• The Journal of the Acoustical Society of Korea
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• v.14 no.4
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• pp.38-45
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• 1995

In this paper a way to improve the performance of the long term prediction is proposed, which adopts the Multi-band Excitation (MBE) method in addition to the Code-Excited Linear Prediction (CELP) method at low bit rates below 4.8 kbps. In the proposed method, the multiband long term prediction is performed on the periodic components which still remain after the long term prediction of the conventional CELP method. At this point, the whole frequency region is divided into subbands whose size is equal to the spacing between the harmonics of the fundamental frequency, and the periodic multiband excitation signals. are represented as the sum of sine waves approximately as large as the spectrum of the excitation signals, so that the actual characteristics of the excitation signals can be better taken into account. To evaluate the performance of the proposed method, computer simulation is performed at 4.8 kbps. The 4.8 kbps DoD CELP and the 4.4 kbps IMBE were chosen as the reference vocoders for the speech quality measure. The result of the perceptual speech quality measure showed that the performance of the proposed method is better than that of the 4.8 kbps DoD CELP vocoder, and similar to that of the 4.4 kbps IMBE vocoder.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.5
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• pp.409-416
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• 2005

Purpose of study: The temporomandibular joint (TMJ) occupies a key functional role in mastication and contributes to normal deglutition, speech as well as cosmesis. When a large amount of mandible including the condyle head is resected, it is very difficult to reconstruct it as a functional unit. In this retrospective study, we present the functional, radiographic and cosmetic results of reconstructed temporomandibular joint using free fibular flap. Patients and Methods: Total 12 patients (M:F = 6:6) who underwent condylar reconstruction with the fibular flap were interviewed and examined by radiographs and Bio-PAK$^{(R)}$. Mean follow up periods was $47.7{\pm}20.0$ months and the average age was $38.7{\pm}15.3$ years. Remodeling of condyle and function of TMJ were evaluated and facial contour was judged subjectively. Results: All flaps were viable and no immediate postoperative complication had happened. One patient showed decreased mouth opening, so interpositional gap arthroplasty was performed. The resorption rates of reconstructed fibular were minimal and the condyle heads were changed into domeshaped neocondyle after 2 years. All patients had normal diet and no speech difficulty was reported. Nine patients were satisfied with their facial contour but three patients complained about the depression of cheek. Conclusion: The reconstruction of TMJ with free fibular flap was reliable methods and very effective means of restoring mandibular function. The functional and morphologic results were excellent and showed little complications.

• The Journal of the Acoustical Society of Korea
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• v.21 no.5
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• pp.471-477
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• 2002

Recently, lip-reading has been studied actively as an auxiliary method of automatic speech recognition(ASR) in noisy environments. However, almost of research results were obtained based on the database constructed in indoor condition. So, we dont know how developed lip-reading algorithms are robust to dynamic variation of image. Currently we have developed a lip-reading system based on image-transform based algorithm. This system recognize 22 words and this word recognizer achieves word recognition of up to 53.54%. In this paper we present how stable the lip-reading system is in environmental variance and what the main variant factors are about dropping off in word-recognition performance. For studying lip-reading robustness we consider spatial valiance (translation, rotation, scaling) and illumination variance. Two kinds of test data are used. One Is the simulated lip image database and the other is real dynamic database captured in car environment. As a result of our experiment, we show that the spatial variance is one of degradations factors of lip reading performance. But the most important factor of degradation is not the spatial variance. The illumination variances make severe reduction of recognition rates as much as 70%. In conclusion, robust lip reading algorithms against illumination variances should be developed for using lip reading as a complementary method of ASR.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.16 no.2
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• pp.171-178
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• 1994

Cystic hygroma remains a complex entity in terms of its development and management. Most recently, cystic hygroma has been categorized as part of a larger spectrum that include lymphangioma. The majorities of lymhangioma occur in the head and neck as cystic hygromas with the posterior cervical region as the most common site. Cystic hygromas usually present in infancy or early childhood as compressible masses that may rapidly and intermittently enlarge. While they may arise in any anatomic location, hygromas of the head and neck are especially difficult and speech pathology. Since as airway obstruction, feeding difficulties, and speech pathology. Since its original description, there have been many attepmts at treatment modalities : surgical excision remains the treatment of choice. Complete extirpation of these lesions is often impossible, and recurrence rates are accordingly high. This is report of a case bout 5-year-old female patient with cystic hygroma, resulted in facial asymmetry and swallowing difficulty, in left submandibular area. We obtained the successful functional and esthetic results by simple surgical excision of tumor mass. Therefore, we represents the case with literatural reviews.

