• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.9
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• pp.850-857
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• 2011

Generally, sound-absorbing materials in vehicles are used for giving the comfort to passengers by reducing noise while driving. Materials of which targets are light weight, high performance, eco friendliness and recycling have been developed recently. In this study, sound-absorbing materials using PET(polyethylene terephthalate) hollow fibers to achieve the light weight and the high sound absorption performance are developed, and then evaluated to meet a requirement for the automotive components. The test results show that the acoustic performances of developed products having new fiber structure are better than those of the conventional product.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.1185-1191
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• 2001

This paper discusses an experimental method for measuring the insertion loss (IL) performance of multi-layered insulations that are used in vehicles. Instead of two adjacent reverberation chambers which are generally used to measure the transmission loss (TL) of the large sound isolation materials, air-borne sound insulation tester was utilized to determine the IL and articulation index (AI) of standardized insulation materials. In comparison to reverberation chamber method, air-borne sound insulation tester method is more space-saving, more time-saving and more simple to the automotive acoustics. From the empirical results, it is found that the performances of insulation materials are closely connected with density of polyurethane foam, thickness of heavy layer, thickness of polyurethane foam, and application ratio to panel area.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.4
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• pp.318-327
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• 2012

The operating sound radiated from a laser printer includes tonal noise components caused by the rotating mechanical parts such as gear, shaft, motor, fan, etc. The negative effects of the tonal noise components need to be considered in the process of developing a sound quality index for the quantitative evaluation of the emotional satisfaction in terms of psycho-acoustics. However, in a previous paper, it was confirmed that the Aures tonality did not have enough correlation with the results of jury evaluation. The sound quality index based on loudness, articulation index, fluctuation strength has a little problem in considering the effects of rotating mechanical parts on the sound quality. In this paper, to solve the tonality evaluation problem, the calculation algorithm of Aures tonality was investigated in detail to find the cause of decreasing the correlation. The new tonality evaluation model was proposed by modifying and optimizing the masking effect, loudness ratio, and shape of weighting curve based on the basic algorithm of Aures tonality, and applied to two kinds of operating sound groups in order to verify the usefulness of proposed model. As a result, it is confirmed that the proposed tonality evaluation model has enough correlation and usefulness for expressing the tonalness in the operating sounds of laser printers. In the following paper, this results will be used to model the sound quality index as the input data by using the classification algorithm.

• 재활복지
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• v.21 no.2
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• pp.217-231
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• 2017

We have to consider two parts of the evaluation and treatment for the patients with head and neck burns. The primary consideration is swallowing function for nutrition supply for them and the next is speech function for efficient communication and aesthetic impression of them. The purpose of this study is to summarize the preliminary questions of Communication Screening Protocols which can help understand comprehensively on swallowing disorder, motor speech disorder and voice disorder of patients with head and neck burns. We divided the evaluation into 4 evaluation areas including 'oral mechanism', 'respiration/voice', 'articulation', and 'swallowing' by referring to overseas studies dealing with various communication disorders caused by burns, and prepared the final questionnaires by conducting the content validity verification by five expert (speech & language pathologist). The range of Content Validity Index was shown relatively appropriate with .50~.84. There was a conflict of opinions in experts whether the items in the areas of respiration/voice and swallowing may be appropriate, whereas there was no different view of the oral mechanism and articulation area. Through the different characteristics of communication difficulties of patients with head and neck burns, we expect it will be modified appropriately according to the patients through evaluation of burn patients by type and severity.

• Korean Journal of Applied Biomechanics
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• v.25 no.4
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• pp.453-463
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• 2015

Objective : The purpose of this study was to investigate the effects of the Probody Massage Program on the physical characteristics, gross motor function and ROM (Range Of Motion) of children with cerebral palsy. Method : The subjects of this study were two children who have been diagnosed with first grade cerebral palsy that utilized T development support center located in B Metropolitan city for 8 weeks, twice a week, to carry out the Probody Massage Program for 30 minutes. Physiological reactions (height, weight, BMI, blood pressure (an index of inflammation), pulse rate) and large operating functions (sitting, crawling and the joints' range of motion as an angle of the shoulders' upper limb articulation) were measured pretest, after 4 weeks, and after 8 weeks. Results : The Probody Massage Program showed positive changes in physical characteristics (blood pressure, sitting, and crawling), gross motor function (upper limb shoulder movement), joint range of motion, height, body weight, metabolic activation and blood circulation of children with cerebral palsy. Conclusion : We believe making a practical impact on the growth and development, functional recovery of daily life, and improvement of quality of life of children with cerebral palsy by utilizing Probody Massage Program improves blood pressure (an index of inflammation), pulse, sitting, crawling, and the joints' range of motion as an angle of the shoulder joints' upper limb movement of children with cerebral palsy.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.2
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• pp.154-161
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• 2014

