ABSTRACT
The forward and inverse problems are usually considered in the context of input and output to a system or a process, or in the sense of cause and effect, or stimulus and response. There are three basic components and a number of factors involved in the definition of the forward and inverse problems. We will first consider the three basic components: the system dynamics, the input to the system, X, and the output of the system, Y. This relationship is symbolically shown in Figure 4.1.
