一种飞机对地突击效能的分析方法

对地突击是空军航空兵的重要作战样式.计算和判断我机各种作战效能是指挥员规划突击兵力、确定弹药储运和判断战损抢修需求的重要的依据.从单架次飞机突击敌固定目标的行动特点分析入手,建立了一组反映突击行动效果的数学模型,并通过具体算例给出模拟结果.该方法简单、实用,可为指挥员规划突击兵力提供定量分析参考.     

面向仿真试验床的空地突击指令生成系统框架

基于仿真试验床研究武器装备效能是一种非常有效的方式,然而在其想定编写过程中,空中指令需要由操作人员逐条下达,输入效率低且达不到优化使用作战资源的效果,因此,研究面向仿真试验床的空地突击指令生成系统有着重要的现实意义。文章首先对有关概念进行解析,然后根据空地突击作战力量组成和作战流程分析,提出了一种面向仿真试验床的空地突击指令生成系统框架,为实现空地突击指令的计算机辅助生成奠定了基础。     

63A坦克进攻作战中最优突击效果仿真模型

对63A坦克进攻突击作战过程中,敌方目标设置的重要性、危害性、针对性等不同而造成的我方突击效果差异,引入动态规划方法,就如何做好我方坦克多阶段决策优化分配问题作了探讨.     

美军的空中突击作战方式

美军的空中突击作战,不但十分依赖高技术空袭兵器,而且也十分重视突击方式的研究与运用。从近期几场局部战争来看,美军空中突击作战方式主要有以下几种: 合成突击合成突击,就是将隶属于不同军(兵)种的不同型号、不同功能的空袭兵器,在统一指挥下合理编组,形成功能齐全的空中作战系统,以整体力量协调一致地完成空袭作战任务。这是美军空中突击作战的基本突击方式。     

一种航线规划算法应用

主要探讨在舰载机的反舰突击作战中,如何利用A*(读做A Star)算法在航线规划中进行最优航线选择。在想定条件下,利用A*算法为红方的突击群兵力规划一条威胁最小的突击航线,并在假设数据条件下,通过Matlab对算法的实现,给出相应的突击航线。     

地面突击装备武器系统发展趋势与关键技术分析

针对地面突击装备在陆上突击作战中的作用,从武器系统架构、目标探测、武器控制、火力打击4个方面研究了地面突击装备武器系统国外发展现状和发展趋势,针对地面突击装备武器系统需要重点研究的开放式体系架构技术、全天候立体化态势感知技术、高精度智能化武器综合控制管理技术和多样化火力打击集成技术进行了分析,提出了解决技术途径,对于地面突击装备武器系统发展的具有一定借鉴作用。     

正确把握抓任务与打基础的辩证关系

着眼于我军在高技术战争和市场经济条件下“打得赢”、“不变质”的两大历史性使命 ,继续推动部队基层建设向更高层次迈进 ,必须在总结经验的基础上 ,充分认识和正确处理好抓任务与打基础的关系 ,努力促进部队基层建设的协调发展。一、坚持把突击抓任务与经常打基础有机结合起来 ,在促进部队稳步发展上求突破。突击抓任务 ,是部队建设时效性的客观要求。但是 ,基层建设是一个循序渐进的过程 ,有些工作可以靠突击完成 ,有些工作就不能靠突击去抓 ,即使突击抓任务取得的成果也需要经常性的工作来巩固和发展。这就要求我们必须把“突击抓”建立…     

苏军抗击德军反突击的经验及对今后作战的一些新看法

第二次世界大战中,在苏军转入战略进攻之后,德军为了阻止苏军的进攻,在实行防御和退却时,曾对苏军进行了一系列的反突击。苏军为了保障不间断地发展进攻,对德军的反突击实施了有力的抗击,并取得了一些成功的经验。一、抓住进攻战役的关键,组织好各阶段的抗击反突击苏军认为,在进攻战役中,防御的军队必然会采取反突击的手段阻止进攻的军队。如果抗击反突击不能成功,进攻战役的任务就难以完成。因此,组织好各阶段的抗击反突击,     

机动岸导突击群作战效能评估模型研究

针对机动岸导突击群作战效能量化评估较为困难的问题,运用系统学的观点阐释了机动岸导突击群作战效能涌现性的概念,给出了其涌现性的判定准则.在分析机动岸导火力单元作战效能指标基础上,充分考虑机动岸导突击群作战体系的涌现行为,设计了突击群作战效能涌现性指标体系,提供了各项评价指标的数学模型,从而为机动岸导突击群作战效能的定量评...     

