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241.
针对典型的导弹弹道仿真,通过对反导导弹的几种备选制导律进行了参数调试和数字仿真,设计了初、中制导方案,通过数字仿真给出了弹道规划,明确了允许的发射条件。同时,分析了各方案主要的制导信息误差及其影响,针对高斯噪声误差模型提出了制导信息误差指标。最终确定了较优制导方案。该方案经数字仿真验证具有较优的攻击区性能,攻击区较大、发射条件约束较为宽松,以当前的技术水平有望实现。  相似文献   
242.
This paper proposes a skewness correction (SC) method for constructing the and R control charts for skewed process distributions. Their asymmetric control limits (about the central line) are based on the degree of skewness estimated from the subgroups, and no parameter assumptions are made on the form of process distribution. These charts are simply adjustments of the conventional Shewhart control charts. Moreover, the chart is almost the same as the Shewhart chart if the process distribution is known to be symmetrical. The new charts are compared with the Shewhart charts and weighted variance (WV) control charts. When the process distribution is in some neighborhood of Weibull, lognormal, Burr or binomial family, simulation shows that the SC control charts have Type I risk (i.e., probability of a false alarm) closer to 0.27% of the normal case. Even in the case where the process distribution is exponential with known mean, not only the control limits and Type I risk, but also the Type II risk of the SC charts are closer to those of the exact and R charts than those of the WV and Shewhart charts. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 555–573, 2003  相似文献   
243.
针对压控振荡器调频非线性误差的准确估计与校正问题,提出一种以一维距离像对比度最优为准则的自适应估计与校正方法。本方法建立引入温度变量的压控振荡器频率特性模型,并据此估计出某一温度值对应的调频非线性误差,在对中频回波进行误差补偿和一维脉压后,以一维距离像的对比度最优作为迭代收敛准则,实现调频非线性误差的最优估计与校正。仿真和实测数据结果表明,该方法充分考虑了温度因素对压控振荡器输出频率的影响,能够在不增加硬件复杂度的前提下,通过算法实现对调频非线性误差的估计、跟踪与补偿。与传统基于硬件电路进行估计或校正的方法相比,新方法无需由硬件组成闭环估计通道,且具有实时性强、运算量小、补偿精度高的优点,对于克服实际工程应用中压控振荡器器件的参数漂移问题具有重要指导意义。  相似文献   
244.
针对目前国内二维弹道修正处于起步阶段和一维弹道修正处于研制阶段,提出了一种基于距离及精度二次修正执行机构的驱动控制器,该驱动控制器模块是一种新型的修正组件控制模块,详细介绍了修正组件控制器的工作原理、修正原理和硬件电路设计。硬件电路设计主要包括升压电路、四路起爆电路和异或门电路。每路起爆电路可以独立控制一个阻尼片。该控制器可以完成多种模式的修正,不仅可以完成弹道修正弹的一维一次和一维二次距离修正,还可以完成弹道修正弹的二维修正。  相似文献   
245.
针对装备维修对实践经验的依赖以及经验的隐性化特点,重点对故障案例的表示及案例库组织进行研究,奠定案例检索的基础,优化基于案例推理的装甲装备故障排除方法。  相似文献   
246.
针对弹道导弹的目标特性和作战特点,对主要态势指标进行了提取,构建了基于BP神经网络的态势等级模型,并按照区间对预警等级进行划分。为提高模型的准确性和适应性,通过样本数据对BP网络进行了训练,并进行了仿真得到了态势等级。仿真结果表明:利用BP神经网络对态势等级进行研究是可行的。  相似文献   
247.
Ballistic missile defense (BMD) politics present an interesting evolution in how the USA, especially Congress, has come to think about BMD both as operational reality and as a symbolic policy. The argument here is that BMD's operational reality is increasingly overshadowed by its symbolic aspects. Such a status arose from rapidly changing international and domestic politics. The end result is a situation in which BMD policy in a sense floats above the question of its actual combat effectiveness. Its primary mission in part is sustaining US capacity to remain a global power and support its allies.  相似文献   
248.
This study revisits the long run and dynamic causal linkages between defense spending and economic growth in 15 selected European countries for the period 1988–2010 by utilizing recent developments in non-stationary panel data analysis. To this end, the series properties of per capita defense spending, per capita real capita stocks, and per capita real GDP are investigated by the panel unit root tests with and without breaks that support evidence on unit root. The panel cointegration tests with and without breaks are also subsequently employed to investigate whether there exists a long-run equilibrium relationship between these three variables. Finally, our causality analysis from panel vector error-correction model suggests that there is a feedback relation between real capital stock and real GDP in both short and long run, a one-way Granger causality running from real GDP to defense spending in both short and long run, and defense spending only Granger causes real capital stock in the long run.  相似文献   
249.
North Korea has been one of the world's most active suppliers of ballistic missile systems since the mid-1980s, but the nature of its missile export business has changed significantly during this period. Unclassified, publicly available data show that the great majority of known deliveries of complete missile systems from North Korea occurred before 1994. The subsequent fall-off took place a decade too early to be explained by the Proliferation Security Initiative of 2003. It can be explained by a combination of factors that have reduced demand. First, after selling production equipment for ballistic missiles to many states, especially in the Middle East, North Korea by the late 1990s had become primarily a supplier of missile parts and materials, not complete systems. Second, after Operation Desert Storm, some missile-buying states shifted their attention away from ballistic missiles in favor of manned aircraft, cruise missiles, and missile defense systems supplied by Western powers. Third, some states experienced pressure from the United States to curtail their dealings with North Korea. During the last decade, having shed most of its previous customer base, North Korea has entered a phase of collaborative missile development with a smaller number of state partners, particularly Iran and Syria. Its known sales of complete missile systems are relatively small and infrequent. North Korea's time as missile supplier to the Middle East at large has ended, but there is a risk that regional states will turn to North Korea as a supplier of nuclear technology in the future.  相似文献   
250.
ABSTRACT

Since 2002, NATO's territorial missile defense has evoked continuous debates between NATO states and the Russian Federation. Thirteen years have passed without reaching a common denominator. This article provides a comprehensive overview of the historical background of the debate and the technical details of the missile defense system, highlighting its shortcomings and the state of its deployment process. It also contrasts the military-technical and political arguments of both sides, before addressing the applicable norms of international law to highlight violations and the effect of this noncompliance on existing arms control measures.  相似文献   
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