• :

    There is a need for some industrial processes such as agricultural, aquacultural and chemical for identifying if their processes are performing out of control at an early stage to then investigate and take corrective actions. Most of the current profile monitoring procedures use a Hotelling’s T2 type of chart that requires the entire profile data. We propose to use a Shewhart control chart based on a Gaussian process (GP) model with heteroscedasticity
    that takes into account replications to evaluate each profile as it evolves with respect to a mean function. The advantage of the GP model with replications is that it captures both the between and within profile correlation. Another advantage is that this chart does not need to wait until the profile ends to evaluate whether its behavior is abnormal. Our results indicate that our proposed chart is effective especially relative to the current T2 procedures under this model.

  • : Quevedo, A. Valeria; Vining, G. Geoff
  • : Virginia Tech; Universidad de Piura
  • : A. Valeria Quevedo
  • : quality
  • : intermediate
  • : anavq@vt.edu
  • : 5404497076
Monitoring within and between non-linear profiles using a Gaussian process model with heteroscedasticity