• 한국세라믹학회지
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• 제50권6호
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• pp.416-422
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• 2013

Cullet-loess tile bodies are successfully fabricated using cullet, loess, hollow microspheres, and sintering additives (borosilicate glass frit, boric acid, or fumed silica) as starting materials. The effects of the additive composition and sintering temperature on the sintered density and flexural strength of the cullet-loess tile bodies are investigated. The sintered density of the cullet-loess tile bodies increases with an increase in the sintering temperature as a result of the enhanced densification of pore walls through the viscous flow of a liquid phase formed from the glass frit and sintering additives. The flexural strength of the cullet-loess tile bodies increases with increases in the sintering temperature and the cullet content in the starting composition. A maximal flexural strength of 40 MPa is obtained in cullet-loess tile bodies sintered with glass frit at $800^{\circ}C$ in air.

• 한국임상보건과학회지
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• 제4권4호
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• pp.671-679
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• 2016

Purpose. This research study is to understand the effects of field (clinical) Practice on employment choice and decision. Method. The research study conducts a questionnaire survey of trainees who received field (clinical) Training during the period of 2016 summer vacation to analyze the data, utilizing Likert 5 rating scales and conduct a statistical analysis with the tool of SPSS 18.0. Results.. As for the satisfaction of the participation of Practice, girl students account for the high rate (75.1%) compared with boy students (61.7%). Regarding the satisfaction of each Practice spot, ophthalmic clinic reaches the high rate (77.8%) compared with optical shop (65.7%). Practice about practice courses (53.2%) of regular subjects have somewhat close correlations compared with theory courses (46.8%). 75.2% of respondents in the group that shows the high satisfaction of the participation of Practice replied that they would decide employment as an academic major after Practice. And the figure is proved to assume a high ratio. Conclusion. The analytic research outcome indicates that those trainees who received Practice in an ophthalmic clinic have higher satisfaction than those who received Practice in an optical shop. There is the high accomplishment of employment in relation to academic major area instead of other area, after Practice.

• 한국임상보건과학회지
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• 제7권2호
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• pp.1345-1354
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• 2019

Purpose: This study aimed to determine the mediating effects of aggressive stress response on the association between clinical practice stress and clinical practice satisfaction in ophthalmic optics majors and provide basic data that could help form opticians' professionalism and make clinical practice more effective. Methods: This study was conducted in 236 sophomores and juniors in Daegu and North Gyeongsang Province who had finished clinical practice. Hierarchical regression analysis and mediating effect testing were performed to determine the associations among clinical practice stress, clinical practice satisfaction, and aggressive stress response and determine the mediating effects of aggressive stress response on the association between clinical practice stress and clinical practice satisfaction. Results: Clinical practice stress was significantly negatively correlated with clinical practice satisfaction and aggressive stress response (p<0.01), and aggressive stress response was significantly positively correlated with clinical practice satisfaction (p<0.01). The association between clinical practice stress and clinical practice satisfaction was more likely to be explained by the addition of clinical practice stress than by being aggressive stress response controlled, which statistically significantly met the criteria for mediating effects (p<0.001). Conclusions: It is necessary to pay more attention to program development and teaching methods within the department of ophthalmic optics so that ophthalmic optics majors can utilize aggressive stress response to overcome clinical practice stress effectively and improve clinical practice satisfaction.

• 폴리머
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• 제36권2호
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• pp.190-195
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• 2012

