Variable sampling interval exponentially weighted moving average median chart with estimated process parameters

MBC Khoo, S Saha, HC Lee… - Quality and Reliability …, 2019 - Wiley Online Library
The variable sampling interval exponentially weighted moving average median chart with
estimated process parameters is proposed. The charting statistic, optimal design …

Conditional analysis of Phase II exponential chart for monitoring times to an event

N Kumar - Quality Technology & Quantitative Management, 2020 - Taylor & Francis
It is now well known that the error in estimating parameter (s) adversely affects the
performance of control charts. The charts with estimated control limits are usually assessed …

A variable sample size run sum coefficient of variation chart

WC Yeong, YY Tan, SL Lim, KW Khaw… - Quality and Reliability …, 2022 - Wiley Online Library
A run sum chart with variable sample size (VSS) to detect shifts in the coefficient of variation
(γ) is proposed. The run sum γ chart divides the chart into different regions with distinct …

Simultaneous monitoring of origin and scale of a shifted exponential process with unknown and estimated parameters

ZL Chong, A Mukherjee… - Quality and Reliability …, 2021 - Wiley Online Library
The distribution of consumer lifetimes, high‐voltage of current in semiconductor transistors,
and the risk associated with monitoring health care often come with a threshold. A two …

Optimal design of the side‐sensitive modified group runs (SSMGR) chart when process parameters are estimated

ZL Chong, MBC Khoo, WL Teoh… - Quality and …, 2019 - Wiley Online Library
A side‐sensitive modified group runs (SSMGR) chart is commonly examined under the
assumption of known process parameters (denoted as Case‐K). However, in practical …

Variable sampling interval run sum median charts with known and estimated process parameters

S Saha, MBC Khoo, PS Ng, ZL Chong - Computers & Industrial Engineering, 2019 - Elsevier
The variable sampling interval run sum (VSI RS) median chart with known and estimated
process parameters are proposed for efficiently monitoring the process mean. The …

Two CUSUM schemes for simultaneous monitoring of unknown parameters of a shifted exponential process and its application in monitoring of call durations in …

S Saha, A Mukherjee, MBC Khoo - Quality Technology & …, 2022 - Taylor & Francis
Telemarketing is crucial in sales promotion for products and services, and it is very popular
in businesses and industries. The call duration during Telemarketing is an important feature …

Optimal design of the side sensitive group runs double sampling (SSGRDS) X¯ scheme with estimated process parameters

ZL Chong, WC Yeong, KW Khaw… - Transactions of the …, 2024 - journals.sagepub.com
The side sensitive group runs double sampling (SSGRDS) X¯ scheme is previously studied
under the known process parameters (Case-K) assumption. As the process parameters are …

New run sum t charts with variable sampling intervals for process mean

FN Mim, MBC Khoo, S Saha, A Haq - Communications in Statistics …, 2022 - Taylor & Francis
The t chart is commonly used as an alternative to the Shewhart mean chart when the
process standard deviation is not known in advance. In this paper, we develop variable …

A study on the performances of the run sum X̄ chart under the gamma process

K Le Goh, WL Teoh, ZL Chong, KL Ong… - ITM Web of …, 2024 - researchportal.hw.ac.uk
The run sum (RS) X̄ chart is known as a simple and powerful tool for monitoring the mean
of a process. Most developments of the RS X̄ chart assume that the underlying process …