• Phonetics and Speech Sciences
• /
• v.6 no.2
• /
• pp.29-34
• /
• 2014

In the Vector Taylor Series (VTS)-based noisy speech recognition methods, Hidden Markov Models (HMM) are usually trained with clean speech. However, better performance is expected by training the HMM with noisy speech. In a previous study, we could find that Minimum Mean Square Error (MMSE) estimation of the training noisy speech in the log-spectrum domain produce improved recognition results, but since the proposed algorithm was done in the log-spectrum domain, it could not be used for the HMM adaptation. In this paper, we modify the previous algorithm to derive a novel mathematical relation between test and training noisy speech in the cepstrum domain and the mean and covariance of the Multi-condition TRaining (MTR) trained noisy speech HMM are adapted. In the noisy speech recognition experiments on the Aurora 2 database, the proposed method produced 10.6% of relative improvement in Word Error Rates (WERs) over the MTR method while the previous MMSE estimation of the training noisy speech produced 4.3% of relative improvement, which shows the superiority of the proposed method.

• Journal of Korean language education
• /
• v.29 no.3
• /
• pp.345-363
• /
• 2018

The purpose of this study is to compare the speech rate of advanced Korean(L2) learners and Korean native speakers in spontaneous utterances. Specifically, the current study investigated the difference of the two groups' speech pattern according to utterance length. Eight advanced Korean(L2) learners and eight Korean native speakers participated in this study. The data were collected by recording their conversation and physical measurements (speaking rate, articulatory rates, pause and several types of speech disfluency) were taken on extracted 120 utterances from 12 out of the 16 participants. The findings show that advanced Korean learners' speech pattern is similar to that of Koreans in the short-length utterance. However, in the long-length utterance, two groups show different speech patterns; while the articulatory rate of Korean native speakers increased in the long-length utterance, that of Korean learners decreased. This suggests that the frequency of speech disfluency factors might affect this result.

• Journal of Korean Public Health Nursing
• /
• v.20 no.2
• /
• pp.174-182
• /
• 2006

Purpose: The purpose of this study was to test the effect of lavender fragrance on speech anxiety and public speech behavior of nursing students. Method: The subjects were 89 students in the nursing department of "K" college. We administered vaporizers containing lavender to the experimental group to measure the degree of speech anxiety and public speech behavior at pre-treatment and post-treatment. Results: The difference of variance in speech anxiety between the experimental and control groups was not significant (p=.477). However, the speech anxiety of the experimental group from pretest to post-test was significantly increased (p=.061). In addition, public speech behavior in the experimental group showed greater improvement than that in the control group (p=.000). Conclusion: This study has provided preliminary evidence that lavender fragrance may improve public speech behavior.

• Phonetics and Speech Sciences
• /
• v.7 no.2
• /
• pp.95-102
• /
• 2015

The purpose of this paper is to extract the vowel formants of the ten adult male speakers in their twenties and thirties from the Korean Corpus of Spontaneous Speech [4], also known as the Seoul corpus, and to analyze them by comparing to earlier works on the Buckeye Corpus of Conversational Speech [1] in terms of the various linguistic factors that are expected to affect the formant distribution. The vowels extracted from the Korean corpus were also compared to those of the read Korean. The results showed that the distribution of the vowel formants from the Korean corpus was very different from that of read Korean speech. The comparison with English corpus and read English speech showed similar patterns. The factors affecting the Korean vowel formants were the interviewer sex, the location of the target vowel or the syllable containing it with respect to the phrasal word or utterance and the speech rate of the surrounding words.

• Speech Sciences
• /
• v.13 no.1
• /
• pp.95-105
• /
• 2006

The primary goal of therapeutic intervention in dysarthric speakers is to increase the speech intelligibility. Decision of critical features to increase the intelligibility is very important in speech therapy. The purpose of this study is to know the effects of pitch increasing training (PIT) on speech of a subject with Parkinson's disease (PD). The PIT program is focused on increasing pitch while a vowel is sustained with the same loudness. The loudness level is somewhat higher than that of the habitual loudness. A 67-year-old female with PD participated in the study. Speech therapy was conducted for 4 sessions (200 minutes) for one week. Before and after the treatment, acoustic, perceptual and speech naturalness evaluation was peformed for data analysis. Speech and voice satisfaction index (SVSI) was obtained after the treatment. Results showed Improvements in voice quality and speech naturalness. In addition, the patient's satisfaction ratings (SVSI) indicated a positive relationship between improved speech production and their (the patient and care-givers) satisfaction.

