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991.
非相参多点源诱偏技术是对抗反辐射导弹(ARM)的有效手段。以ARM目标分辨的二分组理论和双点源诱偏的仿真结果为依据,对等功率三点源诱偏的2种经典布局的ARM落点整体分布进行预测。通过对ARM落点和系统被击中概率曲线的分析及拟合处理,验证了预测的正确性及系统被击中概率与占地面积的相关性,为通信辐射源抗ARM的布设提供一定的参考。  相似文献   
992.
计算机科学与技术专业课程体系的建设与实践   总被引:1,自引:1,他引:0  
计算机科学与技术专业是一门随着社会、经济、科技的飞速发展而不断更新的学科,为了培养具有开拓、创新、适应社会发展的高素质工程应用型人才,我们必须不断加强计算机科学与技术专业的课程体系建设。本文结合我校计算机科学与技术专业教学和应用现状,通过建立良好的课程体系,使课程教学能更系统、更具目的性;同时将实践教学摆到了重要的位置,注重课程体系的组织与学生能力培养和素质提高的密切结合。  相似文献   
993.
中学作文教学是整个语文教学中十分重要的一环,传统的作文教学方法忽视学生的主体作用,而"写前-写中-写后"三阶段作文教学法突出了语文教师应有的"引导"作用,在作文教学中侧重对学生主体性的调动,让作文教学在语文教师"导"的作用下更好地成为教与学的互动平台,进一步提高学生的写作能力。  相似文献   
994.
研究主题是指某一研究领域内的主要研究内容,反映了该领域的科研工作者和管理者的研究热点和工作重点。研究采用计量分析法对1994-2013年刊载在《学前教育研究》中与幼儿园"游戏"研究主题密切相关的165篇文献进行分析,建构了"游戏"研究主题的分析框架。回顾20年来幼儿园"游戏"研究,学术界对幼儿园游戏的关注度不够,游戏理论研究与实践研究的深度和广度均不足,理论研究与实践研究"脱离"现象明显。研究认为在以后的研究中,应树立"大课程"观的游戏理念;深化理论研究,建构本土化游戏理论;加强实践研究,探索游戏活动促进游戏者发展的路径;注重"关系"研究和"机制"研究,为理论研究和实践研究关联搭建桥梁。  相似文献   
995.
A common criticism levelled at successive governments of the Republic of Ireland during the Northern Ireland ‘Troubles’ was their alleged inactivity in the face of a ferocious Provisional IRA campaign. Such criticisms were based in large part on the perception of the southern state as a supply base for militant republicanism. The Republic was undoubtedly a formidable logistics hinterland for such militants. However, criticisms of the reactions of authorities in the south are unfair. This article considers the explosives capabilities of the IRA during the first six years of their campaign. It does so with reference to their attempts to obtain commercial explosives as well as measures employed by them to obtain homemade explosives. The article also considers countermeasures employed by the southern government and reveals the extent to which they sought to shut down IRA capabilities in the south. It is argued that, ultimately, the IRA's campaign in this regard could only be contained and never unilaterally halted.  相似文献   
996.
In the late seventeenth century during the Dutch War (1672–1678) and the Nine Years War (1688–1697), French armies relied on small war for the accomplishment of essential tasks and as part of an overall strategy of exhausting their opponents in the Low Countries. The purposes of small war included the imposition of contributions on enemy populations, the destruction of the enemy base of operations, blockades of fortresses, and the general support of campaign armies. The expression ‘small war’ in the French language appeared with growing frequency in the 1690s. Small war can be viewed as both a cause and consequence of the characteristics of these wars. The limited policy goals of Louis XIV the king of France required a strategy that minimised risk and accomplished the goal of reducing if not eliminating the Spanish presence in the Low Countries that bordered the north of France. As French armies increased in size during this period, the demand for specialists at small increased in order to provide security and ensure supply. Small war in the late seventeenth century was thus not ideologically motivated insurgency, but in the minds of French commanders an essential component of strategy and the nature of war.  相似文献   
997.
The insurrection in the Vendée combined open warfare with the methods of petite guerre, ambushing French republican soldiers and cutting their supply lines to Paris. These tactics, when combined with the hatreds generated by a civil war, go far to explain to the cruelty of the conflict in the west and the depth of the hatreds it engendered. In republican eyes the use of guerrilla tactics was unjust and illegitimate, and they denounced their adversaries as common criminals and brigands, portraying them as backward, superstitious, even as subhuman, and in the process justified the savage repression they unleashed against them.  相似文献   
998.
Secret French plans to launch guerrilla-style raids on the British Isles devised in the spring of 1796 were referred to as ‘chouanneries’. The name and concept behind these small-war operations were modelled on the irregular tactics used by the Chouan rebels in the Vendée, which the French state army had brutally quashed, but some wished to transfer into their institutional practice. Part of France's ongoing military strategy in the war against Britain, which included fomenting insurrection in Ireland, these irregular operations were to be manned partially by pardoned deserters and released convicts and prisoners of war. Of these, only Tate's brief invasion of Wales in 1797 was realised, but the surviving plans provide insightful historical lessons into an Anglophobic mindset shared by a small network of practitioners and policy deciders on the effectiveness of such shock and awe tactics. Largely motivated by the desire to take revenge for Britain's support of counter-revolutionaries in the Vendée, these plans could more aptly be referred to as counter-‘chouanneries’.  相似文献   
999.
目标选择是军事计划的关键要素之一。基于马尔科夫决策方法,解决具有复杂目标间关联的多阶段目标选择问题。使用与或树描述目标体系各层状态间的影响关联,并以目标体系整体失效为求解目的,建立了基于离散时间MDP的多阶段打击目标选择模型。在LRTDP算法基础上提出一种启发式方法,通过判断从当前目标体系状态到达体系失效状态的演化过程中的可能资源消耗和失败概率,来提供对当前状态的评估值,该方法能有效排除问题搜索空间中不能到达体系失效目的的中间状态,压缩了由于目标间复杂关联而增长的巨大状态空间。用实验验证了该方法有效性,实验结果表明,该方法直观实用,对目标间具有复杂关联关系的目标打击决策有一定参考价值。  相似文献   
1000.
竖立状态的运载火箭一旦遭遇地震,极易造成箭体倾倒等灾难性后果。为了确保运载火箭在地震中的安全,针对某型运载火箭,采用时程分析法对其进行地震响应分析,得到了火箭的弯矩、位移响应峰值沿箭体纵向的分布规律。分析了火箭关键位置处弯矩响应的频域特性,设计了火箭的减震措施,并分析了火箭与发射台的连接刚度、隔震支座刚度对火箭地震响应的影响规律。结果表明:火箭弯矩响应的最大值发生在靠近火箭尾段的位置,位移响应的最大值发生在火箭头部位置;改变火箭与发射台连接刚度以及在发射台底部加装隔震支座的方式可以有效地减小火箭的地震响应。  相似文献   
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