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961.
基于区域实际大气的红外制导波段目标背景对比度变化特性数值计算 总被引:1,自引:0,他引:1
红外制导武器对目标的发现、识别和跟踪主要依据目标与背景的红外辐射特性及其对比特性,目标背景对比特性研究是红外制导武器研制过程中的必要环节。依据目标背景对比度定义,采用基于既定区域实际观测大气数据构建大气参数廓线并嵌入成熟、通用的大气辐射传输模型计算的方式,探讨了红外波段实际大气目标背景对比度变化特征,及其与标准大气下的目标背景对比度差异。结果表明,影响目标背景对比度的主要因素为大气透过率,实际大气目标背景对比度与标准大气的存在一定偏差,偏差与季节和波段均有关,可直接影响到红外波段实际应用中的目标识别能力。 相似文献
962.
林晓莉 《中国人民武装警察部队学院学报》2010,26(6):56-58
20世纪80年代兴起的农村工业小企业,为改革开放初期的经济发展发挥了显著作用,但由于在经济建设及发展过程中缺乏科学有效规划和消防安全管理,遗留了诸多火灾隐患。以福州市仓山区为例,深入分析了农村工业小企业存在的火灾隐患问题,并从火灾隐患的消防技术整改和强化消防管理两个方面提出具体对策。 相似文献
963.
水面靶标为反舰武器海上飞行试验提供水面模拟舰船目标。介绍了红外成像靶的功能和技术指标,详细给出了舰船红外成像模拟实现的总体设计方案、硬件和软件实现方式。海上测试结果表明,这种靶标能够较好地实现舰船红外热像模拟,在海上试验的实际应用中取得了预期效果。 相似文献
964.
利用双波段IRST系统测到的目标双波段红外辐射信息,推导出目标的伪距离量测信息,使得单站IRST系统变为可观测系统;在此基础上,构建了伪量测方程,采用改进的"当前"统计模型和基于最小偏度单形采样策略的UKF算法,提出了一种基于双波段红外辐射信息的IRST机动目标跟踪算法。理论分析与仿真结果表明,该算法能够有效地跟踪机动目标,具有良好的实际应用价值。 相似文献
965.
《防务技术》2020,16(2):493-501
In order to improve the underwater acoustic target strength of corner reflectors, according to the principle of acoustic impedance mismatch of the boundary layer, the method of using air cavity to increase the underwater acoustic target strength of corner reflectors is proposed. The acoustic reflection coefficients of underwater air layer and single layer metal sheet are calculated and compared. The results show that the reflection coefficient of single layer metal sheet is greatly affected by frequency and incidence angle, and the reflection coefficient of air layer in water is large and little affected by frequency and incidence angle. On this basis, a new kind of airfilled cavity corner reflector is designed. The acoustic scattering characteristics of underwater airfilled cavity corner reflector are calculated cumulatively, and the results are compared with the monolayer metal sheet corner reflector. The simulation results show that the acoustic reflection effect of the airfilled cavity corner reflector is better. In order to verify the correctness of the method, the test was carried out in the silencing tank. The experimental results show that the simulation results are in good agreement with the experimental results, and the airfilled cavity can improve on acoustic reflection performance of the underwater corner reflector. 相似文献
966.
从防空兵作战指挥的实际需求出发,利用概率论和防空作战运筹理论,描述了集中、分散、混合和平行等射击指挥方式的概念、特点及其相互关系,论述了射击指挥方式定量分析的基本方法、主要依据和指标,建立了基于群抗击效率的评估模型,在对多种射击指挥方式进行定量比较的基础上,揭示了射击指挥中具有普遍意义的、潜在的实用规则. 相似文献
967.
968.
辐射源数据往往不完整或不确定,因此应用模糊推理实现了辐射源和目标平台的识别.将辐射源特征转换为由模糊集及隶属度函数表征的参数,再通过与数据库中的辐射源数据进行模糊匹配来判断辐射源的类型,实现了雷达辐射源的被动识别方法.进一步通过识别出目标平台上所装备的雷达辐射源的参数值,利用模糊推理,推断出目标平台的类型.试验结果表明:模糊推理的算法是切实可行的,在对模拟数据加入的噪声不超过一定限制的情况下,对于数据库已有的目标能够达到较高的目标识别率. 相似文献
969.
《防务技术》2020,16(3):737-746
Infrared target intrusion detection has significant applications in the fields of military defence and intelligent warning. In view of the characteristics of intrusion targets as well as inspection difficulties, an infrared target intrusion detection algorithm based on feature fusion and enhancement was proposed. This algorithm combines static target mode analysis and dynamic multi-frame correlation detection to extract infrared target features at different levels. Among them, LBP texture analysis can be used to effectively identify the posterior feature patterns which have been contained in the target library, while motion frame difference method can detect the moving regions of the image, improve the integrity of target regions such as camouflage, sheltering and deformation. In order to integrate the advantages of the two methods, the enhanced convolutional neural network was designed and the feature images obtained by the two methods were fused and enhanced. The enhancement module of the network strengthened and screened the targets, and realized the background suppression of infrared images. Based on the experiments, the effect of the proposed method and the comparison method on the background suppression and detection performance was evaluated, and the results showed that the SCRG and BSF values of the method in this paper had a better performance in multiple data sets, and it’s detection performance was far better than the comparison algorithm. The experiment results indicated that, compared with traditional infrared target detection methods, the proposed method could detect the infrared invasion target more accurately, and suppress the background noise more effectively. 相似文献
970.
Siniša Malešević 《Small Wars & Insurgencies》2018,29(4):735-753
This article explores the dynamics of social cohesion on the frontline. It attempts to show how micro-level solidarities largely depend on macro level organisational processes. I argue that frontline social cohesion is often the product of social development linked with the organisational structure. This general argument is applied to the case studies of two armed forces involved in the 1991–1995 Wars of Yugoslav Succession – the Croatian Army (HV) and the Bosnian Serb Army (VRS). Drawing on in-depth interviews with the former combatants I show how HV social cohesion played an important role in winning the war and how these networks of micro-level solidarity were shaped by long term organisational development. 相似文献