• Phonetics and Speech Sciences
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• v.15 no.3
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• pp.27-35
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• 2023

This study aimed to investigate the effect of Chinese on the production of Korean rhythm. Korean and Chinese are typologically classified into different rhythmic categories; because of this, the phonological properties of Korean and Chinese are similar and different at the same time. As a result, Chinese can exert both positive and negative influences on the realization of Korean rhythm. To investigate the influence of the rhythm of the native language of L2 learners on their target language, we conducted an acoustic analysis using acoustic metrics like of the speech of 5 Korean native speakers and 10 advanced Chinese Korean learners. The analyzed material is a short paragraph of five sentences containing a variety of syllable structures. The results showed that KS and CS rhythms are similar in %V, VarcoV, and nPVI_S. However, CS, unlike KS, showed characteristics closer to those of a stress-timed language in the values of %V and VarcoV. There was also a significant difference in nPVI_V values. These results demonstrate a negative influence of the native language in the realization of Korean rhythm. This can be attributed to the fact that all vowels in Chinese sentence are not pronounced with the same emphasis due to neutral tone. In this sense, this study allowed us to observe influences of L1 on L2 production of rhythm.

• Phonetics and Speech Sciences
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• v.8 no.2
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• pp.1-9
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• 2016

This paper investigated the rhythmic features of speakers of English as a lingua franca in Asian contexts. A speech corpus of 150 conversations between speakers of English in Asia with different L1 backgrounds was collected and %V, ${\Delta}V$, VarcoV, and nPVI-V of each speaker were analyzed. It was found that L1 difference of the speakers and the speakers' daily use of English influenced %V, while the speakers' daily use of English influenced ${\Delta}V$. The gender difference of the speakers also affected the rhythm of the utterances in VarcoV. A weak correlation between the two speakers' rhythm in each conversation was also found in %V and ${\Delta}V$. No significant effects were found in nPVI-V. The results revealed that the speakers tended to accommodate the rhythm of their utterance to that of the interlocutors'. Further study on the speaking rate of the speakers is required to overcome some inconsistencies found in the results of the rhythmic metrics used in this study.

• Phonetics and Speech Sciences
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• v.11 no.4
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• pp.71-79
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• 2019

This study aims to investigate the rhythmic patterns in the English speech produced by Chinese learners of English who learn English as a foreign language (EFL learners). Utilizing interval-based rhythm metrics, namely, VarcoC, VarcoV, nPVI-C, nPVI-V, and %V, the study compared the rhythmic differences in English speech between ten native speakers from the United States and forty Chinese EFL learners from mainland China. A sentence elicitation task consisting of thirty picture prompts and corresponding thirty stimuli sentences with at least five vocalic and four consonantal intervals was conducted. Statistical results reveal that both Chinese advanced learners and beginners had significantly lower degree of stress-timed in their English speech, indicating that the acquisition of the L2 speech rhythm was influenced by the learners' L1 rhythmic pattern. In addition, the results also show that the Chinese advanced learners had significantly higher degree of stress-timed in their English speech than beginners and showed no significant difference with native speakers in VarcoC and nPVI-C. These results indicate that the direction of L2 speech rhythm development was from more syllable-timed to more stress-timed.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3118-3122
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• 2010

The water soluble redox polymer, poly(N-vinylimidazole) complexed with Os(4,4'-dichloro-2,2'-bipyridine)$_2Cl]^+$ (PVI-[Os(dCl-bpy)$_2Cl]^+$), was electrodeposited on the surface of a glassy carbon electrode by applying cycles of alternating square wave potentials between 0.2 V (2 s) and 0.7 V (2 s) to the electrode in a solution containing the redox polymer. The coordinating anionic ligand, $Cl^-$ of the osmium complex, became labile in the reduced state of the complex and was substituted by the imidazole of the PVI chain. The ligand substitution reactions resulted in crosslinking between the PVI chains, which made the redox polymer water insoluble and caused it to be deposited on the electrode surface. The deposited film was still electrically conducting and the continuous electrodeposition of the redox polymer was possible. When cycles of square wave potentials were applied to the electrode in a solution of bilirubin oxidase and the redox polymer, the enzyme was co-electrodeposited with the redox polymer, because the enzymes could be bound to the metal complexes through the ligand exchange reactions. The electrode with the film of the PVI-[Os(dCl-bpy)$_2Cl]^+$ redox polymer and the co-electrodeposited bilirubin oxidase was employed for the reduction of $O_2$ and a large increase of the currents was observed due to the electrocatalytic $O_2$ reduction with a half wave potential at 0.42 V vs. Ag/AgCl.

