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991.
Simen A. Ellingsen 《The Nonproliferation Review》2013,20(2):399-402
On Nuclear Terrorism, by Michael Levi. Harvard University Press, 2007. 210 pages, $24.95. 相似文献
992.
讨论一类食饵染病的时滞捕食一被捕食者模型,通过分析特征方程,得到正平衡点局部稳定和Hopf分支存在的条件.同时,应用中一tl,流形定理和规范型理论研究正平衡点处Hopf分支方向和分支周期解的稳定性.最后,通过数值模拟对理论结果进行了说明. 相似文献
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针对系统误差、杂波干扰等对点迹融合处理系统的影响,结合工程实践,提出了一种处理复杂环境下多雷达点迹融合结构框架,给出了存在系统误差情形下的多雷达航迹起始、虚假目标抑制、雷达误差配准等模型和算法。仿真结果表明,提出的框架、模型和算法能够有效处理多雷达点迹融合问题。 相似文献
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998.
《Arms and Armour》2013,10(2):124-135
The paper re-interprets the implement known as the ‘Towton Battle Axe’ allegedly found in the river which borders the Towton Battlefield (1461), Yorkshire, England, and which now resides in Alnwick Castle, Northumberland. The paper provides parallels, in the form of comparisons with other weapons, in order that the Towton implement can be shown to be a modified former halberd dating from the early sixteenth century. It is, therefore, highly unlikely that the implement was used in the famous battle. 相似文献
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《Arms and Armour》2013,10(1):62-69
Once armed with only tooth and nail, humankind has displayed great ingenuity in creating weapons. One class of such artifacts, ‘improvised weapons’, once consisted of such items as a rock or bottle, but in an era of readily available manufactured weapons, now includes items created from spare parts in various environments. Using such a weapon as a case study, this article seeks to explore and analyze the derived artifact and understand it not as a piece of junk, but as a credible design product that provides insight into the designer and the motivations of artifact creation. 相似文献
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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