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101.
It is known that the proportionate flow shop minimum makespan F m / p r p t / C max problem is solved optimally by any permutation job sequence. We show that the F m / p r p t / C max problem is at least ordinary NP‐hard when missing operations are allowed and present some solvable cases. We then consider the standard proportionate flow shop problem (with no missing operations) and show that the solution algorithms for a class of single‐machine due date assignment problems can be extended/generalized to the corresponding proportionate flow shop problems. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 98–106, 2015  相似文献   
102.
Abstract

This article surveys China’s current naval forces and considers key dynamics and possible Chinese naval futures to 2020, the projected end of Beijing’s ‘strategic window of opportunity’, the idea that a peaceful external environment for economic development, globalization, and integration of China into the global economy allows China to benefit from diversion of US attention to countering terrorism. It considers broad possibilities through 2030, the general limit of public US government projections, and by which time multiple factors will likely slow China’s growth and compete for leadership focus and resources.  相似文献   
103.
Famous cultural monuments are often regarded as unique icons, making them an attractive target for terrorists. Despite huge military and police outlays, terrorist attacks on important monuments can hardly be avoided. We argue that an effective strategy to discourage terrorist attacks on iconic monuments is for a government to show a firm commitment to swift reconstruction. Using a simple game‐theoretic model, we demonstrate how a credible claim to rebuild any destroyed cultural monument discourages terrorist attacks by altering the terrorists' expectations and by increasing the government's reputation costs if they fail to rebuild.  相似文献   
104.
This paper aims at forecasting the burden on the Greek economy resulting from the arms race against Turkey and at concentrating on the leading determinants of this burden. The military debt and the defence share of GDP are employed alternatively in order to approximate the measurement of the arms race pressure on Greece, and the method used is that of artificial neural networks. The use of a wide variety of explanatory variables in combination with the promising results derived, suggest that the impact on the Greek economy resulting from this arms race is determined, to a large, extent, by demographic factors which strongly favour the Turkish side. Prediction on both miltary debt and defence expenditure exhibited highly satisfactory accuracy, while the estimation of input significance, indicates that variables describing the Turkish side are often dominant over the corresponding Greek ones.  相似文献   
105.
This paper investigates the potential for modeling and simulation to contribute to new defense system development, by increasing the productivity of traditional R&D in developing system‐specific technology. Building on a previous optimal control model of defense system R&D, it shows that (1) the optimal use of modeling is related in a natural way to that of traditional R&D, and (2) both have similar optimal profiles over time. Simulated results based on limited historical data suggest that optimal use of modeling could increase the rate of growth in system‐specific technology significantly.  相似文献   
106.
1 1This research was funded in part by a grant from the Lowe Institute of Political Economy. The corresponding author is S. Brock Blomerg. We thank Chris Blomberg and Brianna Loyosa for their excellent research assistance on the project. This paper presents an empirical analysis of what drives congressional legislation on terrorism during the period 1995 to 2010. We utilize and augment current methodology to compile and analyze data on sponsorship and cosponsorship of terrorism related data. Our results on the sources of legislation on terrorism are largely in line with past examinations of the importance of committee membership and leadership, party majority-ship, and other political factors. Further, we find that the most significant and robust drive for legislation on terrorism is the September 11th attacks. And while the impact of 9/11 affected legislative productivity everywhere, we find that it most significantly affected states surrounding New York and Washington D.C. Our results indicate that the economy may be one factor motivating politicians to legislate on terrorism; however, these results are not robust.  相似文献   
107.
Export controls and international safeguards are central to ensuring international confidence in the peaceful uses of nuclear materials and technologies and to achieving adequate oversight on the transfer and use of nuclear materials, technology, and equipment required for the development of proliferation-sensitive parts of the nuclear fuel cycle. Although the independent strengths of export controls and international safeguards rely largely on universal adherence, there may be opportunities to exploit the shared strengths of these systems. This article provides background information on the separate evolution of export controls and international safeguards, considers how these two elements of the nonproliferation regime interact, and identifies some possible avenues that could, over time, lead to wholly integrated activities.  相似文献   
108.
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   
109.
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   
110.
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