VV&A在红外目标模拟器中的应用及其逼真度评估

将校核、验证与确认(VV&A)技术应用于红外目标模拟器系统,并对红外目标模拟器的VV&A工作模式进行了研究.然后依据点源目标模拟器建立了指标体系,并对该模拟系统进行了逼真度评估.计算结果表明,该方法具有可行性,可以灵活运用逼真度定义,从而间接地对系统的可信度进行评估.     

半实物仿真中红外场景的模拟可信度评估

提出一种利用模拟目的校核和逼真度验证来评估半实物仿真中红外场景模拟可信度的方法。在探讨模拟目的、逼真度以及"相对等效"原理的基础上,提出特殊的群运算,有效进行了红外场景的模拟目的校核,定性地反映了模拟红外场景达到半实物仿真任务对应模拟目的的能力。将正态分布的思想应用到由偏差度到逼真度的转化过程中,设计算法分别实现了仿真起始点等效逼真度和仿真变化过程逼真度的验证。最后,给出了模拟起始时刻逼真度和变化过程逼真度的权重比较方法,进行了综合逼真度验证,从而定量地评估了模拟红外场景再现实战红外场景的准确程度。     

红外目标模拟逼真度的评估方案设计

提出了一种研究半实物仿真中红外目标模拟逼真度的评估方案。红外目标模拟的逼真是整个过程的逼真,将其等价为起始时刻模拟逼真和变化过程模拟逼真的结合。首先对实战场景进行了设置和计算,并分析了逼真度评估指标和评估方法,然后重点研究了起始时刻的等效逼真的评估内容和变化过程逼真的评估内容,最后借助权重计算,将起始时刻等效逼真和变化过程逼真结合起来得到了红外目标模拟的整体逼真度。     

基于跟踪特征的目标模型逼真度评估方法

为了实现红外仿真目标模型逼真度评估的目的，采用了基于跟踪算法提取目标模型关键特征的方法，通过分析跟踪过程的重点，确定以目标为中心的局部视场区域图像来评估目标模型。在现有红外仿真目标模型评估现状的基础上，采用典型的跟踪算法来设计完成试验，并进行了理论分析和试验验证，取得了较好的试验结果。结果表明，基于关键特征提取的方法中相似目标模型是不相似目标模型的2倍以上，有些高达10倍差距，可以基于目标图像关键特征来验证目标模型的有效性。此研究算法为后续红外仿真目标模型逼真度的评估具有实际指导和扩展的意义。     

电磁环境模拟构建与逼真度评估

电磁环境模拟构建与评估是实战化训练中的关键问题。从分析电磁环境构建的基本要求入手,结合训练实际和需求,提出了电磁环境构建的总体方法。针对电磁环境逼真性评估问题,明确了电磁环境逼真度评估概念,给出了评估总体思路,建立了基于IDEF0的电磁环境逼真度评估活动模型,提出了基于相似系统理论的评估方法。     

其它测量

0633242模拟退火算法在基于非稳态驱替实验的相对渗透率计算中的应用[刊,中]／柯式镇／／中国石油大学学报(自然科学版)．-2006,30(4)．-35-37(E) 0633243基于北斗定位技术的试验靶船自动监测系统[刊,中]／王海涛／／指挥控制与仿真．-2006,28(5)．-104-106, 110(L)海上武器飞行试验任务中,靶船位置飘移大小和姿态的变化将直接影响试验进程。针对海上武器试验的特殊性,设计研制了试验靶船自动监测系统。利用北斗卫星定位功能对靶船进行实时定位．利用北斗通信功能传送GPS定位、授时数据和三维姿态测量数据,可以在布靶结束后实时监测靶船的位置和姿态．为试验指挥人员提供真实可靠的指挥决策依据。在试验任务中取得了较好的效果。参5     

靶船电子对抗系统遥控设计

根据海军靶船的实际情况,设计了无线遥控系统来实现靶船电子对抗系统的遥控,分析了靶船电子对抗系统的现状,得出对靶船的电子对抗进行遥控是完全可行的,并给出了靶船电子对抗系统遥控方式的工作流程,设计了靶船电子对抗系统和受控站之间的接口控制。     