• 재활복지
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• v.22 no.4
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• pp.103-121
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• 2018

For knowing the effects of aging on conversational skills in daily communication, this paper studied for the conversational turn-taking skills, working memory and naming ability on healthy elderly adults over 65 ages. 85 elderly adults participated in this study, which divided into four groups by ages. Speech samples were collected in natural conversation. Memorization of numbers, mental calculation, repetition of words were administered for working memory test. K-BNT was used for the naming ability. One-way ANOVA analysis was used for the comparison of conversational turn-taking skills among four groups. We analyzed the correlation between conversational skills, working memory and naming ability. The results were as follows: first, there were a significant difference in conversational turn-taking skills by age, but not by gender. There was a significant difference in 'Turn-Taking Frequency' and 'Total Utterance Frequency' among four groups. The same results were shown in the scores of females within three groups(exclude groups over 85D)(p<.01). Second, there was a significant correlation between 'rates of maintenance' and 'naming ability'. In addition, it was found that the naming test predicted 'rates of maintenance' skills. The results of this study suggest that word-retrieval ability will be helpful to enhance functional communication skills in aging old adults.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.224-231
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• 2019

The current paper was conducted to unravel the influence of affect induction as a background emotion in the process of cognitive task to judge the degree of sequence in groups with or without anxiety symptoms. Four types of affect induction and two sequential task types were used as within-subject variables, and two types of college students groups classified under the Beck Anxiety Inventory (BAI) as a between-subject variable were selected to determine reaction times involving sequential judgment among the lexical relevance information. DmDx5 was used to present a series of stimuli and elicit a response from subjects. Repeated measured ANOVA analyses revealed that reaction times and error rates were significantly larger with anxiety participants compared to the normal group regardless of affect and task types. Within-subject variable effects found that specific affect type (sorrow condition) and number-related task type showed a more rapid response compared to other affect types and magnitude-related task type, respectively. In sum, these findings confirmed the difference in tendency with reaction time and error rates that varied as a function of accompanying affect types as well as anxiety level and task types suggesting the that underlying background affect plays a major role in processing affect-cognitive association tasks.

• The Journal of the Acoustical Society of Korea
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• v.14 no.1E
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• pp.22-29
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• 1995

Code excited Linear Prediction(CELP) vocoder exhibits good performance at data rates below 4.8 kbps. The major drawback of CELP type coders is their large amount of computation. In this paper, we propose a new pitch searching method that preseves the quality of the CELP vodocer reducing computational complexity. The basic idea is that pregrasps preliminary pitches about signal and performs pitch search only about the preliminary pitches. Applying the proposed method to the CELP vocoder, we can reduce complexity about 90% in th pitch search.

• Journal of Internet Computing and Services
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• v.21 no.4
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• pp.35-41
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• 2020

This paper proposes an algorithm to improve the compression performance of the adaptive multi-rate (AMR) speech coding using the context tree weighting (CTW) method. AMR is the voice encoding standard adopted by IMT-2000, and supports 8 transmission rates from 4.75 kbit/s to 12.2 kbit/s to cope with changes in the channel condition. CTW as a kind of the arithmetic coding, uses a variable-order Markov model. Considering that CTW operates bit by bit, we propose an algorithm that re-orders AMR data and compresses them with CTW. To verify the validity of the proposed algorithm, an experiment is conducted to compare the proposed algorithm with existing compression methods including ZIP in terms of compression ratio. Experimental results indicate that the average additional compression rate in AMR data is about 3.21% with ZIP and about 9.10% with the proposed algorithm. Thus our algorithm improves the compression performance of AMR data by about 5.89%.

• The Journal of the Korea Contents Association
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• v.11 no.10
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• pp.380-387
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• 2011

This study was to investigate the effects of music-combined respiration and oral motor training on the voice of healthy elderly. 27 women attending a senior center in Seoul participated and were randomly assigned to the experimental (n = 16) and the control group (n = 11). Subjects attended music program(25 minutes per session) once a week for 4 weeks. For both groups, Fundamental Frequency (F0), Maximum Phonation Time (MPT) and Sequential Motion Rates (SMR) were measured using the Praat speech analysis program before and after the training. The results showed statistical significance in scores of intensity, F0, MPT, and SMR in the experimental group while only intensity was statistically significant in the control group. Considering that, the increasing life expectancy and growing number of older adults, their quality of life has been important. So this study suggests that the respiration and oral motor training would be effectively incorporated into training and services for this population.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.7
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• pp.1370-1376
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• 2012

This paper proposes a gender recognition algorithm which classifies a male or female speaker. In this paper, characteristic vectors for the male and female speaker are analyzed, and recognition experiments for the proposed gender recognition by a neural network are performed using these characteristic vectors for the male and female. Input characteristic vectors of the proposed neural network are 10 LPC (Linear Predictive Coding) cepstrum coefficients, 12 LPC cepstrum coefficients, 12 FFT (Fast Fourier Transform) cepstrum coefficients and 1 RMS (Root Mean Square), and 12 LPC cepstrum coefficients and 8 FFT spectrum. The proposed neural network trained by 20-20-2 network are especially used in this experiment, using 12 LPC cepstrum coefficients and 8 FFT spectrum. From the experiment results, the average recognition rates obtained by the gender recognition algorithm is 99.8% for the male speaker and 96.5% for the female speaker.