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171.
The notions of minimax paths, trees, and cut sets are defined for undirected graphs; and relationships between these entities are established. Simple solution procedures based on these relationships are presented. 相似文献
172.
Moment estimators for the parameters of the Weibull distribution are considered in the context of analysis of field data. The data available are aggregated, with individual failure times not recorded. In this case, the complexity of the likelihood function argues against the use of maximum-likelihood estimation, particularly for relatively large sets of data, and moment estimators are a reasonable alternative. In this article, we derive the asymptotic covariance matrix of the moment estimators, and provide listings for BASIC computer programs which generate tables useful for calculation of the estimates as well as for estimating the asymptotic covariance matrix using aggregated data. 相似文献
173.
Ulrich Kühn 《The Nonproliferation Review》2019,26(1-2):155-166
The end of the 1987 Intermediate-range Nuclear Forces (INF) Treaty has the potential to plunge Europe and NATO into deep crisis. Russia’s continued violation coupled with the Donald J. Trump administration’s desire to balance against Moscow and Beijing could force a new missile debate on Europeans. Even though Washington is trying to assuage its allies, the specter of another round of INF missile deployments to Europe is not unrealistic. Meanwhile, NATO’s European members face a dilemma. Some want NATO to resolutely push back against Russia. Others want to avoid a new deployment debate, at almost all costs. The Kremlin will use these cleavages to weaken NATO. If not carefully handled, NATO’s response to the Russian missile buildup could lead to domestic turmoil in a number of European states and render the alliance ineffective for a prolonged period. Europeans need to act now and voice their preferences in the military and diplomatic domains. A number of different military options are available, below the level of deploying new INF missiles in Europe. However, Europeans need to consider trade-offs regarding crisis and arms-race stability. At the same time, it will be up to European capitals to conceptualize a new arms-control framework for the post-INF world, one that takes into account today’s geopolitical realities and the entanglement of modern conventional and nuclear forces. Given the Trump administration’s loathing of arms control, concepts of mutual restraint may well have to wait for the next US administration. In any case, that should not stop Europeans from taking on more responsibility for their own security. 相似文献
174.
175.
Tilman Brück 《Defence and Peace Economics》2013,24(5):375-389
This paper analyses public policy choices in the security economy from an economic perspective. It discusses the role of public goods for national and global security and identifies the importance of the first‐ and second‐order indirect effects of insecurity on economic activity, which include the behavioural responses of agents and the government to security measures, akin to such effects in insurance economics. Furthermore, key public policy trade‐offs are outlined, in particular between security and efficiency, globalisation, equity and freedom. The analysis identifies suitable policy options for raising security in the national and international contexts and in view of these trade‐offs. A balance between market and non‐market instruments in achieving security should be aimed for in order to minimise the adverse effects of aiming for higher security. In addition, the public good nature of security implies that international coordination of security policies is important, despite this process being fraught with enforcement problems. 相似文献
176.
W. Robert J. Alexander 《Defence and Peace Economics》2013,24(2):213-221
The issue of guns or butter is one of the most fundamental economic questions, yet there is no consensus on a theoretical framework for examining it. Over the last decade, a version of a simple Keynesian macroeconomic model has been applied a number of times to examining the link between defence spending and economic growth in a range of countries. There are reasons for doubting the soundness of this model as a basis for empirical work. 相似文献
177.
178.
We study how changes to the composition and employment of the US Navy combat logistic force (CLF) influence our ability to supply our navy worldwide. The CLF consists of about 30 special transport ships that carry ship and aircraft fuel, ordnance, dry stores, and food, and deliver these to client combatant ships underway, making it possible for our naval forces to operate at sea for extended periods. We have modeled CLF operations to evaluate a number of transforming initiatives that simplify its operation while supporting an even larger number of client ships for a greater variety of missions. Our input is an employment schedule for navy battle groups of ships operating worldwide, extending over a planning horizon of 90–180 days. We show how we use optimization to advise how to sustain these ships. We have used this model to evaluate new CLF ship designs, advise what number of ships in a new ship class would be needed, test concepts for forward at‐sea logistics bases in lieu of conventional ports, demonstrate the effects of changes to operating policy, and generally try to show whether and how the CLF can support planned naval operations. Published 2008 Wiley Periodicals, Inc. Naval Research Logistics 2008 相似文献
179.
Jeffrey W. Knopf 《Contemporary Security Policy》2017,38(1):26-34
Comments that Donald Trump made while campaigning to be U.S. president have raised concerns that his administration will pull back from U.S. alliance commitments and encourage countries such as Japan and South Korea to acquire nuclear arms. The new article by Frühling and O’Neil outlines an institutional framework that can be helpful in assessing the risks that Trump administration policies will lead to nuclear proliferation. An institutional perspective shows that important elements of U.S. security assurances will continue to function, and this reduces the chances that President Trump’s actions or statements will trigger proliferation by U.S. allies. The greatest risk to global non-proliferation efforts posed by a Trump administration in fact lies elsewhere, in the possibility that President Trump will seek to abrogate the Iran nuclear deal. 相似文献
180.
W. Alejandro Sanchez Nieto 《Small Wars & Insurgencies》2013,24(4):573-587
After decades of fighting, the secessionist war between the government of Sri Lanka and the secessionist movement known as the Tamil Tigers of Eelam continues. Military operations have failed to achieve a decisive victory over the other side. This article aims to prove that the Sri Lankan civil war should be regarded as a war of attrition, as military actions have failed, and possibly will continue to fail, to produce a victor. 相似文献