Demands for Korean Traditional Residence Complexes as a more humane resident space have recently been increasing for the purposes of users' health and convenience, built with the purpose of reflecting various trends. This study is aimed at examining the physical characteristics of design in residence complexes by analyzing the physical characteristics of the sound environment as auditory elements of Hanok Complexes and the relationship between spatial and visual test values. The results were shown as follows: In subjective evaluation at Hanok, Natural sounds were recognized higher but artificial sounds were lower. According to the interrelationship analysis between subjective evaluation and physical measurement values, entrance (regular-StdDev), yard (regular-NbEm, friendly-G), waterside (regular-articulation index(rooms), StdDev, $L_{min}$, Rem), etc had been shown highly related.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.2.1-2.6
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• 2020

Background: Facial palsy treatment comprises static and dynamic techniques. Among dynamic techniques, local temporalis transposition represents a reliable solution to achieve facial reanimation. The present study describes a modification of the temporalis tendon transfer using a cryopreserved fascia allograft. Case presentation: Between March 2015 and September 2018, seven patients with facial palsy underwent facial reanimation with temporalis tendon transfer and fascia lata allograft. Patients with long-term palsy were considered, and both physical and social functions were evaluated. The mean follow-up time was 21.5 months. No immediate complications were observed. Patients reported improvement in facial symmetry both in static and dynamic. Improvement was noticed also in articulation, eating, drinking, and saliva control. The Facial Disability Index revealed an improvement both in physical function subscale and in the social/well-being function subscale. Conclusions: This modified orthodromic technique allows to reduce the operative time and the risk of complications connected to the use of autologous tissues. The use of the cryopreserved fascia allografts from cadaveric donors seems to provide promising and long-standing results in the treatment of facial palsy.

• Phonetics and Speech Sciences
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• v.13 no.1
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• pp.37-44
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• 2021

While recent acoustic studies have reported associations of fronted sibilants (fricatives /s s⁎/ and affricates /tɕ tɕ⁎/) with gender in Seoul Korean, there have not been any studies examining the relationship of the variants with adult speakers' ages. The current study analyzes sibilant productions from 39 adult speakers born between 1942 and 2008 (19 females) in terms of spectral peak frequencies (SPFs) in frication, an acoustic index of place of articulation (POA). The results indicate some phonetic contexts where higher sibilant SPFs, i.e., fronter POAs, are associated with younger adults and those fronted variants are realized in a gender-differentiated manner -- tense affricates and word-initial tense fricatives before /i/ in the females' productions, and word-medial tense fricatives before /a/ in the males' productions. The findings confirm that the distributions of the fronted sibilants are accounted for not only by the speakers' gender but also by their ages, indicating that the fronted variants are innovative forms of realizing sibilants in Seoul Korean. In addition, the current results convincingly show that the fronted sibilant variants are not mere reflections of individuals' physiological differences since they are not observed across all of the examined phonetic contexts.

• Phonetics and Speech Sciences
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• v.13 no.2
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• pp.57-66
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• 2021

This study focuses on the issue of automatic severity classification of dysarthric speakers based on speech intelligibility. Speech intelligibility is a complex measure that is affected by the features of multiple speech dimensions. However, most previous studies are restricted to using features from a single speech dimension. To effectively capture the characteristics of the speech disorder, we extracted features of multiple speech dimensions: voice quality, prosody, and pronunciation. Voice quality consists of jitter, shimmer, Harmonic to Noise Ratio (HNR), number of voice breaks, and degree of voice breaks. Prosody includes speech rate (total duration, speech duration, speaking rate, articulation rate), pitch (F0 mean/std/min/max/med/25quartile/75 quartile), and rhythm (%V, deltas, Varcos, rPVIs, nPVIs). Pronunciation contains Percentage of Correct Phonemes (Percentage of Correct Consonants/Vowels/Total phonemes) and degree of vowel distortion (Vowel Space Area, Formant Centralized Ratio, Vowel Articulatory Index, F2-Ratio). Experiments were conducted using various feature combinations. The experimental results indicate that using features from all three speech dimensions gives the best result, with a 80.15 F1-score, compared to using features from just one or two speech dimensions. The result implies voice quality, prosody, and pronunciation features should all be considered in automatic severity classification of dysarthria.

• Phonetics and Speech Sciences
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• v.14 no.4
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• pp.25-33
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• 2022

This study investigates the relationships between rhythm and fluency indices and listeners' ratings of the rhythm and fluency of Korean college students' English paragraph reading. 17 university students read and recorded a passage from "The North Wind and the Sun" twice before and after three months of English pronunciation instruction. Seven in-service and pre-service English teachers in graduate school assessed the rhythm and fluency of the utterances. In addition, the values of 14 indices of rhythm and fluency were extracted from each speech and the relationships between the indices and the listeners' ratings were analyzed. The rhythm indices of the speakers in this study did not differ significantly from those of native English speakers presented in previous studies in %V, VarcoV, and nPVIV, but were higher in ΔV, ΔC, and VarcoC and lower in speech rate. The level of rhythm and fluency demonstrated by Korean college students was comparable, at least in terms of objective values for certain indices. The fluency indices, such as percentage of pauses, articulation rate, and speech rate, significantly contributed more to predicting both rhythm and fluency ratings than the rhythm indices.