• Journal of Korean Neurosurgical Society
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• v.29 no.1
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• pp.5-14
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• 2000

Objective : Somatosensory evoked potential(SSEP) has been known to be a good method for evaluating brain stem function, but it is not sufficient to check the fine changes of cortical functions. A fine change of cortical function can be expressed with somatosensory evoked cortical field potential(SSEFP) rather than general SSEP. To confirm the usefulness of SSEFP for evaluating the cortical function, the authors simultaneously measured SSEFP and the intracranial pressure-volume index(PVI) in kaolin-induced hydrocephalic rats. Method : Hydrocephalus was induced with injection of 0.1ml kaolin-suspended solution into the cisterna magna in 60 Sprague-Dawley rats. The authors measured PVI and SSEFP 1 week after injection of kaolin-suspended solution. To evaluate the severity of induced hydrocephalus, we measured the transverse diameter of the lateral ventricle on the coronal slice of the rat brain 0.40mm posterior to the bregma. Result : The typical wave form of SSEFP in control rats showed a negative-positive complex wave at early latency. In SSEFP of normal rats, N0 is 10.0 msec, N1 15.3 msec, P1 31.2 msec and N1-P1 amplitude $15.4{\mu}V$. As hydrocephalus progressed, the peak latency of N1 and P1 were delayed. In mild hydrocephalus, negative peak waves were split. The N1-P1 amplitude was decreased only in severe hydrocephalus. The changes of the characteristics of SSEFP according to the severity of hydrocephalus were well correlated with the changes of PVI. Shunting normalized the characteristics of SSEFP in relation to ventricular sizes and PVI in hydrocephalic rats. Conclusion : SSEFP may be useful for evaluating the impairment of cortical function in hydrocephalus.

• Phonetics and Speech Sciences
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• v.1 no.3
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• pp.49-55
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• 2009

This study investigates whether rhythm metrics can be used to capture the rhythmic differences between spontaneous and read English speech. Transcription of spontaneous speech tokens extracted from a corpus is read by three English native speakers to generate the corresponding read speech tokens. Two data sets are compared in terms of seven rhythm measures that are suggested by previous studies. Results show that there is a significant difference in the values of vowel-based metrics (VarcoV and nPVI-V) between spontaneous and read speech. This manifests a greater variability in vocalic intervals in spontaneous speech than in read speech. The current study is especially meaningful as it demonstrates a way in which speech styles can be differentiated and parameterized in numerical terms.

• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.1902-1906
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• 2011

Sulfonated poly(fluorinated arylene ether)s (SDF-F)/poly[(N-vinylimidazole)-co-(3-methacryloxypropyl-trimethoxysilane)] (poly(VI-co-MPS))/poly(tetrafluoroethylene) (PTFE) is prepared for a high temperature proton exchange membrane fuel cell (PEMFC). The reaction of the membrane with phosphoric acid forms silicate phosphor, as a chemically bound proton carrier, in the membrane. Thus-formed silicate phosphor, nitrogen in the imidazole ring, and physically bound phosphoric acid act as proton carriers in the membrane. The physico-chemical and electrochemical properties of the membrane are investigated by various analytical tools. The phosphoric acid uptake and proton conductivity of the SDF-F/poly(VI-co-MPS)/PTFE membrane are higher than those of SDF-F/PVI/PTFE. The power densities of cells with SDF-F/poly(VI-co-MPS)/PTFE membranes at 0.6 V are 286, 302, and 320 mW $cm^{-2}$ at 150, 170, and 190 $^{\circ}C$, respectively. Overall, the SDFF/poly(VI-co-MPS)/PTFE membrane is one of the candidates for anhydrous HT-PEMFCs with enhanced mechanical strength and improved cell performance.