Note on ‘Construction of Double Sampling s‐Control Charts for Agile Manufacturing’

He and Grigoryan (Quality and Reliability Engineering International 2002; 18 :343–355) formulated the design of a double‐sampling (DS) s control chart as an optimization problem and solved it with a genetic algorithm. They concluded that the DS s control charts can be a more economically preferable alternative in detecting small shifts than traditional s control charts. We explain that, since they only considered the average sample size when the process is in control, their conclusion is questionable. Copyright © 2006 John Wiley & Sons, Ltd.     

重视过程控制工程安装材料的选择

本文结合工程介绍了自动化仪表工程设计中常用安装材料的正确选择方法和选择不当可能造成的危害。     

SUPMAX500系统在锅炉控制系统中的应用

针对动力厂35t/h锅炉的工艺控制要求，选用SUPMAX500集散控制系统。介绍了系统的软、硬件构成及其具体实施方法。     

CDMA系统中联合功率控制、波束赋形与多用户检测

应用功率控制、波束赋形和多用户检测可以有效地消除和减少CDMA系统中的干扰。本文结合波束赋形和多用户检测的特性，提出一种应用波束赋形增益和多用户相关矩阵的解相关算法。基于算法的复杂性，提出一种区分聚集用户进行多用户检测的的算法。由于波束赋形能够消减主瓣波束之外的多用户干扰，对聚集移动台采用解相关检测达到减少运算量和消除多用户干扰的目的。对算法进行了仿真分析，证明了本算法的优越性。     

The Difference in Turbulent Diffusion between the Active and Passive Scalars in a Thermally Stably Stratified Medium

The difference in the turbulent diffusion between the active (heat) and passive (mass) scalars in a thermally stably stratified medium is investigated. The axisymmetric problem is treated on the formation of a turbulent circulation flow above a heated disk and on the turbulent diffusion of a passive scalar (impurity) from a continuous surface source in a stably stratified medium. The results indicate that the thermal stratification causes appreciable differences in the coefficients of turbulent transfer between the active (heat) and passive (mass) scalars. This means that the assumption of the identity of the coefficient of turbulent diffusion of heat and mass, employed in conventional models of turbulence, produces significant errors in estimating the heat and mass transfer in a thermally stably stratified medium.     

浅谈炼钢车间的自动控制系统

介绍了天津钢铁工业结构调整改造后的新钢铁企业炼钢车间的自动控制系统，系统的配置、主要功能，并对系统做出评价。     

盐井水平对接钻井技术

钻一口通过主采盐层的水平井与已完成的直井对接，形成连通井(形如“U”字)，一口井注水溶解盐／芒硝矿，另一口井采出卤水，这是盐化工业对钻井提出的要求。针对水平对接盐井井身轨迹设计、着陆段、水平段的轨迹控制和连通技术，介绍了水平段侧钻时的钻井液技术。     

谢尔渣油气化油改气控制系统的改造

介绍了Shell渣油气化装置将渣油原料改为天然气时控制系统的改造方案。提出的改造思路不但可用于Shell渣油气化，也可用于德士古渣油气化的油改气工程中。     

KMLS型立式砂泵的振动噪声产生原因及解决措施

针对KMLS型立式砂泵振动、噪声产生原因及其表现特征,提出了解决措施。通过对这些原因的分析研究,可以提供泵设计者和生产者在减少砂泵振动方面采取相应的措施,使KMLS型立式砂泵能更好的服务于用户。