To design a feasible CAPL system for speech rhythm, mora duration factors were statistically investigated using speech recognition methods. Through the experiments, we found that mora duration is considerably affected by vowels rather than consonants, and that vowel durations depend on the manner of articulation of preceding and following consonants. The Hard Template and Soft Template based on these characteristics were very reliable, and played an important role in our CAPL system. Furthermore, the relative rhythm measurement method that we suggested, successfully normalized the variance of speaker's rhythm effectively.
In further work, we need to examine the factors of mora duration using a larger speech database, and evaluate our system for a wider variety of non-native learners of Japanese.
