저전력 블루투스를 이용한 무선 인버터 모니터링 및 제어 시스템 설계 및 구현

이민제,안효정,임재환,유영규,이정준 한국정보통신설비학회 2017 한국정보통신설비학회 학술대회 Vol.2017 No.08

초고압 송전선로의 코로나 및 전자계영향

이민제,Lee, Min-Je 한국전자통신연구원 1982 전자통신 Vol.4 No.1

전력용 Gapless 피뢰기

이민제 대한전기학회 1980 전기의 세계 Vol.29 No.6

본고의 내용은 다음과 같다. 1. 원리와 특징 2. 전력용 ZnO소자의 제조법과 특성의 개요 3. 제품화의 현황과 금후의 과제

OPC UA 기본 표현을 지원하는 임베디드 프로세서 기반의 Modbus to OPC UA 서버 설계 및 구현

이민제,임창준,유승호,유영규,서장철 한국정보통신설비학회 2020 한국정보통신설비학회 학술대회 Vol.2020 No.09

Study on the Preparation and Characterization of Ophthalmic Polymer with High and Low-Water Content

이민제,성아영 대한화학회 2017 대한화학회지 Vol.61 No.6

This study was planned considering the chain length, hydrophilicity, and hydrophobicity of the additives to be used in the polymerization, while various ophthalmic lenses that use various additives with similar water contents were manufactured before their optical and physical properties were compared and analyzed. With regard to the additives required for manufacturing high-, medium-, and low-water content lens groups, HEA (hydroxyethyl acrylate), PVP (polyvinylpyrrolidone), and NMV(N-methyl-N-vinylacetamide) were used as additives for preparing the high-water content lens group, HEMA(2- hydroxyethyl methacrylate), HPMA(hydroxypropyl methacrylate) and BD(1,4-butanediol) were used for the medium-water content lens group. For the low-water content lens group, BMA(buthyl methacrylate), BDDA(1,4-butanediol diacrylate), and Bis-GMA(bisphenol A glycerolate diacrylate) were used, respectively. The average water content of HEA was 40.14%; that of PVP, 39.63%; and that of NMV, 40.52%. The mean of water content was 35.92% for HEMA, 35.74% for BD, and 34.62% for HPMA. For the low-water content lens group, the mean of water content was 26.69% for BMA, 27.76% for BDDA, and 26.14% for Bis-GMA. With regard to the results of the water content measurement using a moisture analyzer, the average water content of the high-water content lens group was 41.34% for HEA, 42.62% for PVP, and 42.73% for NMV. Finally, for the lowwater content lens group, the average water content was 28.62% for BMA, 28.82% for BDDA, and 28.32% for Bis-GMA. The measurements of the water contents of the lenses using the two methods showed that the water content and refractive index of the lenses were similar in all the lens groups. The measurements of the contact angles, however, showed a different wettability value for each lens with a similar water content. Also, the change tendency of the lens curvature according to the change of time showed that the change amount became larger and the recovery time became longer from the lens samples with a lower water content to those with a higher water content. Based on these results that will be helpful for the study of ophthalmic lenses.

하이드록시기를 포함한 아크릴레이트계 모노머들의 하이드로젤 친수성 렌즈 소재로의 응용 및 특성

이민제,김태훈,성아영,Lee, Min-Jae,Kim, Tae-Hun,Sung, A-Young 대한화학회 2016 대한화학회지 Vol.60 No.3

