HP6890系列气相色谱仪分析炼厂气

本文介绍两种分析炼厂气的方法:一种是传统的由几个步骤组成的方法;另一种用HP6890系列气相色谱仪分析,这种方法能一次完成分析,快速而准确。此文还讨论了在分析过程中应用注意的几个问题。     

Elastic-plastic analysis of crack in adhesive joint by combination of boundary element and finite element methods

This paper concerns with a combination method of the boundary element method and the finite element method for elastic-plastic analyses. The combination method proposed here is based on the substructure method using the conjugate gradient method. This combination method has the advantage of saving CPU time and memory storage size over the finite element method. The combination method is applied to a J-integral analysis of a crack in an adhesive joint. The effect of bond thickness on the J-integral is discussed.     

多度系统振动问题的状态方程解法

本文介绍一种有别于模态分析法的直接积分法。介绍了多自由度线性系统运动微分方程化为状态方程的方法．介绍了状态方程的解法以及其离散化后的迭代法，给出了计算框图。     

求解结构动力反应的样条函数法

求解结构动力反应问题的样条函数法是作者1980—1981年提出来的,现在又有不少新的进展。本文主要介绍这个方法的基本原理及其应用,其中包括样条最小二乘法、样条伽辽金法、样条配点法、样条最小二乘配点法及样条伽辽金配点法。这些方法容易在电子计算机上实现,利用小型或微型计算机可以解题,不仅计算简便,而且精确度也高,能满足工程上的精确度要求。本文只考虑线性问题。     

Quick Determination of Thermal Conductivity of Potting Compounds by a Transient Technique

This paper is based on a study made by the author of a simple and reasonably accurate transient method for determining the thermal conductivity of potting compounds. This method used a cylindrical test specimen with axial heat addition. The shape of the specimen described in this report has no bearing on the measurement as long as the specimen is of sufficient size. This paper presents mathematical proofs of the transient method studied, describes apparatus for making tests, and gives comparative results between transient method and steady-state method.     

一种简便有效的曲面拟合方法及其成像技术

本文旨在论述一种新的、简便有效的曲面拟合方法,该方法是建立在拉格朗日三次曲线拟合方法之上,通过在x和y两个方向同时作曲线拟合,构成一个空间曲面。文中还讨论了该空间曲面的成像技术。经编程验证,此法具有计算量小,拟合精度高,拟合出的曲面光滑等优点,有很好的实用价值。     

弹性力学的样条边界元法

本文对弹性力学问题提出一个样条边界元法。文中用三次B样条函数来逼近边界未知量,并且利用域外奇点法建立了样条边界元法的计算格式。这种计算格式十分简单,容易在微机或小机上实现。利用域外奇点法建立起来的计算格式,完全可以避免奇异积分。计算结果表明,样条边界元法是一个经济有效的计算方法。     

Multidimensional numerical integration for meshless BEM

The conventional boundary element method (BEM) uses internal cells for the domain integrals, when nonlinear problems or problems with domain effects are solved. In the conventional BEM, however, the merit of the BEM, which is easy preparation of data, is lost. This paper presents numerical integration for a meshless BEM, which does not require internal cells. This method uses arbitrary internal points instead of internal cells. First, a multidimensional interpolation method for distribution in an arbitrary domain is shown using boundary integral equations. This method requires values on a boundary of a region and values at arbitrary internal points. In this paper, multidimensional numerical integration is proposed using the above multidimensional interpolation method. This integration is useful for inelastic problems and thermal stress analysis with arbitrary internal heat generation. This method is based on an improved multiple-reciprocity BEM (triple-reciprocity BEM) for heat conduction analysis with heat generation. In order to investigate the efficiency of this method, several numerical examples are given.     

一种新的二维图像测量系统标定方法

本文提出了一种新的网络式平行线标定方法 ,该方法采用了CCD亚像素细分技术及调焦技术 ,可直接得到纵横两个方向的像素当量 ,具有标定简单、精度高、重复性好等优点。本文对方法的精度进行了较详细的分析 ,并给出了实验结果。     

基于量块的步距规测量及不确定度分析

提出了一个使用电感测微仪在平板上与量块比较的步距规测量方法,并分析了其测量不确定度。该方法将对步距规的应用和测量起到积极的推动作用。     

Estimation of dispersion effects from robust design experiments with censored response data

A method is presented for estimating dispersion effects (DE) from robust design experiments (RDE) with control and noise factors involving censored response data. This method is developed to discern the significance of DE from RDE and the method aims at analyzing a multi‐level/multi‐factor experiment. This method imputes censored data by a regression based imputation technique, assuming that the distribution of lifetime before and after censoring is identical. This method also models the residuals to identify important DE, assuming that the distribution of the observed random variables of the model is the same with or without censored response data. Finally, the method is demonstrated through a numerical example. Copyright © 2001 John Wiley & Sons, Ltd.     

