Guidelines for automating Phase I of control charts by considering effects on Phase-II performance of individuals control chart

Atalay, Murat
Duran, Serhan
Weiss, Christian H.
With the advances in measurement technologies, today products and processes may have hundreds of variables that can be monitored. As the number of variables to be monitored in a process increases, a cumbersome task is the design of control charts, especially when one needs to estimate unknown process parameters. In Phase-I control chart implementations, a set of samples that are ideally from an in-control process is formed by iteratively eliminating/retaining potentially out-of-control samples and this is then used in parameter estimation. Nevertheless, sampling variability and samples from an out-of-control process that are not eliminated from a Phase-I data set may have effects on the online process monitoring (Phase II) performance of a control chart due to the control chart design with estimation errors. To provide Phase-I control chart design guidelines, here we investigate in detail the iterative use of the individuals control chart (I-control chart) in Phase I for identifying potentially out-of-control process observations when the initial Phase-I data set consists of contaminated observations, which is then followed by another Phase-II I-control chart designed with the parameter estimates obtained in Phase I. Using the sample size and the width of I-chart?s control limits as design factors in Phase I, process parameters are estimated, and these are used to design an I-chart with 3-sigma control limits for Phase II. In Phase II, expected value (AARL) and standard deviation (SDARL) of the average run lengths are evaluated. Six standard deviation estimators and three different contamination levels are considered. Guidelines for selecting the control limit width, sample size, and standard deviation estimator for the Phase I implementations are provided to yield desirable Phase II AARL performance with a small SDARL. Our contribution is neither in the theory of control charts nor in the individual techniques. Results of this study would be especially useful in automating control chart design processes where there are many control charts to be designed by well-trained operators in statistical process control. With transformations to Industry 4.0, which is a trend for automation and data exchange in manufacturing, utility of procedures for control chart design automation is expected to increase.


Monitoring reliability for a three-parameter Weibull distribution
Sürücü, Barış (Elsevier BV, 2009-02-01)
Control charts are widely used to monitor production processes in the manufacturing industry and are also useful for monitoring reliability. A method to monitor reliability has recently been proposed when the distributions of inter-failure times are exponential and Weibull with known parameters. This method has also been extended to monitor the cumulative time elapsed between a fixed number of failures for the exponential distribution. In this paper, we consider a three-parameter Weibull distribution to mod...
Failure modes and criticality analysis of the preliminary design phase of the Mars Desert Research Station considering human factors
Oğuz, Elif; Clelland, David (Elsevier BV, 2018-10-01)
This work presents an extension to the traditional FMECA (Failure Modes, Effects and Criticality Analysis) method to include the effects of human factors concerning accessibility/repairability, probability of contact and degree of contact. The authors refer to this extension to the traditional FMECA as the Human Design Approach (HDA). All data used in this study was collected during the stay of two of the authors at the Mars Desert Research Station (MDRS) in the Utah desert, USA. The MDRS is a laboratory fo...
Effective use of quality function deployment and Kansei engineering for product planning with sensory customer requirements: A plain yogurt case
Dolgun, Leman Esra; Köksal, Gülser (Informa UK Limited, 2018-01-01)
Product planning, as typically the first phase of quality function deployment, involves identifying customer requirements and translating them into technical requirements. Understanding true customer needs and setting targets for customer and technical requirements can be very difficult especially when sensory product characteristics such as taste, odor, and texture are concerned. In this study, effective approaches are developed and implemented for overcoming these difficulties in a plain yogurt case. A cu...
Energy efficiency of machining operations: A review
Moradnazhad, Mariyeh; ÜNVER, HAKKI ÖZGÜR (SAGE Publications, 2017-09-01)
Manufacturing processes are among the most energy intensive on earth. As negative ecological and economic impacts increase, reducing energy consumption is becoming critically important. In this article, a comprehensive overview of energy-saving strategies and opportunities for increasing energy efficiency in manufacturing operations is presented, with a focus on metal cutting processes. The issues and approaches involved in energy efficiency of machine tools and machining operations are reported in the lite...
Development of a radioecological model for accidental release of radionuclides
Unver, O.; Kocar, C.; Tuncel, G. (Carl Hanser Verlag, 2020-10-01)
A dynamic radioecological model was developed to estimate radiation doses and stochastic health risks due to atmospheric releases in case of a nuclear reactor accident. Activities in some foodstuffs, feedstuffs and grass, and doses from different pathways for age groups and stochastic risks can be calculated by the model. Dynamic features include food harvesting, sowing times, feeding regimes, and the growing up of a person. The model can be coupled to any atmospheric dispersion model which can calculate ra...
Citation Formats
M. Atalay, M. C. TESTİK, S. Duran, and C. H. Weiss, “Guidelines for automating Phase I of control charts by considering effects on Phase-II performance of individuals control chart,” QUALITY ENGINEERING, pp. 223–243, 2019, Accessed: 00, 2020. [Online]. Available: