• 정보처리학회논문지A
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• 제8A권4호
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• pp.345-352
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• 2001

본 논문에서는 리눅스를 기반으로 실시간 음성 처리 VoIP 단말기를 설계 구현한다. 설계 구현하는 하드웨어 시스템은 i486 프로세서를 기반으로 설계되며, 음성 코덱칩을 사용하여 실시간으로 음성 데이터를 처리한다. 또한 실시간 음성 데이터를 관리하고 처리하기 위해 리눅스 기반 실시간 처리 운영 체제인 RTLinux를 포팅하여 실시간 음성처리 모듈을 구현한다. 음성처리에 사용한 음성처리 모듈은 ITU-T 표준 음성 코덱인 G.723.1 사용하여 30ms 내에 24바이트로 인코딩/디코딩된 음성 데이터를 전송하도록 하고, 음성 전달의 QoS를 보장해 주기 위해서 리눅스에 실시간 음성처리 디바이스 드라이버를 설계 구현한다. 설계 구현하는 시스템의 테스트 및 타당성 검증을 위해 음성채팅 응용 프로그램을 단말기에 구현하여 통화품질을 시험한다.

• 대한약침학회지
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• 제17권3호
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• pp.57-61
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• 2014

Objectives: When a person speaks, voice problems usually include pain or discomfort and/or difficulties in terms of the pitch, the loudness and the quality of the voice. When patients with voice problems induced by stroke, Parkinson's disease, and systemic diseases involving the voice are examined, generally, of the Four Diagnoses (四診), a Diagnosis of Hearing can be used in current Korean medicine. The effects of acupuncture and herb medicine on voice problems have been reported for over 20 years. However, when it comes to improvements, objective and subjective evaluation methods need to be explained. Methods: Subjective methods for evaluating voice were studied through a literature search of old medicinal books containing Korean medicine diagnostics, and an objective evaluation method using Praat software is presented. Results: Korean medicine doctors analyze the patient's voice in clinical settings unconsciously on a daily basis. However, most voice diagnoses depend on the doctor's subjective evaluation. Voice qualities can be evaluated by using the Eight Principles (八綱), including Yin-Yang; the Five Elements (Phases); the Grade, Roughness, Breathy, Asthenic, Strained (GRBAS) score, and the Visual Analogue Scale (VAS) as subjective methods, and an acoustic analysis using the Praat program can be used as an objective method. Conclusion: A more complete voice examination can be achieved by using subjective and objective methods at the same time. For an objective explanation and management of patient's voice problems or systemic disorders, an objective method should be used in Korean medicine, which already has many subjective diagnostic methods. More research needs to be conducted, and more clinical evidence needs to be collected in the future.

• The Journal of the Acoustical Society of Korea
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• 제28권2E호
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• pp.35-42
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• 2009

In this paper, we present criteria of objective measurement of speech quality to provide the mobile-VoIP services efficiently over wireless mobile internet. The mobile-VoIP service, which is based on mobility and is error-prone compared to conventional VoIP over wired network, is about to be launched, but there have not been adequate quality indexes and the Quality of Service (QoS) standards for evaluating speech quality of Mobile-VoIP. In addition, there are many factors influencing on the speech quality in packet network of which packet loss contribute directly to the overall voice communication quality. For this reason, we adopt the Gilbert-Elliot Channel Model for modeling packet network based on IP and assess the voice quality through the objective speech method of ITU-T P. 862 PESQ and ITU-T P. 862.1 MOS-LQO under various packet loss rates in the transmission channel environments. Our simulation results address the specific criteria and QoS for the mobile-VoIP services in terms of the various packet loss environments.

• 한국통신학회논문지
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• 제18권12호
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• pp.1841-1854
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• 1993

Ethernet에 음성신호의 전송을 위한 패킷음성 프로토콜을 PC 구현하였다. 구현한 패킷음성 프로토콜은 CCITT의 G.764 패킷음성 프로토콜을 수정하여 사용하였다. 이를 위하여 ethernet을 통한 음성통신을 하기 위한 하드웨어 시스템을 설계하였는데, 전화기 인터페이스부분, 음성처리부분, PC인터페이스부분 및 제어부분으로 나누어진다. 소프트웨어는 OSI 7 계층에 맞추어 설계하였으며 ethernet device driver, 전화기 인터페이스 하드웨어 driver 그리고 패킷음성 프로토콜 처리부분으로 구성되어 있다. 실제 실험결과 ethernet을 통하여 전화를 연결하고 만족한 음성통화를 할 수 있었다.

