• 대한후두음성언어의학회지
• /
• 제8권1호
• /
• pp.18-26
• /
• 1997

There are two types of phonetic study, acoustic and physiologic, for differentiating the three manner categories of Korean stop consonants. On the physiologic studies, there are endoscopic, electromyographic(EMG), electroglottographic(EGG) and aerodynamic studies. In this study, I tried to investigate general features of Korean stops using EGG study for the open quotient of vocal fold and baseline shift during speech, and aerodynamic characteristics for e subglottal air pressure, air flow and glottal resistance at consonants. On the aerodynamic study, the glottalized and aspirated stops may be characterized by e increasing subglottal pressure comparing with lenis stop at consonants. The airflow is largest in the aspirated stops followed by lenis stops and glottalized. The glottal airway resistance (GAR) showed highest in the glottalized followed by the lenis, but lowest in e aspirated during e production of consonants, and showed highest in e aspirated, but low in the glottalized and lenis during the production of vowel. The glottal resistance at consonant showed significant difference among consonants and significant interaction between subject and types of consonant. The glottal resistance at vowel showed significant difference among consonants, and e interaction occured between subject and types of consonant. The electroglottography(EGG) has been used for investigating e functioning of e vocal folds during its vibration. The EGG should be related to the patterns of the vocal fold vibration during phonation in characterizing the temporal patterns of each vibratory cycle. The purpose of this study is to investigate the dynamic change of EGG waveforms during continuous speech. The dynamic changes of EGG waveforms fir the three-way distinction of Korean stops were characterized that the aspirated stop appears to be characterized by largest open quotient and smallest glottal contact area of the vocal folds in e initial portion of vocal fold vibration ; the lenis stop by moderate open quotient and glottal contact area ; but the glottalized stop by smallest open quotient and largest glottal contact area. There may be close relationship between the OQ(open quotient) in the initial voice onset and the glottal width at the time of consonant production, the larger glottal width just before vocal fold vibration results in the smaller OQ of the vocal fold vibration in the initial voice onset. The EGG changes of baseline shift during continuous speech production were characterized by the different patterns for the three types of Korean consonants. The small and less stiffness change of baseline shift was found for the lenis and the glottalized, and the largest and stiffest change was found for the aspirated. On the baseline shift for the initial voice onset, they showed so similar patterns with for the consonant production, larger changed in the aspirated. for the lenis and the glottalized during the initial voice onset, three subjects showed individual difference each other. I suggest at s characteristics were strongly related with articulatory activity of vocal tract for the production of consonant, especially for the aspirated stop. The suspecting factors to affect EGG waveforms are glottal width, vertical laryngeal movement and the intrapharyngeal pressure to neighboring tissue during connected spech. So the EGG may be an useful method to describe laryngeal activity to classify pulsing conditions of the larynx during speech production, and EGG research can be controls for monitoring the vocal tract articulation, although above factors to affect EGG would have played such a potentially role on vocal fold vibratory behavior obtained using consonant production.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
• /
• pp.9-11
• /
• 2004

The vocal folds play an important role to produce glottal pulse which is an essential factor of phonation. There have been some models which implement the vocal folds' dynamics, such as one-mass model, two-mass model, multi-mass model and ribbon model. Among them, this paper uses nonlinear two-mass model, which is simple structure and produces similarly real glottal pulses and vocal folds' vibration, to realize vocal folds digital model. The pattern of movements in vocal folds will be shown in this paper by using vocal folds digital model. It will be verified how initial position of vocal folds. variation of tension and change of lung pressure influences vibration and glottal pulses.

• 대한의용생체공학회:의공학회지
• /
• 제20권4호
• /
• pp.427-433
• /
• 1999

본 논문에서는 고음질 음성부호화 및 압축, 음성인식 및 합성등의 성능개선에 있어서 중요한 파라메터인 피치정보를 실시간으로 검출하기 위해 연구를 수행하였다. 이를 위하여 변복조 스폿(spot) 전극을 적용한 새로운 EGG(Electroglottograph) 측정 시스템을 개발하여 이용한 안정된 피치검출 알고리즘을 연구하였다. 구체적으로 EGG 신호에 의한 성문 닫힘시점을 실시간으로 결정하여 EGG 기반의 피치궤적 알고리즘을 개발하였고, 음성신호만의 피치궤적 추적기와 성능비교를 수행하여 우월한 성능을 가짐을 보였다. 또한, EGG 신호를 이용한 음성분석을 수행하여 한국인에 있어서 성문의 다양한 진동신호 패턴의 측정 및 분석을 통해 한국인 음원의 모델과 성문신호 패턴에 대한 정량적인 해석을 하였다.

