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排序方式: 共有102条查询结果,搜索用时 15 毫秒
31.
研制了一种激光编码记录装置,通过接收目标漫反射激光信号,模拟弹上部分控制系统工作产生两路特征信号,并采用边沿特征时间标识记录方法对特征信号进行数据记录.该装置在数据储存量显著减少的情况下能保持高精度的时间记录,真实记录目标漫反射激光接收过程中的激光编码等信息,有利于对末制导炮弹射击过程和结果进行关联分析. 相似文献
32.
船用反应堆堆芯物理计算软件包的研制 总被引:3,自引:0,他引:3
基于船用反应堆结构特点与运行方式 ,通过对核电站大型机版堆芯物理计算软件的移植与修改 ,研制了微机版船用反应堆堆芯物理计算软件包 .可用于船用反应堆燃料组件参数及堆芯三维细网临界与燃耗的计算研究 相似文献
33.
陈先福 《国防科技大学学报》1994,16(1):23-31
本文分析了跟踪干扰对跳频系统中码跟踪环性能的影响。它使参考码与接收码之间的相位误差均值偏移,相位误差方差增大,环路失锁慨率增加,以及间接地使误码率上升。 相似文献
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针对广义信道下伪码测距偏差与各部分通道测距偏差叠加值的等效性问题,研究星地叠加通道和部分通道特性对伪码测距偏差的影响,并对实际通道中伪距"分层"现象的成因展开分析。通道非理想特性会对导航信号伪码跟踪性能产生影响,综合考虑星地两端通道的非理想特性,通过对导航信号伪码跟踪函数和不同类型通道建模,研究了星地叠加通道和部分通道特性对伪码测距偏差的影响。结合几类典型星地非理想通道,利用软件接收机展开仿真验证。通过分析几类典型通道对伪码测距偏差的影响,解释了零基线双差观测量中伪距"分层"现象的成因。文中模型与相关分析方法可用于解释相关信号质量问题,并指导接收机通道的最优化设计。 相似文献
36.
在高精度伪码测距系统中,高功率放大器(HPA)是信号发射链路的重要组成部分,HPA会对发射信号引入非线性失真,进而恶化系统的伪码测距性能.通过理论推导和数值分析的方法,研究HPA的非线性特性对高精度伪码测距误差的影响,给出非线性放大条件下,伪码跟踪误差与放大器类型、放大器输出回退(OBO)、扩频码形参数等的定量关系.研究结果对工程上HPA的选择、功率余量的保留、基带扩频码形的设计等具有重要的参考价值. 相似文献
37.
This paper models transnational terrorism as a three‐way strategic interaction involving a government that faces armed opposition at home, which may spill over in the form of acts of terrorism by the state's opponents against the government's external sponsor. The external sponsor also utilises deterrence against potential terrorists, which only lowers terrorism if terrorists are not intrinsically motivated by a deep‐seated sense of humiliation. The model highlights the importance of intrinsic motivation. A rise in the external power's preference for deterrence against terrorism may backfire in these circumstances. Increases in the government's military efficiency against the rebels, who are also terrorists against the government's sponsor, raises overall levels of violence. 相似文献
38.
《防务技术》2022,18(12):2181-2189
An adverse effect resulting from explosive mine blasts is the production of toxic nitrogen oxides (NO and NO2) and carbon monoxide (CO). The empirical measurements of the concentration of toxic gases showed that it depends not only on the composition of an explosive and properties of its ingredients but also on several other parameters, such as volume of blasting chamber, explosive charge mass and design, confinement characteristics, surrounding atmosphere, etc. That explains why measured concentrations of toxic gases reported in literature significantly differ.In this paper, we discuss the possibility of theoretical prediction of the concentration of toxic gases by thermochemical equilibrium calculation applying two models: ideal detonation model and deflagration model. It can be demonstrated that thermochemical calculations can provide a good estimation of the measured concentrations and reproduce experimentally obtained effects of additives on the production of toxic gases. It was also found that the ideal detonation model applies to heavily confined explosive charges, while the deflagration model is more suitable for low detonation velocity explosives with light confinement. 相似文献
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40.
Antonio Giustozzi 《Small Wars & Insurgencies》2014,25(2):284-296
The Taliban's ‘code of conduct’, which lists rules of discipline for the fighters, has been widely discussed, but do the Taliban try to implement it? This article discusses the structures that the Taliban have put in place for this purpose and their evolution over the years. It assesses that while the Taliban's ‘military justice’ system is still work in progress, the fact that it has attracted a significant investment in human resources bears witness to a serious intent of the leadership. However, the Taliban's concern with the behaviour of their fighting force is driven by their own political calculus, not by any sympathy for the international law of conflict. 相似文献