• 대한후두음성언어의학회지
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• 제22권2호
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• pp.111-114
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• 2011

All singers can often develop voice trouble secondary to vocal abuse and overuse, but it is well known that traditional Korean singer (pansori) develop voice disorders more frequently than western style sunger. While laryngological concern for voice disorders arising in professional singers has received some attention, empirically motivated investigations of the underlying acoustic features of the singing voice have been relatively limited. Since all singers have a good knowledge of the voice and voice training, they would hardly give consent for treatment to a doctor unless he understood their desire to maximize their voice quality. The components of this report are composed of breathing, basic ekement, and vocalization, essencial fact, for getting a perfect voice for pansori. The breathing is based on hypogastric breathing. The main functions of breathing are energy and power of utterence, tempo of rhythm and seperating paragraph and controlling feelings according to dramatic situation. Vocalization is based on general vocalization. Main uses of it are maintaining singer's tone and harmony of cosmetic dual force.

• 한국자동차공학회논문집
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• 제11권2호
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• pp.196-202
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• 2003

The object of this article is to study the plausibility of applying human voice warning system to automobiles. Human voice is considered the best tool for warning system in automobiles. For the purpose of comprehending the specific characteristics of relation between noises and properties of the automobiles indoors and voice warning system researcher performed FRF test in order to examine the characteristics of voice output, and FEM simulation to learn the specific properties of the car indoors. And furthermore, surveyed the quality of voice output, using the written inquiry to examine members. The result of the study shows that it is much possible to apply voice warning system to automobiles.

• 대한후두음성언어의학회지
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• 제22권2호
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• pp.143-150
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• 2011

Background and Objectives : Clinically, as a tool for voice assessment before and after the operation or the voice treatment, acoustic analysis is widely used. However, in clinical situations, acoustic parameters vary according to how the assessment is made. Thus, with voice disease patients as subjects, we are to investigate what influence intensity increase exerts on acoustic parameters and how to reduce variation according to the way of assessing. Material and Method : At the voice clinic of the department of otorhinolaryngology in Gangnam Severance Hospital, with 30 female voice-disease patients (40.6 years old on the average) and 23 male voice-disease patients (40.1 years old on the average) as subjects, using the Dr Speech vocal-assessment program, we statistically tested the significance of the difference in each of acoustic parameters between when the "Ah" vowel is produced with a normal voice and when the "Ah" vowel is produced with a loud voice. Results : Acoustic parameters that showed a statistically significant difference according to intensity increase were Jitter, SD F0, and NNE for females, and Jitter, SD F0, HNR, SNR, and NNE for males. Voice quality estimates showed a statistically significant difference according to intensity increase in female hoarse voice, female breathy voice, and male breathy voice. Conclusion : In this research, acoustic analysis, which is generally used for voice assessment before and after the operation or the voice treatment, showed a tendency that acoustic parameters became better under the influence of intensity increase except for the cases where a voice disease was severe. Thus, to raise the reliability of voice assessment, the range of intensity needs to be set up. This should be the topic for the future research.

• 음성과학
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• 제5권1호
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• pp.121-139
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• 1999

