This papeer proposes a general approach of the multivariate expontially weighted moving average(MEWMA) chart, in which the smoothing matrix has full elements instead of only diagonal elements. The average run length (ARL) properties of this scheme are examined for a diverse set of quality control environments and the information to design the chhart is provied. Performance of the scheme is measured by estmating ARL and compared to those of two group cumulative sum (CUSUM) chats. The comparison resullts show that the MEWMA chart can improve its ARL performance in detecting a small shifts out-of-control in the start-up stage, the general MEWMA chart of a full smoothing matrix appears to offer an exceptional protection aginst departures from control in the process mean

An important objective of pull-based production control is to achieve synchronized and smooth production flow in a multi-stage system that is subject to uncertainty. To our knowledge, previous research has not generated a performance measure that captures this objective of pull-based probased production control system. This performance material with respect to the instant when the operation is required. We examine the issue of asynchronous waste in a two-stage kanban control system.