• 대한후두음성언어의학회지
• /
• 제24권1호
• /
• pp.28-32
• /
• 2013

Because the human voice is produced through vibration of the vocal cords during the exhalation of airflow, it is important to observe the vibration pattern of the vocal cords in patients complaining of voice changes. However, it is not easy to observe the actual vibration pattern of the vocal cord because it vibrates so fast that it cannot be observed by the naked eye and it is located deep in the throat. Recently, with advances in instruments, including laryngoscopes and video camera systems, the vibration pattern of the vocal cords can now be observed. However, considering that present video camera systems can detect 30-60 images per second and the vocal cord vibrates at 100-200 and 200-300 times per second in men and women, respectively, it is not possible to record the whole mucosal wave of the vocal cord in real time. To overcome this limitation, a stroboscope, which converts fast movements of the vocal cord into slower images, has been developed. Since then, several instruments were developed to examine vocal vibration pattern. However, each instruments have advantages and disadvantages. Therefore, we should know about these things to apply them in patients with voice problem.

• 대한후두음성언어의학회지
• /
• 제8권1호
• /
• pp.5-11
• /
• 1997

비디오스트로보스코피를 이용한 성대주기(glottal cycle)의 관찰은 질환의 감별 및 치료 전후의 결과를 비교하는데 중요한 정보를 제공하지만, 관찰자의 주관적 견해나 판단능력에 따라 결과의 판독에 많은 영향을 미칠 수 있다. 이에 비디오스트로보스코피 소견의 객관화를 위한 시도가 최근 보고되고 있으나 아직은 그 성과나 결과 등이 참고치로 활용하기에는 부족한 실정이다. 이에 저자들은 정상 성인을 대상으로 발성시의 주파수와 강도의 변화에 따른 glottal cycle의 변화를 정량화 함으로써 추후 연구나 임상적용 등의 기본자료로서 활용하고자 하였다. 정상성인 남녀 각 5명을 대상으로 평상시 대화수준, 고음, 큰 소리의 세 가지 조건에서, 지속적인 /이/ 발성을 후두비디오스트로보스코프를 이용하여 녹화한 뒤, image analysis 프로그램(KSIP, Kay Elemetrics Corp., NJ, USA)을 이용하여 glottal area waveform(GAW)과 amplitude/symmetry waveform(A/SW)을 구하였다. 네 개의 연속적인 glottal cycle의 GAW를 이용하여 peak glottal area, opening ＆ closing phase, open quotient, speed quotient, baseline offset 등의 평균값을 각각의 조건에서 비교하여 보았으며, A/SW를 이용하여 성대의 종축을 기준으로 3등분한 뒤 전, 후, 중간 부위에서 성대운동의 진폭과 그 움직임의 양상을 서로 비교하여 보았다. 발성의 조건에 따라 성대주기와 성대운동의 진폭과 그 양상이 달라짐을 객관적으로 판단할 수 있었으나, 이를 참고치나 기준치로 활용하기 위하여는 더 많은 수의 피검자를 대상으로, 발성의 조건을 체계적으로 변화시킨 연구가 뒷받침되어야 하리라고 사료되었다.

• 음성과학
• /
• 제7권3호
• /
• pp.153-165
• /
• 2000

During the phonation of voiced sounds, instants exist where the glottis is opened or closed, due to the periodic vibration of the vocal cord. When closed, this is called the glottal closure instant(GCI) or epoch.. The correct detection of the GCI is one of the important problems in speech processing for pitch detection, pitch synchronous analysis, and so on. Recently, it has been shown that the local maxima points of the wavelet transformed speech signal correspond to the GCIs of speech signal. In this paper, we investigate the accuracy of Gels estimated from this wavelet transformed speech signal. For this purpose we compare them with the negative peak points of the differentiated EGG signal that represents the actual GCIs of speech signal.

