探地雷达的地下目标定位方法

目标定位是雷达需要完成的主要功能之一,提出了机载探测时的地下目标定位方法-多点测量方法.在建立电磁信号从机载雷达到地下目标传播路径模型的基础上,该方法利用合成孔径技术中多点测量的特点,利用机载探地雷达在不同位置的回波时间,建立并求解包含目标信息的方程组,实现机载条件下探地雷达对地下目标的定位.同时得到了地层媒质的相对介电常数,为地层研究提供了有力条件.     

Military support and transnational terrorism

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.     

基于三级数据关联的红外点目标跟踪方法

介绍了目前红外系统的目标跟踪方法；在目标跟踪时的数据关联阶段，提出了三级门限数据关联算法，根据门限级别所划分的疑似目标点位置，算法采用不同的数据关联策略。该算法能减少轨迹分叉时的计算量，能有效地检测出速度〈1像素／帧的运动点目标。实验结果证明了该算法的有效性。     

地面微型网域武器攻击方案

提出了地面微型网域武器的三种攻击方案,并分析了三种攻击方案的优缺点,对地面微型网域武器的三种攻击方案进行了MATLAB仿真分析。在综合考虑各个因素后,得出了一种最佳攻击方案。     

Military deployment and international terrorism: do location and mission type matter?

Extant literature documents a relationship between military deployment and the risk of an international terrorist attack against citizens of the deploying country. It appears that deployment significantly increases the possibility of terrorist actions in the home country. In particular, if country A decides to send troops to nation B, then citizens of the former country are more likely to fall victim of an attack carried out by a terrorist organisation originating from the latter country. Contributing to this line of literature, we further refine this relationship by distinguishing between regions where the troops are sent as well as by introducing differences between types of deployment. Our results indicate that missions to Asia and the Middle East are more dangerous than missions to other regions as reflected by the terrorist threat in the home country. Robustness tests do however show that the significance of the location variable Asia is predominantly attributed to the mission to Afghanistan. As for types of deployment, only ad hoc missions seem to increase the risk of an attack, whereas no significant results are found for other missions such as operations under UN and NATO flag. Leaving out the missions to Iraq and Afghanistan however also increases the danger resulting from missions by fixed coalitions. Our results find however no evidence that ‘wearing a blue helmet’ increases the probability of a terrorist attack at home.     

论中国战略文化的近代流变

中华“天下观”把和谐的天下秩序作为基本的价值追求,并由此形成了求和平、谋统一、重防御的中国战略文化传统。近代以来,在西方“强权即是公理”的战略文化冲击下,为了实现救亡图存的历史使命,中国战略文化实现了文化革新,但其基本价值观念没有变,至今仍然影响着中国的对外战略选择。     

军用软件的测试与实践方法

首先分析了民用软件存在的问题,然后结合军用软件的特点,对影响军用软件可靠性的因素进行分析,最后提出提高军用软件质量的几种测试与实践方法.     

基于组合媒质通道模型的地下目标成像

由于电磁波在穿越不同介质时会出现折射现象,因此在地下目标成像过程中,电磁波信号穿越从雷达到地下目标的组合通道的路径不是直线而是折线,此时利用常规的自由空间中的合成孔径成像方法已经不能对目标进行成像。基于电磁波的传播规律和地层有耗媒质的特性,提出了电磁波传输的组合通道模型,并将其应用到地下目标成像中。通过仿真比较可以看出,使用组合通道模型对地下目标成像效果有明显的改善,组合通道模型适用于对分层土壤中的地下目标成像。     

箱式屏蔽效能测试方法及影响因素分析

为测试强电磁场作用下材料的屏蔽效能,基于屏蔽材料的屏蔽原理,提出一种在GTEM室内置屏蔽箱测试材料屏蔽效能的新方法,构建实验平台,仿真分析屏蔽箱窗口尺寸及测试探头位置对测试结果的影响．实验结果表明：测试窗口大小和测试位置对测试材料的屏蔽效能有影响．其主要影响因素是屏蔽效能的测试频率下限,并确定了0．6m×0．6m窗口的测试频率下限为55MHz,0．3m×0．3m测试窗口的测试频率下限为250MHz．     

Storage life prediction under pre-strained thermally-accelerated aging of HTPB coating using the change of crosslinking density

In order to predict the storage life of a certain type of HTPB (hydroyl-terminated polybutadiene) coating at 25 C and analyze the influence of pre-strain on the storage life, the accelerated aging tests of HTPB coating at 40 C, 50 C, 60 C, 70 C with the pre-strain of 0%, 3%, 6%, 9%, respectively were carried out. The variation regularity of the change of crosslinking density was analyzed and the aging model of HTPB coating under pre-strained thermally-accelerated aging was proposed. The storage life of HTPB coating at 25 C was estimated by using the Berthelot equation as the end point of the aging life with a 30% decrease in maximum elongation. The results showed that the change of crosslinking density of HTPB coating increased with the increase of aging temperature and aging time, and decreased with the in-crease of pre-strain. Under 0% pre-strain, the relationship between the change of crosslinking density of HTPB coating and the aging time can be described by the logarithmic model with the confidence probability greater than 99%.The stress relaxation phenomenon existed under 3%, 6% and 9% pre-strained aging. The aging model considering chemical aging and pre-strain was established with the confidence probability greater than 90%. The storage life of HTPB coating was 15.2935 years at 25 C under 0% pre-strain, which was reduced by 13.9007%, 75.6949% and 89.7859% under 3%, 6% and 9% pre-strain, respectively. The existence of pre-strain has a serious impact on the storage life of HTPB coating, therefore, the pre-strain should be avoided as much as possible during the actual storage.