Consumers risk and quality control in a collaborative supply chain

The purpose of this paper is to provide a strategic collaborative approach to risk and quality control in a cooperative supply chain by using a Neyman–Pearson quantile risk framework for the statistical control of risks. The paper is focused on the statistical quality control of a supplier and a producer, applying the traditional Neyman–Pearson theory to the control of quality in a supply chain environment. In our framework, the risks assumed by the parties in the supply chain depend on the organizational structure, the motivations and the power relationships that exist between members of the supply chain.     

Cost-optimal multistage sampling plans in statistical quality control

Multistage Bayesian decision procedures in statistical quality control are known from attribute sampling. In this paper they are introduced in a more general framework occuring in lot-control by using the theory of Bayesian sequentially planned decision procedures. We show that under sufficiency and transitivity assumptions and monotonicity properties concerning the distribution and cost set-up these Bayes-procedures have (z, c ^–,c ⁺)-structure which, on one hand, generalizes results of K.-H. Waldmann and, on the other hand, reduces computational effort significantly. Finally, examples taken from attribute sampling and life testing for an outgoing lot are presented.The theory presented in this paper is taken from [11].     

Statistical quality control and improvement

Quality has become a key determinant of success in all aspects of modern industry, services as well as manufacturing. This paper reviews the contributions of statistical analysis and methods to modern quality control and improvement. The two main areas are statistical process control and industrial experimentation. The statistical approach is placed in the context of recent developments in quality management, with particular reference to the Total Quality movement.     

Fractionally differenced models for water quality time series

This paper deals with the selection and evaluation of statistical techniques for use in the modeling and forecasting of water quality time series. The focus is on statistical concepts relevant to the analysis of flows and concentrations. A selection of time series procedures has been used for auditing water quality archival data, including the screening of data sets, correlation and spectrum calculations, and iterative model fitting. A summary is provided of experience with analyzing archival data on the Niagara River and the use of a fractionally differenced model.This paper is the result of a study performed for the International Joint Commission, United States and Canada. The authors gratefully acknowledge the direction and support provided by Dr. Joel L. Fisher.     

基于主成分原理的多元质量控制图的构造

控制图是从事统计质量管理经常使用的重要工具,经过多年的发展和实践,一元质量控制图业已得到普遍推广,可是如何开展多元质量控制仍有许多问题值得探讨。在这篇文章中,我们着重讨论了基于主成分分析的多元质量控制图的构造,并结合从企业现场采集到的数据给出了具体的应用说明。     

基于灰色模型和Bootstrap理论的大规模定制质量控制方法研究

针对大规模定制生产中样本量小而无法直接应用传统控制图判断过程状态的问题,提出基于灰色模型和Bootstrap理论的质量控制方法.首先采用灰色模型,以现有样本为基础进行数据分析,适当扩展样本量;然后基于Bootstrap统计推断方法获得统计量的经验分布;最后建立样本均值和极差控制图,对生产过程的状态进行分析判断.研究表明,新方法可用于大规模定制生产尤其是新型号生产初期的质量预测和控制.     

质量控制图原理在股票投资组合中的应用研究

质量控制图是用来控制生产过程质量的一种统计方法。其基本理论方法应用到股票投资组合中,可以降低投资风险,提高投资组合的收益率。通过实证研究表明:利用质量控制图原理来确定投资组合的选股、买点和卖点,可以使投资组合获得明显高于大盘指数的收益率,从而验证了质量控制图的基本理论方法完全可以应用于股票投资决策,并且具有显著的实际应用价值。     

图书编校质量控制模型

建立了图书编校质量控制的统计模型,可用其讨论达到某种质量标准所需校对次数和对校对人员的素质要求,有助于制订量化的质量管理方案.     