激光目标模拟器逼真度量化评估方案

激光目标模拟器逼真度主要用来评估目标模拟器出射激光对实际场景中激光照射器出射激光在传输及被目标发射时的近似程度。逼真度评估的有效程度取决于评估方案的适用性及实际可操作性。因此,提出了一种激光目标模拟器模拟逼真度的有效评估方案,并给出了具体指标的量化逼真度定义。首先给出了实战中的激光能量传输模型和半实物仿真系统中的光斑控制模型,接着以此为依据重点研究了激光目标模拟器激光脉冲和激光光斑特性的逼真度评估内容,最后通过计算各分项指标权重,得出了激光目标模拟器的整体逼真度。逼真度量化评估方案可应用于激光目标模拟器的设计及性能评估,从而达到在室内完成半实物仿真测试以减少总体测试费用和时间的目的,对于现代化武器系统设计具有十分重要的意义。     

基于HLA FEDEP的VV&A过程

仿真的可信度直接制约了仿真的应用,也给仿真应用带来了风险,对仿真可信度的研究是必需的、也是必要的。分析了VV&A的相关概念,指出了基于HLA的VV&A与传统M&S中的VV&A的几点不同,基于HLA FEDEP的七个步骤,将VV&A分为了七个阶段。     

红外景象模拟器的结构模型及其噪声分析

对组成红外景象模拟器的各个子系统进行了深入地分析并详细介绍了各组成部分的功能及其之间的内在联系,给出了各个子系统的数学描述,用来仿真红外景象模拟器来促进算法的发展而提高景象模拟的逼真度.根据其结构特征分析了红外景象模拟器在工作过程中的噪声问题,为红外景象模拟器的评估研究提供了有利的依据.     

Modeling and simulation of emissivity of silicon-related materials and structures

A brief review of the models that have been proposed in the literature to simulate the emissivity of silicon-related materials and structures is presented. The models discussed in this paper include ray tracing, numerical, phenomenological, and semi-quantitative approaches. A semi-empirical model, known as Multi-Rad, based on the matrix method of multilayers is used to evaluate the reflectance, transmittance, and emittance for Si, SiO₂/Si, Si₃N₄/SiO₂/Si/SiO₂/Si₃N₄ (Hotliner), and separation by implantation of oxygen (SIMOX) wafers. The influence of doping concentration and dopant type as well as the effect of the angle of incidence on the radiative properties of silicon is examined. The results of these simulations lead to the following conclusions: (1) at least within the limitations of the Multi-Rad model, near the absorption edge, the radiative properties of Si are not affected significantly by the angle of incidence unless the angle is very steep; (2) at low temperatures, the emissivity of silicon shows complex structure as a function of wavelength; (3) for SiO₂/Si, changes in emissivity are dominated by substrate effects; (4) Hotliner has peak transmittance at 1.25 μm, and its emissivity is almost temperature independent; and (5) SIMOX exhibits significant changes in emissivity in the wavelength range of 1–20 μm.     

海森堡模型中概率及相应熵的计算分析

介绍海森堡模型的不同位型[N,n] （N为海森堡链总格点数, n为格点中自旋向下的电子数）中的体现本征值获取难易程度的本征值获取概率及其相应信息熵（香农所定义的）和体现模型体系关联程度的自旋向下电子发现概率、每一粒子的von Neumann及体系的平均von Neumann熵,可为量子计算与信息传递提供启示性信息。研究结果：(1)事件发生概率大于（小于）50%时,信息熵随概率增加而减小（增加）。(2)不同位型[N,n],当n（N）同, N（n）增加时：本征值获取概率减小,其相应的信息熵正确反映本征值获取的难易程度;模型参数一定时,格点中自旋向下电子发现概率与每一粒子的von Neumann及体系的平均von Neumann熵都分别减小（增加）。(3)位型[N,n]相同时, 每一粒子的von Neumann及体系的平均von Neumann熵随参数变化时出现拐点,显示体系发生量子相变的信息。(4)同位型[N,n]且同参数时处于海森堡链对称位置粒子的von Neumann熵相同。     

Mechanisms and kinetics of vapor-phase etching of GaAs and GaP

Vapor-phase etching of (111), (111), (110) GaAs and (111), (111) GaP wafer in H₂ + HBr or H₂ + PBr₃ gas mixtures has been conducted. The results of two cases, with liquid-forming metal (gold) layers or without coatings, are compared. Etching rates as a function of temperature in the range of 600? to 950? C were measured in Arrhenius coordinates. For both materials and for different gas environments, low-, medium- and high-temperature regions are distinguished, the activation energies in the low-temperature region (below about 650?c) being quite different for the two cases. The kinetic results are correlated with morphological changes arising from temperature variations. Some conclusions are made about the mechanisms of chemical vaporization in various temperature regions. The vaporization mechanisms have much in common with those for A^II - B^VI compounds.     

