轮式工程机械的行驶平稳性

根据振动理论建立了振动力学模型,并用等效刚度方法分析研究了弹性悬挂轮式工程机械行驶平稳性和振动特性。     

毫米波谐波振荡器的多模Volterra级数分析

本文基于Ｖｏｌｔｅｒｒａ级数和非线性转移函数理论，提出了一种分析毫米波谐波振荡器的新方法一多模Ｖｏｌｔｅｒｒａ级数法，并给出了描述其非线性特性的决定方程，通过求解一组非线性代数方程，便可计算出谐波振荡器的振荡频和幅度。文中给出了分析实例并与谐波平衡法等进行了比较，结果表明：这种方法具有理论严密、准确性高，适用范围广等特点特别是利用一次决定方程的结果作为其它非线性数值分析方法的初始估值，可大大地节约     

Enhancement of oxide break-up by implantation of fluorine inpoly-Si emitter contacted p+-n shallow junctionformation

In this study, it is demonstrated that the incorporation of fluorine can enhance poly-Si/Si interfacial oxide break-up in the poly-Si emitter contacted p⁺-n shallow junction formation. The annealing temperature for breaking up the poly-Si/Si interfacial oxide has been found to be as low as 900°C. As a result, the junction depth of the BF₂-implanted device is much larger than that of the boron-implanted device     

Coincident indices of exons and introns

In this paper, the coincident index, proposed by W. F. Friedman in cryptology, is made use of in DNA sequence analysis and exon prediction. The coincident index of exons exceeds that of introns by many times, and is mainly affected by window length, which is correlated negatively with the coincident index. An optimal exon prediction scheme was obtained by experimental analysis with an orthogonal table. Besides exons, many other special sites such as tandem repeats can be identified by using the coincident index approach. The application of this approach to the ARV-2 (AIDS associated retrovirus 2) genome found three new possible coding regions and some unusual base composition regions which are probably related to definite biological functions.     

大电流监测信号提取的光收发及信号处理

近年来,大电流的监测成了人们十分关心的问题,这是由于大电流有强磁、高压、电流大等一系列的直接监测所不能克服的问题。这就需要把高压大电流的强电信号,经过提取后变成能在实验室中直接观测的弱电信号。为此,如何从高压大电流的信号中提取出随实时信号变化而实时变化的小信号就变成了一个关键问题。详细介绍了监测信号提取的光收发电路原理和后续信号处理电路,分析了各部分的作用,给出了必要的分析结果。     

Monte Carlo simulation of grain growth and recrystallization in polycrystalline materials

The prediction and control of metal grain structures during processing have been major objectives of materials science. However, methodologies that are accurate and can be easily generalized to a variety of processing conditions have been difficult to formulate due to the complexity of the grain interactions. A novel Monte Carlo-based approach that explicitly incorporates these interactions has been developed to simulate the microstructural evolution driven by the minimization of grain boundary energy and lattice defect density. The applicability of this procedure has been demonstrated by the good correspondence between simulation results and experimental observations. This article reviews recent advances in the application of this technique to the investigation of a variety of phenomena, including normal and abnormal grain growth as well as static and dynamic recrystallization.     

SIMATIC S5—115U可编程控制器

本文通过对SIMATIC S5—115U可编程控制器性能的简介,简述国外PC技术的现状和发展,并提出对PC国产化的看法.     

镁质瓷泥浆流变性能的改进

滑石质瓷是一种高性能瓷的材料，但由于其泥浆的稠化性及泥料塑性差，阻碍了滑石质瓷的大量生产。实验表明：引入长石作助熔剂并加入适量粘土，可以改进泥料塑性及泥浆流变性能，使烧成变形度小，机械强度提高，能较好地满足制品成型的工艺要求。实验中设计了多组配料，分析比较烧后试样的性能测试结果，确定最佳配方及烧结温度。     

基于改进PSO算法的结构损伤检测

结构的损伤检测常转化为求解约束优化问题,针对粒子群算法容易出现早熟问题,增大算法后期的粒子位置的改变量,从而增加粒子位置的差异,因而能够增强其在求解约束优化问题时抵抗局部极小的能力。两层刚架单损伤和多损伤识别的数值结果和收敛曲线表明了改进后的粒子群算法优于传统的带惯性因子的粒子群算法。三层框架结构的4种损伤工况的试验研究进一步说明了该算法应用于结构损伤检测领域的有效性。