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排序方式: 共有221条查询结果,搜索用时 15 毫秒
71.
故障在线诊分析了测试点电压增量与故障子网络空间的关系,提出了将测试点电压增量投影到子网络空间定位故障子网络的方法.该方法仅需一次测试结果,且不依赖于子网络内的结构和参数,故可用于"黑箱”子网络的故障诊断. 相似文献
72.
利用登月飞行器的级间组合设计方法对载人登月飞行器的构造进行设计,在级间方案的论证中分析了不同组装模式对运载火箭能力的需求,建立了航天员和机器人联合探测的载人登月方案。级间组合方法可为应转移飞行器和登月飞行器设计提供另一种思路,根据飞行器级间的不同组合方式对登月飞行器的质量规模进行了初步估算,并对比了不同飞行方案对运载火箭能力的需求,研究可为我国首次载人登月任务方案提供参考。 相似文献
73.
Michael Raber 《Arms and Armour》2017,14(1):70-98
The U.S. Armory in Springfield, Massachusetts, rarely appears in Civil War histories except perhaps as an unexplained statistical wonder. By late 1863, the Armory was the largest single supplier of rifles to Union forces. Springfield Armory workers out-produced over thirty American contractors, making more Army rifles at less cost while providing contractors with gauges, inspectors, and models, even though there were significant wartime private-sector mechanical innovations. This article identifies and explains the factors in the Armory’s success, provides context on contemporary American arms production and rifle models, and argues that the Armory’s methods and performance were among the first if not the first example of mass production in American small arms manufacture. The relative brevity of the Civil War episode, and the fact that it was not repeated in any comparable way at the Armory until World War II, has obscured its significance in American manufacturing history. 相似文献
74.
《防务技术》2022,18(11):1979-1999
A quasi-isentropic study on the process of driving a cylinder with aluminized explosives was carried out to examine the influence of the aluminum (Al) reaction rate on cylinder expansion and the physical parameters of the detonation products. Based on the proposed quasi-isentropic hypothesis and relevant isentropic theories, the characteristic lines of aluminized explosives driving a cylinder were analyzed, and a quasi-isentropic model was established. This model includes the variation of the cylinder wall velocity and the physical parameters of the detonation products with the Al reaction degree. Using previously reported experimental results, the quasi-isentropic model was verified to be applicative and accurate. This model was used to calculate the physical parameters for cylinder experiments with aluminized cyclotrimethylenetrinitramine explosives with 15.0 % and 30.0 % Al content. The results show that this quasi-isentropic model can be used not only to calculate the cylinder expansion rule or Al reaction degree, but also to calculate the physical parameters of the detonation products in the process of cylinder expansion. For explosives with 15.0 % and 30.0 % Al, 24.3 % and 18.5 % of the Al was found to have reacted at 33.9 μs and 34.0 μs, respectively. The difference in Al content results in different reaction intensity, occurrence time, and duration of two forms of reaction (diffusion and kinetic) between the Al powder and the detonation products; the post-detonation burning reaction between the Al powder and the detonation products prolongs the positive pressure action time, resulting in a continuous rise in temperature after detonation. 相似文献
75.
靶场在进行智能鱼雷鉴定试验任务时,实时准确地检测出鱼雷自导信号的频率成分是靶标信号处理中的重要环节,谱线比值法便是靶标进行信号处理时检测信号频率的一种有效方法。本文介绍了谱线比值法的基本原理,针对目前鱼雷自导信号特点,对该方法提出了改进方案并进行了仿真。仿真结果表明,经改进的谱线比值法能够满足靶标检测复杂鱼雷自导信号体制下信号频率的使用要求。 相似文献
76.
张强 《中国人民武装警察部队学院学报》2014,(11):43-47
分析开展反恐怖斗争群众工作存在的问题,包括政府各职能部门协调配合不够,没有形成合力;认识存在偏差,工作效果不明显;宣传工作开展不够;基础工作不扎实,综合治理机制不健全;对特殊人群关注和服务不够。从加强组织领导,联系了解群众,宣传教育工作,发动组织群众,服务群众五个方面提出对策。 相似文献
77.
Some of the most active arms races are taking place between developed and less developed countries. The inability of less developed countries to compete financially, as well as technologically, with developed countries may be forcing the former to acquire terror weapons (TWP). The Iran–Iraq war in the 1980s and the events of 9/11 proved that the use of TWP is no longer a mere threat; there are several organizations and countries that will not hesitate to use them. This study develops a model of resource allocation in an arms race between a developed country that is characterized by state‐of‐the‐art technology and high GDP, and a less developed country whose technological capability and GDP are much lower. The model is used to predict the optimal mix of weapons of the two countries that are engaged in the arms race. Applying the model to the arms race between Israel and Syria demonstrates its use. 相似文献
78.
ANDILE SOKOMANI 《African Security Review》2013,22(4):81-90
“Lack of money is the root of all evil” George Bernard Shaw In a environment where party financing, private funding in particular, is generally a laissez-faire business, as in most Southern African countries, there is the real risk that interest groups and wealthy individuals will buy influence in political parties and in so doing erode public confidence in the political system. Because they are neither open to public scrutiny nor subject to any legislative restraints, huge private donations can, and often do, come with strings attached. This lack of transparency and openness, as well as mechanisms to prevent it, provides ample ground for influence peddling, where those who pay the piper call the tune. Left unchecked, this party funding scenario will continue to be a serious indictment of the region's democratisation projects, crippling democracy and stunting economic development. This article consid 相似文献
79.
研究了利用小推力器进行航天器姿态控制问题。从理论上推导了在给定姿态控制精度、小推力器参数以及倾斜开关曲线参数的前提下,能够形成理想极限环控制效果的充分必要条件。对相关文献中倾斜开关曲线设计方法不能形成理想极限环的情况进行了理论分析,提出了一种新的基于倾斜开关曲线的准极限环控制方法,并推导了其控制精度。研究对于航天器应用小推力器实现高精度姿态控制具有较大的工程应用价值。 相似文献
80.
张辉 《中国人民武装警察部队学院学报》2004,20(1):78-80
边防民族学是民族学与边防工作结合起来的一门学问,是以边境地区少数民族为研究对象,将民族学的知识和有关研究成果运用于边防群众工作和民族工作,以维护边境安全与稳定的新的应用性学科。边防民族学具有应用性、前沿性、前瞻性的特点,边防专业建立和开设边防民族学是十分迫切、必要和可行的。 相似文献