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361.
秦有权 《国防科技》2017,38(1):001-007
通过分析空袭兵器、空袭历史、防空体系和防护技术的发展,将空袭模式划分为防区内(低空)地毯式打击、防区内(中低空)多手段打击、防区外陆海空三位一体精确打击三代。将防护体系划分为"边陲墙壕烽火台+腹地城池"、"防空系统+防护工程"两代。并预测了第四代空袭模式:防区外陆海空天四位一体全球快速精确打击和与之相对应的第三代"防空反导+信息化防护工程"防护体系。根据打击力和防护力相生相克的矛盾运动,提出了末端防护工程应吸收信息技术、发展综合防护技术,信息化时代的防护工程不仅要保护可以转入地下的目标,而且要保护无法转入地下的目标。从源头上为陆基目标防护的研究和建设提供参考和启迪。  相似文献   
362.
军队建设和未来战争呼唤高素质复合型的军事人才.抓紧培养和造就一大批高素质复合型军事人才,是我军建设的战略选择和根本大计,也是我军院校的神圣职责和光荣使命.而要培养高素质复合型军事人才,必须首先更新教育思想观念,并以先进的教育思想观念为指导,确立科学的人才目标模型,优化教学总体设计;必须在加强课程教学上下功夫,把教学内容作为深化改革的核心和关键,同时抓好与其相适应的各项配套改革,确保整个教学改革协调一致的发展;必须不断创新军事人才培养模式,全面提高办学水平,从机制和实力2方面来保证培养目标的实现.  相似文献   
363.
基于概率推断网的水雷战专家系统   总被引:1,自引:0,他引:1  
针对反水雷作战决策的需要,运用贝叶斯推理、模糊逻辑以及可信度不确定推理方法,设计了一个基于概率推断网的水雷战专家系统.利用该系统可得出两种结论:一是利用计算概率的方法得出的结论,二是利用计算可信因子方法得出的结论,两种结论呈现定量和定性的互补关系.可较好地为反水雷作战指挥员提供辅助决策,以减少舰船遭毁伤的概率.  相似文献   
364.
为了尽快分析出未知水雷障碍参数,根据水雷战的特点,提出了建立未知水雷障碍参数分析专家系统的观点,对专家系统的设计方法进行了一定的探讨,并针对专家系统建立中的"瓶颈"问题,提出了基于Vague集插值近似推理的专家系统知识自动获取方法,在介绍推理过程的基础上给出了算例.从推理的结果来看,该方法具有较高的可信度,从而为专家系统的研制提供了一定的方法支持.  相似文献   
365.
《防务技术》2020,16(4):883-892
The influence of initiation modes on the explosive dispersion process of the multi-layer composite charge (MCC) was studied. Overpressure sensors and high-speed photography system were used to investigate the energy release process of an MCC with a specific structure. The shock wave pressure and explosive dispersion characteristics of the MCC under different initiation modes were compared. The forming and expanding process of the shock wave of the composite charge under different initiation modes was determined. The separation position of the shock wave and fireball interface was determined. The calculation formulas of the shock radius and overpressure of the composite charge are presented. The radius of the shock wave of the composite charge was significantly affected by the initiation mode. Moreover, the development process of the composite explosive fireball under different initiation modes was analyzed, the variation rules of the composite charge dispersion radius and fireball dispersion velocity with time were obtained under the different initiation modes, the explosion energy release rate of composite charge under simultaneous initiation modes was the highest, and the peak overpressure under the simultaneous initiation mode was 1.61 times that of central single-point initiation.  相似文献   
366.
《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   
367.
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   
368.
采取等效电路模型仿真和加速退化试验相结合的方法研究温度对半导体激光器不同退化模式的影响规律。针对半导体激光器有源区退化和腔面退化进行分析,发现有源区退化会使半导体激光器阈值电流增大,而腔面退化会使半导体激光器斜率效率减小;进行了半导体激光器热特性建模与仿真,发现温度升高会使半导体激光器阈值电流增大;利用半导体激光器加速退化试验平台进行了半导体激光器加速退化试验。仿真与试验结果证明:温度升高会加剧半导体激光器腔面退化,而对有源区退化无显著影响。上述结论对进一步完善半导体激光器温度-退化仿真模型,研究温度对半导体激光器退化的作用机理和防护措施有积极作用。  相似文献   
369.
为满足导弹拦截机动目标时交会角约束和有限时间收敛的需求,建立了考虑弹体一阶动态特性的制导模型。把目标加速度视为有界外界干扰,同时结合非线性反步设计法中的动态面法,设计一种考虑弹体动态延迟的非奇异滑模制导律,并且证明了基于Lyapunov稳定性理论制导系统状态可渐进收敛到零。在所设计的制导律下,对单侧机动的低空高速目标进行仿真。仿真结果表明所设计的非奇异制导律可以有效降低弹体动态延迟带来的影响,而且具有较低的脱靶量与交会角误差;与考虑弹体动态特性和交会角约束的最优导引律相比,其具有更高的制导精度。  相似文献   
370.
为解决卫星上反作用飞轮存在安装偏差、故障及外部干扰情况下的姿态控制问题,提出了一种基于迭代学习观测器的姿态容错控制方法。该方法通过设计迭代学习观测器,以较小的计算量实现对执行机构发生的故障以及安装偏差进行精确的估计。并利用观测器的观测结果设计滑模控制器,使处于外部干扰条件下的卫星系统在执行机构发生故障的情况下可以快速稳定地完成姿态机动任务。进一步基于Lyapunov稳定性定理证明了迭代学习观测器及控制器的全局渐近稳定性。针对反作用飞轮存在不确定性及故障的情况下进行仿真,仿真结果表明,与同类容错控制方法相比,所提方法可以更加快速精确地对故障进行估计并完成姿态控制。  相似文献   
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