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131.
Igor Khripunov 《The Nonproliferation Review》2013,20(2):275-316
The July 2005 terrorist attacks in London demonstrated the resilience of Western society in the face of low-level conventional terrorism. But the psychological damage from the London bombings would likely pale next to the severe, unpredictable, long-lasting effects of a radiological attack. One unique hazard of radiation exposure beyond the obvious physiological effects is that it is colorless, odorless, and tasteless, making it difficult for ordinary citizens to evaluate, quantify, and rationally understand the dangers confronting them. Radiological weapons stand out among the tools available to terrorists for their capacity to inflict far-reaching psychological damage to civilian populaces well beyond the immediate victims. A possible solution to mitigate the psychological consequences is to build a “resilience culture,” an interlocking set of beliefs, attitudes, approaches, and behaviors that help people fare better in any disaster or extraordinary circumstance. The “all-hazards approach,” which emphasizes the identifiable similarities among the “disaster triad”—that is, natural, accidentally man-made, and intentionally man-made disasters—extends to acts of terrorism and could help demystify the fears associated with radiological terrorist weapons. 相似文献
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为了研究土中爆炸作用下埋地管线的安全问题,利用AUTODYN-2D、AU?TODYN-3D程序,采用程序提供的流固耦合功能和网格映射功能,对爆炸地冲击作用下埋地管线的变形和破坏问题进行了数值模拟分析,得到不同爆心间距管线的应力峰值.将模拟计算结果和理论计算结果进行了对比分析,结果表明:模拟计算值与TM5-855-1手册理论计算值比较吻合,表明采用数值模拟方法分析爆炸地冲击对埋地管线的作用是可行的,计算结果对地下爆破的安全施工和埋地管线的安全运行具有参考价值. 相似文献
134.
By running life tests at higher stress levels than normal operating conditions, accelerated life testing (ALT) quickly yields information on the lifetime distribution of a test unit. The lifetime at the design stress is then estimated through extrapolation using a regression model. In constant‐stress testing, a unit is tested at a fixed stress level until failure or the termination time point of test, whereas step‐stress testing allows the experimenter to gradually increase the stress levels at some prefixed time points during the test. In this work, the optimal k‐level constant‐stress and step‐stress ALTs are compared for the exponential failure data under complete sampling and Type‐I censoring. The objective is to quantify the advantage of using the step‐stress testing relative to the constant‐stress one. Assuming a log‐linear life–stress relationship with the cumulative exposure model for the effect of changing stress in step‐stress testing, the optimal design points are determined under C/D/A‐optimality criteria. The efficiency of step‐stress testing to constant‐stress one is then discussed in terms of the ratio of optimal objective functions based on the information matrix. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 00: 000–000, 2013 相似文献
135.
董忠厚 《兵团教育学院学报》2013,(3):65-67,78
"兵团音乐"这一语辞包含区域、主题、风格、功能、情感等多重属性。本论文尝试从兵团音乐的特质、兵团音乐创作机制的类型、兵团音乐创作主题的类型三方面来阐释兵团音乐的思想教育功能。 相似文献
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《防务技术》2022,18(11):1935-1944
This paper studies electromagnetoelastic static investigation of a sandwich doubly curved microshell subjected to multi-field loading based on a new thickness stretching included refined higher order shear/normal deformable model. Modified-couple-stress-theory (MCST) is used for accounting small-scale-dependency. The numerical results are derived using an analytical method. The effect of small scale parameter in micro scale, initial electric and magnetic potentials and foundation parameters is studied on the electromagnetoelastic bending results. It is confirmed an enhancing in stiffness of small scale shell with an increase in micro length scale parameter. 相似文献
138.
针对外覆功能梯度涂层的圆柱形复合材料在轴向剪切作用下的界面开裂问题,建立了断裂力学分析的理论模型。运用分离变量和无穷级数法,推导了奇异积分方程;利用Lobatto-Chebyshev配点法将其离散为代数方程组,最后得到了应力强度因子的数值解。对数值结果的讨论表明:在涂层外表面固定的条件下,可以通过降低涂层厚度和设计内侧软而外侧硬的涂层2种途径来有效地减小界面的断裂驱动力。研究结果可为工程中该类复合材料的防断裂优化设计提供理论参考。 相似文献
139.
通过分析悬浮式深弹发射后在空中的弹道特性,建立了深弹弹着点坐标的计算模型。采取蒙特卡洛方法,分别对舰艇六自由度状态下,单管和六联装火箭深弹的弹着点坐标进行了仿真计算,对弹着点的分布规律进行了研究,并得出弹着点的联合密度函数。结果表明,在发射参数存在正态扰动时,弹着点散布区域均呈椭圆形分布,弹着点坐标均仍服从正态分布。 相似文献
140.