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131.
构建满足完备性、精简性和查询快速性的导航星表是实现捷联惯性/星光组合导航系统的重要前提和保证。为了达到这一目标,本文选取天文学中的Tycho-2星表作为导航星表的初始星表,它与TRC星表相比具有明显的优势,在实践运用过程中更加完备。在Tycho-2星表基础上,对球矩形分区方法进行了改进,包括明确了分区及子分区的划分方法,提出了备选导航星的选择策略。实验结果表明,采用改进型球矩形分区方法的备选导航星数量最多只占赤纬带法导航星的19.39%,仅占全天遍历法导航星的3.12%。因此,改进型球矩形分区方法更加精准,查询更快捷,更适用于SINS/CNS组合导航系统。 相似文献
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133.
曾林彬 《兵团教育学院学报》2016,(4):58-61
职校的分层教学是根据职校教育的现状、针对不同层次中职学生的实际,在教学目标、内容、途径、方法上区别对待,使不同层次中职学生都能在其已有基础上很好发展的一种课堂教学策略。在职校数学课程改革理念的引领下,通过对学生自身状况的分析、做好中职学生的层次划分、不同备课目标的制定、不同课堂教学的设计、不同层次联系的布置、课后分层辅导的制定、评价等环节,更能展现因材施教的教学原则,对中职学生个性化教育有所帮助,同时,有利于培养中职学生的逻辑思维,改善当前数学课堂教学的情形,增强学生在数学中的应用能力,从而提高数学教学效果。 相似文献
134.
光纤位移传感器在喷油器针阀升程测量中的应用 总被引:1,自引:0,他引:1
传统的柴油机喷油器针阀升程测量方式多为接触式.文中提出运用光纤位移传感器进行喷油器针阀升程的测量,重点介绍了光纤位移传感器的原理、测量系统的组成、检测电路的特点等.实践表明,光纤位移传感器在喷油器针阀升程测量中的运用,实现了非接触测量,测量精度大大提高. 相似文献
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136.
依据炮瞄雷达故障诊断的需要,提出了一种智能化炮瞄雷达故障诊断专家系统设计方案。探讨了方案的组成,给出了实用诊断策略。 相似文献
137.
Richard Andres 《战略研究杂志》2013,36(3):395-422
In Operation ‘Iraqi Freedom’, as the Coalition's heavy forces fought in the South, in the North a handful of special operations forces, working with Kurdish rebels, clashed with the Iraqi army along the Green Line. In operations reminiscent of those used a year earlier to defeat the Taliban in Afghanistan, the lightly armed and heavily outnumbered Coalition forces called in air strikes to defeat Iraq's regular and Republican Guard army divisions. This article tells the story of these operations and discusses some of their implications for future US military policy. The success of the Afghan model in Iraq goes a long way toward demonstrating the efficacy of new air-heavy tactics and shows the strategic value of using light indigenous allies to replace heavy US land forces in both conventional combat and occupation operations. 相似文献
138.
Dr Paul Jackson 《Small Wars & Insurgencies》2013,24(2):145-160
Fourth Generation Warfare is a theory of contemporary warfare that posits a number of different ideas that are able to shed light on current conflicts. Whilst much of the debate has been concentrated on the linear development of warfare and also on analysis of the current situation of US forces in Iraq, it has resonance for a number of different conflicts taking place in Africa, if only because the US has become involved in contemporary conflicts in Somalia and the Mahgreb. There are clearly significant issues with the US-centric, flawed linear approach to history, but the actual analysis of modes of warfare has much to offer policymakers in a continent that is under-represented in the literature, and is also in danger of being forgotten in the shadow of analysis of Iraq. This paper moves on from criticising the stepped approach to history and looks at patterns of warfare in contemporary Africa, arguing that there is much in the theory that could be used to explain seemingly illogical tactics or patterns, and thus has much to tell policymakers engaged in conflict analysis. Rebellions can be made 2 per cent active in a striking force, and 98 per cent passively sympathetic.1 相似文献
139.
Andrew Mumford 《Small Wars & Insurgencies》2013,24(3-4):636-655
Making extensive use of primary archival documents, this article seeks to explore whether airpower in three of Britain's most significant post-war colonial counterinsurgency campaigns, Malaya, Kenya and South Arabia, was an unnecessary part of British strategy, offering little useful military force due to the futility and strategic damage rendered by offensive bombardment, or whether airpower was indeed an unsung factor that provided operational flexibility through its effectiveness in a supply context, as well as its intelligence role in providing valuable aerial reconnaissance. In all three case studies the role played by the RAF in medical evacuations, in troop drops, in crop spraying during food-denial initiatives, and in providing ‘Voice Aircraft’ for the propaganda campaign, provide insights into an under-explored component of Britain's politico-military efforts in counterinsurgency in the 1950s and 1960s and suggests that the main strategic value of airpower in counterinsurgency, then and now, lies in its non-kinetic functions. 相似文献
140.
A fundamental contradiction has been built into America's intervention in Afghanistan since the first days of the war in 2001. On the one hand, US policymakers have viewed the promotion of liberal democracy, economic development, and strong centralized state institutions as essential to achieve victory over the long term. On the other hand, however, the US has relied on local warlords to win its battles against the Taliban from the first days of the intervention. The Obama administration's tortured policy review reflects the intractable dilemmas involved in trying to build a modern democratic state while relying on local warlords as crucial allies in the war against the Taliban. 相似文献