(A) study on speech intelligebility testing with Korean consonants

Abstract

The purposes of this thesis are to propose test materials for scoring the intelligibility of speech in Korean and to evaluate the relationship between the background noise and the intelligibility of speech by using the propose the test materials. For the construction of the materials, first, eight distinctive features are classified by the place and manner of articulation. Second, the frequency of occurrence of phonemes is considered. The format used is of the form consonantvowel-consonant(CVC). An experiment was performed to determine the effect of the signal-to-noise ratio (S/N ratio) with reliability when administered to nine adult males in graduate school (KAIST). The level of noise is manipulated to provide S/N ratio of -2, 0, 6 and 9dB relative to the level of speech. As the result of an experiment, it is shown that only S/N ratio of three factors (speaker, listener and S/N ratio) effects on the intelligibility of speech. The result suggests that it is effective especially in evaluating the performance level of a military communication system. Analysis of the responses to individual elemente is discussed for enhancing the intelligibility.