• Phonetics and Speech Sciences
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• v.11 no.4
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• pp.63-70
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• 2019

This study investigated individual variability of L2 learners' categorical judgments of L2 stops by exploring English learners' perceptual processing of two acoustic cues (voice onset time [VOT] and f0) and working memory capacity as sources of variation. As prior research has reported that English speakers' greater use of the redundant cue f0 was responsible for gradient processing of native stops, we examined whether the same processing characteristics would be observed in L2 learners' perception of Korean stops (/t/-/t^h/). 22 English learners of L2 Korean with a range of L2 proficiency participated in a visual analogue scaling task and demonstrated variable manners of judging the L2 Korean stops: Some were more gradient than others in performing the task. Correlation analysis revealed that L2 learners' categorical responses were modestly related to individuals' utilizations of a primary cue for the stop contrast (VOT for L1 English stops and f0 for L2 Korean stops), and were also related to better working memory capacity. Together, the current experimental evidence demonstrates adult L2 learners' top-down processing of stop consonants where linguistic and cognitive resources are devoted to a process of determining abstract phonemic identity.

• Bulletin of the Society of Naval Architects of Korea
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• v.14 no.1
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• pp.1-10
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• 1977

The major objects of this report are to supplement data of natural frequencies of thin elastic rectangular plates to the available data, and to give an experimental verification for natural frequencies obtained by Rayleigh-Ritz method, the generation set of which are eigenfunctions of Euler beams. For the first object the following five models, for which data only for the fundamental mode or data only for square plates are available, are adopted; (1) two opposed edges are clamped and the other two opposed edges simply supported (C-C, S-S), (2) one edge is simply supported and the other three edges clamped (C-C, C-S), (3) one edge is free and the other three edges clamped (C-C, C-F), (4) two adjacent edges are clamped and the other two adjacent edges free (C-F, C-F). For the (C-C, S-S) model the frequency equation obtained with the mode shapes assumed as of a single trigonometric series is solved. And for the other four models Rayleigh-Ritz method taking eigenfunctions of Euler beams as the generating set is applied. The numerical examples are obtained up to the fourth, the fifth or the sixth order depending on the range of the aspect ratio (0.1-10.0). The number of terms in the generating set for Rayleigh-Ritz method is fifteen for all models. For the experiment three models made of 3.2mm thickness mild steel plate for general structure use were prepared in following size; $300mm{\times}600mm,\;600mm{\times}600mm\;and\;900mm{\times}600mm$. Their boundary conditions are made to fit (C-C, C-F) condition. From the experiment mechanical impedance curves based on the frequency response method were obtained together with phase relation diagrams. The experimental data are resulted in good conformity to calculated values.

• Speech Sciences
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• v.14 no.3
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• pp.7-19
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• 2007

The present study investigated some phonetic attributes which distinguish two Korean stop types $^-aspirated$ and $lax^-$ in a prosodic position which has previously received little attention, namely medial in an accentual phrase. The intonational pattern across syllables which are initial in an accentual phrase (Jun, 1993) is said to depend on the type of stop (aspirated or lax), while that of syllables which are medial in an accentual phrase are not. In Experiment 1, nine native Korean speakers read sentences with a controlled prosodic pattern in which aspirated or lax stops occurred in accentual phrase-medial position. Acoustic analysis revealed significant differences between aspirated and lax stops in closure duration, voice-onset time, and fundamental frequency (F0) values for post-stop vowels. The results indicate that a wider range of acoustic cues distinguish aspirated and lax Korean stops than previously demonstrated. Phonetic and phonological models of consonant-tone interactions for Korean will need to be revised to account for these results.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.17 no.1
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• pp.43-48
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• 2006

