In this article an algorithm for computing upper and lower ? approximations of a (implicitly or explicitly) given convex function h defined on an interval of length T is developed. The approximations can be obtained under weak assumptions on h (in particular, no differentiability), and the error decreases quadratically with the number of iterations. To reach an absolute accuracy of ? the number of iterations is bounded by
Abstract What are the consequences of military strikes against nuclear facilities? In particular, do they ‘work’ by delaying the target states ability to build the bomb? This article addresses these questions by conducting an analysis of 16 attacks against nuclear facilities from 1942 to 2007. We analyze strikes that occurred during peacetime and raids that took place in the context of an ongoing interstate war. The findings indicate that strikes are neither as uniformly fruitless as the skeptics would suggest, nor as productive as advocates have claimed. There is evidence that the peacetime attacks delayed the target's nuclear program, although the size of this effect is rather modest. The wartime cases were less successful, as attacks often missed their targets either due to operational failure or limited intelligence on the location of critical targets. In our concluding section we show that many of the conditions that were conducive to past success are not present in the contemporary Iran case. Overall, our findings reveal an interesting paradox. The historical cases that have successfully delayed proliferation are those when the attacking state struck well before a nuclear threat was imminent. Yet, this also happens to be when strikes are the least legitimate under international law, meaning that attacking under these conditions is most likely to elicit international censure. 相似文献
This article challenges the conventional wisdom that Neville Chamberlain rejected the British tradition of balance of power in the 1930s. In contrast to balance of power and balance of threat theories, states do not balance against aggregate or net shifts in power. Instead, leaders define threats based on particular elements of a foreign state's power. The import is that different components of power of a foreign state are more or less threatening and aggregate shifts in power alone may not provoke counterbalancing behavior. In the 1930s, Britain balanced against the most threatening components of power: the German Luftwaffe and the threat of a knock-out air assault against the homeland, Japan's Imperial Navy and its threat to Britain's commercial trade routes and the Dominions in East Asia, and the Italian Navy and the threat to Britain's line of communication through the Mediterranean Sea to India and Asia. Given Britain's difficult financial circumstances, all other components of power, such as the army and the land components of power of Germany, Japan, and Italy were ranked as secondary in terms of its rearmament priorities. Thus, London was able to narrow the gap with Berlin in specific components of power of strategic importance such as aircraft production or to exceed Germany in other areas such as the Royal Navy and its battlefleet. 相似文献