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251.
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Robert L. Feldman 《Small Wars & Insurgencies》2013,24(2):295-306
Though parts of Somalia appear mired in intractable conflict, both domestic and foreign trade continues. As a result amidst the conflict, corruption, and chaos Somalia's business community is a small force for peace and stability. Thus, efforts directed at enhancing the business community, possibly via the Transitional Federal Government or its successor, could play a small role in improving the situation in this strategically poised country with a very entrepreneurial population. However, such success is far from certain, and numerous other factors besides a strengthened business community would have to occur for Somalia even to begin the journey on the long road to recovery. 相似文献
253.
为研究多孔陶瓷膜过滤阻力,提出了多孔陶瓷膜双向过滤方式,分析了9通道多孔陶瓷膜在双向过滤时的有效过滤面积和通道截面积,建立了过滤阻力关系式。试验结果表明,跨膜压差0.05~0.10 MPa、错流速度1.8 m/s时,浓差极化阻力Rp为主要过滤阻力;跨膜压差0.10~0.25 MPa、错流速度1.0~2.2 m/s时,吸附沉积阻力Rd为主要过滤阻力;跨膜压差0.15 MPa、错流速度2.2~3.0 m/s时,膜自身阻力Rm是主要过滤阻力;增大错流速度能够有效延缓浓差极化的发生,减小吸附沉积层的厚度,减轻膜污染,延长过滤周期。 相似文献
254.
This paper extends traditional production/distribution system analysis to address raw material, factories, and markets located beyond Earth. It explains the eventual advantages of such operations and discusses likely sites in the solar system. It furnishes a typology for production/distribution systems, assessing the fit of each type to space operations. It briefly reviews the physics of orbits. It develops transportation and inventory cost functions for the simplest case of Hohmann trajectories, and for transportation between circular orbits of similar radii using higher‐energy trajectories. These cost functions are used to derive a model of production/distribution system cost, the minimization of which selects an optimal factory location. The paper suggests potential extensions to this work, and concludes with ideas for location research on the novel reaches of extraterrestrial space. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005. 相似文献
255.
This exposition presents two algorithms for linear programs which allow a value change in more than one nonbasic variable at each iteration. The computational formulae are developed and errors which have appeared in the literature are noted. One algorithm is a multiple basis exchange procedure while the second is a feasible direction method. There remain many computational challenges in the area of linear programming and we hope that this investigation will encourage additional work in the directions indicated in this exposition. 相似文献
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Bryan L. Deuermeyer 《海军后勤学研究》1980,27(2):177-185
This paper develops a single period model for a specific class of multiproduct perishable inventory systems where demands are interdependent. This class of inventory systems has the property that there is economic substitution between products. It is shown that the optimal policy has the economic substitution property, and that the rate of substitution is age dependent. The model serves as a generalization of a theorem discovered by Ignall and Veinott. 相似文献
259.
We introduce the notion of comparison of the criticality of two nodes in a coherent system, and devlop a monotonicity property of the reliability function under component pairwise rearrangement. We use this property to find the optimal component arrangement. Worked examples illustrate the methods proposed. 相似文献
260.