Nonlinear Profile Monitoring for Oven-Temperature Data

摘要

Problem: The monitoring of a key input, temperature, in a manufacturing process produces large amounts of data. It is difficult to determine an appropriate control-chart methodology that allows the chart user to determine when there are problems with this step of the manufacturing process. Current approaches for process monitoring involve the output data gathered after the process has been completed. It would be preferable to establish process monitoring on the process inputs. However, this is challenging when there is a large amount of process input data. Current phase I monitoring of the process inputs involve the use of individual control charts on some selected data from the temperature profiles that represent some features determined based on expert judgment. This approach does not use all the data nor does it take into account the potential correlation that exists among the selected data.