SOM (self-organizing map) implemented by wafer scale integration-its self-organizing behavior under defects

Self-Organizing Map (SOM) implemented by Wafer Scale Integration (WSI) will provide us very-high-speed and desk-top-size hardware for practical applications. Thanks to a synergistic effect of all neurons for ordering, the SOM-WSI is expected to reach the desired global-ordering-state permitting defective neurons in it. In this paper, we mathematically evaluated the robustness of the SOM against defective neurons. Furthermore, experiments on the defective SOM were carried out and the results agreed well with the theoretical ones. From these evaluations, high fault-tolerance of the present neuro-computer has been shown. The results and the criteria derived from the evaluations can be used for the SOM-WSI design in the next step.