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191.
192.
根据舰舰导弹攻击时使用雷达方式的不同,可将舰舰导弹攻击主要归结为三种样式,即其他兵力引导攻击样式、被动雷达攻击样式和主动雷达发波攻击样式。衡量各个攻击样式优劣主要考虑攻击的隐蔽性、命中率和发挥武器最大射程等三个因素。为此建立舰舰导弹攻击样式选择问题的递阶层次结构模型,从衡量各攻击样式优劣的三个主要因素出发,对模型进行了分析。最后得出了以其他兵力引导攻击为最佳攻击样式的结论。 相似文献
193.
机动目标建模及机动检测算法 总被引:1,自引:0,他引:1
为解决机动目标跟踪问题,建立了非机动(匀速直线运动)和机动目标当前统计两种动态模型,并对机动目标当前统计模型的输入控制的估计进行了适当改进.同时对非机动模型的观测残差和机动模型的输入估计进行检验,以便准确检测目标机动. 相似文献
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195.
This article describes a heuristic and two exact algorithms for several classes of vehicle routing problems defined on tree networks. These include capacitated and time‐constrained vehicle routing problems. One of the exact algorithms is based on the computation of bin packing lower bounds. The other uses column generation. The first algorithm performs better on problems containing small customer demands and in which all vehicles are identical. Otherwise, the second algorithm is more powerful and more versatile. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 75–89, 1999 相似文献
196.
美军装备试验鉴定发展历程分析及启示 总被引:1,自引:0,他引:1
美军装备试验经历近百年的发展,已形成较为成熟的试验鉴定模式和管理评价体制,试验鉴定能力也处于世界领先水平.美军在装备发展历程中的经验做法十分值得学习和借鉴.本文分析了美军装备试验鉴定发展历程和特点,研究了其试验组织结构的科学构成和运行机制,归纳总结了美军装备试验发展的客观规律和科学经验.在此基础上,得到了顺应装备发展趋... 相似文献
197.
将组合电路故障模拟的一些加速技术推广到时序电路故障模拟中,提出并实现了一个功能块级的基于测试码并行的同步时序电路故障模拟方法,对部分ISCAS89 Benchmark电路的模拟结果表明,该故障模拟方法有较好的性能. 相似文献
198.
为了有效发挥指挥控制(Command and Control, C2)组织集中式决策和协作式决策的决策优势,对具有决策权限动态变化能力的Holonic-C2组织的决策分配问题进行研究。针对群决策中专家固定权重的主观性太强的缺点,提出基于专家权威性和意见一致性相结合的专家组选择方法,提高了决策分配过程中多属性决策的客观合理性;针对决策分配的动态演化问题,提出基于多阶段决策的决策模式演化机制,在考虑属性前后阶段的变化的基础上,给出相邻阶段决策模式跃迁方法。仿真结果表明,所提方法能够给出相对客观的决策模式的优劣排序以及多阶段的演化路线,从而证明了方法的可行性和有效性。 相似文献
199.
《防务技术》2020,16(2):362-373
An increase in the use of the gun barrel will cause wear of the inner wall, which reduces the muzzle velocity and the spin rate of the projectile. The off-bore flight attitude and trajectory of the projectile also change, affecting the shooting power and the accuracy. Exterior ballistic data of a high-speed spinning projectile are required to study the performance change. Therefore, based on the barrel's accelerated life test, the whole process of projectile shooting is reproduced using numerical simulation technology, and key information on the ballistic performance change at each shooting stage are acquired. Studies have shown that in the later stages of barrel shooting, the accuracy of shooting has not decreased significantly. However, it is found that the angle of attack of the projectile increases as the wear of the barrel increases. The maximum angle of attack reaches 0.106 rad when the number of shots reaches 4300. Meanwhile, elliptical bullet hole has appeared on the target at this shooting stage. Through combining external ballistic theory with simulation results, the primary reason of this phenomenon is found to be a significant decrease in the muzzle spin rate of the projectile. At the end of the barrel life, the projectile muzzle spin rate is 57.5% lower than that of a barrel without wear. 相似文献
200.
《防务技术》2020,16(2):392-400
The optocoupler is a weak link in the inertial navigation platform of a kind of guided munitions. It is necessary to use accelerated storage test to verify the storage life of long storage products. Especially for small sample products, it is very important to obtain prior information for the design and implementation of accelerated degradation test. In this paper, the optocoupler failure mechanism verification test is designed and the experimental results are analyzed and the prior information is obtained. The results show that optocouplers have two failure modes, one is sudden failure and the other is degradation failure; the maximum temperature stress of optocoupler can't exceed 140 °C; the increase of leakage current of optocoupler is caused by movable ions contaminating the LED chip. The surface leakage current is proportional to the adsorption amount. The increase of leakage current makes p-n junction tunneling effect occur which LEDs the failure of the optocoupler. The lifetime distribution model of the optocoupler is determined by the failure physics. The lifetime of the optocoupler is subject to the lognormal distribution. The degeneracy orbit of the optocoupler leakage current is described by a power law model. The estimated values of the orbital parameters are initially calculated and the parameters of its life distribution function are deduced. The above information lays a good foundation for the optimization design and data processing of the accelerated degradation experiment. 相似文献