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751.
Kristýna Pavlíčková 《Defense & Security Analysis》2020,36(3):335-351
ABSTRACT The recent rise in the defence budgets among the NATO members reawakens the free-riding dilemma. This article provides an analysis of the defence spending of two new member states, the Czech Republic and Lithuania. Based on the free-riding theory, we explain why some of the new NATO members decide to increase their defence budgets (Lithuania), and others do not (Czech Republic). In contrast to the majority of works which focus either on the US as the biggest spender or on the “old” members of the Alliance, we explain under what circumstances some of the small European states who became new NATO members started to increase their defence budgets even though they do not have to, and the literature suggests that free-riding is easier. In the process, we identify three crucial factors that in?uence the decision-making process in this regard: the level of threat perception, economic situation, and the US pressure. 相似文献
752.
俄罗斯按照建设航天力量的需求,积极研究现代空天防御教学技术设备。俄罗斯空天防御教学训练设备可帮助受训者利用所获得的知识与能力,在准备和完成实践任务时在不同系统设备间实现不同级别的综合协同,将实现结构和软件的模块化。俄航天兵使用空天防御教学训练设备的经验对军队空天防御专业人员训练具有重要的借鉴意义。本文分析了俄罗斯空天防御教学训练设备现状,研究了朱可夫空天防御军事学院一体化空天防御自动化控制系统教学试验模型的构成、原理、作用和应用,总结了俄罗斯空天防御教学训练设备在国家标准、教学法、工效学和组织方面存在的主要问题及解决办法,以期为军队空天防御教学训练设备发展提供参考。 相似文献
753.
为了研究空间站平均力矩平衡姿态的影响因素,建立了空间站的姿态运动模型,分析了气动力矩对空间站平均力矩平衡姿态的影响。建立了空间站的动力学与控制模型,采用典型的比例微分控制器,分别得出了两种条件下的24组平均力矩平衡姿态(Average Torque Equilibrium Attitude,ATEA),结果表明气动力矩对ATEA的影响显著。为了保持空间站ATEA,需要提供周期性的控制力矩。气动力矩引起的空间站角动量卸载和积累效应不能被忽视。 相似文献
754.
Lazar Zsolt 《Defense & Security Analysis》2018,34(2):161-175
The post-communist countries transition from the Warsaw Pact style of platforms and systems to Western-compatible capabilities has never been an easy task or a process without conflicts. This was no different for the Visegrád countries either, in which case the Hungarian Gripen procurement stands out. After much debate, Budapest decided to modernize its fighter fleet with the not battle tested Swedish-made Gripen fighter aircraft. This decision received several critiques due to the lack of transparency in the selection process and the initial lack of NATO-required systems. Subsequently, the fleet has had to operate in a financially demanding environment. Moreover, the air force has lost two aircrafts in accidents. Now that the jets are in the middle of their envisaged life cycle, it is more than appropriate to answer the question if the Gripens can utilize their full combat potential or will they fail the test of time? 相似文献
755.
Bence Nemeth 《Defense & Security Analysis》2018,34(1):16-34
As a result of the migration crisis of 2015–2016, the management of mass migration and border control became militarised in Central Europe, and this process has also reshaped the dynamics of multinational defence cooperation in the region. Accordingly, while the so-called Central European Defence Cooperation (CEDC) was created by Austria, Croatia, the Czech Republic, Hungary, Slovakia and Slovenia in 2010 to support NATO and EU capability development projects via defence cooperation, after the migration crisis it became the major Central European forum for military cooperation against irregular mass migration. Although many defence officials in the region are not necessarily enthusiastic about this development, the Central European political environment and also practical defence considerations pushed the defence ministries of CEDC countries towards deeper cooperation on border control, as well as better coordination with ministries of interior affairs on the national and the regional levels. 相似文献
756.
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758.
通过模拟实验,研究了磁隐身坦克的核心元件——同轴密绕消磁线圈的使用性能。实验室对其消磁效应的数据分析表明:同轴密绕消磁线圈能够消除坦克周围因被地磁场磁化而产生的磁场标志,其中近轴区域的消磁效果更为明显;如果在消磁线圈中通入反向电流,消磁物体的磁场反而会增强,呈缓慢磁化的趋势,这与电磁场理论相符。本实验设计的消磁线圈属于一种新功能的电磁装甲,能提高坦克在电磁战中的生存能力。 相似文献
759.
在分析伞降高度选择影响因素的基础上,研究了敌反空降防空火力对伞降高度选择的影响,给出了各类防空火力对不同高度实施空降时运输机和伞兵毁伤数的计算公式;基于伞降高度选择原则建立了伞降高度选择模型.通过实例证明了模型的合理性,可为空降作战决策提供参考依据. 相似文献
760.
介绍了安全轮胎的定义和主要技术类型,根据车辆防护性对安全轮胎的要求,对考核轮胎防护性的试验评价方法进行了研究,提出了相应的道路行驶试验方法。为了获得轮胎防护性的量化特征,建立了轮胎防护性评价指数模型,为评价轮胎防护性能提供了一种分析方法。 相似文献