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1.
Although the Taliban insurgency was internally divided and unable to coordinate its activities in 2014–2015, the Afghan security forces were not able to contain it and steadily lost ground throughout 2015. Until 2015, there had been little effort to develop an indigenous Afghan counterinsurgency strategy, but a sense of urgency emerged after a string of Taliban victories. At the beginning of 2016, it was still not clear if and when the National Unity Government would be able to produce a counterinsurgency strategy and, in any case, the need for a coherent counterinsurgency approach became questionable as the Taliban appeared to be transitioning towards conventional warfare.  相似文献   
2.
为了找到传感器稳定性最好时的脉冲周期,对传感器检测系统进行优化,实验研究了传感器检测饮用水中大肠杆菌时,脉冲周期对传感器稳定性的影响。传感器的构成属于三电极系统,采用常规脉冲伏安法进行检测。结果显示:脉冲周期为20,40,80 ms时传感器稳定性较好,基本不会影响检测结果;脉冲周期为100 ms时稳定性很差,对检测结果有较大影响。实验表明,选择合适的脉冲周期,加以硬件和软件补偿,可以使传感器获得较好的稳定性。  相似文献   
3.
基于ABAQUS有限元软件,采用主从接触算法模拟桩-土相互作用、修正剑桥模型作为土体本构模型,通过在桩顶施加竖向位移荷载以及合适的网格划分技术建立了较为符合压入管桩压桩实际的有限元模型。利用得到的有限元模型模拟了压入管桩压桩产生的挤土位移场,对不同泊松比时压入管桩单桩挤土位移场进行了对比分析。结果表明:不同泊松比时竖向和水平挤土位移场沿深度方向和径向的分布规律趋于一致;土体泊松比的变化会对压入管桩压桩产生的竖向和水平挤土位移场产生较大影响;泊松比越大,压桩产生的竖向和水平挤土位移越大。  相似文献   
4.
Afghanistan's fifth effort to form a central army started in 2002, following the fall of the Taleban regime. Mainly run by the US armed forces, the formation of the so-called ‘Afghan National Army’ run into several difficulties, ranging from initially slow recruitment, low educational level of troops and officers, high attrition rates. As the new army began to take shape, it lacked many of the characteristics which had been associated by the promoters with a ‘national’ army. It also showed a low level of commitment and a lax discipline. As of 2006, it looked more like an auxiliary force at the service of the US army and its allies than like a ‘national’ army.  相似文献   
5.
Why do countries have air forces? Organizational alternatives, such as maintaining separate air arms for the army and navy, have become quite rare. The conventional narrative advanced by advocates of independent air forces stress that the primacy of airpower in modern warfare mandates centralized control of most military aviation. In this view, political–military uncertainty has driven mimetic isomorphism – pressure on national governments to organize as others organize so as to fight or deter war just as effectively. However, working from a set of 56 countries that were politically independent within a few years of the establishment of the first ever independent air force (the Royal Air Force) in 1918, and continuing through nearly the present, there is no clear pattern of external military pressure prompting this particular reorganization. Rather, from anecdotal evidence, the cause has more likely been normative isomorphism – a professional craving to look as others look to foster political or personal legitimacy. For whatever reason, though, choices of structures tend to lead to specific choices of policies. Thus, the result suggests that defense ministries looking for more effective or less costly organizational schemas may reasonably consider alternatives to the tripartite army–navy–air force structure.  相似文献   
6.
科学社会主义理论是一个开放的体系,具有与时俱进的理论品质。中国改革开放的伟大实践有力推动了科学社会主义理论的发展,社会主义事业将不断发展,科学社会主义理论也将得到不断发展。  相似文献   
7.
In this article, we study how to derive bounds for the reliability and the expected lifetime of a coherent system with heterogeneous ordered components. These bounds can be used to compare the performance of the systems obtained by permuting the components at a given system structure, that is, to study where we should place the different components at a system structure to get the most reliable system. Moreover, a similar procedure is applied to get bounds for mixtures and for the generalized proportional hazard rate model when the baseline populations are ordered. © 2017 Wiley Periodicals, Inc. Naval Research Logistics 64: 108–116, 2017  相似文献   
8.
This article explores how the protection of civilians is being militarized by African policymakers and diplomats. I draw on practice approaches to analyze what social groups are doing when they claim to “protect civilians.” I show how innovative protection mechanisms can be seen as a function of officials and diplomats coping with the changing circumstances of increasingly militarized politics in Africa. Specifically, accountability mechanisms for unintended and intended civilian harm by African security operations have originated in connection with this development. I argue that these are results of anchoring practices, which means that everyday informal interactions in one context become linked to another context. I argue that these emerging accountability mechanisms represent a new combination of practices, with the potential of changing the routine activities and mutual learning between policymakers and diplomats.  相似文献   
9.
Within the framework of classical theory, the joint US Army-Marine field manual Counterinsurgency (FM 3-24) described an ambitious set of skills required for success against guerrillas. But if counterinsurgency, as FM 3-24 describes it, is ‘the graduate level of warfare’, then these two military services have been for years systematically failing to train their talent in the appropriate fields. In today's small wars, NCOs serve as modern-day Mounties, and consequently require at least a modest undergraduate education in armed good governance.  相似文献   
10.
花园洋房是具有悠久历史的住宅产品,现代花园洋房日益受到喜爱。为适应现代居住舒适、经济、安全的要求,寻求更加适合现代社会居住的花园洋房设计方法,基于花园洋房发展趋势与设计思想分析,结合具体设计方案,着重探讨套型叠加、空间过渡、下沉空间和洋房电梯等设计方法,从而为现代花园洋房设计方法的优化提供借鉴。  相似文献   
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