气体自发光在高超声速流场显示中的应用

提出了利用高焓气体自发光作为高超声速流场显示的方法，介绍了在使用高焓运行的激波风洞中，对二维模型的高超声速绕流流场使用此种方法的初步结果，可观察到二维棱形柱的尾流和马赫波的相交。结果表明此种方法不需外加光源，对于结构限制无法设置透明部件的模型，无疑是简单可行的。     

基于PSO算法的半球谐振陀螺惯导系统陀螺温度补偿方法

针对半球谐振陀螺受温度影响出现零位漂移的问题，以测温电路温度为基准，建立温度频率函数实时解算温度，提出一种基于粒子群优化(PSO)算法的半球谐振陀螺惯导系统陀螺温度补偿方法。在求解温度时，需要先将温度频率函数转换为一元三次方程，存在测试计算量大的问题。引入逆向拟合思想，建立频率温度函数，提高陀螺输出温度实时性和降低测试计算量，替代了传统陀螺测温硬件电路，为惯导系统轻小型设计提供新思路。考虑温度变化、温度变化率以及两者的交叉项，建立温度补偿模型，引入PSO算法求解模型系数。温度试验结果表明，在温箱温度为-40~50 ℃内，补偿后的半球谐振陀螺的零偏稳定性较补偿前提升了46％。     

一种便携式多通道精密测温仪

介绍了利用数字式温度传感器 DS1 6 2 4构成的多路温度测量仪器。它具有线路简单 ,测量精度高的优点 (在 - 5 5～ 1 2 5°C内 ,精度优于 0 .0 5°C) ;带有计算机接口 ,能够实现长时间连续测量。     

风场中基于神经网络的炸弹弹道落点拟合分析

介绍了两种炸弹弹道落点拟合神经网络模型,对各模型的优缺点以及处理结果进行了分析。提出了采用广义回归神经网络来处理炸弹弹道落点拟合问题,弹道的落点参数、初始投放条件与风场可通过神经网络的阈值和权值来表现。仿真结果表明,应用广义回归神经网络进行弹道落点拟合,具有算法可行性好、拟合精度高、速度快等优点,而且运算简单;该方法在实战中有很高的参考价值和工程实用价值。     

Physical mechanism of the vertical electric field generation over active tectonic faults

The concept of the Global Electric Circuit (GEC) provides an explanation of the existence of a vertical atmospheric electric field and coupling between the ground and ionosphere. Presently, ionospheric physics pays more attention to electric fields and coupling processes in the polar and auroral regions, whereas in other areas the potential difference between the ground and ionosphere usually is not taken into account. Regional processes exist, however, that are able to significantly affect the GEC parameters and through modification of the ionospheric potential to create plasma density irregularities of different scales within the ionosphere. One such source of ionosphere modification is air ionization in the vicinity of active tectonic faults, which takes place due to increased radon emanation. This paper considers the process of local modification of the GEC and corresponding ionospheric variability due to tectonic activity.     

The Origin of Mercury’s Internal Magnetic Field

Mariner 10 measurements proved the existence of a large-scale internal magnetic field on Mercury. The observed field amplitude, however, is too weak to be compatible with typical convective planetary dynamos. The Lorentz force based on an extrapolation of Mariner 10 data to the dynamo region is 10⁻⁴ times smaller than the Coriolis force. This is at odds with the idea that planetary dynamos are thought to work in the so-called magnetostrophic regime, where Coriolis force and Lorentz force should be of comparable magnitude. Recent convective dynamo simulations reviewed here seem to resolve this caveat. We show that the available convective power indeed suffices to drive a magnetostrophic dynamo even when the heat flow though Mercury’s core–mantle boundary is subadiabatic, as suggested by thermal evolution models. Two possible causes are analyzed that could explain why the observations do not reflect a stronger internal field. First, toroidal magnetic fields can be strong but are confined to the conductive core, and second, the observations do not resolve potentially strong small-scale contributions. We review different dynamo simulations that promote either or both effects by (1) strongly driving convection, (2) assuming a particularly small inner core, or (3) assuming a very large inner core. These models still fall somewhat short of explaining the low amplitude of Mariner 10 observations, but the incorporation of an additional effect helps to reach this goal: The subadiabatic heat flow through Mercury’s core–mantle boundary may cause the outer part of the core to be stably stratified, which would largely exclude convective motions in this region. The magnetic field, which is small scale, strong, and very time dependent in the lower convective part of the core, must diffuse through the stagnant layer. Here, the electromagnetic skin effect filters out the more rapidly varying high-order contributions and mainly leaves behind the weaker and slower varying dipole and quadrupole components (Christensen in Nature 444:1056–1058, 2006). Messenger and BepiColombo data will allow us to discriminate between the various models in terms of the magnetic fields spatial structure, its degree of axisymmetry, and its secular variation.     

FPGA在超周期延时电路中的应用

一般电路的暂态输出时间相对不是很长 ,而且电路的输入触发信号时间应小于输出时间的长度 ,这种电路设计思想有时满足不了某些场合的实际工程需要。为此 ,本文结合工程实际需要给出了利用FPGA设计超周期延时功能模块 ,该模块能准确的进行时序控制 ,可以不修改硬件满足时序要求。     

叉流管－管型换热器二维温度场的数值分析

建立并导出叉流管－管型换热器传热过程的二维数学模型及相应的差分格式。对比实验数据和性能计算结果，表明数值方法是有效可行的，据此编制的计算机程序已成功地用于组合发动机空气预冷换热器工作过程的预测。     

一种新型恒温—温补晶体振荡器

提出了一种ＯＣＸＯ的恒温控制方法。该方法是利用乙醇的沸点制成换态式恒温箱。这种温度控制方法既可以用作中准确度的ＯＣＸＯ，又可以作为精密双层控温ＯＣＸＯ的外层恒温装置，还可以与简单的温补线路结合，构成高准确度的ＯＴＣＸＯ。     

实用换能器频谱及声场特性分析

本文从超声检测原理出发 ,针对超声检测中近场区内缺陷难以准确定量的问题 ,利用计算机数字信号处理技术 ,通过对不同换能器进行频谱分析 ,计算各换能器声轴线上声压分布曲线 ,并进行对比实验 ,探讨了超声检测中声轴线上声压分布的一般规律。为提高超声检测的可靠性 ,并最终解决上述问题提供了理论和实验依据