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171.
A framework involving independent competing risks permits observing failures due to a specific cause and failures due to a competing cause, which constitute survival times from the cause of primary interest. Is observing more failures more informative than observing survivals? Intuitively, due to the definitiveness of failures, the answer seems to be the former. However, it has been shown before that this intuition holds when estimating the mean but not the failure rate of the exponential model with a gamma prior distribution for the failure rate. In this article, we address this question at a more general level. We show that for a certain class of distributions failures can be more informative than survivals for prediction of life length and vice versa for some others. We also show that for a large class of lifetime models, failure is less informative than survival for estimating the proportional hazards parameter with gamma, Jeffreys, and uniform priors. We further show that, for this class of lifetime models, on average, failure is more informative than survival for parameter estimation and for prediction. These results imply that the inferential purpose and properties of the lifetime distribution are germane for conducting life tests. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
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We investigate the solvability of two single‐machine scheduling problems when the objective is to identify among all job subsets with cardinality k,1≤kn, the one that has the minimum objective function value. For the single‐machine minimum maximum lateness problem, we conclude that the problem is solvable in O(n2) time using the proposed REMOVE algorithm. This algorithm can also be used as an alternative to Moore's algorithm to solve the minimum number of tardy jobs problem by actually solving the hierarchical problem in which the objective is to minimize the maximum lateness subject to the minimum number of tardy jobs. We then show that the REMOVE algorithm cannot be used to solve the general case of the single‐machine total‐weighted completion time problem; we derive sufficient conditions among the job parameters so that the total weighted completion time problem becomes solvable in O(n2) time. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 449–453, 2013  相似文献   
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Charles Ted Rutledge Bohannan (1914–1982) became an integral agent of US counterinsurgency operations during the early Cold War, contributing to both the success of the COIN effort to defeat the communist Huk insurgents in the Philippines and the stalled COIN efforts in Vietnam. In the early 1960s, he wrote a short and compact analysis of the US and Filipino experience of guerrilla warfare, from the Philippine–American war until the defeat of the Huk Rebellion. It was never published. Reprinted here, Bohannan's analysis of lessons learned makes a substantial contribution to the history of American ideas of unconventional warfare by an expert who contributed these lessons to the successful defeat of an insurgency in South East Asia.  相似文献   
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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   
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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   
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This essay traces the image of Germany that emerges from the reports of Colonel Frederick Trench (1857–1942), British military attache in Berlin from 1906 to 1910. At this time, the British Army possessed only the most limited intelligence‐gathering apparatus and had to rely heavily on the reports of military attaches for information about their continental rivals. Trench, who believed that Germany planned to wage war against Britain and said so categorically in his reports, was the main source of data on the German Army. From the limited surviving records of who read these reports and how they responded to them, this essay posits that Trench's views contributed to the growing British perception of a German threat, a perception that did much to influence British strategic planning in this period.  相似文献   
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