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References                         14:

                                   Training Set













                     Input      Hetero-association    Output
                                 Neural Network




                  Fig. 2.57. A block box representation of a heteroassociation NN.




       about 4 stored letters, whereas the I PA model is quite stable for all 26 letters.
       Even for a 10% input noise level, it can retrieve effectively up to 12 stored
       letters. As for noiseless input, the IPA model can, in fact, produce correct
       results for all 26 stored letters.
          Furthermore, pattern translation can also be accomplished using a hetero-
       association IPA neural network. Notice that by using similar logic operations
       among input-output (translation) patterns, a heteroassociative IWM can be
       constructed. An example of the heteroassociation NN is shown in Fig. 2.57,
       The objective is to translate a set of English alphabets to a set of Chinese
       characters. We see that if A is presented to the heteroassociation NN, a
       corresponding Chinese character is converged at the output end.



       REFERENCES


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        3. L. j. Cutrona et al., On the Application of Coherent Optical Processing Techniques to Synthetic
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           Commun., 17, 59 (1976).
        5. C. F. Hester and D. Casacent, Multivariant Technique for Multiclass Pattern Recognition, Appl.
           Opt., 19, 1758 (1980).
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