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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
434.
文中介绍了IRM-PC机上多功能仿真软件GASP/PC的开发,叙述了GASP/PC仿真语言的形成以及对于连续、离散和复合仿真模型的GASP/PC语言的结构与仿真方法。 相似文献
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子母弹作为一种面杀伤武器,在遂行封锁敌机场作战任务时可发挥有效作用。本文以子母弹主要技战术指标为研究对象,首先给出基于最小起飞窗口的跑道封锁判断方法和基于蒙特卡洛仿真的机场跑道封锁概率估算模型,然后研究了母弹圆概率误差、子炸弹抛撒半径、数量以及毁伤半径等主要弹药参数对机场跑道封锁率曲线的影响。结果表明:跑道封锁率对母弹圆概率误差和抛撒半径的变化较为敏感,通过优化上述参数可以显著降低子母弹耗弹量,提高封锁效率;相比之下,单枚母弹内子炸弹数量和单枚子炸弹毁伤半径在一定范围内变动时对机场封锁率影响较小。本仿真研究的结果可为封锁机场作战时弹药选取、耗弹量测算提供科学依据,并对子母弹后续型号改进提供有效建议。 相似文献
437.
《防务技术》2020,16(1):96-106
The numerical simulation of a blast wave of a multilayer composite charge is investigated. A calculation model of the near-field explosion and far-field propagation of the shock wave of a composite charge is established using the AUTODYN finite element program. Results of the near-field and far-field calculations of the shock wave respectively converge at cell sizes of 0.25–0.5 cm and 1–3 cm. The Euler––flux-corrected transport solver is found to be suitable for the far-field calculation after mapping. A numerical simulation is conducted to study the formation, propagation, and interaction of the shock wave of the composite charge for different initiation modes. It is found that the initiation mode obviously affects the shock-wave waveform and pressure distribution of the composite charge. Additionally, it is found that the area of the overpressure distribution is greatest for internal and external simultaneous initiation, and the peak pressure of the shock wave exponentially decays, fitting the calculation formula of the peak overpressure attenuation under different initiation modes, which is obtained and verified by experiment. The difference between numerical and experimental results is less than 10%, and the peak overpressure of both internal and external initiation is 56.12% higher than that of central single-point initiation. 相似文献
438.
《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
439.
在对虚拟现实训练系统分类论述的基础上,探讨了虚拟现实技术在消防训练中的应用及优势,阐述了该领域在国内外的研究现状和发展前景,并指出了有待进一步研究的问题。 相似文献
440.
Michael C. Fu 《海军后勤学研究》2008,55(8):723-736
Derivatives (or gradients) are important for both sensitivity analysis and optimization, and in simulation models, these can often be estimated efficiently using various methods other than brute‐force finite differences. This article briefly summarizes the main approaches and discusses areas in which the approaches can most fruitfully be applied: queueing, inventory, and finance. In finance, the focus is on derivatives of another sort. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008 相似文献