In quality control applications, the quality of a product may effectively be characterized by a relationship between one or more variables that is typically referred to as a profile. In this paper, we propose two control charts, namely the maximum multivariate EWMA (MEWMA) and maximum double MEWMA charts for monitoring the parameters of a multivariate simple linear profile using the individual observations. Moreover, the sensitivities of these control charts are also enhanced with the variable sampling interval feature. The Monte Carlo simulation method is used to compute the zero-state and steady-state run-length characteristics of the proposed charts. Based on detailed run-length comparisons, it is found that the MaxDMEWMA chart is slightly more sensitive than the MaxMEWMA chart. A real dataset is also considered to support the theory.

在质量控制应用中，产品的质量可以有效地通过一个或多个变量之间的关系来表征，这些变量通常被称为概况。在本文中，我们提出了两个控制图，即最大多元 EWMA (MEWMA) 和最大双 MEWMA 图，用于使用单个观测值监测多元简单线性剖面的参数。此外，这些控制图的灵敏度也通过可变采样间隔功能得到增强。Monte Carlo 模拟方法用于计算所提议图表的零状态和稳态运行长度特性。根据详细的游程长度比较，发现 MaxDMEWMA 图比 MaxMEWMA 图略敏感。一个真实的数据集也被认为是支持该理论的。