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6.2 SEMIEMPIRICAL MODELING OF LONGITUDINAL SHORT-PERIOD MOTION FOR A MANEUVERABLE AIRCRAFT  203



















                          FIGURE 6.2 Coverage diagrams for the training set section (α, ˙α) for (A) doublet and (B) polyharmonic signals with an
                          equal number (1000) of training examples.




























                          FIGURE 6.3 The process of polyharmonic signal generation (see also Fig. 6.4).


                          sides, we can also compare the final distribu-  monic signal concerning the training set infor-
                          tion of training examples with the distribution  mativeness.
                          given by one of the widely used test signals,  As in the example considered in Section 5.5,
                          namely, the doublet. It is evident that the dou-  we will use the standard deviation of additive
                          blet is substantially inferior to the polyharmonic  noise acting on the output of the system as the
                          signal regarding informativeness of the corre-  target value of the simulation error.
                          sponding training data set. Similarly, we can  In order to utilize the Matlab Neural Network
                          see that all the other types of control signals  Toolbox, we represent the ANN model in the
                          listed above are also inferior to the polyhar-  form of an LDDN. Neural network learning is
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