EWB应用于模拟电路分析的研究

介绍了将EWB用于“模拟电子技术”的课堂教学时，虚拟实验测量结果与理论计算值不一致时，如何去分析并解决问题。     

两个非线性方程的准确解

借助于计算机代数系统Ｍａｔｈｅｍａｔｉｃａ利用直接代数方法获得了两个有数学物理意义的非线性耗散－色散方程的准确解，这种方法也适用于高维非线性方程。     

Velocity spectrum for non-Markovian Brownian motion in a periodic potential

Non-Markovian Brownian motion in a periodic potential is studied by means of an electronic analogue simulator. Velocity spectra, the Fourier transforms of velocity autocorrelation functions, are obtained for three types of random force, that is, a white noise, an Ornstein—Uhlenbeck process, and a quasimonochromatic noise. The analogue results are in good agreement both with theoretical ones calculated with the use of a matrix-continued-fraction method, and with the results of digital simulations. An unexpected extra peak in the velocity spectrum is observed for Ornstein-Uhlenbeck noise with large correlation time. The peak is attributed to a slow oscillatory motion of the Brownian particle as it moves back and forth over several lattice spaces. Its relationship to an approximate Langevin equation is discussed.     

Application of the finite Hankel transform to a diffusion problem without azimuthal symmetry

The problem treated in this paper concerns calculating the evolution of the pressure in a single-phase, slightly compressible fluid in a porous medium consisting of communicating layers. The fluid is produced through a point sink located on the side of an otherwise sealed cylindrical wellbore. This location of the sink causes the flow around the wellbore to be azimuthally asymmetric.The problem is solved through successive application of Laplace, finite Fourier and finite Hankel transforms. Although apparently straightforward, this approach leads to serious numerical difficulties. The published form of the inversion formula for the finite Hankel transform leads to inaccurate computation for the higher azimuthal modes even with 128 bit arithmetic. An alternative form is developed which enables accurate evaluation of the solution with the more practical 64 bit arithmetic. The technique for two-layer solution presented here can be directly extended to a problem with a larger number of communicating layers. This is the first instance of successful application of the finite Hankel transform to an azimuthally asymmetric diffusion problem.     

激光干涉环圆心位置测定技术及应用

本文利用在平面内绕定轴旋转的线阵ＣＣＤ及微机系统自动测定激光干涉环圆心位置及应用于激光外径千分尺平行度检查仪平行度检查结果的自动数字化输出。     

天线方向图的复射线仿真

根据复射线理论，利用复源点高斯波束场来模拟天线的远场方向图。本文提出三种模拟方法，即主瓣匹配法，峰值匹配法和逐点匹配法，给出了多种方向图的仿真结果。数值分析和优化结果表明，复射线峰值匹配法是一种精确实用的天线方向图仿真技术。     

微波BJT超宽带低噪声放大器的设计

本文给出了一种频带覆盖达１０－１６００ＭＨｚ的微波ＢＪＴ超宽带低噪声放大器的设计方法，从微波ＢＪＴ的噪声模型出发，通过拟合５０Ω源阻抗下微波ＢＪＴ的噪声系数ＮＦ５０和Ｓ参数来提取其噪声参数，然后根据增益，噪声及驻波比要求优化设计放大器，使放大器在超宽带范围内获得平坦增益和低噪声，本文所给出的微波ＢＪＴ惨数提取及放大器优化设计方法已由实验结果所验证。     

微机在应变测量中的应用

微机在应变测量中的应用，采用上位机和下位机组合方式．上位机为一台ＩＢＭ－ＰＣ／ＸＴ微机，用于对数据进行后处理．下位机以Ｚ８０－ＣＰＵ为控制器，由传感器、转换器、接口及外设等组成数据采集器，实施对应变、压力和位移等参数的采集、显示和打印（即数据的预处理）．上位机和下位机之间的数据传输，采用串行的方式，通过ＲＳ－２３２接口完成．本文主要以应变的采集处理为例，介绍系统功能、硬件配置及软件设计．     

一种智能化的键盘练习器

本文介绍了一个利用单片机研制的键盘操作练习器。它能完成健盘输入练习和输入水平测试二项功能。     

四路激光跟踪测量系统最佳测量区域和系统自标定

研究了系统最佳布局下的最佳测量区域问题,给出了几何精度衰减因子PDOP在三维空间内的变化规律。通过计算机仿真研究了最佳测量布局对系统自标定的影响规律,指出最佳测量布局中的标称配置对系统自标定精度的影响最小,同时这种布局有着最小的几何精度衰减因子。