The performance of the cochlear implant (CI) deteriorates rapidly in the presence of background noise, and the conventional spectral subtraction speech enhancement method used in the CI can not remove the non-stationary noise well. In order to improve the audio perception ability of the CI users, an improved spectral subtraction method is proposed, which divides the power spectrum of the noisy speech according to the Bark bands and estimates the noise by using the minima controlled recursive averaging method in every individual band when the speech frame is present. Then the adaptive spectral subtraction parameters are used in the algorithm. The proposed spectral subtraction method has been applied in CI, and the simulation result shows that the proposed algorithm may extract the speech features more correctly and the CI synthesized sound is of higher quality.
Algorithms ; Audiometry, Speech ; Cochlear Implants ; Humans ; Sound Spectrography ; Speech Perception

The detection and analysis of bowel sounds are of importance to the diagnosis and treatment of gastrointestinal diseases. In this paper are summarized the recent advances in the detection and analysis as well as in the application of new techniques to monitoring bowel sounds. Several methods, including spectrum analysis, adaptive filtering, wavelet transform, principal component analysis, and artificial neutral network are mainly introduced. All of them are promising for feature extraction and automatic classification of bowel sounds.
Algorithms ; Gastrointestinal Motility ; physiology ; Humans ; Neural Networks (Computer) ; Principal Component Analysis ; Signal Processing, Computer-Assisted ; Sound ; Sound Spectrography ; instrumentation ; methods

In analyzing the postoperative results or evaluating the velopharyngeal incompetence after palatoplasty, speech evaluation is the inevitable factor. However, a standardized method for evaluating the speech problem in Korean cleft palate patients has not been available until now. So, the authors tried to establish a method of speech evaluation which is simple, economic and applicable to young patients, and to make a scoring method of the speech results in cleft palate patients based on the 'hypernasality diagnosing tool for cleft palate patient (OK Ran Jung)' which is commonly used by domestic speech therapists. The authors adopted the 'hypernasality diagnosing tool for cleft palate patients (OK Ran Jung)' male and female of children and adults, each consisting of 10 patients and make them speak according to the items about hypernasality and misarticulation evaluation, and record the results. We also calcuted the degree of the formants of the vowels (/a/, /o/, /u/)using sound spectrography. We examined the interjudge and intrajudge reliance of speech evaluation among the 10 inverstigators, revised the evaluation tool, devised the scoring method according to the above results, and compared the scoring results with those of sound spectrography to prove the reliance of our speech evaluation tool. With the scoring method, the authors could estimate the degree of hypemasality and misarticulation in cleft palate patients with evidence of reliability based on point-to-point agreement in two items. In comparing the results of our scoring method with the formant of vowels using sound spectrography, staistical significance existed except /u/F2 and that meant that our scoring method was reliable. We suggest that this simple, economic and reliable method of speech evaluation in cleft palate patients can create the basis for speech evaluation in patients of cleft palate and velopharyngeal incompetence under circumstances in which the results of various speech treatments are evaluated in comparison to various methods of speech evaluation.
Adult ; Articulation Disorders ; Child ; Cleft Palate* ; Female ; Humans ; Male ; Research Design ; Sound Spectrography ; Velopharyngeal Insufficiency

BACKGROUND AND OBJECTIVES: Laser-assisted uvulopalatoplasty is well established and relatively successful operation in the treatment of snoring and obstructive sleep apnea (OSA). But, there have been no reports about snoring sound of patients who had been performed LAUP. This study was performed to evaluate the results of LAUP analysing preoperative snoring sounds. MATERIALS AND METHODS: There were 38 patients who were diagnosed as OSA by polysomnography and had been performed LAUP between Mar, 1998 and July, 2002. Preoperative and postoperative snoring sounds were recorded during sleep and we performed an acoustic analysis using spectrogram (SPG), which was classified. And postoperative subjective satisfaction of bed time partner was compared in each type and the degree of satisfaction was measured by VAS (visual analogue scale) score. According to previous study, types of spectrogram of snoring sounds were classified as palatal, tongue base and mixed. RESULTS: In postoperative analysis, snoring loudness was most decreased in palatal type, and snoring pitch was only increased in tongue base type. The average satisfaction of bed time partner was highest at palatal type and lowest at tongue base type. CONCLUSION: Preoperative analysis of snoring sounds can aid the prediction of the loudness and pitch of snoring sounds and the subjective satisfaction of patients after LAUP.
Acoustics ; Humans ; Laser Therapy ; Palate ; Polysomnography ; Sleep Apnea, Obstructive ; Snoring* ; Sound Spectrography ; Tongue

