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181.
The most vital link in a single commodity flow network is that are whose removal results in the greatest reduction in the value of the maximal flow in the network between a source node and a sink node. This paper develops an iterative labeling algorithm to determine the most vital link in the network. A necessary condition for an are to be the most vital link is established and is employed to decrease the number of ares which must be considered.  相似文献   
182.
This article uses a vertex-closing approach to investigate the p-center problem. The optimal set of vertices to close are found in imbedded subgraphs of the original graph. Properties of these subgraphs are presented and then used to characterize the optimal solution, to establish a priori upper and lower bounds, to establish refined lower bounds, and to verify the optimality of solutions. These subgraphs form the foundation of two polynomial algorithms of complexity O(|E| log |E|) and O(|E|2). The algorithms are proven to converge to an optimum for special cases, and computational evidence is provided which suggests that they produce very good solutions more generally. Both algorithms perform very well on problems where p is large relative to the number of vertices n, specifically, when p/n ≥ 0.30. One of the algorithms is especially efficient for solving a sequence of problems on the same graph.  相似文献   
183.
This article provides a Bayes approach for the quality control of a production process which is defined by an M/G/1 queue. An inspection procedure which is jointly optimal from the queue's operational characteristics and quality-control perspectives is found using a queue-inspection renewal cycle analysis (with overall expected profit per unit time as the optimization objective). Numerical results are obtained, highlighting the relationships between quality control and (queue-like) production management.  相似文献   
184.
The 2003 conflict between Iraq and the US-led Coalition resulted in liberation for the country, enabling its citizens to experience freedom they have not had for decades. While the US-led operation was successful, insurgent movements have hindered the reconstruction efforts and the rebuilding of the government in Iraq. The tactics used by these insurgent groups are not that of 'traditional' warfare, therefore the US and Coalition forces adapted their tactics to respond to this new threat. It is argued that with the application of the Manwaring Paradigm (also known as the SWORD Model), the US and Coalition forces successfully responded to the insurgent movements during the period leading up to the Iraqi elections in January 2005.  相似文献   
185.
186.
In this study, a nonlinear three-dimensional hydrocode numerical simulation was carried out using AUTODYN-3D to investigate the effect of blasting of a high explosive material (TNT) against several configurations of the composite structure. Several numerical models were carried out to study the effect of varying the thickness of the walls and the effect of adding an air layer or aluminum foam layer inside two layers of concrete in mitigating the effect of blast waves on the structure walls. The results showed that increasing the thickness of walls has a good effect on mitigating the effect of blast waves. When a layer of air was added, the effect of blast waves was exaggerated, while when a layer of aluminum foam was added the blast wave effects were mitigated with a reasonable percentage.  相似文献   
187.
188.
In the 1990s no-fly zones were introduced as a new way to utilize airpower in the context of Peace Support Operations (PSOs). During that time, they were put to use over Iraq and over Bosnia. However, it is unclear to what extent the no-fly zones were successful in those two instances. This article examines the capabilities of no-fly zones and analyzes the Iraq and Bosnia cases of enforcement. It concludes that no-fly zones can be very effective if properly implemented and offers guidance for policy-makers on how to achieve maximum efficacy.  相似文献   
189.
Rearming Germany was a long and complicated process. It was especially difficult to create a new German air force. The army generals who dominated the Bundeswehr cadre did not even want an air force but rather a small arm air corps. Moreover, Adenauer's defense staff failed to adequately budget or plan for a new air force. As rearmament began, US Air Force leaders, working closely with the small Luftwaffe staff in West Germany's shadow Defense Ministry, basically took charge of the process to ensure that the Germans built a new Luftwaffe on the American model – a large, multipurpose force organized as an independent service and fully integrated into NATO. The first Bundesluftwaffe commanders allied themselves to the Americans, often in opposition to their army comrades, to overcome the political problems caused by Adenauer's poor defense planning and create a modern air force on American lines.  相似文献   
190.
This paper provides a method for solving mixed integer quadratic programs with the help of cutting-plane technique.  相似文献   
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