未来士兵系统作战概念研究

随着侦察手段、武器平台、打击能力和打击方式等的不断发展,以及军民融合思想的不断深入,从大规模正面火力冲突到现代信息网络下的远程打击,军事作战格局正在不断地发生变化。研究未来士兵系统及其作战概念对于打破固有格局、提升作战效能、融入我军网络信息体系具有非常重要的军事意义。基于对未来士兵系统作战组织、作战活动的分析,构建了侦察作战、打击以及远程打击的基础指挥体系流程和信息交互内容,为作战概念的深入研究提供一定的参考。     

On gamma estimation via matrix kriging

In financial engineering, sensitivities of derivative prices (also known as the Greeks) are important quantities in risk management, and stochastic gradient estimation methods are used to estimate them given the market parameters. In practice, the surface (function) of the Greeks with respect to the underlying parameters is much more desired, because it can be used in real‐time risk management. In this paper, we consider derivatives with multiple underlying assets, and propose three stochastic kriging‐based methods, the element‐by‐element, the importance mapping, and the Cholesky decomposition, to fit the surface of the gamma matrix that can fulfill the time constraint and the precision requirement in real‐time risk management. Numerical experiments are provided to illustrate the effectiveness of the proposed methods.     

水平集方法中速度停止项函数的改进

对速度停止项函数的研究发现,现今的速度停止项采用的单一全局阈值法很难使经典水平集算法得到较准确的分割效果。为此,提出了一种新的速度停止项函数,该函数通过引入变阈值较好的区分了图像的边缘区与同质区,以使采用该速度停止项函数的水平集方程实现在同质区加速演化,在边缘区停止演化的目的。实验结果表明,采用速度停止项函数能够使水平集方法获取更好的分割结果。     

地基C~4I系统的高空核爆电磁脉冲易损性分析

建立了C4I系统的毁伤等级,完成了毁伤机理与毁伤模式分析,运用毁伤树分析方法构建毁伤树模型,确定了C4I系统的致命性部件,对进一步开展新型号导弹武器系统系统易损性评估研究具有一定的参考应用价值。     

C~4ISR系统开发的仿真支持过程分析与建模

C4ISR(Command、Control、Communication、Computer、Intelligence、Surveillance and Reconnaissance)系统开发的仿真活动贯穿于系统全生命周期的各个阶段,仿真支持过程联系着C4ISR系统开发仿真的各类要素。首先对C4ISR系统开发仿真支持的内容进行分析,从生命周期维、仿真产品维和仿真任务维三个维度描述仿真支持内容之间的联系。然后分析了C4ISR系统开发仿真支持过程的层次性,应用UML描述了支持过程中的仿真项目模型和仿真过程模型。在此基础上,应用基于Petri网的工作流网,对C4ISR系统开发的仿真支持过程进行建模,分析了支持过程中活动、产品、角色、约束四类要素的Petri网表示方式。最后在一个C4ISR系统开发仿真支持实例中应用以上分析和建模方法,验证了方法的可行性和应用效果。     

分布式虚拟战场地形实时渲染策略

大规模地形作为分布式虚拟战场的重要组成部分,在非常有限的资源下,很难达到实时性绘制。针对此问题,设计了两级三层的概要四叉树组织地形数据,用多线程模式算法调度数据,以提高庞大地形数据的交互速率;提出基于衔接索引模板的算法来消除裂缝,实现不同细节层次的无缝拼接;引入样本纹理堆栈的纹理合成算子,增强各层次细节地貌的逼真表现。实验表明:该方法能够很好地实现战场环境下地形的实时性绘制,提供稳定的视觉漫游效果。     

金属带式无级变速汽车的性能仿真研究

介绍了金属带式无级变速装置的结构特点和工作原理,建立了带式无级变速汽车的仿真模 型。利用该模型可以模拟各种工况下无级变速汽车的动态特性,评价无级变速汽车的驱动性能、燃油经 济性和排放特性等,最后给出了几种典型道路循环工况下的仿真结果。     

Estimating the probability that a simulated system will be the best

Consider a stochastic simulation experiment consisting of v independent vector replications consisting of an observation from each of k independent systems. Typical system comparisons are based on mean (long‐run) performance. However, the probability that a system will actually be the best is sometimes more relevant, and can provide a very different perspective than the systems' means. Empirically, we select one system as the best performer (i.e., it wins) on each replication. Each system has an unknown constant probability of winning on any replication and the numbers of wins for the individual systems follow a multinomial distribution. Procedures exist for selecting the system with the largest probability of being the best. This paper addresses the companion problem of estimating the probability that each system will be the best. The maximum likelihood estimators (MLEs) of the multinomial cell probabilities for a set of v vector replications across k systems are well known. We use these same v vector replications to form v^k unique vectors (termed pseudo‐replications) that contain one observation from each system and develop estimators based on AVC (All Vector Comparisons). In other words, we compare every observation from each system with every combination of observations from the remaining systems and note the best performer in each pseudo‐replication. AVC provides lower variance estimators of the probability that each system will be the best than the MLEs. We also derive confidence intervals for the AVC point estimators, present a portion of an extensive empirical evaluation and provide a realistic example. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 341–358, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10019     

Analysis of a finite‐buffer bulk‐service queue with discrete‐Markovian arrival process: D‐MAP/Ga,b/1/N

Discrete‐time queues with D‐MAP arrival process are more useful in modeling and performance analysis of telecommunication networks based on the ATM environment. This paper analyzes a finite‐buffer discrete‐time queue with general bulk‐service rule, wherein the arrival process is D‐MAP and service times are arbitrarily and independently distributed. The distributions of buffer contents at various epochs (departure, random, and prearrival) have been obtained using imbedded Markov chain and supplementary variable methods. Finally, some performance measures such as loss probability and average delay are discussed. Numerical results are also presented in some cases. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 345–363, 2003.     

无线电引信扫频波辐照效应及作用机理研究

介绍无线电引信扫频波辐照试验系统,在引信本振频率外较宽范围内,对某型引信进行扫频波辐照试验,结果表明：扫频波辐照能使无线电引信误炸,扫频频段不同,误炸干扰阈值不同;扫频步长、频点驻留时间与引信误炸密切相关,但不会影响引信误炸干扰阈值。其作用机理是：扫频波辐照导致引信自差机振荡状态跃变,引信高频电路输出方波脉冲串,推动执行级误动作使引信误炸。