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11.
一种变结构导引律及其在垂直命中制导中的应用   总被引:5,自引:0,他引:5  
基于变结构控制理论 ,提出了一种垂直命中目标的导引律。该导引律在引入理想的视线角基础上 ,所设计的切换函数不仅保证脱靶量为零 ,而且能同时达到垂直命中目标的目的。数字仿真表明 ,该导引律与最优垂直命中导引律相比 ,不仅适用范围广 ,而且具有良好的鲁棒性能。  相似文献   
12.
Abstract

In Operation Iraqi Freedom, which ended in August 2010, nearly 3500 hostile deaths occurred among US military personnel and 32,000 more were wounded in action (WIA). More than 1800 hostile deaths occurred during Operation Enduring Freedom (in and around Afghanistan) through 2014 and about 20,000 were WIA. A larger proportion of wounded personnel survived in Iraq and Afghanistan than during the Vietnam War, but the increased survival rates were not as high as some studies have asserted. The survival rates were 90.2% in Iraq and 91.6% in Afghanistan, compared with 86.5% in Vietnam. The casualty rates varied between the conflicts in Iraq and Afghanistan and before, during, and after the respective surges. Amputation rates are difficult to measure consistently, but I estimate that 2.6% of all WIA and 9.0% of medically evacuated WIA from the Iraq and Afghanistan theaters combined resulted in the major loss of a limb. Elevated non-hostile death rates (including deaths due to accidents, illnesses, homicides, or suicides) resulted in about 220 more deaths in Iraq and about 200 more deaths in Afghanistan than would have been expected in peacetime among populations of the size deployed to those two conflicts.  相似文献   
13.
QI Zhiqiang  LV Rui 《国防科技》2018,39(1):081-085
近年来,随着智能移动终端和互联网技术的结合,上网变得十分便利。网民数量激增的同时,网络谣言层出不穷,给社会安全与稳定造成不良影响。文章从心理学角度深入分析助推网络谣言的原因,并基于心理规律提出网络谣言的管控措施。  相似文献   
14.
The Sri Lankan Civil War (1983–2009) is regarded as a violent reflection of deepening divides along political and ethnic lines. During this civil war the Sri Lankan Government and its security forces have been implicated in unlawful killings carried out in a pervasive manner against civilians, whilst at the same time specifically targeting ethnic Tamils, humanitarian workers and journalists. The human rights of all citizens suffered as a result and ultimately led to the weakening of the rule of law. With the end of the civil war, the Sri Lankan Government has made little progress in providing accountability for wartime abuses. Its absence of and reluctance to ensure justice is seen as a logical culmination of decades of impunity. The importance of acknowledging historical behaviour and taking accountability for past violations will be discussed. In an analysis for paving the way to a new democracy in Sri Lanka, the main outcomes of this article are calls for accountability arising out of the government’s actions during the war; an investigation into the present state of human rights, the rule of law and finally; an examination into the political solution going forward to ensure a process of reconciliation and peaceful co-existence.  相似文献   
15.
简化电磁发射装置中的导轨和电枢为线电流下的直导体,建立发射装置的物理模型。利用毕奥-萨伐尔定律和感应电动势原理,推导出磁探针线圈中心放置点的磁感强度。假设线圈范围内的磁场为均匀磁场,计算得到磁探针线圈产生的电动势。以此设计测量所用的磁探针,并和测试数据对比验证模型的正确性。在多次试验中发现,发射过程中装置振动导致磁探针距离变化和角度偏转问题。测量并分析三组单次发射中的故障测试状态。仿真和实验数据表明:小范围距离变化没有使磁探针的测试性能失效,但角度偏移对下一步的速度拟合带来误差干扰,且随着角度增大拟合速度逐步减小。  相似文献   
16.
A comprehensive paradigm of future wars can be defined, and is called in this article “Extended conflicts.” These can be characterized by strategic attrition, to which all national resources and all possible international legitimacy are mobilized, in order to achieve a resolution by transformation of the opponent. The use of military force in this kind of conflict is limited. The understanding that we are facing an era of extended conflicts will improve the way it is utilized.  相似文献   
17.
考虑制导炮弹由身管武器发射,其飞行控制能力和导引信息量有限,基于预测落点位置偏差量来修正速度方向并在控制时间内连续分配导引指令的思想,提出了一种新的三维末制导方法。根据非线性弹道方程组的级数解预测弹丸落点位置,得到落点与目标的偏差,并提出了两种通过此偏差解算当前速度方向修正量的方法。取剩余飞行时间为修正时间,通过将速度方向修正量分配到整个剩余导引段建立了加速度修正公式,以减小导引指令饱和的可能性。通过连续地预测落点和分配加速度指令来实时地导引飞行。仿真结果表明:该导引方法简单可行,精度高,对控制能力要求较低,且具备较好的制导效果和毁伤效果,为该体制制导炮弹的应用提供参考依据。  相似文献   
18.
This paper attempts to investigate the long-run and the causal relationship between military expenditure and income distribution in South Korea for the period 1965–2011. Applying the bounds test approach to cointegration, we found a long-run relationship between military expenditure and the Gini coefficient with military expenditure having a positive and a statistically significant impact on income inequality. A 1% rise in military expenditure increased the Gini coefficient by 0.38%. Application of the lag-augmented causality test also reveals a unidirectional causality running from military expenditure to income inequality. The evidence seems to suggest that devoting more resources to the military sector may further worsen income inequality in South Korea.  相似文献   
19.
Analysing the relationship between the provision of military support and the probability of becoming the target of a terrorist attack, this paper contributes to the literature on the causes of transnational terrorism. We find that deployment of military troops of country X in country Y increases the probability of a terrorist attack on citizens of country X by a terrorist group located in country Y. Exporting weapons to country Y seems to increase the probability of being attacked by the terrorists of this country Y as well. Deploying materials, however, does not seem to significantly influence the probability of attack. Including lagged values for our military support variables ensures that the causality direction is from military support to terrorist attacks. Moreover, these results indicate that while the effect of military deployment on the probability of attack lasts for more than 1 year, the effect is rather short-lived.  相似文献   
20.
This paper develops a Dynamic Stochastic General Equilibrium model where national security is an argument in the agent’s utility function and the government chooses optimally the level of military spending to maximize social welfare. National defense depends on military expenditure and on the strategic environment reflecting a potential hostile external threat. We use aggregate data on consumption, investment, and military spending for the US economy to estimate the parameters of the model. Estimation results suggest that consumption and national defense are complements and that military spending variability is mainly explained by external threat shocks although it also depends on the macroeconomic conditions. We compute impulse response functions of the main macroeconomic variables to several shocks: a total factor productivity shock, a defense technology shock, and a strategic environment shock. Surprisingly, we find that the optimal response to an increase in the external threat (a worsening in the strategic environment) will rise output by reducing consumption and increasing investment.  相似文献   
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