...system

Our research of the CALL on L2 pronunciation has been named CAPL (Computer-Assisted Pronunciation Learning) different from other general CALL systems)

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...characters

In this thesis, for convenience we use this notation instead of the IPA (International Phonetic Alphabet) characters.

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...reached

This general method is called Estimation Maximization (EM).

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...Algorithm

It is also known as the Baum-Welch Algorithm.

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...score

In general, it represents the matching degree, i.e., the larger it is, the closer the speech is to the standard phoneme models.

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...mora

Japanese speech rhythm, i.e., a unit of metric timing usually equal to, but sometimes smaller than, a syllable

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...transfer

Generally, non-native learners tend to transfer the peculiar features of pitch contours of their own native language to a second language. This phenomenon is known as prosodic transfer and presents a difficulty in a second language learning.

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...hypothesis

The critical period hypothesis

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...teacher

It is as if learners hear L2 through a filter, which is the sound system of L1.

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...pairs

In the description of L2 consonants and vowels, the sounds that contrast are principally introduced; that is, those sounds that can be substituted for one another in words to cause a change in meaning. In general, they are termed minimal pairs.

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...frequency

For uniformity, pitch is sometimes designated 108#108.

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...mora

A unit of metric timing usually equal to, but sometimes smaller than, a syllable.

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...direction

We need to investigate it using more context patterns.

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