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It is intrinsic to the nature of military competition that the unit acquisition costs of defence systems rise generation by generation. Traditional “bottom‐up” methods of cost‐estimating cannot meet the increasing demands for extensive studies of many options before commencing design and, while “top‐down” estimating techniques are an improvement, in particular by reducing the time required for preparing estimates, they also are inadequate to meet current requirements. A new method has been devised, therefore, further developing “top‐down” methods using Bayesian techniques to make best use of the available information, whether certain or uncertain, and its accuracy established by example.  相似文献   
94.

This paper analyzes a set of observations by the Congressional Budget Office (CBO) on individual weapons systems regarding whether large amounts of excess capacity exist and whether short run average cost (SRAC) appears to be severely decreasing. It is shown that the amount of excess capacity and steepness of SRAC are essentially independent of output rate. It is then argued that this suggests that production is occurring in inefficiently large plants—i.e.—off the long run cost curve.  相似文献   
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Despite all the talk of ‘hearts and minds’ being the key to counterinsurgency, local public opinion is rarely studied and when it is, it often yields surprising conclusions. Through analyzing polling data from Vietnam, Iraq and Afghanistan, this article shows that public opinion is less malleable, more of an effect rather than a cause of tactical success, and a poor predictor of strategic victory. As a result, modern counterinsurgency doctrine’s focus on winning popular support may need to be rethought.  相似文献   
97.
The People's Republic of China (PRC), no longer content with its longstanding ‘minimalist’ nuclear posture and strategy, is enhancing the striking power and survivability of its theater and strategic missile forces and rethinking its nuclear doctrine in ways that may pose serious challenges for the United States. Although the modernization of Chinese nuclear and missile forces may ultimately result in greater strategic deterrence stability, this change will not come about immediately or automatically. Indeed, it is entirely possible that China's growing missile capabilities could decrease crisis stability under certain circumstances, especially in the event of a US–China conflict over Taiwan.  相似文献   
98.
In its colony of Angola, Portugal during its colonial wars (1961–1974) was able to exploit the economic dependence and divided population loyalties of its hostile neighbours the Congo and Zambia as well as the cleavages within the nationalist movements to prevent a crippling insurgency. The rulers of both countries were largely dependent on Angola for trade, and were eager to have the side effects of the robust Angolan economy with its 11% annual growth brush off on their own moribund ones. While relationships were never comfortable, the sponsors of revolution were forced to reign in their ‘freedom fighters’ in order to maintain the functioning of their export-dependent economies. Portuguese leadership also played a vital role, as it was able to bring together diverse elements of national power in a concerted policy for dealing with these enemies, whether they were insurgents or their sanctuary countries. This policy of leveraging national power and playing on the vulnerabilities of its opponents worked well during its war in Angola and still holds valuable lessons for countries that find themselves in similar circumstances.  相似文献   
99.
On 4 January 1961 in Baixa do Cassange, in the north of Angola, the blacks who worked in the cotton fields began a strike. The army with air support was called to quell the rebellion, and the article emphasizes the importance of air support tethered to the ground forces, particularly in a remote and vast area of operations in the tropical rainy season. In this case, the support originally came in the form a squadron of Lockheed PV-2 Harpoons from Luanda, some 300 kilometers away. These open-ocean reconnaissance aircraft and their crews were ill-suited for the task. When this became apparent, four small Auster D5/160s were relocated from Negage to Malange, among the ground forces. The Austers flew reconnaissance missions over the troubled zones, dropped provisions and messages to the advancing ground forces, and served as a backup communications link. When the strike ceased after three weeks, the Austers assumed a humanitarian role in support of the starving population. The conclusion is that air support to ground forces is indispensable, must be properly tailored to the job, and must operate as an integral part of the ground forces.  相似文献   
100.
ABSTRACT

This article discusses the shortcomings of the “de-radicalization doctrine” in sub-Saharan Africa. The issues raised are illustrated by the war against Boko Haram, which involves Nigeria, Niger, Chad and Cameroon. Relying on interviews with security officers, insurgents, civil servants, displaced people, humanitarian workers and Muslim and Christian clerics in Nigeria, Niger and Chad since 2005, the investigation shows that the four states focused on repression rather than demobilisation programs in prison or outdoors. The Boko Haram crisis is mainly a story of mismanagement. The article thus challenges the assumptions of the “de-radicalization doctrine” in Muslim Africa South of the Sahara. First, attempts to de-radicalize jihadi terrorists tend to focus too much on religious fanaticism and the exegesis of the Quran. Secondly, they are neither feasible nor efficient. Finally, they obscure priorities that are more important to counter extremism and demobilize insurgents.  相似文献   
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