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571.
When solving location problems in practice it is quite common to aggregate demand points into centroids. Solving a location problem with aggregated demand data is computationally easier, but the aggregation process introduces error. We develop theory and algorithms for certain types of centroid aggregations for rectilinear 1‐median problems. The objective is to construct an aggregation that minimizes the maximum aggregation error. We focus on row‐column aggregations, and make use of aggregation results for 1‐median problems on the line to do aggregation for 1‐median problems in the plane. The aggregations developed for the 1‐median problem are then used to construct approximate n‐median problems. We test the theory computationally on n‐median problems (n ≥ 1) using both randomly generated, as well as real, data. Every error measure we consider can be well approximated by some power function in the number of aggregate demand points. Each such function exhibits decreasing returns to scale. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 614–637, 2003.  相似文献   
572.
573.
This article argues that the perceived need by NATO to nurture political cohesion within the Alliance during the 1950s resulted in the adoption of strategic concepts that were out-of-step with the military environment in which it was operating. It maintains that the Alliance acquiesced to American leadership on nuclear issues which led to the development of tactical nuclear capabilities at the expense of conventional war-fighting capabilities for the defence of the European Central Front. This resulted in a strategic concept that enhanced political cohesion but was militarily unviable.  相似文献   
574.
China’s rapid economic growth is facilitating massive increases in its military spending and causing increased security concerns in Asia and the Western Pacific. But there is uncertainty over how large China’s military spending is relative to other countries, or how fast it is growing in real terms. We address this issue by deriving a relative military cost price index based on the relative unit costs of inputs. We find that China’s real military spending is much larger than suggested by exchange rate comparisons, and even larger than standard purchasing power parity comparisons. We also find, however, that the real growth of China’s military spending has been smaller than conventionally thought. This is due to rapidly growing wages in China and the large share of personnel in China’s military budget.  相似文献   
575.
To manage their assets at an enterprise level, defense organizations have turned to portfolio theory for the planning, analysis and management of their military forces and materiel. Despite being well established in the commercial sector, the application of portfolio approaches in defense is problematic. The vexatious question for defense of how to define and measure benefits arising is complicated by the increased utility and effectiveness achieved through networking of military forces and the equipment they use. The authors discuss the challenges for defense in using a portfolio approach and propose a conceptual model for dealing with the effects arising from networking with information and communications technologies.  相似文献   
576.
Some have argued that the transatlantic rancor over the Iraq war made cooperation, especially on nonproliferation, unlikely. In contrast, this article, documents post-invasion instances of nonproliferation cooperation, with particular emphasis on the Proliferation Security Initiative and the EU-3 Initiative—the British, French, and German negotiations with Iran over its suspected nuclear activities. In addition to documenting French and British participation in these initiatives, the article analyzes why they have chosen to participate and argues that France and Britain have participated in both efforts because they are committed to avoiding future Iraq-like preventive wars.  相似文献   
577.
578.
The Ministry of Defence (MOD) has published estimates of the number of average full‐time UK industry employees dependent on MOD expenditure and defence exports for a number of years. This paper provides the outcome of a recent review of the process used. The method of deriving MOD and defence export final demand vectors, and calculating from these estimates of direct employment (i.e. that in supplying companies) and indirect employment (i.e. that incurred through the supply chain) are described. Difficulties with the data are explored. Alternative approaches, methods used in other countries and challenges posed by changing MOD administrative systems are briefly discussed.  相似文献   
579.

Estimating demand functions for developing countries before and after the end of the Cold War, Dunne and Perlo-Freeman (2003) found little evidence of any change in the underlying relationship. One concern with their analysis was that the use of cross-section averages might have obscured important time series effects. This paper deals with this issue by analysing their data using static and dynamic panel data methods. This produces evidence of a change in relationship and suggests that the focus in the literature on cross-section analyses has indeed limited our understanding of important dynamic processes at work within countries.  相似文献   
580.
The sectoral production function model of Feder (1983) has been widely used to examine the link between defence spending and economic growth. In this paper, the model, for which too much has been claimed in some past work, is examined, and the case is made for using growth in real non‐defence output rather than growth in real aggregate output (inclusive of military spending) as the dependent variable. Attention is restricted to a small group of OECD countries for which reliable labour force and capital stock (as well as defence) data are obtainable. With non‐defence output as the dependent variable and using only high quality data, no evidence in favour of the underconsumptionist (as opposed to the defence as a burden) position is found.  相似文献   
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