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排序方式: 共有365条查询结果,搜索用时 171 毫秒
81.
Robbie J. Totten 《Defense & Security Analysis》2015,31(3):199-212
What are relationships between epidemics, national security, and US immigration policy? This question is important because it sheds light on transnational or nontraditional security areas, American immigration policy, and a pressing issue for US leaders who have recently faced epidemics such as the West Africa Ebola outbreak that began in 2013. This article answers it and lays ground in the area by reviewing epidemics in world history, using International Relations and Security Studies works to specify dangers of contagions for states, and identifying three general immigration measures that American leaders have utilized from the seventeenth century to the present day to protect against contagions, which are (1) policies restricting entrance of foreigners thought to carry specified diseases, (2) the isolation or quarantining of immigrants with contagious disease, and (3) delegating the President with authority to stop immigration in the event of an epidemic abroad. This study has implications for research and contemporary US immigration policy. 相似文献
82.
火箭基组合循环发动机引射模态飞行状态复杂,为了提高发动机的整体性能,研究了火箭出口面积对发动机引射模态的影响规律。通过数值模拟研究,引射流量在低飞行马赫数条件下,主要受引射性能影响,火箭出口面积越大,引射性能越好。然而,随着飞行马赫数的提升,引射空气的动能提升,隔离段内出现壅塞情况,引射流量主要受限于隔离段几何尺寸,与火箭出口面积无关。在亚声速工况下,火箭出口面积越小,发动机比冲越低,且出口无量纲面积为3.15时,火箭羽流膨胀撞壁,会引起性能骤减,需要予以避免;在超声速工况下,选择面积较小的火箭出口面积,燃烧室内压越高,发动机性能提升越明显。 相似文献
83.
84.
Robert Johnson 《Small Wars & Insurgencies》2014,25(3):647-668
This article addresses Western recruitment and management of personnel from non-Western countries in armed forces as part of a strategy of state stabilisation, examining its risks and benefits. ‘SFA’ (Security Forces Assistance) to indigenous forces has long been practised by the West and seems to have returned in recent years in a new form with the creation of armies in Iraq and Afghanistan. However, while providing cheap, proxy substitutes for the West and offering opportunities for state-building, the policy creates its own problems and can have significant, negative consequences. 相似文献
85.
86.
In most western countries, there is a strong incentive for defence department budget-holders to expend all of the funds they are authorized to spend in a fiscal year. In this paper, we question whether this emphasis makes sense. We develop a model of a defence department’s operating expenditure assuming a fixed level of funding for a year and uncertain costs. The results of the model suggest that the incentive for departmental managers to expend all authorized funds is inefficient. We explore the implications of the model for the Department of National Defence (DND) in Canada in light of the recent criticism of DND lapsed funding by the Auditor-General of Canada. 相似文献
87.
After the fall of the Berlin Wall, European governments adopted a hands‐off policy towards the defence industrial base, in an attempt to increase the sector’s efficiency and reactivity. In this context, one topical issue is how to motivate defence firms to apply for private rather than public finance. Since banks have no prior experience with European defence firms, a problem of asymmetric information may block this transition. The problem is analysed within the framework of a game between defence firms and banks. It is shown that the Bayesian Equilibrium might correspond to a situation where low‐risk firms prefer the state‐financed scheme; yet, in a perfect information set‐up, the same firms would apply for bank credit. In order to facilitate the transition to private finance, the government might decide to subsidize investors who agree on financing defence firms; the state aid should be made available during a transitory learning period. 相似文献
88.
This paper aims at forecasting the burden on the Greek economy resulting from the arms race against Turkey and at concentrating on the leading determinants of this burden. The military debt and the defence share of GDP are employed alternatively in order to approximate the measurement of the arms race pressure on Greece, and the method used is that of artificial neural networks. The use of a wide variety of explanatory variables in combination with the promising results derived, suggest that the impact on the Greek economy resulting from this arms race is determined, to a large, extent, by demographic factors which strongly favour the Turkish side. Prediction on both miltary debt and defence expenditure exhibited highly satisfactory accuracy, while the estimation of input significance, indicates that variables describing the Turkish side are often dominant over the corresponding Greek ones. 相似文献
89.
Whose preferences determine the tradeoff between security and civilian output in deciding upon budget allocations to defence? This paper considers the role that consumer preferences might play in influencing military spending. We propose normative criteria to judge the economic or political efficiency of defence provision at a given time, and test them using Australian survey‐based micro‐data. Our results suggest that the political system has not delivered a simple social‐choice translation of individual preferences into collective outcomes, nor has it delivered results consistent with simple majority‐voting median preferences. 相似文献
90.
This paper explores some of the key issues associated with the restructuring of the defence industry. A comparison is made between the US and the European Defence Industrial Bases in terms of the drivers for change and the paradigms within which change has taken place. Having shown that some very important differences exist, the paper then explores the approaches that have been adopted for industry consolidation and references them to the academic literature on mergers and acquisitions (M&As) and strategic alliances (SAs). Given that most of the key defence players recognise the need to be global players, the paper presents an argument that the European firms’ experience of operating with a wide range of forms of corporate alliance will serve them in good stead for operating on a global defence scale. US firms, in contrast, have focused largely on M&A activity. 相似文献