基于产品质量控制的设备维修优化模型

根据产品质量和生产该产品的设备退化状态之间的相关性,设计了周期性设备检测与产品质量控制相结合的设备维修策略。该策略是在对设备进行周期性检测的基础上,利用控制图进行产品质量异常波动的检测,结合对设备退化状态的检测选择设备应采取的维修活动。根据这一设备维修策略,利用更新过程理论和统计过程控制方法,构建了基于产品质量控制的设备维修优化模型,并用遗传算法对其进行求解。通过实例仿真验证了该模型的可行性与有效性。     

Sequential sampling schemes and other statistical techniques in quality of service business surveys

While there is a general consensus in the business community regarding the importance of quality service surveys in improving the company's business results, relatively little attention was devoted to the theoretical aspects of data analysis and modelling which can increase substantially the effectiveness of those surveys. Using the data from a real‐life project, we present here the developments and improvements achieved in the three stages that ultimately yield the conclusions from the survey: the analysis of the historical data, the design of the sampling method for the current survey and the development of specific indices for differentiating among the units of the financial institution. The statistical techniques fitted to historical data helped both in assessing the relative contributions of the various aspects of service, the overall perceived quality of service, as well as in providing the theoretical grounds for reducing the size of the questionnaire and thus increasing the reliability of the received replies. The sequential sampling scheme designed for this survey was particularly suitable to address the managements concerns. Finally, the classes of quality service based on the quality indices developed in the project contributed substantially to the ability of the management to rank and reward differentially the branches of the financial institution. Copyright © 2002 John Wiley & Sons, Ltd.     

Analysis of triangle quality measures

Several of the more commonly used triangle quality measures are analyzed and compared. Proofs are provided to verify that they do exhibit the expected extremal properties. The asymptotic behavior of these measures is investigated and a number of useful results are derived. It is shown that some of the quality measures are equivalent, in the sense of displaying the same extremal and asymptotic behavior, and that it is therefore possible to achieve a concise classification of triangle quality measures.

     

Study and modelling of two apple quality attributes: the soluble solids content and the firmness

Recently, the basic dynamics of fruit characteristics have been modelled using a stochastic approach. The time evolution of apple quality attributes was represented by means of a system of differential equations in which the initial conditions and model parameters are both random. In this work, a complete study of two apple quality attributes, the soluble solids content and the firmness, is carried out. For each of these characteristics, the system of differential equations is linear and the state variables and the parameters are represented as random variables with their statistical properties (mean values, variances, covariances, joint probability density function) known at the initial time. The dynamic behaviour of these statistical properties is analysed. The variance propagation algorithm is used to obtain an analytical expression of the dynamic behaviour of the mean value, the variance, the covariance and the probability density function. A Monte Carlo method and the Latin hypercube method were developed to obtain a numerical expression of the dynamic behaviour of these statistical quantities and particularly to follow the time evolution of joint probability density function which represents one but the best mean to characterize random phenomena linked with fruit quality attributes.     

基于时间序列的挖掘算法在流程工业产品质量控制模型中的应用

针对目前流程工业产品质量控制采用人工检查和统计质量控制方法,缺乏产品质量预先预报以及时时调整生产过程的工艺参数存在一定困难.利用生产过程采集到的实际数据,采用基于时间序列的动态数据挖掘技术和BP神经元网络,预测产品质量和分析产品生产过程的工艺,最大限度减少不合格产品的产出,提高生产效率.根据上述理论建立流程工业数据动态质量控制平台,以中厚钢板生产过程为例,应用表明了这种方法在实际应用中的正确性和有效性.     

Monitoring process for attributes with quality deterioration and diagnosis errors

The aim of this paper is to present an online economical quality-control procedure for attributes in a process subject to quality deterioration after random shift and misclassification errors during inspections. The process starts in control (State I) and, in a random time, it shifts to out of control (State II). Once at State II, the non-conforming fraction increases according to a non-decreasing function ψ(z), where z is the number of items produced after a shift. The monitoring procedure consists of inspecting a single item at every m produced items, which is examined r times independently to decide its condition. Once an inspected item is declared non-conforming, the process is stopped and adjusted. A direct search technique is used to find the optimum parameters which minimize the expected cost function. The proposed model is illustrated by a numerical example. Copyright © 2007 John Wiley & Sons, Ltd.     