Background and Objectives: Countertenors who can produce higher vocal pitch like female classical singer's voice and use both modal and falsetto register. This study was conducted to study phonatory characteristics between modal and falsetto register of the countertenor. Materials and Methods: A male countertenor who had 8 years of experience was examined using a videostroboscopy and his voice was analyzed using aerodynamic measures; fundamental frequency(F0), Mean air flow rate(MFR), intensity(SLP), subglottal air pressure(Psub) with phonatory function analyzer(Nagashima) and acoustic measures; jitter, shimmer, HNR, closed quotient(CQ) using a Electro-glottography(EGG) of Lx. Speech Studio(Laryngoscope, Ltd, UK) and voice range profile of CSL(Kay elemetrics). Results: In the stroboscopy finding, the longitudinal length of vocal folds was increased at the falsetto register and the upper margin of vocal folds vibrated with incomplete closure of true vocal folds. In aerodynamic analysis, intensity was same at the modal and falsetto register. However, MFR, Psub, MPT were higher at the falsetto register. In the electroglottographic analysis, closed quotient(CQ) at the modal register was high and also much higher at the high-pitch falsetto than at the loud falsetto. In the VRP, intensity was similar though F0 was different between modal and falsetto register. Conclusion: It implied that countertenor could produce powerful voice quality by increasing of respiratory pressure and respiratory volume though glottal closure was incomplete. In addition, no change of EGG waveform, similar voice range with alto was observed.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.16 no.1
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• pp.68-75
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• 2005

The treatment of sulcus vocalis and vocal bowing has been commonly used Thyroplasty Type surgery or injection within vocal folds such as Teflon, silicone, collagen. However, and treatment has not been acquired satisfactory treatment effect. This study was conducted to demonstrate voice therapy effect using singer's vocal technique and respiratory training. 4 patients (1 male, 3 females) with sulcus vocalis or bowing, with or without scar were selected for this study and we compared with acoustic, aerodynamic measures and stroboscopy observation before and after voice therapy. The results showed that 1) case 1 (48yr, male) with sulcus vocalis decreased F0 (Fundamental Frequency), increase CQ(Close Quotient) and high degree of satisfaction but not improved voice quality after voice therapy. 2) case 2(19yrs, femal) with mild sulcus vocalis improved as normal voice quality after voice therapy. 3) case 3(38yrs, female) with functional bowing showed abnormalvocal contact before therapy whereas CQ was increased after voice therapy. 4) case 4(27yrs, female) with vocal atrophy and vocal bowing changed normal range of Fo and increased CQ after voice therapy. Even though contact area of both vocal folds was increased and lowered F0 after voice therapy, current outcomes revealed that normal voice quality was not regained. These results might signify that it was difficult that vocal folds couldn't be recovery of symmetry and viscoelastic property of mucosal wave through voice therapy. However, it was difficult for this study to maintain voice therapy so that evaluate effect of voice therapy for long-term. Further study will be needed to long-term follow-up for voice therapy with these patients.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.27 no.2
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• pp.108-113
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• 2016

Background and Objectives : After thyroidectomy, many patients experience problems report such things as reduced voice range and vocal fatigue, swallowing problems without superior and recurrent laryngeal nerve injury. The purpose of this study was to evaluate voice and swallowing problems before and after thyroid surgery without laryngeal nerve injury. Materials and Methods : Ninety-three patients who underwent thyroidectomy without laryngeal nerve injury and completed the follow-up evaluations were studied between June 2013 and December 2015. Each evaluation was performed preoperatively, as well as 1 week, 1 month postoperatively. Analysis was performed including voice handicap index (VHI), dysphagia handicap index (DHI), and acoustic voice analysis. Results : Patients show significant variation of parameters in the fundamental frequency (F), maximal phonation time (MPT), shimmer, jitter and soft phonation index (SPI) early after operation, and most of them showed recovery of parameters after 1month of operation. Perceptive complaint of voice and swallowing also showed significant decreased after operation (p<0.005). After 1month of operation, MPT, highest frequency and frequency ranges still showed significant decreased parameters. Comparing acoustic and perceptive parameters of total thyroidectomy and lobectomy, there was no significant changes between them except highest frequency (p=0.042). Conclusion : The results from both subjective and objective evaluations show voice and swallowing disturbance after thyroidectomy even in the absence of laryngeal nerve and provide patients information about the recovery process after surgery. Highest frequency parameter showed most significant changes after operation.