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51.
ABSTRACT

From 1944 to 1973 Australia attempted to acquire atomic weaponry. This ambition was driven by the desire to contribute to defending British interests in Asia, fears of invasion by China, Indonesia, and Japan, great-power war, and the belief that nuclear weapons were merely bigger and better conventional weapons, that they would proliferate, and that US security assurances lacked credibility. Although the pursuit of the bomb was eventually abandoned, this was not the result of US assurances. Rather, geopolitical changes in Australia’s environment meant that a major attack on the continent was unlikely to occur outside the context of a confrontation between the US, China, and the Soviet Union. This article argues that Australia may soon have to rethink its policies towards US extended deterrence and instead focus on developing its own deterrent.  相似文献   
52.
The effort to degrade and defeat the Islamic State is like many other multilateral military efforts – characterized by widely varying contributions to the effort. This article seeks to understand the patterns of contributions. Three sets of explanations are applied: the lessons of Afghanistan and Libya, variations in how potential contributors feel the threat posed by the Islamic State, and domestic political dynamics. While there may be some political processes that overlap with the big lessons and with the threat of the Islamic State, the patterns of contributions thus far suggest that the key drivers of reactions to the Islamic State are the desire not to repeat Afghanistan combined with some impetus provided by Islamic State attacks in the various homelands. The conclusion suggests some policy implications as well as some ideas for future research.  相似文献   
53.
Lobbyists may not share the same interests, but they usually agree to form a link in a network which could eventually be used to spread information, to search for potential partners, to speak with one voice to decision makers. In other words, social links represent value for lobbyists because they may ultimately facilitate access. In this article, we explore the network of the Security and Defense lobbies in the EU and we describe its structure.  相似文献   
54.
A new class of nonparametric reliability models is introduced and studied. A distribution is said to be better at age s than at age t (sBt) if the residual lifetime at age s is stochastically greater than or equal to the residual lifetime at age t. Applications to various forms of replacement policies, including the cannibalization of failed systems, are noted. For fixed s < t, the problem of estimating a survival curve assumed to belong to the sBt class is addressed using recursive methods. An sBt estimator is derived in closed form, and its uniform strong consistency at an optimal rate of convergence is demonstrated. A simulation study strongly supports the claim that the sBt estimator tends to outperform the empirical survivor function in small- and moderate-size samples. © 1993 John Wiley & Sons, Inc.  相似文献   
55.
We consider the problem of finding a plan that maximizes the expected discounted return when extracting a nonrenewable resource having uncertain reserves. An extraction plan specifies the rate at which the resource is extracted as a function of time until the resource is exhausted or the time horizon is reached. The return per unit of resource extracted may depend on the rate of extraction, time, and the amount of resource previously extracted. We apply a new method called the generalized search optimization technique to find qualitative features of optimal plans and to devise algorithms for the numerical calculation of optimal plans.  相似文献   
56.
57.
This article develops a robust, exact algorithm for the maximal covering problem (MCP) using dual-based solution methods and greedy heuristics in branch and bound. Based on tests using randomly generated problems with problem parameters similar to those in the existing literature, the hybrid approach developed in this work appears to be effective over a wide range of MCP model parameters. The method is further validated on problems constructed from three real-world data sets. The extensive computational study compares the new method with other existing exact methods using problems that are as big, or larger than, those used in previous work on MCP. The results show that the proposed method is effective in most instances of MCP. In particular, it is shown that bounding schemes using Lagrangian relaxation are effective on MCP as a method of obtaining both exact and heuristic solutions. © 1996 John Wiley & Sons, Inc.  相似文献   
58.
We consider sequencing n jobs on a single machine subject to job completion times arising from either machine breakdowns or other causes. The objective is to minimize an expected weighted combination of due dates, completion times, earliness, and tardiness penalties. The determination of optimal distinct due dates or optimal common due dates for a given schedule is investigated. The scheduling problem for a fixed common due date is considered when random completion times arise from machine breakdowns. The optimality of a V-shaped about (a point) T sequence is established when the number of machine breakdowns follows either a Poisson or a geometric distribution and the duration of a breakdown has an exponential distribution. © 1996 John Wiley & Sons, Inc.  相似文献   
59.
The facility location and capacity acquisition decisions are intertwined, especially within the international context where capacity acquisition costs are location dependent. A review of the relevant literature however, reveals that the facility location and the capacity acquisition problems have been dealt with separately. Thus, an integrated approach for simultaneous optimization of these strategic decisions is presented. Analytical properties of the arising model are investigated and an algorithm for solving the problem is devised. Encouraging computational results are reported. © 1995 John Wiley & Sons, Inc.  相似文献   
60.
We examine the problem of estimating the item fill rate in a periodic inventory system. We show that the traditional expressions for line item fill rate, found in many operations management textbooks, perform well for high fill rates (above 90%), but they consistently underestimate the true fill rate. The problem of underestimation becomes significant as the fill rate falls below 90% and is greatly amplified in cases with very low fill rates (below 50%). We review other more accurate expressions for fill rate, discussing their relative merits. We then develop an exact fill rate expression that is robust for both high and low fill rates. We compare the new expression to others found in the literature via an extensive set of simulation experiments using data that reflect actual inventory systems found at Hewlett-Packard. We also examine the robustness of the expressions to violations in the underlying assumptions. Finally, we develop an alternative fill rate expression that is robust for cases of high demand variability where product returns are allowed. © 1995 John Wiley & Sons, Inc.  相似文献   
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