High intellectual, high flexible automatic manufacturing system based on low volume production is the trend in the future, but the traditional control charts whose control limits are based on at least 20～25 subgroups...High intellectual, high flexible automatic manufacturing system based on low volume production is the trend in the future, but the traditional control charts whose control limits are based on at least 20～25 subgroups of five observations each are not suitable in this environment. The paper presents variance control chart used in small batch production in which there are not sufficient observations. The control limits are set reliably without restriction of the number of samples.展开更多
In this article, we propose two control charts namely, the “Multivariate Group Runs’ (MV-GR-M)” and the “Multivariate Modified Group Runs’ (MV-MGR-M)” control charts, based on the multivariate normal processes, ...In this article, we propose two control charts namely, the “Multivariate Group Runs’ (MV-GR-M)” and the “Multivariate Modified Group Runs’ (MV-MGR-M)” control charts, based on the multivariate normal processes, for monitoring the process mean vector. Methods to obtain the design parameters and operations of these control charts are discussed. Performances of the proposed charts are compared with some existing control charts. It is verified that, the proposed charts give a significant reduction in the out-of-control “Average Time to Signal” (ATS) in the zero state, as well in the steady state compared to the Hotelling’s T2 and the synthetic T2 control charts.展开更多
文摘High intellectual, high flexible automatic manufacturing system based on low volume production is the trend in the future, but the traditional control charts whose control limits are based on at least 20～25 subgroups of five observations each are not suitable in this environment. The paper presents variance control chart used in small batch production in which there are not sufficient observations. The control limits are set reliably without restriction of the number of samples.
文摘In this article, we propose two control charts namely, the “Multivariate Group Runs’ (MV-GR-M)” and the “Multivariate Modified Group Runs’ (MV-MGR-M)” control charts, based on the multivariate normal processes, for monitoring the process mean vector. Methods to obtain the design parameters and operations of these control charts are discussed. Performances of the proposed charts are compared with some existing control charts. It is verified that, the proposed charts give a significant reduction in the out-of-control “Average Time to Signal” (ATS) in the zero state, as well in the steady state compared to the Hotelling’s T2 and the synthetic T2 control charts.
