ABSTRACT
In this chapter the issues related to the upgrade of instrumentation to improve the accuracy of the estimation of key variables are discussed and specific models are presented.
As pressure mounts to obtain more reliable and accurate estimates of variables and parameters, the use of data reconciliation techniques is the first level of response. In many cases, the existing redundancy is not enough to guarantee the level of accuracy required. Thus, one is faced with an existing set of sensors, to which an addition of new sensors will provide the desired accuracy.
