced a well-written and apparently plausible thesis on ‘greed and grievance’, evidenced in several published texts, which concludes unambiguously that greed, not grievance, is overwhelmingly the cause of conflict. However, Collier has based these findings upon narrowly defined quantitative measures–three defined indices of greed and four indices of grievance. Collier consciously omitted indices which he found difficult to measure, such as suppliers of armaments and opportunities for bureaucratic corruption. However, he appears to have unwittingly omitted some further factors, including governance, management mechanisms for natural resources and the influence that charismatic leadership can have on rebel groups. These omissions can be viewed as a major flaw in Collier's work. They also explain why Collier has diagnosed that civil wars are more likely to occur in some countries in the developing world without offering adequate explanation of why this may be so. 相似文献
78.
分析了战时装备调配保障决策的特点,运用模糊聚类分析法对装备调配保障对象进行了分组和优先级排序,以此为基础,运用目标规划法构建了战时装备调配保障决策模型,最后,通过实例验证了模型的可行性和有效性. 相似文献
79.
80.
Nothing fails like success: The London Ambassadors’ Conference and the coming of the First World War
Jared Morgan McKinney 《战略研究杂志》2013,36(7):947-1000
During the July Crisis Britain’s foreign secretary, Sir Edward Grey, focused on organising a conference through which differences could be reconciled. After the war, he maintained that Germany’s unwillingness to join this conference was one of the immediate causes of war. This essay disputes Grey’s contention, arguing that his plans for a conference, based on a misleading analogy to the previous Balkan Crises, actually helped facilitate the outbreak of war in 1914 by sanctioning inaction in the first phase of the crisis (28 June–22 July) and by tacitly encouraging Russian mobilisation in the second phase (23 July–4 August). 相似文献