• 대한후두음성언어의학회지
• /
• 제19권1호
• /
• pp.16-20
• /
• 2008

Excising part or all part of a larynx as a cancer operation results in changes that transgress anatomic, physiologic, psychologic, and social priciples. The quality of life of a patient's life after any given cancer surgery usually is regarded as a second-priority consideration after oncologic safety. With laryngeal surgery, excision of malignant disease typically results in change that significantly influence an individual for the duration of his or her life. Nonetheless, with appropriate rehabilitation the surgical side effects can be minimized to allow for an excellent quality of life. Successful conservation surgery for laryngeal cancer requires careful interdependent selection for patients, lesions and procedure. The technical goal is to minimize trauma to uninvolved tissue and to wisely utilized local tissues or tree flap for reconstruction, while insuring for oncologically sound procedure. Rehabilitation should aim to produce a glottal sound source if possible, however voice therapy to promote false vocal fold vibration and arytenoid to epiglottis source of vibration can produce very satisfactory phonatory results.

• 대한후두음성언어의학회지
• /
• 제5권1호
• /
• pp.69-74
• /
• 1994

Thyroplasty type III provides an effective mean of shortening the vocal fold. It is used primarily fer lowering vocal pitch. The indications for this surgery are the male patients with too high a vocal pitch of long duration which has proven resistant to voice therapy and a type of dysphonia characterized by high pitch and a breathy voice, in which the laryngeal findings include a very narrow glottal chink and a small amplitude of vibration, suggesting a stiff vocal cord. In this study, we have experienced two cases of high pitched voice, one is mutational falsetto and other is high pitched, breathy voice with stiff vocal fold. The results were satisfactorily successful with type III thyroplasty. So we report the cases of type III thyroplasty in patients of dysphonia with high pitched voice.

• 대한기관식도과학회:학술대회논문집
• /
• 대한기관식도과학회 1993년도 제27차 학술대회 초록집
• /
• pp.71-71
• /
• 1993

이중음성이란 성대진동이 정상이 아닌 유사주기성에 의해 양측 성대진동의 위상차이때문에 발생되는 소리로서 대표적으로 양측성대의 긴장불균형(tension imbalance)시와 양측성대 사이의 높이차이(level difference)시에 발성직전의 성문열림의 정도에 따라 성대진동의 주기가 서로 다르기 때문에 이중음성이 발생한다고 한다. 그러나 실제 이러한 현상은 일측성대 마비환자뿐 아니라 성대의 점막부위에 증가된 질량효과에 의해 이중음성이 나타날 수 있는데 대표적으로 성대내 낭종이라 하겠다. 본 연구에서는 청각적으로 이중음성을 나타낸 일측성대마비, 성대내낭종 및 성대육아종 등 수술을 받았던 19례를 대상으로 음향학적 분석중 음성파형을 이용한 분석을 한 결과 유사주기성 음성파형에 대한 특징들중에서 파형수, peak변이도, 잡음의 정도등이 각질환에 따라 다른 양상을 보여 이중음성의 발생기전이 질환에 따라 다름을 알 수 있었다.

• 한국정보처리학회논문지
• /
• 제5권10호
• /
• pp.2725-2736
• /
• 1998

본 논문은 WRLS-VFF-VT 알고리듬을 이용한 새로운 피치 검색 방법론을 제안하도록 한다. 제안된 알고리듬에서는 VFF(가변 망각 인자)를 사용하여 유성음에서의 주 여기 펄스 시점과 관련된 성문 폐쇄 점을 확인한다. 또한 본 논문은 VFF 기반 알고리듬과 함께 기존의 EGG 와 LP-Error 방법을 이용한 피치 검색 알고리듬에서 가변 한계 값을 이용 수정된 알고리듬을 제안한다. 제안된 알고리듬들은 주기와 주기 근간에서 강인한 피치 측정 능력과 준 주기 및 비 주기성 음성 신호에서도 우수한 피치 검색 기능을 가지고 있음을 알 수 있다. 제안된 알고리듬의 우수성을 입증하기 위해 실제 사람의 자연스러운 음성 및 사람의 비정상 상태 음성에서 준 주기 및 비 주기성 음성 진동 패턴을 확인하고 검출하는 성능 측정을 통하여 표준 SIFT 알고리듬과 비교 평가하였다.