Figure 1 A Four-stage network series
In the reception unit, we adopt \(v_{i_{1}}\) and \(v_{i_{2}}\) as the
weights on the input variables\(x_{i_{1}j}\left(i_{1}=1,2,\ldots,I_{1}\right)\)and\(x_{i_{2}j}\left(i_{2}=1,2,\ldots,I_{2}\right)\), respectively.
We also denote \(\eta_{d_{1}}\) as the weight associated with the
intermediate measures of the reception unit to the sampling
unit\(z_{d_{1}j}\left(d_{1}=1,2,\ldots,D_{1}\right)\). Finally, let\(u_{r_{1}}\) and \(\ u_{r_{2}}\) denote the weights on the output
variables \(y_{r_{1}j}\left(r_{1}=1,\ldots,R_{1}\right)\) and\(y_{r_{2}j}\left(r_{2}=1,\ldots,R_{2}\right)\) , respectively. The
efficiency of the reception unit is shown by\(\theta_{0}^{\text{Reception}\ \text{unit}}\) . Typically, the
efficiency of the reception unit is defined applying Model 1.