一种出版物质量控制的统计方法

本文利用统计方法给出了一种控制出版物质量的方法。这种方法对于提高我国出版物质量有参考价值.     

An approach to measuring the quality of maintenance performance

^** Email: sa_oke{at}yahoo.com This paper presents an approach that quantifies the performanceof the maintenance system in terms of the quality of service,offered by maintenance to the production system. Maintenanceis discussed as involving both technical and economic issues.This influences the definition of maintenance quality and maintenanceperformance used in this work. This is because maintenance canbe considered of high quality if the latter is measured (orevaluated) by only technical terms such as quality rate. However,this does not necessarily mean that maintenance is so when itsperformance is measured in economic terms. This issue is importantand is highlighted in the paper. The motivation for writingthe paper is the need for a scientific means of conflict resolutionbetween the maintenance and production department. There arefrequently complaints from the production department that thequality of the machines soon after maintenance is sometimespoor, thus leading to a shortened period of production. Themethodology adopted hinges on the framework in which scrap generation,rework and reject are partly due to the malfunction of the machine.Thus, if a machine has a deteriorated state soon after maintenance,it is likely to produce rejects, scrap or reworked materials.It is argued that the measurement of performance using thisapproach is helpful and could be used for planning purposes.The approach utilized in this work is new, and represents acontribution to the maintenance performance literature.     

The price of quality claims

Quality claims and quality in fact of financial and industrial products as well as financial and business services are essential to entice and attract customers. For these reasons, firms are often tempted to assert claims that might or might not be met. These claims have risks which cannot always be prevented when interpreted as a ‘sure thing’ while in fact, quality performance is probabilistic. This paper considers a financial (utility based) approach to pricing a quality claim. To do so, we assume that ex‐ante, a true quality performance is defined by a density function while claims are advertised—setting expectations for a quality performance. On the basis of these assumptions we determine the price associated with such claims. Copyright © 2010 John Wiley & Sons, Ltd.     

多维统计数据质量检验与异常点识别的模型与方法

本文证明 ,反映社会经济规模大小的多维统计数据近似服从多维对数正态分布 .基于此 ,本文提出了对这类数据的质量及其异常点进行检查和识别的多维对数正态分布检验法 ,并以我国中央部门属研究机构的调查数据为例进行了研究     

The relationship between quality management practices and their effects on quality outcomes

Recent research into quality management has examined the relationship between quality management and performance. The purpose of this study is to identify the relationships between quality management practices, and to examine the direct and indirect effects of these practices on quality outcomes by means of replication research. The paper uses a path analysis and a research model is tested using cross-section data collected from 106 certified firms in Spain. The findings support the relationships between quality management practices and the positive impact of these practices on quality outcomes. Evidence is also found confirming previous research showing that a firm could transfer the organizational forms and behaviours underlying quality management to other countries with similar cultures. However, as minor differences emerge, managers should consider the cultural issues. The contribution of the paper is that it provides empirical support for direct and indirect effects of quality management on performance in Spain compared to previous studies carried out in USA and Korea.     

Empirical study for the agreement between statistical methods in quality assessment and control of microarray data

As microarray data quality can affect each step of the microarray analysis process, quality assessment and control is an integral part. It detects divergent measurements beyond the acceptable level of random fluctuations. This empirical study identifies association and correlation between the six quality assessment methods for microarray outlier detection used in the arrayQualityMetrics package version 2.2.2. For evaluation two different agreement tests—Cohen’s Kappa, after a homogeneity marginal criteria, and AC1 Statistic—, the Pearson Correlation Coefficient and realistic microarray data from the public ArrayExpress database have been used. It is possible to assess the quality of a data set using only four of the six currently proposed statistical methods to comprehensively quantify the quality information in large series of microarrays. This saves computation time and reduces decision complexity for the analyst. The new proposed rule is validated with data sets from biomedical studies.