基于SA的常规导弹火力突击作战区选择问题

常规导弹部队执行火力突击任务时，需要选择对当前任务适应度较好的作战区，使导弹能在规定的时间内占领各发射阵地，对敌火力突击效能最大的目的。导弹执行突击任务时要充分考虑多个问题：如突击任务时间节点要求，实际作战区配置，实际兵力部署情况，导弹技术性能等诸多因素。在执行突击任务准备进入作战区时又受道路交通条件、阵地隐蔽性、任务...     

Terrorism,crime and public spending: Panel VAR evidence from europe

Within a panel VAR framework and utilizing generalized impulse response and forecast error variance decomposition analysis, we explore the dynamic effects of terrorism and crime on public order and safety spending across European countries during the period 1994–2006. Our findings show that a ‘shock’ in terrorism and/or in crime, significantly increases the subsequent trajectory of public order and safety spending. As a by-product, we find that public spending is ineffective in reducing observed crime or terrorism.     

Assessing the value of demand sharing in supply chains

We consider the problem of assessing the value of demand sharing in a multistage supply chain in which the retailer observes stationary autoregressive moving average demand with Gaussian white noise (shocks). Similar to previous research, we assume each supply chain player constructs its best linear forecast of the leadtime demand and uses it to determine the order quantity via a periodic review myopic order‐up‐to policy. We demonstrate how a typical supply chain player can determine the extent of its available information in the presence of demand sharing by studying the properties of the moving average polynomials of adjacent supply chain players. The retailer's demand is driven by the random shocks appearing in the autoregressive moving average representation for its demand. Under the assumptions we will make in this article, to the retailer, knowing the shock information is equivalent to knowing the demand process (assuming that the model parameters are also known). Thus (in the event of sharing) the retailer's demand sequence and shock sequence would contain the same information to the retailer's supplier. We will show that, once we consider the dynamics of demand propagation further up the chain, it may be that a player's demand and shock sequences will contain different levels of information for an upstream player. Hence, we study how a player can determine its available information under demand sharing, and use this information to forecast leadtime demand. We characterize the value of demand sharing for a typical supply chain player. Furthermore, we show conditions under which (i) it is equivalent to no sharing, (ii) it is equivalent to full information shock sharing, and (iii) it is intermediate in value to the two previously described arrangements. Although it follows from existing literature that demand sharing is equivalent to full information shock sharing between a retailer and supplier, we demonstrate and characterize when this result does not generalize to upstream supply chain players. We then show that demand propagates through a supply chain where any player may share nothing, its demand, or its full information shocks (FIS) with an adjacent upstream player as quasi‐ARMA in—quasi‐ARMA out. We also provide a convenient form for the propagation of demand in a supply chain that will lend itself to future research applications. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 515–531, 2014     

高压下激波波阵面温升的计算

针对高压气体管路中的激波现象,建立了激波波阵面温升的计算模型,模型中考虑了高压气体中声速的变化对激波波阵面温升的影响．     

圆柱壳体内 X 射线热击波的二维力学计算

依据二维流体弹塑性模型及二维断裂处理方法,研究Ｘ射线热击波在圆柱壳体内的传播规律。计算结果揭示了圆柱壳体内热击波的一些二维效应。     

基于镜像延拓和神经网络的EMD端点效应改进方法

经验模态分解(Empirical Mode Decomposition,EMD)在机械故障诊断中存在一个比较严重的问题,即端点效应。镜像延拓是克服端点效应的有效方法,采用镜像延拓处理端点效应时,要求将镜面放置在局部极值点处,针对这一问题,提出了一种基于镜像延拓和神经网络相结合的数据延拓方法。采用神经网络预测原信号序列,将信号向前向后各延拓一个极值点,再采用镜像延拓有效地减小EMD分解中的端点效应。通过对仿真信号的分析,验证了该方法能有效抑制EMD方法中的端点效应问题。     