An Investigation of Microstructure and Microhardness of Sn-Cu and Sn-Ag Solders as Functions of Alloy Composition and Cooling Rate

The microstructure and microhardness of Sn-xAg and Sn-xCu solders were investigated as functions of alloy composition and cooling rate. The Ag compositions examined varied from 0.5 wt.% to 3.5 wt.%, while Cu varied from 0.5 wt.% to 2.0 wt.%. Three cooling rates were employed during solidification: 0.02°C/s (furnace cooling), about 10°C/s (air cooling), and 100°C/s or higher (rapid solidification). Sn grain size and orientation were observed by cross-polarization light microscopy and electron-backscattering diffraction (EBSD) techniques. The microhardness was measured to correlate the mechanical properties with alloy compositions and cooling rates. From this study, it was found that both alloy composition and cooling rate can significantly affect the Sn grain size and hardness in Sn-rich solders. The critical factors that affect the microstructure–property relationships of Sn-rich solders are discussed, including grain size, crystal orientation, dendrite cells, twin boundaries, and intermetallic compounds (IMC).     

Optical and photocatalytic properties of indium phosphide nanoneedles and nanotubes

Large scale indium phosphide (InP) nanoneedles and nanotubes were synthesized through a facile solvothermal reaction. The morphology and microstructure of the samples were analyzed by employing scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, and Ultraviolet-visible (UV–vis) spectroscopy. The room temperature photoluminescence (PL) measurements showed that the InP nanoneedles and nanotubes possessed a pronounced blue shift in contrast to the bulk counterpart, which was ascribed to the crystalline defects effect. Moreover, the InP nanotubes exhibited an enhanced photocatalytic performance as compared to the InP nanoneedles and nanoparticles.     

The effects of PMD and PDL on the performance of OOK and DPSK systems

Using multiple importance sampling （MIS） technique, the optical communication system performance affected by polarization-mode dispersion （PMD） and polarization-dependent loss （PDL） is simulated numerically. The power penalties and system outage probabilities are obtained for optical communication systems with on-off keying （OOK） or differential phase shift keying （DPSK） modulation. The simulation results show that DPSK always performs better than OOK. When the system has moderate PDL （about 1.5 dB）, it is necessary to compensate effectively the fiber PMD in order to enhance the system tolerance to the PMD and PDL. However, the efficiency of PMD compensation will degrade rapidly when the PMD of the whole optical link drops into the low value.     

超宽带脉冲波形的收发特性分析

采用时域电场积分方程和互易原理相结合的方法,探讨了已知接收信号的情况下,脉冲发送信号的波形,并研究了视距和非视距两种传播路径对脉冲收发信号的影响.在分析中,脉冲波形和天线几何形状可以任意.分别以蝴蝶形天线和超宽带槽式天线为例,并将计算结果与已知接收脉冲信号进行了比较.它们之间良好的一致性说明了所提方法的正确性和有效性.     

Capability and Limitations of Electrocardiography and Magnetocardiography

The capabilities and limitations of electrocardiography and magnetocardiography are discussed. Representing the electrical activity of the heart by an impressed current density ji, electrocardiography determines the spherical harmonic multipole expansion of its divergence (flux source), while magnetocardiography determines the spherical harmonic multipole expansion of the radial component of its curl (vortex source).     

超宽带定位研究与应用:回顾和展望

 超宽带(Ultra-Wideband,UWB)技术能获得比现有无线定位技术更高的测距定位精度.本文主要讨论UWB定位技术的研究和应用,包括TOA/TDOA(Time/Time Difference of Arrival)等UWB定位方法、多径时延估计理论、非视距定位和协作式定位、多带OFDM(Orthogonal Frequency Division Multiplexing)定位和其他超宽带信号定位方式等方面,对其发展历程和现状进行了充分的叙述和分析,最后指出了仍存在的问题和值得进一步探讨的方向.     

矿区专用铁路调度监督系统的研制

介绍一种矿区专用铁路调度监督系统.该系统以AT89C系列单片机作为中央处理芯片,通过普通双绞电话线和调制解调芯片等实现了上千路开关量信号的实时采集、远距离接力式传输和调度中心大屏幕模拟车站现场显示.实际运行结果表明该系统工作稳定,实时性较好,给铁路调度指挥工作带来很大的方便.