Combining off-line and on-line information in process study using the self-organizing map (SOM)

This paper presents how process control problems can be studied and solved by combining offline and online information. Offline information is accurate and versatile, it is used to define the problem. Online information describes the state of the process in real time. The online variables containing information of the offline defined problem are selected using a variable selection algorithm. These variables are used to create an online observer of the problem. This observer can be used to solve process control problems. The main algorithms used in this paper are the variable selection technique and the self-organizing map (SOM). The methodology is illustrated using the case of the concentrator of the Outokumpu Hitura mine.