• Phonetics and Speech Sciences
• /
• v.5 no.4
• /
• pp.17-24
• /
• 2013

This study is aimed at finding out different types of speech characteristics categorized based on voice rehabilitation techniques used on twenty-six patients (all-male) with total or partial laryngectomees. The speech intelligibility of standard esophageal (SE), tracheoesophageal speech (TE), and electriclarynx (EL) was measured by using the CSL and eleven listeners were instructed to rate the speech on a 5-point scale. The vowel space parameters such as vowel space, VAI, FCR, and F2 ratio were measured by averaging 5 repeats of each vowel (/a/, /e/, /i/, /u/) and the results were put into the parameter formula. The results showed significant statistical differences in speech intelligibility and vowel space between SE and TE. The speech intelligibility and vowel space of TE were higher than those of SE or EL and there was a high correlation between speech intelligibility and some parameters (vowel space, VAI, F2 ratio). The results also showed that TE's speech characteristics were most similar to normal groups comparing with SE and EL, but still very deviant in laryngeal speech. This was due to insufficient airflow intake into the esophagus when producing sounds, and because articulation movement was carried out differently among groups. Therefore, these findings will contribute to establishing a baseline related to speech characteristics in voice rehabilitation for patients with alaryngeal speech.

• Speech Sciences
• /
• v.10 no.1
• /
• pp.85-94
• /
• 2003

In this paper an algorithm to reduce the size of Text-to-Speech database is proposed. The algorithm is based on the characteristics of Korean phonemic units. From the initial database, a reduced phoneme unit set is induced by articulatory similarity of concatenating phonemes. Speech data is read by one female announcer for 1000 phonetically balanced sentences. All the recorded speech is then segmented by phoneticians. Total size of the original speech data is about 640 MB including laryngograph signal. To synthesize wave, RE-PSOLA (Residual-Excited Pitch Synchronous Overlap and Add Method) was used. The voice quality of synthesized speech was compared with original speech in terms of spectrographic informations and objective tests. The quality of the synthesized speech is not much degraded when the size of synthesis DB was reduced from 320 MB to 82 MB.

• The Transactions of the Korea Information Processing Society
• /
• v.4 no.6
• /
• pp.1531-1540
• /
• 1997

In this paper, we presents automatic Korean continuous speech recognizer which is improved by the speech rate estimation and the compensation methods. Automatic continuous speech recognition is significantly more difficult than isolated word recognition because of coarticulatory effects and variations in speech rate. In order to recognize continuous speech, modeling methods of coarticulatory effects and variations in speech rate are needed. In this paper, the speech rate is measured by change of format, and the compensation is peformed by extracting relatively many feature vectors in fast speech. Coarticulatory effects are modeled by defining 514 Korean diphone set, and ETRI's 445 word DB is used for training speech material. With combining above methods, we implement automatic Korean continuous speech recognizer, which shows improved recognition rate, based on DHMM(Discrete Hidden Markov Model).

• Korean Journal of Audiology
• /
• v.24 no.4
• /
• pp.167-173
• /
• 2020

Background and Objectives: Top-down restoration of distorted speech, tapped as phonemic restoration of speech in noise, maybe a useful tool to understand robustness of perception in adverse listening situations. However, the relationship between phonemic restoration and speech perception in noise is not empirically clear. Subjects and Methods: 20 adults (40-55 years) with normal audiometric findings were part of the study. Sentence perception in noise performance was studied with various signal-to-noise ratios (SNRs) to estimate the SNR with 50% score. Performance was also measured for sentences interrupted with silence and for those interrupted by speech noise at -10, -5, 0, and 5 dB SNRs. The performance score in the noise interruption condition was subtracted by quiet interruption condition to determine the phonemic restoration magnitude. Results: Fairly robust improvements in speech intelligibility was found when the sentences were interrupted with speech noise instead of silence. Improvement with increasing noise levels was non-monotonic and reached a maximum at -10 dB SNR. Significant correlation between speech perception in noise performance and phonemic restoration of sentences interrupted with -10 dB SNR speech noise was found. Conclusions: It is possible that perception of speech in noise is associated with top-down processing of speech, tapped as phonemic restoration of interrupted speech. More research with a larger sample size is indicated since the restoration is affected by the type of speech material and noise used, age, working memory, and linguistic proficiency, and has a large individual variability.

• Speech Sciences
• /
• v.12 no.2
• /
• pp.17-28
• /
• 2005

This paper argues that news speech entails a distinct intonational pattern from natural speech, effectively reflecting that it primarily focuses on providing new information. We conducted a phonetic experiment to compare the tonal contours between news speech and natural speech, examining the distributions of pitch accents and the overall pitch ranges. We utilized 70 American Press (AP) radio news utterances and 70 natural utterances extracted from TV dramas. Results show that news speech involves 3.38 H*'s (including L+H* and !H*) within an intonational phrase (IP) or intermediate phrase (ip) whereas natural speech, 1.8 in average. The number of IP/ip's per sentence is 3 in news speech, which is shown in the highest rate of 32.07% of the news speech, but it is merely 1, taking up the highest 41.42% in natural speech. Next, declination tends to be prevented in news speech, and the pitch range is much greater in news speech than in natural speech. Finally, a secondary stress syllable is comparatively frequently given a pitch accent in news speech, explicitly distinct from natural speech. These results can be interpreted as stating that news has the particular purpose of providing new information; every content word tends to be given a H* or its related pitch accent like L+H* or !H* because news speech assumes that every word conveys new information. This definitely brings about more IP/ip's per sentence due to a human physiological constraint; that is, more H*'s will cause more respiratory breaks. Also, greater pitch ranges and pitch accents imposed on secondary stress may be attributed to exaggerating new information.