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281.
282.
To solve linear fixed charge problems with Murty's vertex ranking algorithm, one uses a simplex algorithm and a procedure to determine the vertices adjacent to a given vertex. In solving fixed charge transportation problems, the simplex algorithm simplifies to the stepping-stone algorithm. To find adjacent vertices on transportation polytopes, we present a procedure which is a simplification of a more general procedure for arbitrary polytopes. 相似文献
283.
We consider the nonpermutation flow shop problem with release dates, with the objective of minimizing the sum of the weighted completion times on the final machine. Since the problem is NP‐hard, we focus on the analysis of the performance of several approximation algorithms, all of which are related to the classical Weighted Shortest Processing Time Among Available Jobs heuristic. In particular, we perform a probabilistic analysis and prove that two online heuristics and one offline heuristic are asymptotically optimal. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005. 相似文献
284.
David Brewster 《战略研究杂志》2013,36(6):825-852
Since the end of the Cold War, India's strategic horizons have moved beyond its traditional preoccupations in South Asia. India is developing a strategic role in East Asia in particular. At the same time India's strategic thinking has undergone a revolution, as the country that prided itself on non-alignment has moved closer to the West. But India's culture, history and geography still fundamentally shape its worldview. In engaging with East Asia, India is guided by a mosaic of strategic objectives about extending its sphere of influence, developing a multipolar regional system and balancing against China. The interplay of these objectives will frame India's role in East Asia in coming years. 相似文献
285.
This study examines the problems of paramilitary decommissioning in Northern Ireland. It analyses why decommissioning has become so contentious in the Northern Ireland peace process. Decommissioning, though, is not a unique or intrinsically insurmountable problem. This is demonstrated by highlighting the issue in international context. Three examples of decommissioning in conflict resolution processes are assessed: the Lebanon, El Salvador and Mozambique. These varied examples do supply some limited lessons for Northern Ireland. This study argues that the explanation for the intractability of decommissioning in Northern Ireland resides, to a greater extent, in the tactical and strategic reasoning of the main paramilitary groupings in Northern Ireland. The factors that condition their thinking, however, can be found in the nature of the peace process itself which provides the paramilitiaries with every incentive to retain possession of their weapons. 相似文献
286.
This study investigates the ricochet behaviour of three different small-arms projectile types using a novel ricochet measuring device.The results can be used to estimate the danger potential of ricochets on shooting ranges.A ricochet is the change of direction and velocity of a projectile after impacting an oblique surface.This impact produces strong vibrations on a rigid plate.During this impact,flexural waves travel radially outwards from the point of impact.These waves are used to determine the properties of the impactor with accelerometers situated on the target surface.With the use of two measurement plates,one can produce a ricochet and detect the velocity at the same time.Accelerometers are suitable for accurate momentum measurements of single impacts.However,depending upon strike velocity and the impact angle,a ricochet can separate in multiple fragments after being deflected.From the operational safety perspective,these fragments need to be detected,as well.The approach of a coupled sensor concept was chosen to solve this problem.Thermographic sensors were additionally used to visualise the heat which is produced after pene-trating a rubber layer pasted in front of the steel target plate.With this approach one was able to detect the position of impact.The investigations showed that the measurement system performance is better with a multiple sensor design,which includes accelerometers for the velocity,impact strength and partly the position measurement,while the thermographic sensor was used for the position measurement and partly the momentum measurement.The investigated ammunition showed plausible fragmentation behaviour,and the results can already be used to estimate the danger potential of different ammunition types.Frangible projectiles fragment to small particles already after being deflected under a small angle.However,Full Metal Jacket projectiles with or without a steel core do not fragment under angles which are less than 5°.The objective of the paper is to demonstrate the possibility of measuring the complex ricochet me-chanics of small projectiles using standard accelerometers with the adequate signal processing approach.This measuring system is supported by an off the shelf thermographic camera. 相似文献
287.
Justin O. Smith 《Small Wars & Insurgencies》2013,24(3):448-466
A comprehensive maritime interdiction strategy to attack the insurgent's logistic system was a key element in the defeat of the Tamil Tigers. The campaign of maritime interdiction required the Sri Lankan Navy (SLN) to attack LTTE arms smuggling, sea piracy, and maritime terrorism. The SLN degraded the insurgency's robust maritime logistical network while also devising tactics to engage the maritime insurgents who reacted with swarm and suicide boat tactics. The efforts of the SLN forced the Tamil Tigers to confront the government's final land offensives with diminished resources, thus collapsing a three decades’ old insurgency in a matter of months. 相似文献
288.
Ron Smith 《Whitehall Papers》2013,80(1):36-59
Abstract Ron Smith looks at procurement procedures within a European context, taking account of the problems currently facing defence industries and aduocates the institution of a European Defence Union, to be closely monitored by a joint finance Ministry to prevent overspending and monopoly. 相似文献
289.
David C. Dellinger 《海军后勤学研究》1971,18(3):357-378
A linear programming application for the selection of aircraft for a tactical airlift fleet is described. 相似文献
290.