The purpose of this study was to develop a Korean assessment model for the patients with voice disorders. Interviews were conducted with 4 voice therapists and the results were analyzed by using a qualitative, constant-comparative design. According to the three themes emerged from the qualitative analysis, 10 subthemes were derived. The three main themes were 1) consideration on the disordered voice, 2) status quo of instrumental and perceptual evaluation, and 3) suggestions for the other voice therapists. The 10 subthemes can be summarized as the following: 1) judgment centering on the patients, 2) increase of the reliability of instrumental and perceptual evaluation, 3) voice therapists' positive participation in the assessment procedure of voice disorder.

This study examined the aerodynamic functions (mean airflow rate MFR, subglottal pressure Psub) and closed quotients (CQs) in the fixed pitch (C3, E3, G3, C4) with the variable loudness (70 and 80 dB) as well as in the fixed loudness at 70 dB and 80 dB with the variable pitch (C3, E3, G3, C4) in five classic male singers (Baritone). Results showed that MFR significantly increased at C3, E3, and G3 and Psub significantly increased at C4 when the loudness increased from 70 to 80 dB. At 70 dB, MFR and Psub significantly increased and CQ significantly decreased when the pitch increased from C3 to C4. At 80 dB, MFR significantly decreased when the pitch increased from C3 to G3. However, Psub showed the significant decrease with the pitch increased at 80 dB. In conclusion, as the loudness increases, the aerodynamic loss is getting higher and vocal efficiency becomes lower at low pitch than at higher pitch. At a low loudness level, the main mechanism to control loudness is the amount of medial compression of the vocal folds rather than the aerodynamic function. In addition, the aerodynamic function and medial compression of the vocal folds have a significant role in increasing the loudness level.

The aim of this study is to analyze the correlation between current intensity and amplitude of stimulus artifact on the cochlear implantee, and to find out basic information to check the device failure. Subjects were a prelingual child and 3 postlingual adults with more than severe hearing losses. The charge-balanced biphasic pulses were presented at stimulus rates of 11 pulses per second, each pulse width of $25{\mu}s$ with monopolar mode(MP1+2). Current intensities were delivered at 27.5, 33.7, 41.3, 50.5, 61.9, $75.8{\mu}A$. Stimulus artifacts were recorded by evoked potential system. This procedure was performed just before the initial stimulation, and then, the amplitude of stimulus artifacts were compared with each current intensity. The amplitude of stimulus artifacts was increased significantly according to the current intensity (p<0.01). The results suggest that the change of the amplitude of stimulus artifact can be used as a good cue to check the device failure in the cochlear implantee.

The purpose of this study was to observe the effect of eating a raw egg by professional or nonprofessional voice users on their voice quality and the duration of the effect. 20 professional voice users and 20 nonprofessional voice users participated in the experiment and they had gone through stroboscopy to have no vocal or laryngeal diseases. The voice exam was performed three times: before eating a raw egg (1st period), right after eating it (2nd period), and 10 minutes later (3rd period). By using Multi-dimensional Voice Program which is a software of Computerized Speech Lab 4500 as a voice analysis instrument, the authors checked the F0, Jitter, Shimmer, Noise to harmonic ratio (NHR), and Voice Range Profile (VRP). Results showed as follows: Firstly, vocal hygiene was good in 57.5% of the total subjects and was poor in 42.5%. 40% of professional voice users and 75% of nonprofessional voice users hand good quality. 77.5% of the total subjects had the vocal fatigue while 22.5% of the subjects did not. 95% of the professional voice users and 60% of nonprofessional voice users complained the vocal fatigue. 60% of the total subjects reported a subjective vocal symptom. 65.0% professional voice users and 70.0% of nonprofessional voice users reported a voice symptom. From the results above, we suggest that eating a raw egg may lead to imporve voice quality of the professional voice users.

Laryngeal DDK involve with the rate, pattern, and regularity (periodicity) in opening and closing of vocal fold. This study was aimed at investigating the characteristics of laryngeal DDK between nonfluent and fluent speakers. One with an ataxic dysarthria (with cerebellar lesion) and the other with stuttering, and 13 normal speakers were evaluated. L-DDK were analyzed with MSP (motor speech profile, CSL 4400). Measures of DDK included: DDKavr, DDKcvp, DDKjit, DDKavp. An ataxic dysarthric speaker and a stutterer showed more reduced rate and aperiodic L-DDK (both adductory and abductory movement) than normal speakers. But the average L-DDK period (ms) in adductory movement in a speaker with stuttering showed more decreased than the other. Results from this study are preliminary. Nonetheless, results of L-DDK produced by nonfluent speakers suggested the possibility to have relation with slow rate of phonatory initiation and connected speech. In the future, perceptual studies are needed in conjuction with acoustic and speech production.