소프트 콘텍트 렌즈의 재질 별 계면학적 특성 및 유변학적 변화를 조사하여 렌즈 재료의 성분 설계에 기본 정보를 제시하고자 하였다. 눈물 단백질인 albumin과 IgG의 흡착량을 측정한 결과 하이드로젤의 표면 에너지가 증가함에 따라 점차 단백질 흡착량이 감소하는 것을 볼 수 있었다. Polydimethylsiloxane-polyvinylpyrrolidone(PDMS-PVP) 하이드로젤은 albumin과 IgG 흡착량이 가장 높았으며 poly(2-hydroxyethyl methacrylate)-polyvinylpyroolidone(HEMA-PVP)의 경우 albumin의 흡착량은 매우 미미한 것으로 나타났다. 일정한 수직항력 하에서의 하이드로젤의 토크는 실리콘 재질인 PDMS-PVP의 경우 HEMA계열보다 약 5배 이상 크게 측정된 것을 볼 수 있었다. 흥미로운 것은 단백질 흡착량이 적은 HEMA계열 하이드로젤의 경우 실리콘 계열 하이드로젤보다 인공 눈물 내 거동 시 마찰계수가 오히려 더 큰 것을 알 수 있었다. 인공눈물 내의 하이드로젤의 거동은 단백질 흡착으로 인한 윤활 효과 외에도 하이드로 젤 고유의 구조와 회전하는 계면의 성질에 큰 영향을 받는 것을 알 수 있었다.

• 한국정보통신학회논문지
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• 제19권7호
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• pp.1646-1652
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• 2015

본 논문에서는 집적영상에서 정치실영상을 재생하기 위한 깊이변환법을 제안한다. 종래의 집적영상은 재생상이 반전된 깊이로 재생되는 도치영상 문제가 있다. 재생상의 깊이는 개별 요소영상의 좌표에 의해 결정된다. 요소영상 획득과 재생시스템의 기하학적 관계를 분석하여 재생상의 깊이 변환 에 필요한 수식 유도가 가능하며 이를 이용하여 도치영상을 정치영상으로 변환할 수 있다. 제안하는 방법의 유용성을 보이고 또한 이론적 분석을 검증하기 위하여 실험을 수행하였고 그 결과를 제시한다.

• 한국임상보건과학회지
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• 제7권1호
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• pp.1205-1214
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• 2019

Purpose: To investigate the effect of color soft contact lenses on the corneal thickness in young Korean population. Methods: The subjects consisted of 112 eyes (7 males, 49 females) with the mean age of $20.987{\pm}1.093years$ (range 20-25 years) in young Korean population during 2018. Test was compared the corneal thickness before and after wearing color soft contact lenses. The thinnest cornea thickness(TCT), central cornea thickness(CCT), pupil centre thickness(PCT), superior corneal thickness(SCT),inferior corneal thickness(ICT), medial corneal thickness(MCT), lateral corneal thickness(LCT) of the cornea was measured using the Pentacam pachymetry. The statistically analysis was perform the Shaparo-Wilk test. Results: The right eye was a statistically significant among the CCT,LCT, MCT and TCT values(p<0.001) in the compared the corneal thickness before and after wearing soft colour contact lenses. Also the left eye was a statistically significant among the LCT and MCT values(p<0.001) in the compared the corneal thickness before and after wearing soft colour contact lenses. However, there was no statistical difference (p>0.5) in the mean PCT between before and after wearing color soft contact lenses. Conclusion: These results suggested that the color soft contact lens wear can the effect the regional thickness of cornea. Therefore, the analysis of corneal topography with Pentacam can provide correct and useful diagnostic information of the morphology of the RGP contact lens fitting and diagnosis of corneal refraction surgery.

• 한국임상보건과학회지
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• 제9권1호
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• pp.1462-1468
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• 2021

Purpose; The purpose of this study is to objectively identify and quantify the wearer's feelings of wearing glasses. Methods: The temperature of the skin on the nose ridges and ear, and the area where the glasses were seated, was measured using a thermal imaging camera. Results: Before wearing the glasses, the temperature of the skin surface on the nasal ridge was 34.908 ± 0.875 ℃ and the temperature of the ear region was determined as 31.981 ± 0.549 ℃. The changed temperature measured at 5 minutes later after taking off the glasses showed that the nasal ridge was determined as 35.467 ± 0.342 ℃ and the ear area was determined as 32.994 ± 0.412 ℃ (p<0.05). Conclusions: In this experiment, it was revealed that the glasses cause discomfort and heat in the fitting area. It was the first attempt to study objectively and scientifically. Analysis of frame fitting points by using thermal camera is expected to be helpful when consulting a sensitive person about changes in the fit of glasses.

