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161.
考虑地球非球形引力摄动影响的自由段弹道解析解 总被引：1，自引：0，他引：1
常晓华 《国防科技大学学报》2018,40(4):80-86
针对地球非球形引力摄动影响下的自由段弹道快速计算问题,在非正交坐标系内建立考虑J2项摄动的地球引力作用下的运动微分方程,在轨道坐标系内建立扰动引力作用下的运动微分方程,并计算天向扰动引力加速度对应的质量偏差,进而通过椭圆轨道以修正J2项摄动运动微分方程;在建立上述运动微分方程解析解的基础上,给出了地心坐标系内弹道飞行器位置和绝对速度的表达式,从而提出了J2项摄动引力和扰动引力作用下的自由段弹道解析计算方法。仿真分析表明:该方法具有较高的计算效率,落点位置偏差小于20 m,满足弹道飞行器高精度实时制导、轨迹预测等应用需求。 相似文献
162.
设计并进行了7.62mm穿甲子弹侵彻陶瓷/低碳钢复合靶板的弹道试验,得到了极限速度及陶瓷锥底部半径等数据。分析了锥底半径与入射速度、面板及背板厚度的关系,着重分析了偏心入射时靶板的抗弹机理。结果表明:陶瓷锥可分为破碎区和粉碎区,粉碎区半径约为面板厚度与弹丸半径之和;当弹着点距离陶瓷面板边缘大于5mm时,靶板的抗弹性能变化不大,而弹着点位于距陶瓷面板边缘小于5mm的板边区时,抗弹性能明显降低,靶板的有效防护面积应扣除板边区。 相似文献
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The dielectric constant (DC) is one of the key properties for detection of threat materials such as Improvised Explosive Devices (IEDs). In the present paper, the density functional theory (DFT) as well as ab-initio approaches are used to explore effective methods to predict dielectric constants of a series of 12 energetic materials (EMs) for which experimental data needed to experimentally determine the dielectric constant (refractive indices) are available. These include military grades energetic materials, nitro and peroxide compounds, and the widely used nitroglycerin. Ab-initio and DFT calculations are conducted. In order to calculate dielectric constant values of materials, potential DFT functional combined with basis sets are considered for testing. Accuracy of the calculations are compared to experimental data listed in the scientific literature, and time required for calculations are both evaluated and discussed. The best functional/basis set combinations among those tested are CAM-B3LYP and AUG-cc-pVDZm, which provide great results, with accuracy deviations below 5% when calculated results are compared to experimental data. 相似文献
165.
《防务技术》2019,15(3):319-325
Nanothermites (metal oxide/metal) can offer tremendously exothermic self sustained reactions. CuO is one of the most effective oxidizers for naonothermite applications. This study reports on two prospectives for the manufacture of CuO nanoparticles. Colloidal CuO particles of 15 nm particle size were developed using hydrothermal synthesis technique. Multiwalled carbon nanotubes (MWCNTs) with surface are 700 m2/g was employed as a substrate for synthesis of CuO-coated MWCNTs using electroless plating. On the other hand, aluminium particles with combustion heat of 32000 J/g is of interest as high energy density material. The impact of stoichiometric nanothermite particles (CuO/Al & Cuo-coated MWCNTs/Al) on shock wave strength of Al/TNT nanocomposite was evaluated using ballistic mortar test. While CuO-coated MWCNTs decreased the shock wave strength by 15%; colloidal CuO enhanced the shock wave strength by 30%. The superior performance of colloidal CuO particles was correlated to their steric stabilization with employed organic solvent. This is the first time ever to report on fabrication, isolation, and integration of stablilized colloidal nanothermite particles into energetic matrix where intimate mixing between oxidizer and metal fuel could be achieved. 相似文献
166.
ABSTRACTResearchers have recently proposed a new approach to nuclear-arms-control verification, dubbed “deferred verification.” The concept forgoes inspections at sensitive nuclear sites and of nuclear weapons or components in classified form. To implement this concept, a state first divides its nuclear program into a closed segment and an open segment. The total fissile-material inventory in the closed segment, which includes the weapon complex, is known and declared with very high accuracy. Essentially no inspections take place in the closed segment. In contrast, inspectors have access to the open segment, which includes in particular the civilian nuclear sector. The fissile-material inventory in the open segment is known with less accuracy, but uncertainties can be reduced over time using nuclear-archaeology methods. Deferred verification relies primarily on established safeguards techniques and avoids many unresolved verification challenges, such as the need for information barriers for warhead confirmation measurements. At the same time, deferred verification faces some unique challenges. Here, we explore some of these challenges and offer possible solutions; to do so, we examine possible noncompliance strategies in which a state would seek to withhold a higher-than-declared inventory. 相似文献
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169.
惯性弹体运动预测建模 总被引：1，自引：0，他引：1
基于弹道方程的理论建立了来袭惯性弹体的运动预测模型和识别模型,一方面为防空作战从战术前沿拓展到中程以上拦截提供模型基础,另一方面为前沿防空中拦截榴弹、火箭弹类小型目标提供出精度更高的预测模型。最后,研究中成功给出了弹体运动状态预测及识别的计算结果,并得到了真实射表的验证。模型普遍适用于所有来袭惯性弹体的运动。 相似文献
170.
应急物流保障与军地物流一体化研究 总被引：2，自引：0，他引：2
应急物流与军事物流都是在特殊条件下发生的物流活动,研究应急物流与军地物流一体化对于促进军事物流的发展具有重要意义.简述了应急物流的基本问题,分析了实现应急物流保障的基本条件:需要完善的应急法律体系、功能健全的应急指挥机构以及高效可靠的应急物流保障平台,阐明了军地物流一体化与应急物流的区别、军地物流一体化的重要作用,并对军地物流一体化下的应急物流保障模式进行了研究. 相似文献