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防空导弹行进间发射技术初探 总被引:3,自引:0,他引:3
行进间发射技术是防空导弹技术的重要发展趋势之一,它能为机械化部队提供不间断的伴随防空,大幅增强武器系统的快速反应能力,提高了系统的生存能力,在综述各国行进间发射防空导弹型号基础上,对该技术的使用意义、装备特点和关键技术进行了总结。 相似文献
624.
分析了舰船全寿命期和使用期的结构,在此基础上,借助于WSEIAC模型,分别对舰船空调系统在两种保障方式的全寿命使用期效能和费用的各个指标进行了建模,提出了指标计算的思路与计算方法.结合海军舰船特点,在对WSEIAC效能模型进行修改和完善的基础上,给出了计算示例,结果显示了海军舰船空调系统采用岸基保障方式的合理性和优越性. 相似文献
625.
基于FMECA的某型雷达系统故障分析 总被引:2,自引:0,他引:2
故障模式、影响及危害性分析 (简称FMECA)是提高系统可靠性的一种有效的工具。在雷达系统故障分析中运用FMECA方法 ,通过计算机辅助程序实现了故障分析的预测分析和定量分析。与传统的故障分析方法相比 ,该方法能够避免分析中的盲目性和主观性 ,可以获得更为准确的分析结果 相似文献
626.
《防务技术》2020,16(3):543-554
Underwater acoustic signal processing is one of the research hotspots in underwater acoustics. Noise reduction of underwater acoustic signals is the key to underwater acoustic signal processing. Owing to the complexity of marine environment and the particularity of underwater acoustic channel, noise reduction of underwater acoustic signals has always been a difficult challenge in the field of underwater acoustic signal processing. In order to solve the dilemma, we proposed a novel noise reduction technique for underwater acoustic signals based on complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN), minimum mean square variance criterion (MMSVC) and least mean square adaptive filter (LMSAF). This noise reduction technique, named CEEMDAN-MMSVC-LMSAF, has three main advantages: (i) as an improved algorithm of empirical mode decomposition (EMD) and ensemble EMD (EEMD), CEEMDAN can better suppress mode mixing, and can avoid selecting the number of decomposition in variational mode decomposition (VMD); (ii) MMSVC can identify noisy intrinsic mode function (IMF), and can avoid selecting thresholds of different permutation entropies; (iii) for noise reduction of noisy IMFs, LMSAF overcomes the selection of decomposition number and basis function for wavelet noise reduction. Firstly, CEEMDAN decomposes the original signal into IMFs, which can be divided into noisy IMFs and real IMFs. Then, MMSVC and LMSAF are used to detect identify noisy IMFs and remove noise components from noisy IMFs. Finally, both denoised noisy IMFs and real IMFs are reconstructed and the final denoised signal is obtained. Compared with other noise reduction techniques, the validity of CEEMDAN-MMSVC-LMSAF can be proved by the analysis of simulation signals and real underwater acoustic signals, which has the better noise reduction effect and has practical application value. CEEMDAN-MMSVC-LMSAF also provides a reliable basis for the detection, feature extraction, classification and recognition of underwater acoustic signals. 相似文献
627.
Emerging sharing modes, like the consumer-to-consumer (C2C) sharing of Uber and the business-to-consumer (B2C) sharing of GoFun, have considerably affected the retailing markets of traditional manufacturers, who are motivated to consider product sharing when making pricing and capacity decisions, particularly electric car manufacturers with limited capacity. In this paper, we examine the equilibrium pricing for a capacity-constrained manufacturer under various sharing modes and further analyze the impact of capacity constraint on the manufacturer's sharing mode selection as well as equilibrium outcomes. We find that manufacturers with low-cost products prefer B2C sharing while those with high-cost products prefer C2C sharing except when the sharing price is moderate. However, limited capacity motivates manufacturers to enter into the B2C sharing under a relatively low sharing price, and raise the total usage level by sharing high-cost products. We also show that the equilibrium capacity allocated to the sharing market with low-cost products first increases and then decreases. Finally, we find that sharing low-cost products with a high limited capacity leads to a lower retail price under B2C sharing, which creates a win-win situation for both the manufacturer and consumers. However, sharing high-cost products with a low limited capacity creates a win-lose situation for them. 相似文献
628.
李志刚 《情报指挥控制系统与仿真技术》2010,(1):23-25
针对军事信息系统需求分析需要,探讨了作战活动过程描述、作战节点连接描述、节点状态转换描述和作战活动时序描述的内容和方法。基于该理论和方法,可以准确描述信息化条件下军事人员对军事信息系统的应用需求,实现军事人员与技术人员的有效沟通,为军事信息系统军事需求分析与应用设计的基础。 相似文献
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本文以P56半自动高炮系统为对象,介绍一个高炮人机半实物实时仿真系统的实现。主要包括系统设计思想和基本原理、硬件组成、软件设计以及系统主要特点。该系统的实现,为高炮人机系统提供了一个良好的研究手段。 相似文献