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981.
为实现对T/R组件剩余寿命的准确预测,及时掌握装备当前健康状态和提高装备维修保障水平,分析T/R组件的故障特点,筛选出反映T/R组件状态退化过程的状态监测指标,通过计算每个指标对应的剩余寿命信息和权重,得到T/R组件的剩余寿命预测结果。通过算例分析与比较,验证了预测方法的实用性与有效性。研究结果可为电子装备剩余寿命预测提供理论指导,对合理计划维修资源和提高装备战斗力具有重要意义。  相似文献   
982.
研究Gauss伪谱法在空空导弹最优中制导律设计中的应用。建立空空导弹中制导律设计问题最优控制模型,首次提出采用Gauss伪谱法求解最优中制导律设计问题的思路,详细阐述了求解流程,通过仿真算例验证了求解方法的有效性,并同比例导引、打靶法等传统方法进行了对比。仿真结果表明,综合考虑性能指标、计算精度、计算效率等因素,Gauss伪谱法具有明显优势,Gauss伪谱法求解结果和求解效率与配点个数密切相关。研究结果为空空导弹中制导律设计提供理论参考。  相似文献   
983.
为减小抗干扰接收机硬件实现难度,深入研究单天线卫星导航抗干扰相关接收机的性能,并详细分析其频域响应、信干噪比损耗和相关输出函数。分析表明,抗干扰最优接收机与相关接收机信干噪比损耗随着干扰带宽和干扰强度的增加而增大,随干扰频率与中心频率偏差和噪声带宽的增加而减小。此外,干扰将引起抗干扰接收机匹配与相关输出主峰降低和旁瓣抬高,从而影响接收机捕获、跟踪和多径抑制性能。研究结果将为卫星导航抗干扰接收机的优化设计提供依据。  相似文献   
984.
针对复合材料舵翼骨架与蒙皮连接,设计了两种T型连接结构,并对其在波浪砰击载荷作用下的极限承载特性进行了试验研究。根据结构承载特点,提取典型局部试验缩比模型,给出了均布压力下T型连接试验载荷等效方法。试验比较了两种T型连接的承载特性差异,研究了跨距对T型连接初始刚度、极限破坏载荷以及极限承载弯矩的影响规律。试验结果表明:构型A存在明显的初始破坏,但极限破坏载荷大于构型B;极限承载弯矩基本不随跨距改变,可作为不同跨距、不同构型T型连接优劣衡量标准。最后,基于试验结果、载荷等效与缩比原则,提出了T型连接承载特性评价方法。  相似文献   
985.
长码直扩信号的符号速率盲估计方法   总被引:2,自引:0,他引:2       下载免费PDF全文
针对长码直接序列扩频(DSSS)信号的符号速率估计的难题,提出了基于相关处理的方法。该方法首先估计长码直扩信号的相关函数二阶矩,然后将相关函数二阶矩的估计作为输入信号进行预处理,以去除扩频码周期处的峰值。对预处理后的信号再次进行自相关处理,则所得的信号的频谱中含有符号速率谱线。理论分析和计算机仿真证明了所提出的算法的有效性。  相似文献   
986.
ABSTRACT

This article analyses the positions of the Chinese civilian leaders and military elites on Military Operations Other Than War in order to shed light on their preferences about the use of the armed forces in foreign policy between the late 1990s and the early 2010s. Over time, a significant divergence developed between civilians and soldiers until 2011, when the Libyan crisis happened. The study also prompts important considerations about our understanding of civil–military relations in China and future role of the People’s Liberation Army as a tool of statecraft in foreign policy.  相似文献   
987.
ABSTRACT

This paper examines the importance of closer co-operation in defence-related procurement. Led by the decision that Belgium will lead the procurement of 12 Mine CounterMeasures Vessels (MCMV), the case of a potential Belgian naval construction cluster is discussed. The feasibility of a potential cluster is investigated by looking at key elements of a successful naval construction cluster, the Dutch naval construction cluster, and comparing those key elements to the current Belgian situation. Forming a sustainable Belgian naval construction cluster will be difficult. Most of the procurement process of the MCMVs is set on a European tender. In the long run, due to the absence of both a launching customer and leader firms, no party is able to carry the cluster with investments and knowledge spill-overs. In order to keep public support for large defence-related investments, clustering around the MCMV integration system and proactive cluster support is recommended.  相似文献   
988.
ABSTRACT

At the turn of the nineteenth century, China’s Qing dynasty (1644–1912) was hit by a sectarian rebellion. Commonly considered a breakpoint marking the end of the dynasty’s golden age spanning most of the eighteenth century, the war to suppress the rebels, referred to as the White Lotus War (1796–1804) in this article (‘White Lotus’ was the umbrella name used by both the authorities and some sectarians for their teaching), exposed many structural drawbacks of the Qing political and military systems and depleted the dynasty’s financial resources, which had never been recovered. Reluctant in embracing guerrilla warfare in the beginning, the insurgents quickly turned themselves into master guerrillas. Shuttling in two massive mountain ranges in central China, they managed to prolong their rebellion and fought some successful battles against their suppressors. Superior in manpower, weaponry, and logistical support, the government forces had to adapt to guerrilla warfare, albeit passively and ineptly. This article gives a brief introduction to this little-known episode of guerrilla war at the turn of the nineteenth century in Qing China, expounds the strengths and weaknesses of both sides, and sheds light on the roots of the war’s long duration and the grim consequences to the Qing state.  相似文献   
989.
ABSTRACT

The post-Cold War period nearly up to the present has been characterised as the age of liberal wars, yet key facets of the liberal guidance of war remain under appreciated. This article seeks to address this wider gap with regard to the particular concern of war termination and the fulfilment or failure of policy. First, it develops characterisations of liberal wars based on the existing literature, identifying three broad types through consideration of context—defensive versus offensive—and of political and strategic agency, particularly regarding the motives for and intents of action. Three types of liberal wars result: defensive liberal wars, offensive liberal wars with humanitarian motive and geopolitical intent, and offensive liberal wars with geopolitical motive and humanitarian intent. The article then presents one exemplary case for each liberal war with an emphasis on how liberal strategy required an illiberal ally and that ally's effect on the subsequent peace.  相似文献   
990.
We examine the validity of the guns-versus-butter hypothesis in the pre-Arab Spring era. Using panel data from 1995 to 2011 – the eve of the Arab uprisings – we find no evidence that increased security needs as measured by the number of domestic terrorist attacks are complemented by increased military spending or more importantly ‘crowd out’ government expenditure on key public goods such as health care. This suggests that both expenditure decisions were determined by other considerations at the government level.  相似文献   
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