激光散斑相位差的条件统计分布与表面粗糙度的关系

在粗糙表面高度起伏服从高斯统计和表面服从圆型相关的情况下，分析了由弱散射体产生的远场高斯激光散斑相位差的条件统计分布与表面粗糙度的关系．     

Smoothed Histograms for Frequency Data on Irregular Intervals

Frequency tables are often constructed on intervals of irregular width. When plotted as bar charts, the underlying true density information may be quite distorted. The majority of introductory statistics texts recommend tabulating data into intervals of equal width, but seldom caution the consequences of failing to do so. An occasional introductory text correctly emphasizes that area rather than frequency should be plotted. Nevertheless, the correctly scaled density figure is often visually less informative than one might expect, with wide bins at constant height. In many cases, the right most bin interval has no well-defined end point, making its depiction some what arbitrary. In this note, we introduce a regular histogram approximation that matches the frequencies and also minimizes a roughness criterion for visual and exploratory appeal. The resulting estimate can reveal the density structure much more clearly. We also formulate an alternative criterion that explicitly takes account of the uncertainty in the bin frequencies.     

辐射计观测模拟系统的设计与研究

基于物理参数反演和卫星数据同化系统的发展需要,设计了一个结合陆面、大气和传感器特征,基于辐射传输模型的辐射计观测数据模拟系统。综合考虑地形、地表异质性、大气等影响,可以直接应用到数据同化系统,进而为校正数据同化模式的静态参数提供基础,同时提高对辐射机理的理解和认识,促进地球物理参数反演。利用该模拟系统,模拟了先进微波扫描辐射计(AMSR-E)的全球观测,并与卫星实测数据进行了对比,对粗糙度进行敏感性分析,其影响可达38 K。     

On Quasi Likelihood Equations with Non-parametric Weights

To apply the quasi likelihood method one needs both the mean and the variance functions to determine its optimal weights. If the variance function is unknown, then the weights should be acquired from the data. One way to do so is by adaptive estimation, which involves non-parametric estimation of the variance function. Adaptation, however, also brings in noise that hampers its improvement for moderate samples. In this paper we introduce an alternative method based not on the estimation of the variance function, but on the penalized minimization of the asymptotic variance of the estimator. By doing so we are able to retain a restricted optimality under the smoothness condition, however strong that condition may be. This is important because for moderate sample sizes we need to impose a strong smoothness constraint to damp the noise—often stronger than would be adequate for the adaptive method. We will give a rigorous development of the related asymptotic theory, and provide the simulation evidence for the advantage of this method.     

光纤探针式轮廓仪的理论与实验研究

在单根单模光纤作为发射光纤兼接收光纤的情况下,提出了光纤探针式轮廓仪,得到一个光纤探针来测量被测表面的微观轮廓曲线,并由轮廓曲线得到了表面粗糙度的各种参数和光纤探针的形状和尺寸。同时阐述了利用光纤探针测量表面轮廓和粗糙度的原理及光纤探针式轮廓仪的构成和工作原理,给出了测量结果。     

用光学仪器测量表面粗糙度参数的微机处理方法

本文利用ＢＡＳＩＣ语言编制了一套应用程序，可利用光切显微镜实测的数据，得到国家标准规定的六个参数。     

高速公路沥青路面行驶质量评价方法的探讨

路面行驶质量是影响行车安全和舒适的重要因素。通过对以往研究的概述,指出目前对路面行驶质量评价的不足。建议在评价路面行驶质量时引入驾乘人员的心生理指标，从人的角度定量研究路面     

基于正交试验法研究乳化炸药螺杆泵螺杆加工三要素

针对主轴转速、进给速度、背吃刀量切削三要素不同值影响螺杆表面粗糙度规律,剖析传统的依靠人工经验选择三要素存在人为缺陷及遗传算法优化选择三要素需大而全的数据库难以实现的现状,探讨一种科学简单、易于实现的正交试验法应用于筛选三要素的优化组合,通过设计3因素3水平试验并对数据进行数理统计分析计算,得出三要素中背吃刀量对螺杆表面质量影响最显著,主轴转速对其影响非显著的结论,研究出的三要素最优值组合能确保螺杆加工表面质量、提高工效,对实际生产具有一定的指导意义。     

微型管内摩擦特性的实验研究

以水、乙醇及四氯化碳作为工质，流过内径分别为0．168mm、0．399mm和0．799mm不锈钢管及内径分别为0.242mm、0．315mm和0．52mm石英玻璃管，测量其压降与流量，从而获得摩擦系数厂与雷诺数Re的关系．实验结果表明，当Re小于1200～1800时，除内径为0．168mm的不锈钢管外，其他微管内的与经典层流理论值几乎一致；而对于内径为0．168mm，相对粗糙度为8％～10％的不锈钢管，当Re超过800时，其值比经典理论值高10％～15％；当Re超过1800时，所有微管的厂值明显偏离经典层流理论值．     

机械零件图样的粗糙度标注在AutoCAD中的自动生成

本文介绍了利用AutoCAD的二次开发工具块和AutoLisp语言来解决在用AutoCAD绘制机械零件图样时遇到的粗糙度的标注问题