The severe-profound hearing impaired children have various disorders in everday communication due to the lack of hearing feedback. Especially, their speech produced unstable voice, omission and distortion of articulation, pitch break, cul-de-sac voice, and so on so that they were difficult to accurately deliver an intended message. This study attempts to analyze the acoustic characteristics of 4 vowel sounds produced by 35 severe-profound hearing impaired children using CSL(Computerized Speech Lab, Model 4300b). The formant data were obtained from the spectrogram and analyzed data by 12 formant filter and auto-correlation among the formants. Results showed that the hearing impaired children's formant values came out very high. They produced the vowels at the mode of hypertension with unstable voice. In order to improve their speech, they would need some adequate auditory feedback.

The aim of this study was to examine the articulation characteristics of preschool children in the bilingual or monolingual environment. Subjects included 23 children of 4 to 6 years old in the bilingual environment, and 19 children of monolingual environment. Their speech was evaluated in terms of articulation correctness and intelligibility by the author and a speech therapist. Results showed as the following: First, there were some significant differences between bilingual and monolingual children in the percentage of consonants correctly articulated. But there was no significant difference between their language environment or ages in the percentage of vowels correctly articulated. Second, there were some significant differences between the bilingual and monolingual children in the intelligibility of word articulation. Also, there were some significant differences between the two language groups in the sentence intelligibility. There was a high positive correlation between the word and sentence intelligibility.

The purpose of this paper is to develop a model enabling to predict the prosody of Korean text-to-speech synthesis using the CART and SKES algorithms. CART prefers a prediction variable in many instances. Therefore, a partition method by F-Test was applied to CART which had reduced the number of instances by grouping phonemes. Furthermore, the quality of the text-to-speech synthesis was evaluated after applying the SKES algorithm to the same data size. For the evaluation, MOS tests were performed on 30 men and women in their twenties. Results showed that the synthesized speech was improved in a more clear and natural manner by applying the SKES algorithm.

The performance of speaker identifier is severely degraded in noisy environments. A study suggested the concept of observation membership for enhancing performances of speaker identifier with noisy speech [1]. The method scaled observation probabilities of input speech by observation identification values decided by SNR. In the paper [1], the authors suggested heuristic parameter values for membership function. In this paper we attempt to apply particle swarm optimization (PSO) for obtaining the optimal parameters for speaker identification in noisy environments. With the speaker identification experiments using the ETRI database we prove that the optimization approach can yield better performance than using only the original membership function.

There have been many research efforts to improve the performance of the speech recognizer in noisy conditions. Among them, the model compensation method and the speech enhancement approach have been used widely. In this paper, we propose to combine the two different approaches to further enhance the recognition rates in the noisy speech recognition. For the speech enhancement, the minimum mean square error-short time spectral amplitude (MMSE-STSA) has been adopted and the parallel model combination (PMC) and Jacobian adaptation (JA) have been used as the model compensation approaches. From the experimental results, we could find that the hybrid approach that applies the model compensation methods to the enhanced speech produce better results than just using only one of the two approaches.

Feature vectors of speech are generally extracted from whole frequency domain. The inherent character of a speaker is located in the low band or high band frequency. However, if the speech is corrupted by narrowband noise with concentrated energy, speaker verification performance is reduced as the individual characteristic is removed. In this paper, we propose a PCA Covariance Model based on the multiband to extract the robust feature vectors against the narrowband noise. First, we divide the overall frequency band into several subbands. Second, the correlation of feature vectors extracted independently from each subband is removed by PCA. The distance obtained from each subband has different distribution. To normalize against the different distribution, we moved the value into the normalized distribution through the mapping function. Finally, the represented value applying the weighting function is used for speaker verification. In the experiments, the proposed method shows better performance of the speaker verification and reduces the computation.

Old Korean regulated poems have a typical prosodic structure characterized by a pitch contour. This work applies Jun's finding in Seoul Korean(Jun 1993, 2000, 2005) to old Korean regulated poems, and reports some other significant phonetic characteristics, arguing that old Korean regulated poems have a regular rhythm based on the pitch contour implementing the typically hierarchical prosodic structure. The major prosodic units defined are a foot, a phrase, and a line. Next, this work proposes pitch contour characterizing prominence in a unit, boundary tones, and pauses at the boundary position, as the basic and significant cues of rhythm of a Korean poem. Specifically, some significant characteristics are discussed as follows: first, the tonal pattern of a foot is HL, starting high and ending low; second, the lowering boundary tones of HL% and L% are perceived at the end of a phrase and a line; and finally, a gradient degree of pause is observed at each unit-final position.