一种新的中间继电器交替通断的设置方法

中间继电器在步进式控制线路中交替通断的设置方法是一种新的设置法，采用这种设置法，所需中间继电器的数量约为控制线路在一个工作周期内整个步数的１／２。因此，所需数量较少，由此设计的控制线路成本较低。通过一个具有５步程序的步进式控制线路的设计实例，对交替通断设置法的概念、运用和效果作了详细介绍。     

控制Excel生成报表的技术分析

对控制Excel生成报表的技术进行了详细的分析，完美地解决了生成复杂报表的问题。     

使用Gantt图建立EPC工作流模型的研究

论文结合建筑工程项目的特点,讨论如何使用广义Gantt图建立基于EPC的工作流过程模型,旨在为建筑工程项目的工作流管理提供一个新的思路。     

本底个值质控图在放免仪长期稳定性监控中的应用

在放免仪短期稳定性评价的基础上制作了本底个值质控图并应用于长期稳定性的监控。结果表明，该方法可作为放免仪长期稳定性考核、量化的一个手段。     

PID控制技术在砌块养护窑中的应用

本文介绍了一种利用S7-200型PLC的PID控制技术来实现砌块养护窑的自动控制系统，详细介绍了系统的硬件配置以及软件设计流程图，并根据模拟实验的编程经验．介绍了编程中的关键问题。     

Genetic algorithms combined with discriminant analysis for key variable identification

Many trouble-shooting problems in process industries are related to key variable identification for classifications. The contribution charts, based on principal component analysis (PCA), can be applied for this purpose. Genetic algorithms (GAs) have been proposed recently for many applications including variable selection for multivariate calibration, molecular modeling, regression analysis, model identification, curve fitting, and classification. In this paper, GAs are incorporated with Fisher discriminant analysis (FDA) for key variable identification. GAs are used as an optimization tool to determine variables that maximize the FDA classification success rate for two given data sets. GA/FDA is a proposed solution for the variable selection problem in discriminant analysis. The Tennessee Eastman process (TEP) simulator was used to generate the data sets to evaluate the correctness of the key variable selection using GA/FDA, and the T² and Q statistic contribution charts. GA/FDA correctly identifies the key variables for the TEP case studies that were tested. For one case study where the correlation changes in two data sets, the contribution charts incorrectly suggest that the operating conditions are similar. On the other hand, GA/FDA not only determines that the operating conditions are different, but also identifies the key variables for the change. For another case study where many key variables are responsible for the changes in the two data sets, the contribution charts only identifies a fraction of the key variables, while GA/FDA correctly identifies all of the key variables. GA/FDA is a promising technique for key variable identification, as is evidenced in successful applications at The Dow Chemical Company.     

测量过程统计控制

过程方法是IS09000：2000阐明的管理原则，测量过程被认为是支持组织产品质量的特定过程。如生产过程一样，测量过程中存在变异。这些过程要素和控制应包括操作者、设备、环境条件和应用方法的影响。包括核查标准的休哈特控制图是重要和有效的控制手段。文章介绍了休哈特控制图在测量过程中应用的基本原理。     

A Multivariate T2 Control Chart for Skewed Populations Using Weighted Standard Deviations

This paper proposes a heuristic method of constructing multivariate T² control charts for skewed populations based on ‘weighted standard deviations’, obtained by decomposing the standard deviation into upper and lower deviations according to the direction and degree of skewness. The proposed method adjusts the variance–covariance matrix of quality characteristics and modifies the ellipsoidal probability density function contour of the multivariate normal distribution to a shape similar to that of the skewed distribution. False alarm rates and out‐of‐control average run lengths of the proposed control chart are compared with those of the standard control chart for multivariate lognormal, Weibull and gamma distributions, and the results show that considerable improvement over the standard method can be achieved when the distribution is skewed. Copyright © 2003 John Wiley & Sons, Ltd.     

可变样本容量和抽样区间的和R控制图

最近的理论研究证实了具有可变抽样区间(VSI)的过程控制图和可变样本容量(VSS)控制图比常规控制图(FSSI)能较大地提高控制图的效率。文章假定过程处于统计控制状态的时间t服从负指数分布:f(t)=λe-λt(t≥0),利用Costa的马氏链方法[1],设计具有可变样本容量和抽样区间(VSSI)的中位值(x)和极差(R)图。所设计的控制图较之常规控制图能更快地发现过程的变化,从而大大地降低不合格品数。     

加工中心自动换刀系统可视化程序设计

介绍了用 Visual Basic6.0进行数控机床自动换刀过程的演示软件的设计与实现过程.基于自动换刀过程中各种动作的逻辑关系,做出系统分析,并以刀库为例,给出具体设计与实现步骤.