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171.
ABSTRACT

The Chinese military has embarked on a series of organizational and doctrinal reforms intended to better enable it to fight modern war. Prominent among these reforms is the growing emphasis on space to enable long-range precisions strikes and on counterspace to deny space capabilities to an adversary. The People’s Liberation Army (PLA) has officially designated space as a new domain and established an organization to command space forces. With this increased focus on space, the PLA may begin to develop a doctrine to govern the use of space in military operations. The higher priority given to space, especially space control, by the PLA coincides with similar actions by the US military, increasing the possibility of warfare in space and the risks of escalation.  相似文献   
172.
Once dismissed by many outside observers, the Chinese People’s Liberation Army Air Force (PLAAF) has undergone an impressive transformation over the past two decades, emerging as one of the world’s premier air forces. As it continues to modernize, it is focused on becoming a ‘strategic air force.’ PLAAF strategists suggest this means it should play a decisive role in protecting Chinese national interests, field modern capabilities commensurate with China’s standing as a major power, and enjoy the institutional status befitting its role as a ‘strategic service,’ an important consideration given the historical dominance of the ground force in China’s military.  相似文献   
173.
稀薄流高超声速飞行器气动加热耦合计算   总被引:1,自引:1,他引:0       下载免费PDF全文
针对稀薄流域高超声速飞行器的气动加热问题,开展耦合数值计算研究。通过引入牛顿冷却定律,将直接模拟蒙特卡洛数值模拟方法与结构传热计算方法相结合,设计一种可对全机外形进行气动热和结构传热计算的高效松耦合方法,实现飞行器防热层结构材料温度分布特性的数值模拟。在以钝锥外形为例对直接模拟蒙特卡洛数值模拟程序进行验证的基础上,采用该方法对X37B轨道飞行器外形长时加热与结构传热过程进行数值模拟,给出结构温度及热流密度随飞行时间的变化规律。研究结果表明,设计的耦合计算方法能够模拟稀薄流域高超声速飞行器的气动加热及结构传热耦合过程,可为该类飞行器的气动热分析及热防护设计提供技术支持。  相似文献   
174.
This paper is a survey of Angola’s defence sector and policy from 1992, the year the civil war ended, to 2012. Angola achieved its independence upon the Popular Movement for the Liberation of Angola (MPLA) defeating National Union for the Total Independence of Angola. Since then, fuelled by its rich natural resources, the country has grown steadily. The MPLA military forces were a central factor behind independence and maintain their central role to this day. Moreover, Angola’s support for African peace with monitoring military missions is a clear indication that the country aims to intervene in African security and military issues, with its military capabilities funded by oil revenues.  相似文献   
175.
Recent literature on whether military spending affects economic growth argues that the relationship may be a conditional one. We add to this literature by considering the role that ‘good institutions’ play in the effect of military spending on growth. Using data from a sample of over 100 countries from 1988 to 2010, our analysis suggests that the effect of military spending on growth is generally negative or zero at best, and this effect is mitigated in the presence of good economic and political institutions.  相似文献   
176.
The public expects European governments and the European Union (EU) to deal with the security challenges in and around Europe. So does the US, whose strategic focus has pivoted to the Pacific. Washington, DC has made it clear that it will not, and cannot, solve all of Europe’s problems. The call for ‘strategic autonomy’ in the new EU Global Strategy of June 2016 does not come a moment too soon. But should the aim be EU strategic autonomy, without the UK, or can the aspiration still be European strategic autonomy, with the UK? Can nothing be achieved unless all are fully involved? Or are intermediate solutions possible? How EU Member States and the UK answer these questions will determine which degree of strategic autonomy the EU can achieve. With which degree of British involvement. And whether the UK itself will be left with any measure of strategic autonomy.  相似文献   
177.
美国海军的新型舰载垂直发射装置   总被引:3,自引:0,他引:3  
简要介绍了美国海军新型舰载垂直发射装置CCL,分析了其组成、性能、结构和所使用的电气设备,指出了它的优点.  相似文献   
178.
ABSTRACT

In combat, the ratio of shots fired per casualty inflicted can provide a measure of the combat effectiveness of a force. The shots per casualty ratio achieved by the 1st Australian Task Force in Vietnam is shown to change according to factors including marksmanship, tactics and combat type. While, over the course of the campaign, 1ATF fired an increasing number of shots to achieve a casualty, this is explained by improvements in the quality of Viet Cong and People’s Army small arms. Australian Task Force and US Army shots per casualty ratios are briefly compared..  相似文献   
179.
《防务技术》2020,16(3):514-519
This article presents the texture development of magnesium AZ31 alloy in the accumulative roll bonded (ARB) AZ31/AZ31 multilayer and AZ31/AA5086 laminate composite. The comparative study demonstrates that the texture evolution in AZ31 in a multilayer system is strongly influenced by the interfaces. A typical basal texture of AZ31 has been observed in AZ31/AZ31 multilayer with texture intensity increased with the rolling deformation. Presence of AZ31/AA5086 interface in the laminate composite leads to a tilted basal texture along the rolling direction (RD) in AZ31 alloy. The texture intensity of composite increased initially with rolling reduction and weakened at the higher rolling strain. Weakening of texture in AZ31 during the laminate processing at higher strain has been attributed to the development of wavy interfaces in AZ31/AA5086 laminate.  相似文献   
180.
Norway, Sweden and Finland have proclaimed a willingness to cooperate militarily in a future crisis or conflict despite their diverging alliance affiliation. This article assesses their ability to do so through various elements affecting their interoperability, with Arctic Challenge, a multinational military exercise, as an empirical basis. The analysis finds that the NATO/non-NATO-divide has a negative impact on the trilateral defence cooperation, especially on exchange of information and aspects related to command and control. At the same time, Finland and Sweden have become largely NATO-standardized through their active partnership with the Alliance. This has affected interoperability aspects, such as communication, culture, and the compatibility of technical solutions, in a positive manner. Through agreements with the Alliance, as well as domestic legal changes, the two NATO-partners have facilitated receiving military assistance from Norway and other NATO-members during a crisis. Other agreements between the Nordic countries, however, have been limited to peacetime.  相似文献   
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