Relative performance of novel blast wave mitigation system to conventional system based on mitigation percent criteria

Recent researches focused on developing robust blast load mitigation systems due to the threats of terrorist attacks. One of the main embraced strategies is the structural systems that use mitigation techniques. They are developed from a combination of structural elements and described herein as conventional systems. Among the promising techniques is that redirect the waves propagation through hollow tubes. The blast wave propagation through tubes provides an efficient system since it combines many blast wave phenomena, such as reflection, diffraction, and interaction. In this research, a novel blast load mitigation system, employed as a protection fence, is developed using a technique similar to the technique of the bent tube in manipulating the shock-wave. The relative performance of the novel system to the conventional system is evaluated based on mitigation percent criteria. Performances of both systems are calculated through numerical simulation. The proposed novel system proved to satisfy high performance in mitigating the generated blast waves from charges weight up to 500 kg TNT at relatively small standoff distances (5 m and 8 m). It mitigates at least 94％ of the blast waves, which means that only 6％ of that blast impulse is considered as the applied load on the targeted structure.     

基于评价指标模糊集的复杂系统效能评估方法研究*

提出了一种基于评价指标模糊集的复杂系统效能评估方法。该方法利用系统评价指标的模糊性构造模糊集,以模糊集贴近度来定义评价指标的模糊隶属度函数,结合模糊层次分析法,提出了一种适用于复杂系统功能与多层评估指标体系的效能评估新方法。仿真应用的结果表明:该方法行之有效,具有较好的实用前景。     

灰色层次分析法战术通信网抗干扰效能评估

构建了战术通信网抗干扰效能评估指标体系,运用灰色层次分析法和群组决策特征根算法对抗干扰效能进行了评估。评估结果表明,该抗干扰效能一般,需要采取相关抗干扰对策以提高其抗干扰能力。     

基于可拓方法的C3I作战方案生成与评价

作战指挥决策支持系统是指挥自动化系统的重要组成部分,作战方案生成与评价是作战指挥决策支持系统的基本功能.根据作战指挥决策支持系统特点将可拓方法应用于作战方案生成与评价,并分析了其优势所在.结合空战案例运用发散树方法进行作战方案集的开拓,并利用优度评价方法进行作战方案的评价,从而得到最佳作战方案.     

对防空部队自动化控制系统的电子压制(二)效能指标

电子压制是赢得现代战争的关键技术。首先分析电子压制的应用背景,建立地面防空系统的分析模型并给出攻击机突破地面防空系统过程中,电子压制对方自动化控制系统的效能评估指标。给出的模型和效能评估指标可对作战决策提供理论依据。     

基于中间表示规则替换的二进制翻译中间代码优化方法

动态二进制翻译在实现多源到多目标的程序翻译过程中,为屏蔽不同源平台间的硬件差异引入中间代码,采用内存虚拟策略进行实现,但同时带来中间代码膨胀问题。传统的中间代码优化方法主要采用对冗余指令进行匹配删除的方法。将优化重点聚焦在针对特殊指令匹配的中间表示规则替换上,提出了一种基于中间表示规则替换的二进制翻译中间代码优化方法。该方法针对中间代码膨胀所呈现的几种典型情景,描述了中间表示替换规则,并将以往应用在后端代码优化上的寄存器直接映射策略应用在此处。通过建立映射公式,实现了将原来的内存虚拟操作替换为本地寄存器操作,从而降低了中间代码膨胀率。使用SPEC CPU2006测试集进行了实验,验证了此优化方法的正确性和有效性。测试用例在优化前和优化后的执行结果一致,验证了优化方法的正确性;优化后测试用例的中间代码平均缩减率达到32.59%,验证了优化方法的有效性。     

A comparative study of three tool replacement/operation sequencing strategies in a flexible manufacturing system

This paper studies three tool replacement/operation sequencing strategies for a flexible manufacturing system over a finite time horizon: (1) failure replacement—replace the tool only upon failure, (2) optimal preventive tool replacement for a fixed sequence of operations, and (3) joint scheduling of the optimal preventive tool replacement times and the optimal sequence of operations. Stochastic dynamic decision models are used for strategies 2 and 3. The optimization criterion for strategies 2 and 3 is the minimization of the total expected cost over the finite time horizon. We will show through numerical studies that, with the same amount of information, the total expected costs can be reduced considerably by choosing an optimal strategy. Our conclusion is that in flexible manufacturing, optimal tool replacement and optimal operations sequencing are not separate issues. They should be considered jointly to minimize the expected total cost. © 2000 John Wiley & Sons, Inc. Naval Research Logistics 47: 479–499, 2000     

基于串联模型框架的目标威胁评估

针对防空武器系统防空作战特点,在对目标威胁程度影响因素分析的基础之上,运用模糊理论和多模型理论探索目标威胁评估问题。设计了一种基于串联模型框架的目标威胁评估方法,该方法采用3个基本模型,基于串联系统思想,经模糊推理融合,得到空中来袭目标的威胁程度。该评估方法层次分明、直观有效,能够较好地满足海上对空防御作战中对目标威胁评估的需要,为舰指挥员决策和防空武器系统火力分配提供一定的依据。     

运用模糊数学方法综合评价教学质量

提高教学质量是所有学校不断追求和努力的方向。由于在进行教学质量的评价中，不但要根据教学目标和标准选取指标体系，而且对每一指标的评价又存在一定的模糊性。将模糊数学方法运用到教学质量的评价中，先建立模糊数学模型，然后进行实例研究，既得到了定性评价结果，也得到了定量评价结果，为教学管理部门提供科学、合理的评价方法。     

基于生存能力的作战方案评估仿真模型

导弹武器系统的生存能力是反映作战方案好坏的定量依据之一。给出了基于生存能力的导弹作战方案评估系统的模型体系和构成,通过对该系统评估模型中的指标分析,建立了伪装生存能力、防护生存能力、机动生存能力等多个模型,并将其综合为对作战方案的生存能力评估模型。经过一定的仿真试验证明,模型正确,运行结果符合实际。