Results 11 to 20 of about 173,902 (219)
Mathematics, 2020 Shewhart control charts with estimated control limits are widely used in practice. However, the estimated control limits are often affected by phase-I estimation errors.
Ishaq Adeyanju Raji +4 more
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Enhanced fault detection models with real-life applications
AIMS Mathematics, 2023 Nonconforming events are rare in high-quality processes, and the time between events (TBE) may follow a skewed distribution, such as the gamma distribution.
Showkat Ahmad Lone +5 more
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Unit Interval Time and Magnitude Monitoring Using Beta and Unit Gamma Distributions
Journal of Mathematics, 2022 Quick detection of an assignable cause is necessary for process accuracy with respect to the specifications. The aim of this study is to monitor the time and magnitude processes based on unit-interval data.
Muhammad Farhan Akram +3 more
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A STUDY OF THE MEDIAN RUN LENGTH (MRL) PERFORMANCE OF THE EWMA t CHART FOR THE MEAN
South African Journal of Industrial Engineering, 2012 The exponentially weighted moving average (EWMA) chart is effective in detecting small shifts. However, the EWMA chart is not robust enough to prevent errors in estimating the process standard deviation or a changing standard deviation.
Chin, W. S., Khoo, M. B. C.
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IEEE Access, 2022 In statistical process monitoring, it is often assumed that the sequential observations generated by processes are independent and identically distributed (iid).
Yi Li, Tahir Munir, Xuelong Hu
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Enhanced cumulative sum charts for monitoring process dispersion. [PDF]
PLoS ONE, 2015 The cumulative sum (CUSUM) control chart is widely used in industry for the detection of small and moderate shifts in process location and dispersion. For efficient monitoring of process variability, we present several CUSUM control charts for monitoring
Mu'azu Ramat Abujiya +2 more
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Nonparametric Double EWMA Control Chart for Process Monitoring
Revista Colombiana de Estadística, 2016 In monitoring process parameters, we assume normality of the quality characteristic of interest, which is an ideal assumption. In many practical situations, we may not know the distributional behavior of the data, and hence, the need arises use ...
MUHAMMAD RIAZ, SADDAM AKBER ABBASI
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Connection Science, 2022 The mixed control chart is proposed to improve detection performance with fewer process shifts. In this study, we proposed the modified exponentially weighted moving average - moving average control chart (MMEM), a new mixed control chart for observing ...
Khanittha Talordphop +2 more
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Mathematics, 2022 Shewhart charts are the most commonly utilised control charts for process monitoring in industries with the assumption that the underlying distribution of the quality characteristic is normal. However, this assumption may not always hold true in practice.
Jing Jia Zhou +4 more
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Scientific Reports, 2023 In this study, we introduce an Adaptive Exponentially Weighted Moving based Coefficient of Variation (AEWMCV) control chart, designed to address situations where the process mean fluctuates over time and the standard deviation of the process changes ...
Afshan Riaz +5 more
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