ABSTRACT
A modern plant-wide automation and information technology system should comprise the following subsystems or layers: regular regulatory control (RRC), advanced regulatory control (ARC), advanced process control (APC) and optimization, statistical quality/process control (SQC/SPC), scheduling, and enterprise resource planning (ERP). These subsystems can be automated by using instrumentation and computers with appropriate software. The relationship between them can be illustrated in the pyramid graph in Figure 26.1. Each layer relies on the underlying layer(s) to be effective. For instance, an APC and optimization system relies on good regulatory control of the process.
