An economically designed Sequential Probability Ratio Test control chart for short-run production

Control charts for flexible and multi-variety production systems

“…Even Gu et al (2013), who proposed an Average Control Chart for small batches and short-runs with self-start characteristic did not consider batches of size one. Authors as Li et al (2014), Tercero-Gomez et al (2014) and Zhang et al (2014) also have recently proposed control charts for short-runs. Unfortunately, these charts are not able to deal with multi-variety systems in one single chart.…”

“…It is also important to consider multiple setup area open to new studies. The approach presented by Zhang et al (2014) is an interesting way to continue studies in univariate control charts applied to multi-variety production systems. Multivariate strategies still need development in this kind of application.…”

“…Fan and You (2009) reported the major problems of implementing SPC in scenarios subject to high flexibility and small production lots: (i) the assumption of uncorrelated data is usually not satisfied; (ii) the production of a significant amount of items finishes before large enough samples are collected to ensure accurate estimation of process control limits; and (iii) modern processes tend to operate in continuous flow with quality control sometimes being lagged. Short production runs rarely offer enough data for estimation purposes Snoussi, El Ghourabi, & Limam, 2005;Zhang, Su, Li, & Wang, 2014). Many advanced statistical techniques were proposed and adapted for identify special causes of variation in the manufacturing process (Bettayeb, Bassetto, & Sahnoun, 2014;Chiu, 2015;Del Castillo & Montgomery, 1995;Graham, Mukherjee, & Chakraborti, 2012;Guh, 2010;Semino, Morretta, & Scali, 1996;Shi, Ceglarek, & Ding, 2000;Raza, Prasad, & Li, 2015;Yang, Yu, Cheng, & Xie, 2015;Zeifman & Ingman, 2003).…”

“…This model and the proposed algorithm can be applied in job shop manufacturing systems and intend to prevent excessive scrap production. Zhang et al (2014) proposed an sequential probability ratio test control chart for short-run production from an economic perspective. This study do not consider assumptions violation or even known changes in the process due a high flexibility environment, but it shows an alternative way to investigate quality monitoring in MC environments.…”

Economic modelling for statistical process control subject to a general quality deterioration

“…Accordingly, the problem of control chart design for finite or short production runs has attracted more and more attention -see, e.g. Makis (2009), Li andPu (2012), Li et al (2014), Nenes et al (2014), Zhang et al (2014) and Castagliola et al (2015). In this paper, we develop a flexible economic model with regard to the production lot, suitable for both short-run and long-run productions, and we pay particular attention to the design issues associated with charts for finite production runs.…”