One dimensional ring type growing SOM with asymmetric neighborhood function and its application to a hand shape instruction learning system

An asymmetric neighborhood function was proposed by Aoki and Aoyagi to instead of symmetric neighborhood function in conventional Kohonen's self-organizing map (SOM) to avoid topological twist of the order of units during training process. Meanwhile, a one dimensional ring type growing SOM was proposed by Ohta and Saito to reduce the unnecessary increasing of units of conventional 2-D growing SOM. In this paper, we adopt the asymmetric neighborhood to a parameterless growing SOM (PL-G-SOM) proposed by Kuremoto et al. to construct a novel SOM: One dimensional ring type growing SOM using asymmetric neighborhood function (One-D-R-A-G-SOM). The proposed SOM is applied to instruction recognition and learning system with input of hand shapes for human-machine-interaction (HMI), especially for users of speech handicapped people. The effectiveness of the proposed method was confirmed by the experiments comparing with systems using conventional SOMs.