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131.
This article aims to review some of the key lessons learnt by the Royal Ulster Constabulary's (RUC) Special Branch in the 37 years of the troubles in Northern Ireland. Above all counter-terrorism is an intelligence led operation and Special Branch are the key agency for this in all UK police forces, who have now benefited enormously from the expertise that the RUC's Special Branch built up over the years and have passed on to their colleagues throughout the UK. Intelligence is more often than not a human role and relies on human agencies, which was the case in Northern Ireland. The bulk of intelligence gathering was carried out at quite low levels although the sifting and analysing of it became a more specialist skill. Electronic intelligence and computerised systems were often quite low down in the order of priorities and uses, which tends to confound popular impressions. Agents, informers and good old fashioned ‘coppers’ who knew their patch were much more important both in terms of gathering information and in terms of undermining the terrorists morale from within and it was these factors that fundamentally defeated the IRA in Northern Ireland.  相似文献   
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Available sources value transfers of weapons irrespective of whether they are paid for and how. Data from the U.S. indicates that the shares of arms given for free or on credit are high. If other arms exporters, all military aid and all credits used for military purposes are considered, which is done here on the basis of rough estimates and an opportunity cost model, the true cash costs of weapons in the year of the actual transfer are small. On the other hand, the financial burden of earlier arms imports via debt service has grown over time. It most probably exceeded the true cash cost of imports of arms in the late 1980s. Large differences between arms transfer data and the actual true costs of arms transfers means that analysis of the economic effects of arms imports without considering these financial aspects makes little sense.  相似文献   
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This paper experimentally tests a number of hypotheses that follow from models of international competition that are based on Tullock style rent‐seeking models. Specifically, we designed and performed experiments to see how variations in the degree of publicness in the prize as well as changes in the values assigned to the prize affect alliances in terms of individual nation contributions, total contributions, burden sharing, and the likelihood of winning the prize. While there was substantial variation in individual behavior, the results of the experiments generally conform to the theoretical predictions of the rent‐seeking model of international competition and alliances.  相似文献   
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Five Myths about Nuclear Weapons, by Ward Wilson. Houghton Mifflin Harcourt, 2013. 188 pages, $22.  相似文献   
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Consider two machines, labeled 1 and 2. A set of tasks has to be processed first on machine 1 and after that on machine 2. A second set of tasks has to be processed first on machine 2 and after that on machine 1. All the processing times are exponentially distributed. We present a policy which minimizes the expected completion time of all tasks.  相似文献   
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