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Nuclear deterrence and cyber war seem almost antithetical in their respective intellectual pedigrees. Nuclear weapons are unique in their ability to create mass destruction in a short time. Information or “cyber” weapons, at least for the most part, aim at sowing confusion or mass disruption instead of widespread physical destruction. Nevertheless, there are some intersections between cyber and nuclear matters, and these have the potential to become troublesome for the future of nuclear deterrence. For example, cyber attacks might complicate the management of a nuclear crisis. As well, information attacks on command-control and communications systems might lead to a mistaken nuclear launch based on false warnings, to erroneous interpretations of data or to panic on account of feared information blackout. It is not inconceivable that future nuclear strike planning will include a preliminary wave of cyber strikes or at least a more protracted “preparation of the battlefield” by roaming through enemy networks to plant malware or map vulnerabilities.  相似文献   
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In this article, we address a stochastic generalized assignment machine scheduling problem in which the processing times of jobs are assumed to be random variables. We develop a branch‐and‐price (B&P) approach for solving this problem wherein the pricing problem is separable with respect to each machine, and has the structure of a multidimensional knapsack problem. In addition, we explore two other extensions of this method—one that utilizes a dual‐stabilization technique and another that incorporates an advanced‐start procedure to obtain an initial feasible solution. We compare the performance of these methods with that of the branch‐and‐cut (B&C) method within CPLEX. Our results show that all B&P‐based approaches perform better than the B&C method, with the best performance obtained for the B&P procedure that includes both the extensions aforementioned. We also utilize a Monte Carlo method within the B&P scheme, which affords the use of a small subset of scenarios at a time to estimate the “true” optimal objective function value. Our experimental investigation reveals that this approach readily yields solutions lying within 5% of optimality, while providing more than a 10‐fold savings in CPU times in comparison with the best of the other proposed B&P procedures. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 131–143, 2014  相似文献   
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This study examines the effects of home-state unemployment rates on attrition behavior of Navy enlistees for successive career windows during the first term of service: the first 6?months, the second 6?months, the second year, and the third year of service. The results indicate that attrition is negatively associated with changes in the local unemployment rate during the first three career windows covering two years of service. However, after two years of service, the estimated effect of the unemployment rate becomes insignificant for most groups of sailors. This is likely because sailors with the poorest job matches are sorted out early in the first term of service.  相似文献   
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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   
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The stage may be set for what could be a historic turning point in America's reliance on nuclear weapons to meet its fundamental national security interests. Proponents of a refurbished nuclear stockpile and infrastructure are convinced that nuclear weapons will remain central to U.S. security interests, yet they admit that there is no national consensus on the need for and role of nuclear weapons. Nuclear opponents are gravely concerned that to the extent nuclear refurbishment creates a global perception that nuclear weapons remain essential instruments, it will eviscerate nuclear nonproliferation measures precisely at a time when nuclear ambitions are growing. Moreover, opponents see deterrence through advanced conventional weapons as decisively more credible than any nuclear alternative. With hopes of elevating discourse to the national level, this article examines the key current arguments pro and con within the specialist community and forecasts changes in the U.S. nuclear arsenal over the next decade. It concludes with a brief prognosis on prospects for complete nuclear disarmament.  相似文献   
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CONTRIBUTORS     
ABSTRACT

Narratives about Brazil's nuclear program are distorted by supporters and critics alike. In Brazil, the national nuclear infrastructure is undergoing a period of expansion, with plans to build new nuclear power plants and industrial-scale fuel production facilities. While Brazil's leaders herald the nuclear sector as a triumph for indigenous science and technology, foreigners view the nuclear program as a dangerous legacy of the military regime. This discrepancy becomes even more apparent in discussions about the ongoing construction of Brazil's first nuclear powered submarine. Brazil's military touts the submarine as a symbol of political status, economic growth, and military might. But from abroad, the military's involvement in nuclear development is considered unnecessary, worrisome, and even irresponsible. These narratives—often incomplete or selective—have polarized discussions about Brazil's nuclear submarine program and caused considerable political antagonism during safeguards negotiations. This article works to dispel myths, highlight legitimate concerns, and explain historical perspectives that shed light on some difficulties that can be anticipated in future negotiations.  相似文献   
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This article argues that the prewar planning process for postwar Iraq was plagued by myriad problems, including a dysfunctional interagency process, overly optimistic assumptions, and a lack of contingency planning for alternative outcomes. These problems were compounded by a lack of civilian capacity during the occupation period, which led to a complicated and often uncoordinated relationship with the military authorities who found themselves taking the lead in many reconstruction activities. Taken together, these mistakes meant that US success on the battlefield was merely a prelude to a postwar insurgency whose outcome remains very much in doubt more than three years later.  相似文献   
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