• 한국임상보건과학회지
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• 제10권1호
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• pp.1553-1558
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• 2022

Purpose: The aim of this study was to determine the association between stigmatism and amblyopia. Methods: It was a hospital based, cross-sectional retrospective study conducted in Nepal Eye Hospital. Medical record of amblyopic children aged 13 years or younger from were reviewed. Children with amblyopic eyes due to simple astigmatism were included. Relation between depth of amblyopia with magnitude and types of astigmatism, orientation of axis was determined. Out of 139 amblyopic eyes of 82 children, 93 were simple myopic astigmatism and remaining 42 were simple hyperopic astigmatism. Results: Mean age of patients was 7.38±2.61 years. Visual acuity improved by at least one line in Snellen chart in 4/5th of eyes after astigmatic correction. Moderate amblyopia was found to be present in 45% eyes while severe amblyopia in 16% of eyes. With the rule astigmatism was found to be present in 88% eyes. Mean astigmatism was 2.47±0.98D and majority of eyes (67.7%) had high astigmatism. Depth of amblyopia was not associated with magnitude of astigmatism (p > 0.05) but number of lines improved with astigmatic correction was correlated with the magnitude of astigmatism (p < 0.001). Risk of amblyopia is more in high myopic astigmatism. Conclusion: Presenting age of amblyopic children was late in Nepal. Depth of amblyopia was not associated with magnitude of astigmatism.

• 한국임상보건과학회지
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• 제11권1호
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• pp.1632-1638
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• 2023

Purpose: The aim of this study was to determine the distribution of the cornea thickness and intra ocular pressure Korean adult of 20 to 24 year old using the Pentacam and tonometer. Methods: The subjects of this study were 43 Korean adults with healthy eyes. Corneal thickness was measured with Pentacam device. The intra ocular pressure was measured with tonometer. Data was analyzed by means of the Pearson's correlation cofficient. P-values<0.001 were considered statistically significant. Results: Mean age of subjects was 20.41±0.86 years. The mean +/- intra ocular pressure of the right eye and left eye were 16.236±2.523mmHg and 16.971±1.992mmHg, respectively. The mean central corneal thickness of the right eye and left eye was 545.324±38.682㎛ and 547.442±33.778㎛, respectively. No significant difference in central corneal thickness was found between the right and left eyes. But, there was a statistically significant difference between central cornea thickness and peripheral cornea thickness around 4 mm of central cornea(p<0.001, Pearson's correlation). However there was no statistically significant difference between central cornea thickness and intra ocular pressure. Conclusion: The results of this study could be used as a clinical reference data for diagnosis and treatment of cornea in Korean adult.

• 한국안광학회지
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• 제18권1호
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• pp.85-91
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• 2013

목적: 본 연구는 근시안에서 현성굴절검사(manifest refraction: MR)와 조절마비굴절검사(cycloplegic refraction: CR)값을 비교하여 연령과 근시도에 따라 차이가 있는지 알아보고자 하였다. 방법: 근시성 굴절이상을 가진 229명 ($25.3{\pm}11.9$세)을 대상으로 조절마비제(cyclogyl 1%) 점안 전과 후에 자각적 굴절검사를 시행하였다. 결과: 조절마비제 점안 전 후 평균굴절력을 비교 조사하였더니, 근시 0.19 D, 난시 0.02 D 감소하였고 난시방향은 1.85도 차이를 보였다. 근시도의 변화는 30~40대에서 가장 높게 나타났으며, 229명(458안) 중 근시도수에서 0.50 diopter(D) 이상의 차이를 보이는 경우는 73안(16%)으로 근시도가 높은 군일수록 오차율이 높게 나타났다. 결론: 현성굴절검사와 조절마비굴절검사 값을 비교해 본 결과 연령에 따른 근시도의 변화는 유의하지 않았으나, 근시도가 높은 군일수록 오차율이 유의하게 높은 것으로 나타났다.