The manufacturing industry is one of the earliest
advocates and wide-spread users of computer based
control systems. However, the application of control
system and technology has progress only slightly
beyond applying variations in the classical
"proportional-integral-derivative"(PID) controller online
control systems.manufacturing industry are
still typically plagued by both technical and operational
difficulties from the process. The processes to be controlled
are generally nonlinear,time-dependent,
interactive, and history dependent. The detailed
theoretical processes themselves are fiequiently not well
understood. Theoretical models, when they exist, are
usually static, are vcry complex, involve large numbers
of variabes, require extensive computational power,
and require information which is often either not
available or practical at the plant.