OBJECTIVE: To study the relationship between the first formant (F1) and jaw, the second formant (F2) and tongue and the third formant (F3) and lip. Fine articulation of jaw, lips, tongue by measured formant of different single-vowel, in order to explore clinical implications of F1, F2 and F3. METHOD: Measure 30 hearing normal men's F1, F2, F3 of /a/, /i/, /e/, /u/ and /ü/. The study compared F1 of /a/, /i/, /e/ to find the relation ship between F1 and jaw movement by one-way anova, compared F2 of /a/, /i/, /e/, /u/ to find the relationship between F2 and four tongue movements, and compared F2 and F3 of /i/, /ü/ to find the relationship between F2, F3 and lip movement by paired-samples t test. RESULT: There was significant difference among F1 of /a/, /i/, /e/. F2 and F3 of /i/, /ü/ were also significantly different (P<0.01); F2 of /a/, /i/, /u/ that expresses tongue articulation movement exists significant difference (P<0.01), but both F2(a) and F2(e) did not differ significantly by multiple compare means. There were extremely significant differences (P<0.01) among other three positions of tongue. CONCLUSION F1 can reflect different positions of jaw. F2 and F3 can reflect the position of lip and tongue. F2 can reflect different locations of tongue.
Adolescent ; Adult ; Humans ; Male ; Sound Spectrography ; Speech Acoustics ; Speech Production Measurement ; Vocal Cords ; physiology ; Young Adult

Distortion of vowels in dysarthria associated with amyotrophic lateral sclerosis can be detected at the perceptual, physiological, and acoustical levels of analysis. Sound spectrography was used to analyse the formants of vowels which reflect position and space of articulatory organs. We analyse status and progression of dysarthria in 54 year old women with amyotrophic lateral sclerosis using sound spectrography. Target formant frequencies were measured from select words containing the vowels /a/, /e/, /i/, /o/, /u/. Results revealed that dysarthric patient exhibited smaller vowel space areas and less systematic changes in vowel spaces for pronouncing different vowels in comparison with normal control. Changes of vowel formants in sound spectrographic analysis reflected progression of dysarthric symptom in this patient. We conclude that acoustic analysis of vowels using sound spectrography is a useful tool to visualize and quantitatively analyse the severity and progression of dysarthria due to paralytic articulatory organ.
Acoustics ; Amyotrophic Lateral Sclerosis ; Bulbar Palsy, Progressive* ; Dysarthria ; Female ; Humans ; Middle Aged ; Sound Spectrography*

OBJECTIVETo study the characteristic of joint sounds from temporomandibular joint (TMJ) without symptom during mandible movement.

METHODSJoint sounds of 42 asymptomatic TMJ were recorded and analyzed with K6-I system during mandible movement, the waveform, frequency range, peak frequency and amplitude of joint sounds electrosonogram were studied.

RESULTSJoint sounds were recorded in 25 joints of the 42 joints, 4 kinds of joint sounds were found according to the waveform, frequency range, peak frequency and amplitude of the electrosonography.

CONCLUSIONSJoint sounds can be recorded in asymptomatic TMJ during mandible movement, 4 kinds of joints sounds were found according to the electrosonographic characteristics.

