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241.
从阐述魔球操作对目标瞄准的实现机制入手,分析了数据采集系统的总体结构及采集系统的硬件设计和软件设计思想.实现了对飞机魔球信号的实时采集,并对采集结果进行仿真分析,从而推导出不同相关武器种类、目标与弹轴不同夹角、不同目标距离、不同工作状态下魔球信号的变化规律.  相似文献   
242.
The mitigation of blast shock with water has broad application prospects. Understanding the mitigation effects on the reflected overpressure of the explosion shock with water surrounding an explosive in a confined space is of great significance for military explosives safety applications. To estimate the effects of the parameters on the reflected overpressure of blasted shock wave, a series of experiments were carried out in confined containers with spherical explosives immersed in a certain thickness of water, and numerical simulations were conducted to explore the corresponding mechanisms. The results reveal that the reflected overpressure is abnormally aggravated at a small scaled distance. This aggravation is due to the high impulse of the bulk accelerated water shell converted from the explosion. With increasing scaled distance, the energy will be gradually dissipated. The mitigation effects will appear with the dispersed water phase front impacting at a larger scaled distance, except in the case of a dense water phase state. A critical scaled distance range of 0.7—0.8 m/kg1/3 for effective mitigation was found. It is suggested that the scaled distance of space walls should be larger than the critical value for a certain water-to-explosive weight ratio range (5—20).  相似文献   
243.
For the case that two pursuers intercept an evasive target, the cooperative strategies and state estimation methods taken by pursuers can seriously affect the guidance accuracy for the target, which performs a bang For the case that two pursuers intercept an evasive target, the cooperative strategies and state estimation methods taken by pursuers can seriously affect the guidance accuracy for the target, which performs a bang-bang evasive maneuver with a random switching time. Combined Fast multiple model adaptive estimation (Fast MMAE) algorithm, the cooperative guidance law takes detection configuration affecting the accuracy of interception into consideration. Introduced the detection error model related to the line-of-sight (LOS) separation angle of two interceptors, an optimal cooperative guidance law solving the optimization problem is designed to modulate the LOS separation angle to reduce the estimation error and improve the interception performance. Due to the uncertainty of the target bang-bang maneuver switching time and the effective fitting of its multi-modal motion, Fast MMAE is introduced to identify its maneuver switching time and estimate the acceleration of the target to track and intercept the target accurately. The designed cooperative optimal guidance law with Fast MMAE has better estimation ability and interception performance than the traditional guidance law and estimation method via Monte Carlo simulation.  相似文献   
244.
This study investigates and quantifies some possible sources affecting the position of impact points of small caliber spin-stabilized projectiles (such as 12.7 mm bullets). A comparative experiment utilizing the control variable method was designed to figure out the influence of tiny eccentric centroids on the projectiles. The study critically analyzes data obtained from characteristic parameter measurements and precision trials. It also combines Sobol's algorithm with an artificial intelligence algorithm—Adaptive Neuro-Fuzzy Inference Systems (ANFIS)—in order to conduct global sensitivity analysis and determine which parameters were most influential. The results indicate that the impact points of projectiles with an entry angle of 0° deflected to the left to that of projectiles with an entry angle of 90°. The difference of the mean coordinates of impact points was about 12.61 cm at a target range of 200 m. Variance analysis indicated that the entry angle — i.e. the initial position of mass eccentricity — had a notable influence. After global sensitivity analysis, the significance of the effect of mass eccentricity was confirmed again and the most influential factors were determined to be the axial moment and transverse moment of inertia (Izz Iyy), the mass of a projectile (m), the distance between nose and center of mass along the symmetry axis for a projectile (Lm), and the eccentric distance of the centroid (Lr). The results imply that the control scheme by means of modifying mass center (moving mass or mass eccentricity) is promising for designing small-caliber spin-stabilized projectiles.  相似文献   
245.
Liquid-filled compartment structure consists of a bulk steel plate with matrix blind holes which are filled with liquid and a steel front plate to seal up the liquid with rings and bolts.The liquid-filled compart-ment structure can resist the shaped charge warhead effectively.This paper presents experimental and theoretical investigations of the penetration ability of the residual shaped charge jet emerging from the liquid-filled compartment structure after the penetration process at different impact angles.On the basis of shock wave propagation theory,the influence of the liquid-filled compartment structure on jet sta-bility is analysed.The interferences of the liquid backflow caused by a reflected shock wave and a back plate on jet stability under different impact angles are also examined.In addition,the range of the disturbed velocity segments of the jet at different impact angles and the penetration ability of the re-sidual jet are obtained.A theoretical model is validated against the experimental penetration depths.  相似文献   
246.
通过对空间兵棋和传统兵棋特点的详细对比和分析,针对空间兵棋在量化裁决中的特点提出了模块化的横向分类型纵向分步骤量化裁决模型.针对空间兵棋在概率裁决中影响因素多种多样的特点,提出了三维概率裁决表概率裁决模型.并通过具体裁决算例,验证了横向分类型纵向分步骤模型的有效性和三维概率裁决表模型的合理性.  相似文献   
247.
延期传扩爆装置作为一种新型组合式火工品,其性能对战斗部最终发挥作战效能起到至关重要的作用。本文从建立影响导爆索爆速的故障树入手,分析了原材料、拉索模具、加工工艺、测试方法等因素对爆速的影响,解决了产品延期时间偏高的质量问题。  相似文献   
248.
航空用复合材料结构件无损检测技术分析   总被引:4,自引:0,他引:4  
本文通过对航空复合材料结构件缺陷和损伤特点的分析,介绍可应用于航空复合材料结构缺陷包括目视检查法、声阻法、射线检测技术、超声检测技术、声-超声技术、涡流检测技术、微波检测技术在内的无损检测技术。并对无损检测技术的技术关键进行剖析,展望了无损检测技术的未来发展。  相似文献   
249.
提高领导军事斗争准备的本领,抓紧做好军事斗争准备是我军各级党组织面临的最重要、最现实、最紧迫的战略任务。正确认识各级党组织的根本领导职能,正确把握军事斗争准备的内涵和定位,是增强各级党组织抓军事斗争准备自觉性、减少盲目性的必要前提。提高各级党组织抓军事斗争准备能力要重视的是:它涉及到诸多因素,必须着力研究和解决制约能力提高的各种问题;它是一个复杂的系统工程,既需要各级党组织自身的努力,又需要多方面形成合力。  相似文献   
250.
随着下一代可重复使用飞行器,特别是单级入轨飞行器的研究,很多新技术都得到发展,三组元混合燃烧技术就是其中之一。本文中通过进行热力计算来对比、讨论三组元发动机与两组元发动机在理论比冲上的差异,分析三组元发动机的可行性。  相似文献   
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