基于DSP TMS320F240的浮点数开方的研究

研究DSP TMS320F240浮点数开平方的理论方法，采用牛顿迭代法完成浮点数开方运算。在DSP TMS320F240上编制了一套算法，其结果基本符合理论要求。该方法思路新颖、精度高、速度快，可移植到其它浮点数运算的单片机上。     

Analysis of Confidence Lower Limits of Reliability and Hazard Rate for Electronic Stability Control Systems

This article describes an evaluation method for reliability and hazard rate of lifetime distribution confidence lower limits for electronic stability control (ESC) system using test data from multistage and subsystems. This method provides estimation that can potentially and significantly reduce the amount of testing, without sacrificing the one‐sided confidence level of reliability. This also allows quicker design verification and validation for ESC systems. The method is derived under the assumption that the reliability parameter is a random variable with a given distribution function, and the product's reliability increases monotonously during the development process. This new method is applied to the analysis of reliability of an ESC system. Copyright © 2012 John Wiley & Sons, Ltd.     

机器人机构运动学方程的完全解及其运动设计方案的优选

简述了一种能求得非线性方程组完全解的数值方法－－连续法的基本原理及其发展状况，该方法既能可靠求得机械运动学方程的全部精确解。又有用于求机构优化设计的全部优化解，从而有利于机构运动设计方案的优选，同时对其他各学科中的非线性问题的求解也具有重要参考价值。     

Linear and nonlinear generalized Fourier transforms

This article presents an overview of a transform method for solving linear and integrable nonlinear partial differential equations. This new transform method, proposed by Fokas, yields a generalization and unification of various fundamental mathematical techniques and, in particular, it yields an extension of the Fourier transform method.     

基于拟静态初值的载荷识别数值修正算法

推导拟静态法获得载荷初值及稳定不发散计算结果,分析获得初值不准确原因,推导获得新的载荷识别方法。该方法基于数值原理,利用步步修正达到减少累积误差效果,可较大程度提高计算稳定性,并将数值迭代修正方法用于有限元模型载荷识别。结果表明,该方法能较准确识别出工程中常见的多种载荷,并具有一定抗噪能力。     

包装容器造型中的一种设计方法

给出了一种新的包装容器造型方法－－自由变形方法（ＦＦＤ）。该方法在包装容器曲面外形设计初期,可以直观、简洁、方便地获得高阶连续的曲面实体,该方法在包装容器造型设计方面具有广阔的发展前景。     

流动分析法测定水中硫化物

本文介绍了连续流动分析法测定水中硫化物的过程,方法中硫化物通过与二盐酸-二甲基苯二胺和氯化铁反应生成亚甲基蓝,在660nm下用光度法检测。此方法具有重现性好灵敏度高的特点。回收率为98~104%,相对标准偏差小于2.8%。     

以氯化铁为前驱态催化剂制备碳纳米管

利用氯化铁为催化剂前驱体,结合悬浮催化剂法和基体法的优点,采用一种我们称之为悬浮-基体的新方法在700℃生长出了管壁清洁、直径均匀的碳纳米管,同时实验结果和分析证明,对所沉积的催化剂铁颗粒用氢气进行预处理具有细化碳纳米管和减少碳纳米管缺陷的作用。实验显示这种以氯化铁为催化剂前驱体的悬浮-基体法是一种很有前途实现碳纳米管廉价、大批量生产的方法。     

A new hybrid method for solving linear–non‐linear systems of equations

This paper presents a new method for solving any combination of linear–non‐linear equations. The method is based on the separation of linear equations in terms of some selected variables from the non‐linear ones. The linear group is solved by means of any method suitable for the linear system. This operation needs no iteration. The non‐linear group, however, is solved by an iteration technique based on a new formula using the Taylor series expansion. The method has been described and demonstrated in several examples of analytical systems with very good results. The new method needs the initial approximations for non‐linear variables only. This requires far less computation than the Newton–Raphson method. The method also has a very good convergence rate. The proposed method is most beneficial for engineering systems that very often involve a large number of linear equations with limited number of non‐linear equations. Copyright © 2005 John Wiley & Sons, Ltd.