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191.
Full‐system testing for large‐scale systems is often infeasible or very costly. Thus, when estimating system reliability, it is desirable to use a method that uses subsystem tests, which are often less expensive and more feasible. This article presents a method for bounding full‐system reliabilities based on subsystem tests and, if available, full‐system tests. The method does not require that subsystems be independent. It accounts for dependencies through the use of certain probability inequalities. The inequalities provide the basis for valid reliability calculations while not requiring independent subsystems or full‐system tests. The inequalities allow for test information on pairwise subsystem failure modes to be incorporated, thereby improving the bound on system reliability. We illustrate some of the properties of the estimates via an example application. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
192.
The German invasion in Norway in April 1940 was unique in that it was the first major ‘triphibious’ campaign. It was an operation that was equally dependent upon naval, air and ground forces for success. Norway had long been of interest to German strategists, especially naval thinkers. However, no serious Wehrmacht plans for occupying Norway were even started until December 1939. A small group of staff officers of the three services put together a comprehensive plan in a matter of weeks. The article examines the effectiveness of the German interservice co‐operation and OKW leadership in a very tough and close run campaign. Although there were numerous problems, interservice co‐operation was fairly effective at the tactical and operational levels. Indeed, the Germans won the campaign largely because their services worked together much better than their Allied opponents.  相似文献   
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An analysis of US assessments of Germany's development of armored warfare illustrates the problems that intelligence agencies face as they attempt to understand military innovation. The covert nature of German Army's tank research in the years immediately following World War I limited the number of indicators of Berlin's interest in armored warfare. Similarly, the United States possessed at best a fragmentary picture of German experimentation with armor. By the outbreak of World War II, however, US military attaches had nonetheless developed an accurate understanding of German concepts of armored warfare. If the United States is to avoid strategic surprise in the future, it must cultivate intelligence sources and employ considerably different methods from those of the Cold War.  相似文献   
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The 1940 Norway campaign was the first truly modern joint operation in which ground, sea and air forces all played major roles. With three services involved over a huge theater of war, the normal friction in obtaining and disseminating intelligence and information that one finds in a joint operation was multiplied. As the two sides were fairly evenly matched, effective use of intelligence and information provided a decisive advantage. This paper analyzes the use of information and intelligence of both sides at the strategic, operational and tactical levels. Both sides performed poorly at the strategic level but the Germans proved far superior to the British at the operational and tactical levels. The paper challenges several common assumptions on the importance of intelligence and information in joint campaigns.  相似文献   
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Dying to Win is one of the most important works on suicide terrorism. It purports to unravel the strategic, social, and individual logic that gives suicide terrorism its coercive value. The methodology that Pape uses to support his various assertions is problematic for three reasons. First, he defines his key terms in such a way as to artificially set suicide terrorism apart from other forms of political violence. Second, in a number of cases Pape selects data from single sources to support particular assertions when other sources of data, used together, could provide more rigorous and useful insights into the phenomenon of suicide bombing. Finally, Pape codes his data on suicide attacks according to a loose set of criteria which, if recoded, calls into question some of his broader conclusions about the strategic utility of suicide terrorism campaigns.  相似文献   
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This paper presents a modified analytical model to evaluate the trajectories of various lift separation sabot configurations. The aerodynamic forces acting on the sabot surfaces during a supersonic flight are modeled in the present analytical model by incorporating the pressures on the windward side of the sabot due to the detached/attached shock and its reflections and then integrated using the 3-DoF dynamical equations. The trajectory and the aerodynamic coefficients were obtained for these config-urations at a projectile Mach number of 3. The sabot configurations, which include two new designs, are compared with each other and with the conventional free flight trajectory data of the conventional sabots. The mechanical interaction between the sabot and projectile is also addressed in the present work. The comparison shows that the new designs with the aerodynamic surfaces close to the center of gravity, lift-off from the projectile with minimal mechanical interaction compared to a conventional sabot.  相似文献   
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