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How do we assess the health of international regimes? Many analysts have insisted recently that the nuclear nonproliferation regime is in urgent need of repair or that it should even be discarded because of its supposed ineffectiveness. However, it is essential that statements about the regime being in crisis be scrutinized for veracity and utility. While the spread of nuclear weapons poses an undeniable and serious threat to international security, a mistaken crisis mentality with respect to the regime could lead to rash attempts to alter it in unnecessary or ineffective ways or, at worst, to discard it completely. This paper returns to a theoretical framework that differentiates regimes, across both issue areas and time, to provide a more specified evaluation of regime health. By disaggregating the nuclear nonproliferation regime and assessing the individual and interactive health of multiple dimensions, a number of dimension-specific, regime-strengthening policy recommendations emerge. 相似文献
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Jeffrey Kaplow 《The Nonproliferation Review》2013,20(2):185-202
ABSTRACTThe Treaty on the Non-Proliferation of Nuclear Weapons (NPT) allows states to exempt nuclear material from international safeguards for use in nuclear submarine programs. This material, however, could be diverted for nuclear weapons purposes without the knowledge of inspectors, creating a potentially dangerous loophole in the treaty. This article argues that exercising that loophole today would amount to admitting a nuclear weapon program, making it a particularly poor pathway to a weapon for a potential proliferant. Still, if states like Brazil ultimately exempt nuclear material from safeguards for a nuclear submarine effort, they could set a dangerous precedent that makes it easier for others to use the loophole as a route to a nuclear weapon capability. There are several policy options available to mitigate the damage of such a precedent; most promising is the prospect of a voluntary safeguards arrangement that would allow international inspectors to keep an eye on nuclear material even after it has been dedicated to a naval nuclear propulsion program. 相似文献
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Jeffrey S. Lantis 《The Nonproliferation Review》2013,20(2):389-409
The 2010 Review Conference of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) produced a Final Document calling for an extension of the principles of the nonproliferation norm as well as steps toward complete disarmament. This article looks beyond the rhetoric, however, to examine recent decisions by great powers to expand nuclear trade with non-NPT countries and the implications of these decisions on the traditional nonproliferation norm of restraint. This article seeks to contribute to constructivist theory by supplementing existing accounts of norm creation and establishment with a new model of norm change. The article develops a case study of the 2008 US-India nuclear deal to highlight the role of elite agency in key stages of norm change, including redefinition and constructive substitution through contestation. It concludes that the traditional nonproliferation norm may be evolving in new directions that are not well captured by existing theoretical frames. 相似文献
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Consider the conditional covering problem on an undirected graph, where each node represents a site that must be covered by a facility, and facilities may only be established at these nodes. Each facility can cover all sites that lie within some common covering radius, except the site at which it is located. Although this problem is difficult to solve on general graphs, there exist special structures on which the problem is easily solvable. In this paper, we consider the special case in which the graph is a simple path. For the case in which facility location costs do not vary based on the site, we derive characteristics of the problem that lead to a linear‐time shortest path algorithm for solving the problem. When the facility location costs vary according to the site, we provide a more complex, but still polynomial‐time, dynamic programming algorithm to find the optimal solution. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005. 相似文献
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This paper discusses a novel application of mathematical programming techniques to a regression problem. While least squares regression techniques have been used for a long time, it is known that their robustness properties are not desirable. Specifically, the estimators are known to be too sensitive to data contamination. In this paper we examine regressions based on Least‐sum of Absolute Deviations (LAD) and show that the robustness of the estimator can be improved significantly through a judicious choice of weights. The problem of finding optimum weights is formulated as a nonlinear mixed integer program, which is too difficult to solve exactly in general. We demonstrate that our problem is equivalent to a mathematical program with a single functional constraint resembling the knapsack problem and then solve it for a special case. We then generalize this solution to general regression designs. Furthermore, we provide an efficient algorithm to solve the general nonlinear, mixed integer programming problem when the number of predictors is small. We show the efficacy of the weighted LAD estimator using numerical examples. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006 相似文献
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Disruptions in the production process can have a serious impact on production costs. Most of the previous literature which addresses the cost impact of production breaks attributes the observed increase in costs solely to “loss of learning.” We develop a mathematical model which implies that breaks in the unit learning curve can occur because of a production break, even under the assumption of no forgetting. In such cases, increases in unit cost can be caused by decreasing returns as the amount of time available to meet the delivery schedule decreases due to the production break. 相似文献