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851.
介绍实时潜艇损管专家系统的设计与实现.该系统应用专家系统理论对潜艇损管训练及其在危险情况下进行损管决策领域的知识进行了建模,具有连续实时判断潜艇受损后的浮态和稳性以及制定损管决策方案和损管有效性检验功能. 相似文献
852.
Christopher Clary 《战略研究杂志》2019,42(5):677-700
ABSTRACTThis article examines decision-making mistakes made by U.S. President Nixon and national security advisor Kissinger during the 1971 India-Pakistan crisis and war. It shows that Nixon and Kissinger routinely demonstrated psychological biases that led them to overestimate the likelihood of West Pakistani victory against Bengali rebels as well as the importance of the crisis to broader U.S. policy. The evidence fails to support Nixon and Kissinger’s own framing of the 1971 crisis as a contest between cool-headed realpolitik and idealistic humanitarianism, and instead shows that Kissinger and Nixon’s policy decisions harmed their stated goals because of repeated decision-making errors. 相似文献
853.
低速磁浮列车利用电磁吸力支撑车体,相比轮轨列车具有噪音小、转弯半径小、爬坡能力强等优点。研究控制器输出饱和条件下悬浮系统的稳定性问题,可以避免由于电网电压约束而可能出现的失稳现象,提高了系统运行的可靠性。基于磁浮列车单点悬浮模型,使用电流-位置双环设计方法设计得到可稳定悬浮的控制算法。由于磁浮列车悬浮控制器的输出饱和环节,进一步提出了一种基于搜索极大椭球的控制参数优化方法,在不改变控制算法设计的前提下实现了参数优化。通过仿真和试验均验证了优化后的控制效果,有效指导了实际系统的工程调试。 相似文献
854.
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
855.
AbstractThe Sahel has gained attention in international politics as one of the central theatres in the war on terrorism. International actors in this war seek alliances with states in the region, reinforcing the latter’s military strength and their legitimacy from outside. At the same time, increasingly-connected young populations question the legitimacy of their states, and contest that legitimacy from within and below. In the absence of states delivering any reasonable form of social contract, young people become torn between different governing orders and find themselves in a liminal space. In this article we present the cases of youth in Mali and Chad, who find themselves in a period of re-definition of their position in society and hence search for legitimate structures representation. In this search they may frame their belonging in terms of ethnicity, religion or political opposition – and increasingly also in adherence to global citizenship. New information flows and connectivity among young people in these regions, and between them and the diaspora, has given a new turn to their search for citizenship/belonging and rightful representation. However, whether their search will be successful in this geopolitical context is questionable. 相似文献
856.
Olivier Chopin 《战略研究杂志》2017,40(4):532-553
ABSTRACTThis article argues that the intelligence sector is a privileged vantage point to observe and analyse a transformation of the State in France, as this transformation deeply affects the heart of the executive power and the French intelligence and security apparatus. Traditionally, intelligence was not conceived in France as a functional tool in the hands of the decision-maker but was rather defined as a ‘regalian power’. Intelligence activities were derived from a very specific conception of the State, and especially the particular notion of ‘reason of State’ (raison d’État). The current intelligence reform prompts speculation as to whether it represents more than a ‘simple’ functional reorganisation or in fact could signify that intelligence is now recognised as a tool in the hands of a ‘État de droit’ (‘liberal state’). The idea of a French ‘exceptionalism’ is addressed through a theoretical approach of the way France redefines intelligence and surveillance in relation with a major evolution of the notion of ‘reason of State’ itself. Then the article illustrates the assumption of a ‘lost tradition’ of reason of State through an analysis of the current reform of the intelligence sector in France. This reform is based on processes of rationalisation, centralization, modernisation and normalisation of both intelligence activities and intelligence services in France. As a conclusion, the article addresses the reactions to the January and November 2015 terrorist attacks in Paris, and asks whether resilience towards terrorism requires to accelerate the pace of the transformation of the French intelligence sector. 相似文献
857.
选取全球范围内72个基准站的坐标序列,采用改进的赤池信息量准则、贝叶斯信息量准则对不同噪声模型组合进行噪声分析,得到基准站坐标序列的最优噪声模型及速度参数,探讨时间序列跨度对噪声模型及速度估计的影响。结果表明,基准站坐标序列噪声模型不能由单一的噪声模型表述,其呈现出多样性特征,主要表现为幂律噪声、高斯马尔科夫噪声、闪烁噪声+白噪声特征,且三坐标分量表现出不同的噪声特性;随着时间跨度的增加,坐标时间序列的最优噪声模型、GPS站速度及其不确定度逐渐由发散趋于收敛,随机游走噪声模型的比重有所增加。结果表明10 a以上的时间跨度是较为理想的噪声模型估计尺度。 相似文献
858.
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
859.
860.
为解决防空反导体系对于目标意图识别中多源信息处理的问题,提出了一种新的防空目标识别方法——置信规则库(Belief Rules Base)识别模型,该方法是基于BRB专家知识系统的自学习方法,可以有效处理多源不确定性信息。同时,为了提高其识别效率,建立了一种与之相匹配的参数优化模型,并选择差分进化算法作为BRB识别模型的优化引擎。此外,在BRB识别模型中,专家意见也被引用到模型的初始化和推理过程中。最后采用一个实例对BRB识别模型的准确度进行验证。研究表明:该方法具有较强的实用性,可为防空反导体系的目标意图识别提供有力支撑。 相似文献