I. Introduction
The general objective of a production process can be regarded as the maximization of the revenue of the activity. In order to address this objective, a series of concerns naturally arises: first, the characteristics of the good to be produced must be defined; second, the values of the process parameters that allow to achieve these characteristics must be determined, and, finally, the process must be run assuring that these parameters and, more importantly, the final product characteristics, remain at their prescribed values.