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For many years, non-nuclear weapons states have sought binding commitments from nuclear armed states that they would not be the victim of either the threat or use of nuclear weapons—so-called negative security assurances (NSAs). The nuclear weapon states have traditionally resisted granting such unconditional NSAs. Recent U.S. efforts to use nuclear deterrence against the acquisition and use by other states of chemical, biological and radiological weapons, however, have further exacerbated this divide. This article analyzes the historical development of NSAs and contrasts U.S. commitments not to use nuclear weapons with the empirical realities of current U.S. nuclear weapons employment doctrines. The authors conclude that NSAs are most likely to be issued as unilateral declarations and that such pledges are the worst possible manner in which to handle the issue of security assurance. 相似文献
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Consider a simulation experiment consisting of v independent vector replications across k systems, where in any given replication one system is selected as the best performer (i.e., it wins). Each system has an unknown constant probability of winning in any replication and the numbers of wins for the individual systems follow a multinomial distribution. The classical multinomial selection procedure of Bechhofer, Elmaghraby, and Morse (Procedure BEM) prescribes a minimum number of replications, denoted as v*, so that the probability of correctly selecting the true best system (PCS) meets or exceeds a prespecified probability. Assuming that larger is better, Procedure BEM selects as best the system having the largest value of the performance measure in more replications than any other system. We use these same v* replications across k systems to form (v*)k pseudoreplications that contain one observation from each system, and develop Procedure AVC (All Vector Comparisons) to achieve a higher PCS than with Procedure BEM. For specific small-sample cases and via a large-sample approximation we show that the PCS with Procedure AVC exceeds the PCS with Procedure BEM. We also show that with Procedure AVC we achieve a given PCS with a smaller v than the v* required with Procedure BEM. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 459–482, 1998 相似文献
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This article examines the problem of simultaneously assigning a common due date to a set of independent jobs and scheduling them on identical parallel machines in such a way that the costs associated with the due date and with the earliness or tardiness of the jobs are minimized. We establish that, for certain values of the due-date cost, an optimal schedule for this problem is also optimal for an early/tardy scheduling problem studied by Emmons. We discuss the solution properties for the two problems, and show that both problems are NP-hard even for two machines. We further show that these problems become strongly NP-hard if the number of machines is allowed to be arbitrary. We provide a dynamic programming solution for the problems, the complexity of which indicates that the problems can be solved in pseudopolynomial time as long as the number of machines remains fixed. Finally, we present the results of a limited computational study. © 1994 John Wiley & Sons, Inc. 相似文献
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Charles Tiplitz 《海军后勤学研究》1975,22(2):411-414
Most researchers have not recognized that the main problem of an economic system is the excessive time it requires to reach equilibrium (and consequent inadequate control). An extension of control theory is applied to the Competitive Equilibrium Model. The calculation shows, in contrast to previous results, full employment, if attained, may be maintained for nonzero periods. However, ill condition and other factors cause a very slow approach to optimum. Consequently, constant social and other changes keep a complex economy far from optimum. 相似文献
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Charles J. Esdaile 《战略研究杂志》2013,36(4):515-552
The Emperor Napoleon I is regarded as one of the greatest generals of all time and, as such, he has attracted an immense bibliography. In spite of this, there have been few studies of him as a strategist: instead, it is simply assumed that it was enough for the Emperor to have conducted an operation for it to have had a logical strategic goal. In this article, however, Napoleon is shown to have been primarily an opportunist, who was frequently guided by the needs of the moment and swayed from his course by circumstance, while it is further suggested that, even considered on their own merits, many of his decisions were faulty in the extreme. 相似文献
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Charles Cogan 《战略研究杂志》2013,36(2):138-158
The American administration was much influenced through the late 1950s by the consequences of decolonisation. Though a nation historically committed to anti-imperialism, members of the American administration became anxious at the extent to which recently independent states were coalescing into a large ‘neutralist’ bloc likely to threaten US interests, particularly in the UN. Washington feared in particular that this Afro-Asian grouping might fall under the sway of the Soviet Union. How best to solve this problem created divisions within the US government about dealing with the Algerian problem: some favoured closer contacts with the FLN; others wished to help the French. In the end by hedging their bets and wishing to broker a solution American governments displeased both sides. 相似文献
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