Adult ; Female ; Humans ; Male ; Signal Processing, Computer-Assisted ; Sound ; Sound Spectrography ; Temporomandibular Joint ; physiopathology ; Temporomandibular Joint Disorders ; classification ; diagnosis ; physiopathology ; Young Adult

Cough is one of the most common symptoms of many respiratory diseases; the characteristics of intensity and frequency of cough sound offer important clinical messages. When using these messages, we have need to differentiate the cough sound from the other sounds such as speech voice, throat clearing sound and nose clearing sound. In this paper, based on Empirical Mode Decomposition (EMD) and Hidden Markov Model (HMM), we proposed a novel method to analyze and detect cough sound. Employing the property of adaptive dyadic filter banks of EMD, we gained the mean energy distribution in the frequency domain of the signals in order to analyze the statistical characteristics of cough sound and of other sounds not accompanied by cough, and then we found the optimal characteristics for the recognition using HMM. The experiments on clinical date showed that this optimal characteristic method effectively improved the detective rate of cough sound.
Cough ; diagnosis ; physiopathology ; Diagnosis, Computer-Assisted ; methods ; Humans ; Markov Chains ; Monitoring, Physiologic ; methods ; Pattern Recognition, Automated ; methods ; Sound ; Sound Spectrography ; methods

To enhance speech recognition in noise, as well as tone recognition, we presented a new kind of speech coding strategy, called one-octave wavelet transform zero-crossing stimulation (WTZS), for cochlear implants based on amplitude and frequency modulation. We selected 15 volunteers with normal hearing ability to carry out hearing simulation experiments by picking up the amplitude (amplitude modulation, AM), zero-crossings (frequency modulation, FM) and gradient parameters from processed speech signal in the domain of one-octave wavelet transform to synthesize the stimulating pulstile series. The experimental results demonstrated that the phonetic recognition in quiet surroundings with amplitude modulation only strategy (CIS) is similar to that of amplitude and frequency modulations strategies (FAME and WTZS), while the tone perception of CIS is inferior to that of FAME and WTZS strategies. However, in noisy environment, the phonetic recognition, tone perception, as well as sentence recognition of WTZS strategy are better than those of CIS and FAME strategies. WTZS strategy, utilizing amplitude (AM), zero-crossings (FM) and gradient parameters to synthesize stimulus, can enhance the phonetic and tonal language recognition in noise environment effectively, and could be used in cochlear implant system for speech processor design after arithmetic optimization.
Cochlear Implants ; Humans ; Language ; Prosthesis Design ; Signal Processing, Computer-Assisted ; Sound Spectrography ; methods ; Speech Acoustics ; Speech Perception ; physiology

OBJECTIVETo explore the acoustic characteristics of adductor spasmodic dysphonia.

METHODSThe acoustic characteristics, including acoustic signal of recorded voice, three-dimensional sonogram patterns and subjective assessment of voice, between 10 patients (7 women, 3 men) with adductor spasmodic dysphonia and 10 healthy volunteers (5 women, 5 men), were compared.

RESULTSThe main clinical manifestation of adductor spasmodic dysphonia included the disorders of sound quality, rhyme and fluency. It demonstrated the tension dysphonia when reading, acoustic jitter, momentary fluctuation of frequency and volume, voice squeezing, interruption, voice prolongation, and losing normal chime. Among 10 patients, there were 1 mild dysphonia (abnormal syllable number < 25%), 6 moderate dysphonia (abnormal syllable number 25%-49%), 1 severe dysphonia (abnormal syllable number 50%-74%) and 2 extremely severe dysphonia (abnormal syllable number > or = 75%). The average reading time in 10 patients was 49 s, with reading time extension and aphasia area interruption in acoustic signals, whereas the average reading time in health control group was 30 s, without voice interruption. The aphasia ratio averaged 42%. The respective symptom syllable in different patients demonstrated in the three-dimensional sonogram. There were voice onset time prolongation, irregular, interrupted and even absent vowel formants. The consonant of symptom syllables displayed absence or prolongation of friction murmur in the block-friction murmur occasionally.

CONCLUSIONSThe acoustic characteristics of adductor spasmodic dysphonia is the disorders of sound quality, rhyme and fluency. The three-dimensional sonogram of the symptom syllables show distinctive changes of proportional vowels or consonant phonemes.

Adult ; Case-Control Studies ; Dysphonia ; diagnosis ; physiopathology ; Female ; Humans ; Male ; Middle Aged ; Sound Spectrography ; Speech Acoustics ; Tics ; diagnosis ; physiopathology ; Voice Quality ; Young Adult