Mitigation effects on the reflected overpressure of blast shock with water surrounding an explosive in a confined space

The mitigation of blast shock with water has broad application prospects. Understanding the mitigation effects on the reflected overpressure of the explosion shock with water surrounding an explosive in a confined space is of great significance for military explosives safety applications. To estimate the effects of the parameters on the reflected overpressure of blasted shock wave, a series of experiments were carried out in confined containers with spherical explosives immersed in a certain thickness of water, and numerical simulations were conducted to explore the corresponding mechanisms. The results reveal that the reflected overpressure is abnormally aggravated at a small scaled distance. This aggravation is due to the high impulse of the bulk accelerated water shell converted from the explosion. With increasing scaled distance, the energy will be gradually dissipated. The mitigation effects will appear with the dispersed water phase front impacting at a larger scaled distance, except in the case of a dense water phase state. A critical scaled distance range of 0.7—0.8 m/kg1/3 for effective mitigation was found. It is suggested that the scaled distance of space walls should be larger than the critical value for a certain water-to-explosive weight ratio range (5—20).     

To wait or not to wait: Optimal ordering under lead time uncertainty and forecast updating

There has been a dramatic increase over the past decade in the number of firms that source finished product from overseas. Although this has reduced procurement costs, it has increased supply risk; procurement lead times are longer and are often unreliable. In deciding when and how much to order, firms must consider the lead time risk and the demand risk, i.e., the accuracy of their demand forecast. To improve the accuracy of its demand forecast, a firm may update its forecast as the selling season approaches. In this article we consider both forecast updating and lead time uncertainty. We characterize the firm's optimal procurement policy, and we prove that, with multiplicative forecast revisions, the firm's optimal procurement time is independent of the demand forecast evolution but that the optimal procurement quantity is not. This leads to a number of important managerial insights into the firm's planning process. We show that the firm becomes less sensitive to lead time variability as the forecast updating process becomes more efficient. Interestingly, a forecast‐updating firm might procure earlier than a firm with no forecast updating. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009     

节流方式对隔离段流场结构影响的数值仿真

在隔离段尾部设计节流装置是试验上模拟反压对隔离段流场影响的常用方法。针对不同节流方式对隔离段流场结构的影响,采用数值模拟方法进行了比较研究。比较三种节流方式,包括在斜坡面尾部设置节流直板、在头罩面尾部设置节流直板和流场中间布置对称斜楔等。结果表明,由于隔离段斜坡面和头罩面边界层发展的非对称性,三种方式所产生的激波串结构均靠近头罩一侧的壁面。第二种方式产生的激波串强度较大,边界层分离较为严重,容易造成流场堵塞,在实际中不利于激波串的试验研究。另外两种方式所产生的流场结构类似,但是第一种方式在设计加工上相对容易实现。     

基于FMECA的某型雷达系统故障分析

故障模式、影响及危害性分析 (简称FMECA)是提高系统可靠性的一种有效的工具。在雷达系统故障分析中运用FMECA方法 ,通过计算机辅助程序实现了故障分析的预测分析和定量分析。与传统的故障分析方法相比 ,该方法能够避免分析中的盲目性和主观性 ,可以获得更为准确的分析结果     

设备级电磁脉冲效应仿真算法研究综述

综述了国内外现有主要电磁脉冲效应仿真方法，认为普遍存在的问题是计算过程复杂、理论与实践脱节，提出将系统辨识和神经网络等技术应用于电子设备电磁脉冲效应仿真研究，探索基于实验数据统计的设备级电磁脉冲能量耦合建模与敏感度预测新方法是该领域的发展方向。