6. The data process unit according to claim 5 , wherein the mathematical distance calculating means calculates the mathematical distance using one of Euclidean distance determined based on a mean vector of normal distributions of the pattern models generated using the HMMs, Euclidean distance determined based on a mean vector of normal distributions of the pattern models normalized by the standard deviation of the normal distributions of the pattern models, and Bhattacharrya distance determined based on normal distributions of the pattern models.
5. The data process unit according to any of claims 1 to 3 , wherein the pattern models are generated using HMMs (Hidden Markov Models).