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991.
The build-up of Japan's military apparatus in the 1990s and 2000s has been often regarded by security analysts as indicative of a departure from the country's Cold War strategic posture. Japan appears to be engaged in a process of militarisation that is eroding the foundations of its ‘exclusively defence-oriented’ policy. In the case of the archipelago's naval strategy, such assessments overlook the longstanding significance of a core feature of its defence policy, namely the surveillance of maritime crossroads delivering the wealth of the country. The paper reassesses the evolution of the Japanese strategy since the Cold War by examining the development of the Japanese Maritime Self-Defence Force's submarine force, one of the key components of the defensive shield for these crossroads. The paper argues that with the changes in the security environment of the 1990s, Japan already fielded a mature force with state-of-the-art submarines, and that the rise of a new naval competitor aiming at controlling key strategic points along Japan's sea lanes reconfirmed the critical importance of submarine operations to Japanese national security.  相似文献   
992.
The track record of the US military in unconventional wars has not been good and there were fears that Operation ‘Enduring Freedom’ might suffer the same fate as previous campaigns. This contribution explores why the Taliban were defeated so easily by the US in 2001. It challenges the view that America's victory was due solely to changes in its modus operandi or that the outcome heralds a change in the fortunes of the US when fighting unconventional war. It also questions the idea that America's victory was a consequence of Taliban incompetence. Instead, it explains the defeat of the Taliban in terms of the prevailing political conditions within Afghanistan, which made them vulnerable to attack. The essay concludes that current political circumstances could, in the long run, permit the resurrection of the Taliban and undermine the US-led coalition's victory.  相似文献   
993.
994.
ABSTRACT

This article analyses the Zimbabwe People’s Revolutionary Army operations in Mashonaland West province with particular reference to Makonde District during the country’s war of liberation. Despite the growing literature on ZAPU and ZPRA in Zimbabwe’s war of liberation there is little that has been written concerning the operations of ZPRA guerrillas in Mashonaland provinces. Guided by evidence drawn from secondary and primary sources the article further asserts that ZPRA adopted a four pronged strategy in Makonde District. This strategy in part was hinged on the politicization of the population on the one hand and annihilation of the enemy forces, attrition and manoeuvre warfare on the other. Again, the article argues that ZPRA guerrillas attempted to capture Salisbury (Harare) in order to conquer the Rhodesian Security Forces’ centre of gravity. It was hoped that the capture of the capital city would Makoni District was of strategic significance to the conduct of ZPRA operations and arguably hastened Ian Smith’s decision to attend the Lancaster House Conference negotiations that led to the independence of Zimbabwe in 1980.  相似文献   
995.
Personal cognitive processes inform how individuals understand their environment. Cultural variation, fundamental attribution error, causal attribution, and durability bias create obstacles to Western understanding of irregular war and have created a significant institutional bias in how the US military perceives its enemies- a perception only somewhat softened after a decade of irregular war. United Special Operations Command (USSOCOM) is in a better position to overcome these problems through persistent engagement. In the event of major conflict, environmentally sensitized military planners will be better able to achieve military and policy objectives.  相似文献   
996.
卫星导航系统评估星载钟稳定度通常需要大型地面监测网的观测数据和复杂的钟差确定算法,不能基于单站观测数据实现。论文在分析利用单站观测数据评估星载钟短稳方法的基础上,提出了一种相对容易实现的联合卫星双向载波测距值与GNSS单向载波观测值的星载钟短稳评估方法。该方法通过卫星双向载波测距确定星地几何距离,基于消除星地几何距离的GNSS接收机载波相位观测值估算卫星相对钟差,进而实现其短稳评估。利用北斗系统观测数据进行了有效性验证,并与复杂钟差确定算法以及利用平滑广播星历的方法(SBE法)进行了对比,本文方法与复杂钟差确定算法计算的结果相符,在1000s平滑间隔内与SBE法结果一致,相对误差小于10%,1000s以上好于SBE法。  相似文献   
997.
伴随着互联网规模的不断扩展,信息过载问题越来越突出。信息推荐系统被视为解决信息过载问题的最有效方法。然而目前的方法大多数仅考虑用户独立的反馈,而忽略用户的社会属性对推荐的重要作用,这对信息推荐系统的性能会造成巨大的影响。为此,本文提出了基于朋友关系预测的信息推荐算法,将用户的社会关系预测引入信息推荐过程中,分别基于用户的拓扑信息及历史交互信息建立用户社会关系的存在性判定及关系类型判定,并利用线性回归分析方法和逻辑回归分析方法实现了基本特征的融合。最后,通过在Epinions和Slashdot真实数据集上的实验证明,本方法能够有效提高用户社会关系预测的准确性。  相似文献   
998.
电池管理系统(battery management system,BMS)是混合动力汽车(parallel hybrid electric vehicle,PHEV)能量管理系统中的核心组成部分,而其中电池电荷状态(state of charge,soc)则是PHEV控制策略中的重要参数.针对PHEV动力电池组SOC系统高度非线性和复杂性的特点,提出了一种基于改进的BP神经网络的HEV动力电池组的实时SOC估计,并对网络的收敛性进行了证明.利用大量PHEV动力电池组在行驶过程中充放电的数据样本,对神经网络进行网络训练并且进行仿真.结果表明,与传统离线SOC估计方法相比,能够有效地减小误差,提高电池SOC的精度.  相似文献   
999.
主要以信息化条件下如何提升海军舰艇编队防空导弹作战能力为背景,重点描述协同指挥和协同制导作战的概念内涵、国内外研究现状、作战模式、主要实现的功能,给出不同指挥层次下各指挥节点的体系结构和功能定位,进而从信息场和功能界面等方面说明协同指挥和协同制导2个功能层次的区别.  相似文献   
1000.
为了提高无人机模拟训练的逼真度和沉浸感.研究了无人机飞行操作训练的关键技术,以半实装的形式构建了模拟飞行训练系统的体系结构.通过对飞行操作训练关键技术的研究和飞行操作模拟训练系统的设计,可以对基层部队的无人机地面操控手高逼真模拟训练提供理论基础和系统支持.  相似文献   
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