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One goal of experimentation is to identify which design parameters most significantly influence the mean performance of a system. Another goal is to obtain good parameter estimates for a response model that quantifies how the mean performance depends on influential parameters. Most experimental design techniques focus on one goal at a time. This paper proposes a new entropy‐based design criterion for follow‐up experiments that jointly identifies the important parameters and reduces the variance of parameter estimates. We simplify computations for the normal linear model by identifying an approximation that leads to a closed form solution. The criterion is applied to an example from the experimental design literature, to a known model and to a critical care facility simulation experiment. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004  相似文献   
554.
In a multifunction radar, the maximum number of targets that can be managed or tracked is an important performance measure. Interleaving algorithms developed to operate radars exploit the dead‐times between the transmitted and the received pulses to allocate new tracking tasks that might involve transmitting or receiving pulses, thus increasing the capacity of the system. The problem of interleaving N targets involves a search among N! possibilities, and suboptimal solutions are usually employed to satisfy the real‐time constraints of the radar system. In this paper, we present new tight 0–1 integer programming models for the radar pulse interleaving problem and develop effective solution methods based on Lagrangian relaxation techniques. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004.  相似文献   
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Russia's 2006 renationalisation of its aerospace industry heralded a new era in industrial policy. Symbolising a return to the importance of securing sovereignty over the Federation's strategic assets, it also posits, powerfully, that sectors like aerospace and shipbuilding are too important to be left to the market. In what now appears a reversal of this policy approach, Moscow is promoting partial privatisation and encouraging partnership with Western aerospace companies. Foreign infusion of capital and technology is viewed as the catalyst for Russian dominance in the global military and commercial aerospace industries.  相似文献   
557.
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   
558.
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   
559.
This study examines the problems of paramilitary decommissioning in Northern Ireland. It analyses why decommissioning has become so contentious in the Northern Ireland peace process. Decommissioning, though, is not a unique or intrinsically insurmountable problem. This is demonstrated by highlighting the issue in international context. Three examples of decommissioning in conflict resolution processes are assessed: the Lebanon, El Salvador and Mozambique. These varied examples do supply some limited lessons for Northern Ireland. This study argues that the explanation for the intractability of decommissioning in Northern Ireland resides, to a greater extent, in the tactical and strategic reasoning of the main paramilitary groupings in Northern Ireland. The factors that condition their thinking, however, can be found in the nature of the peace process itself which provides the paramilitiaries with every incentive to retain possession of their weapons.  相似文献   
560.
Most historical accounts of the atomic bombings of Japan show little interest in Britain's explicit authorization for the attacks. Meanwhile, the few historians who have attempted to explain it rely on a unitary, rational actor model of the British state that is misleading. This article demonstrates that high-ranking British officials became anxious early on about the strategic consequences of a peremptory use of the new weapon. Therefore, especially over the course of 1944 they sought to engage Washington on the linked questions of the bomb's wartime use and its postwar control. However, these officials' initiatives were rebuffed by Prime Minister Winston Churchill, who paved the way to the bombings based on a fervent desire for Anglo-American integration, and on a dim understanding of the bomb's revolutionary potential.  相似文献   
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