• 한국어병학회지
• /
• 제33권1호
• /
• pp.55-62
• /
• 2020

본 연구에서는 점액포자충에 의한 넙치의 여윔증 치료 후보물질을 탐색하기 위하여, Coxi-stop, Coxiclin 및 BLEAN80 등의 제품을 사용하여 in vitro 및 in vivo 실험을 실시하였다. 톨트라주릴이 주성분인 Coxi-stop의 경우, BF-2 cell을 사용한 in vitro 실험에서 점액포자충의 활성을 감소시키는 결과를 보였고, cell lysis와 같은 세포 독성 현상이 나타나지 않았다. In vivo 실험에서 Coxi-stop을 사용하여 약욕한 실험군은 대조군에 비하여 누적폐사율이 낮게 나타났으며, 이것은 톨트라주릴이 어류 기생충성 질병에 치료 효과가 있다는 기존의 보고와 유사한 결과이다. 본 연구에서는 톨트라주릴이 넙치의 여윔증 치료제로서 가능성이 있는 후보 물질이라는 것을 제시한다.

• 한국광학회지
• /
• 제32권1호
• /
• pp.9-14
• /
• 2021

본 논문에서는 인공위성용 비축 삼반사 망원경의 조리개 위치에 따른 광학계 연구를 진행하였다. 인공위성 광학 탑재체로 주로 사용되는 비축 삼반사 망원경은 높은 해상도와 넓은 화각을 가져야 한다. 또한, 광학계가 구조적으로 비축상에 위치하여 조립이 어려우므로 넓은 공차범위를 가져야 한다. 그러나 조리개의 위치 선정에 따라 광학계의 성능 차이 이외에도 민감도의 차이가 있어, 사용 목적에 따른 적합한 조리개의 위치 선정이 중요하다. 따라서 본 논문에서는 조리개 위치가 각각 다른 비축 삼반사 망원경을 설계하고 성능 및 민감도 분석을 진행하여 적합한 조리개의 위치를 제시하였다.

• 음성과학
• /
• 제5권2호
• /
• pp.17-26
• /
• 1999

It has been claimed that Korean mid-vocalic voiceless unaspirated lax stops are phonetically realized with voicing throughout the oral closure phase. Acoustic measurements were undertaken to examine the claim with four Korean native speakers using /$V_1CV_2$/ words where the vowel ($V_1\;=\;V_2$) was /i, a, u/ and the C was voiceless unaspirated lax stops /p, t, k/. Findings: (1) During mid-vocalic stops /k/ and /p/ the vowel /u/ was accompanied generally by a significant increase in voice cessation time as percentage of the oral closure interval (PCT) than the vowel /a/, regardless of subjects, whereas in mid-vocalic alveolar stop /t/ the effects of vowels on PCT were subject-dependent, (2) The effects of vowels on PCT were significantly greater in mid-vocalic /k/ than /p/, regardless of subjects, (3) The mean PCT, averaged across six tokens, ranged from 17% to100%, giving overall mean 61% in which the standard deviation was ${\pm}30$, and (4) Overall % of the total of mid-vocalic unaspirated lax stops were produced with a substantial period of devocing and voicing lag. Considering these results, it is difficult to agree with the existing claims that Korean voiceless unaspirated lax stops are phonetically realized with voicing throughout the oral closure phase. Other phonetic variables, including the durations of pre/post-stop vowels, voice onset time, voice cessation time, and the duration of oral closure, were measured.

• 대한음성학회:학술대회논문집
• /
• 대한음성학회 2000년도 7월 학술대회지
• /
• pp.165-165
• /
• 2000

In the phoneme level, English stop sounds are classified with the feature of 'voicing': voiceless and voiced (p/b, t/d, k/g). But when realized, a voiceless stop is not alwats the same sound. For example, the two 'p' sounds in 'people' are different. The former is pronounced with much aspiration, while the latter without it. This allophonic differnece between [$P^h$] and [p] out of an English phoneme /p/ can be well explained to Koreans because in Korean these two sounds exist as two different phonemes {/ㅍ/ and /ㅃ/ respectively). But difficulties lie in teaching the English voiced stop sounds (/b, d, g/) to Koreans because in Korean voiced stops do not exist as phonemes but as allophones of lenis sounds (/ㅂ, ㄷ, ㄱ/). For example, the narrow transcription of '바보' (a fool) is [baboo]. In the word initial position, Korean lenis stops are pronounced voiceless and even with a slight aspiration while in the inrervocalic environments they become voiced, That is in Korean voiced stops do not occur independently and neither they have their own letters. To explain all these more effectively to Koreans, it is very helpful to use Korean Phenetic Alphabet (KPA) which is devised by Dr. LEE Hyunbok (a professor of phonetics at Seoul National Univ. and chairman of Phonetic Society of Koera.)(omitted)

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2010년도 춘계학술대회 논문집
• /
• pp.1111-1112
• /
• 2010