Our experimental subject was a laryngectomee who had undergone total laryngectomy with $PROVOX^{(R)}$ insertion, and learned esophageal speech after the surgery, so he could produce both $PROVOX^{(R)}$ voice and esophageal voice. With this subject's production of $PROVOX^{(R)}$ and esophageal voice, we are to compare the acoustic and aerodynamic characteristics of the two voices, under the same physical conditions of the same person. As a result, the fundamental frequency of esophageal voice was 137.2 Hz, and that of $PROVOX^{(R)}$ was 97.5 Hz. $PROVOX^{(R)}$ voice showed lower jitter, shimmer and NHR than esophageal voice, which means that $PROVOX^{(R)}$ voice showed better voice quality than esophageal voice. In spectrographic analysis, the formation of formants and pseudoformants were more distinct in esophageal voice and several temporal aspects of acoutic features such as VOT and closure duration were more similar with normal voice in $PROVOX^{(R)}$ voice. During the sentence utterance, esophageal voice showed longer pause or silence duration than $PROVOX^{(R)}$ voice. Maximum phonation time and mean flow rate of $PROVOX^{(R)}$ voice were much longer and larger than esophageal voice, but mean and range of sound pressure level, subglottic pressure and voice efficiency were similar in the two voices. Glottal resistance of esophageal voice was much larger than $PROVOX^{(R)}$ voice which showed still larger glottal resistance than normal voice.

• 말소리와 음성과학
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• 제8권2호
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• pp.57-63
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• 2016

Recently, the Lax Vox voice therapy has been used as one of the SOVTE(Semi-Occluded Vocal Tracts Exercise). The purpose of this study was to explore the effect of Lax Vox voice therapy for a patient with Spasmodic dysphonia on voice improvement. One female spasmodic dysphonia patient(age=27) who had been diagnosed by a laryngologist received Lax Vox voice therapy. The Lax Vox protocol was configured as 5 steps (1 warm-up and 4 steps : bubbling without / with phonation/ gliding with phonation/ generalization) in this study. A total of 11 sessions were performed by a certified speech language pathologist. The present study evaluated the acoustic, aerodynamic, auditory perceptual, and patient's self-rating between pre-, mid-, and post- voice therapy. All objective and subjective parameters were improved after voice therapy; Reduced frequency variation, increased maximum phonation time, enlarged voice range, improved 'G' and 'S' in GRBAS & USDRS, and reduced VHI were observed. Especially, decreased $f_0$ and remarkably reduced voice tremor were also demonstrated following Lax Vox voice therapy. Accordingly, Lax Vox voice therapy technique can be useful for improving voice and quality of life in patients with spasmodic dysphonia.

• 대한후두음성언어의학회지
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• 제31권2호
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• pp.71-77
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• 2020

Background and Objectives OperaVOXTM (Oxford Wave Research Ltd.) is a portable voice analysis software package designed for use with iOS devices. As a relatively cheap, portable and easily accessible form of acoustic analysis, OperaVOXTM may be more clinically useful than laboratory-based software in many situations. The aim of this study was to evaluate the agreement between OperaVOXTM and Multi-Dimensional Voice Program (MDVP; Computerized Speech Lab) to assess voice quality before and after laryngeal microsurgery in patient with vocal polyp. Materials and Method Twenty patients who had undergone laryngeal microsurgery for vocal polyp were enrolled in this study. Preoperative and postoperative voices were assessed by acoustic analysis using MDVP and OperaVOXTM. A five-seconds recording of vowel /a/ was used to measure fundamental frequency (F0), jitter, shimmer and noise-to-harmonic ratio (NHR). Results Several acoustic parameters of MDVP and OperaVOXTM related to short-term variability showed significant improvement. While pre-operative value of F0, jitter, shimmer, NHR was 155.75 Hz (male: 125.37 Hz, female: 183.37 Hz), 2.20%, 6.28%, 0.16, post-operative values of these parameter was 164.34 Hz (male: 129.42 Hz, female: 199.26 Hz), 2.15%, 5.18%, 0.14 Hz in MDVP. While pre-operative value of F0, jitter, shimmer, NHR was 168.26 Hz (male: 135.16 Hz, female: 201.37 Hz), 2.27%, 6.95%, 0.26, post-operative values of these parameters was 162.72 Hz (male: 128.267 Hz, female: 197.18 Hz), 1.71%, 5.36%, 0.20 in OperaVOXTM. There was high intersoftware agreement for F0, jitter, shimmer with intraclass correlation coefficient. Conclusion Our results showed that the short-term variability of acoustic parameters in both MDVP and OperaVOXTM were useful for the objective assessment of voice quality in patients who received laryngeal microsurgery. OperaVOXTM is comparable to MDVP and has high intersoftware reliability with MDVP in measuring the F0, jitter, and shimmer