• 음성과학
• /
• 제15권2호
• /
• pp.33-51
• /
• 2008

Difference of learner speech and loanword phonology is investigated in terms of Korean learners' speech and their loanword adaptation of English words with a post-vocalic word-final stop. When we compared the speech of 12 Korean learners in mid-intermediate level with that of eight English speakers, the learner speech did not reflect loanword phonology of the vowel insertion after a voiced word-final stop (e.g., rib$[\dotplus]$, bad$[\dotplus]$, gag$[\dotplus]$ vs. tip[=], cat[=], book[=]), but, instead, the target phonology of vowel lengthening before a voiced word-final stop (e.g., rib[r.I:b], CAD$[k{\ae}:d]$, bag$[b{\ae}:g]$ vs. rip[rI.p], cat$[k{\ae}t]$, back$[b{\ae}k])$. A longitudinal study of learner speech before and after instruction showed some development toward the acquisition of target phonology. The results indicate that learner speech departs from loanword phonology, and approaches to target speech in a faster rate than direct ratio. Thus, native phonology predicts loanword phonology, but lends little support to learner speech. Our results also indicate that loanword phonology is constant, while learner speech changes toward the acquisition of target phonology.

• 말소리와 음성과학
• /
• 제15권3호
• /
• pp.45-52
• /
• 2023

Previous studies have established a role for cognitive differences in explaining variability in speech processing across individuals. In the case of perceptual cue weighting in the context of a sound change, studies have produced conflicting results regarding the relationship between executive function and the use of redundant cues. The current study aimed to explore this relationship in acoustic cue weighting during speech production. Forty-one Korean-speaking children read a list of stop-initial words and completed two tests that assess executive function, i.e., Dimensional Change Card Sorting (DCCS) and digit n-back. Voice onset time (VOT) and fundamental frequency (F0) were measured in each word, and analyses were carried out to determine the extent to which children's executive function predicted their use of both informative and less informative cues to the three pairs comprising the Korean three-way stop laryngeal contrast. No evidence was found for a relationship between cognitive ability and acoustic cue weighting in production, which is at odds with previous, albeit conflicting, results for speech perception. While this result may be due to the lack of task demands in the production task used here, it nevertheless expands the empirical ground upon which future work in this area may proceed.

• 대한교통학회지
• /
• 제24권1호
• /
• pp.97-108
• /
• 2006

현재 우리나라에서는 버스 노선의 정류장 수 및 간격 산정을 위해 전문가의 주관적인 판단에 의존하는 경우가 많다. 좀 더 객관적인 절차를 통해 신뢰성 있는 결과를 얻기 위해 최적 정류장 수 및 간격을 구하는 기존 모형들을 살펴보았지만 하차수요와 임의적인 수요분포를 고려하지 못한다는 한계점을 안고 있었다. 본 연구는 기존 모형들의 이러한 한계를 인식하고 수요를 승차와 하차로 구분하고 그 분포에 라라 일정한 구간별로 서로 다른 최적 정류장 수와 간격을 탄력적으로 산출해 낼 수 있는 모형을 정립하였다. 정립된 모형을 다양한 수요분포를 가지는 간단한 예제노선에 적용해본 결과 승차 혹은 하차수요에 비례하여 구간별 정류장 수가 탄력적으로 산출됨을 알 수 있었다.

• 레드리본
• /
• 통권83호
• /
• pp.16-17
• /
• 2009

이번호에서는 2004년부터 2008년까지 스위스 연방보건국이 펼쳤던 캠페인을 살펴보기로 한다. 홈페이지에 들어가면 HIV/AIDS에 관한 교육적인 내용, 안전하고 올바른 섹스 룰, 콘돔 사용방법 등을 자세하고 소개하고 있다. 하지만 광고캠페인에서는 많은 욕심을 내지 않고, 안전한 성생활을 위해서는 반드시 콘돔을 사용해야한다는 점을 일관되게 주장하고 있다.

• 말소리와 음성과학
• /
• 제14권3호
• /
• pp.1-9
• /
• 2022

The current study examined English-speaking adult learners' production and perception of L2 Korean stops (/t/ or /t'/ or /t^h/) to investigate whether the two modalities are linked in utilizing voice onset time (VOT) and fundamental frequency (F0) for the L2 sound distinction and how the learners' L2 proficiency mediates the relationship. Twenty-two English-speaking learners of Korean living in Seoul participated in the word-reading task of producing stop-initial words and the identification task of labelling CV stimuli synthesized to vary VOT and F0. Using logistic mixed-effects regression models, we quantified group- and individual-level weights of the VOT and F0 cues in differentiating the tense-lax, lax-aspirated, and tense-aspirated stops in Korean. The results showed that the learners as a group relied on VOT more than F0 both in production and perception (except the tense-lax pair), reflecting the dominant role of VOT in their L1 stop distinction. Individual-level analyses further revealed that the learners' L2 proficiency was related to their use of F0 in L2 production and their use of VOT in L2 perception. With this effect of L2 proficiency controlled in the partial correlation tests, we found a significant correlation between production and perception in using VOT and F0 for the lax-aspirated stop contrast. However, the same correlation was absent for the other stop pairs. We discuss a contrast-specific role of acoustic cues to address the non-uniform patterns of the production-perception link in the L2 sound learning context.