The hydrophilic ophthalmic lens with addition of 2-hydroxyethyl acrylate (HEA), 2-hydroxyethyl methacrylate (HEMA), hydroxypropyl methacrylate (HPMA) and Ag nanoparticles were manufactured. And also, the cross-linker ethylene glycol dimethacrylate (EGDMA) and the initiator azobisisobutyronitrile (AIBN) were used for polymerization. The polymerization of the hydrogel lens material was conducted through thermal polymerization in 100 ℃ for 1h. The optical and physical characteristics of hydrogel lens were evaluated by measuring water content, refractive index and optical transmittance. The water content of sample containing HEA, HEMA and HPMA was in the average of 82.12%, 37.06% and 21.57%, respectively. And also, refractive index of the sample containing HEA, HEMA and HPMA was in the average of 1.3540, 1.4330 and 1.4649, respectively. In case of the optical properties of the sample, the results showed that the near-UV transmittance was 82.67%, 80.32% and 79.83%, and the visible transmittance was 89.72%, 88.24% and 86.89%, respectively. And also, optical transmittance of the sample containing Ag nanoparticles showed that the near-UV transmittance of 10.59% and visible transmittance of 43.74% were obtained. From the results, the molecular length influenced on the water content and refractive index of the polymerized material. 친수성 안의료용 렌즈 재료에 하이드록시기를 가진 아크릴레이트계 모노머인 HEA(2-hydroxyethyl acrylate), HEMA(2-hydroxyethyl methacrylate), HPMA(hydroxypropyl methacrylate) 및 Ag nanoparticles가 첨가제로 사용되었으며, 교차결합제인 EGDMA(ethylene glycol dimethacrylate)와 개시제인 AIBN(azobisisobutyronitrile)을 사용하여 공중합하였다. 하이드로젤 친수성 렌즈는 100 ℃에서 1시간 동안 열 중합을 통해 제조되었다. 제조된 하이드로젤 친수성 렌즈의 함수율, 굴절률 그리고 광투과율을 측정함으로써 렌즈의 광·물리적 특성을 분석하였다. HEA, HEMA 그리고 HPMA의 평균 함수율은 82.12%, 37.06% 그리고 21.57%로 각각 측정되었으며, 굴절률의 경우 1.3540, 1.4330 그리고 1.4649로 각각 측정되었다. 제조된 하이드로젤 친수성 렌즈의 분광투과율을 측정한 결과, 근자외선 영역에서는 82.67%, 80.32% 그리고 79.83%로, 가시광선 투과율의 경우 89.72%, 88.24% 그리고 86.89%로 각각 측정되었다. 또한 은 나노입자를 포함한 시료의 광투과율은 근자외선 영역에서 10.59% 그리고 가시광선 투과율에서 43.74%로 각각 측정되었다. 이 결과로 볼 때 분자길이는 중합된 고분자 물질의 함수율 및 굴절률에 영향을 주는 것으로 판단된다.

카드뮴 반응용량 곡선에서의 기준용량 평가를 위한 베이지안 분석연구

이민제,최태련,김정선,우해동,Lee, Minjea,Choi, Taeryon,Kim, Jeongseon,Woo, Hae Dong 한국통계학회 2013 응용통계연구 Vol.26 No.3

본 논문에서는 카드뮴의 반응-용량 모형에 대한 베이지안 분석을 실시하고 기준용량에 대한 추정값들을 유도하고 비교한다. 이를 위하여 독성물질에 대한 용량반응곡선에서 많이 활용되는 두 가지 모형을 사용하고, 카드뮴의 독성연구에 관련한 기존의 문헌으로 수집된 자료에 대한 성별, 연령, 인종, study code 등과 같은 소집단 간의 개별적 형질을 반영할 수 있는 베이지안 메타분석 관점에서의 모형분석을 실시한다. 이러한 두 가지 모형에 대한 베이지안 분석을 위하여 WinBUGS를 이용한 마르코프 연쇄 몬테칼로(Markov chain Monte Carlo; MCMC) 방법을 통하여 모수를 추정하고 이에 따른 다양한 기준용량들을 계산하고 비교해보았다. 베이지안 모형 적합뿐만 아니라 편차정보기준을 통해서 주어진 자료를 더 잘 설명하는 모형을 선택하는 베이지안 모형 선택을 고려하였고, 이를 실제 자료에 적용해본다. In this paper, we consider a Bayesian analysis of the dose-effect relationship of cadmium to evaluate a benchmark dose(BMD). For this purpose, two dose-response curves commonly used in the toxicity study are fitted based on Bayesian methods to the data collected from the scientific literature on cadmium toxicity. Specifically, Bayesian meta-analysis and hierarchical modeling build an overall dose-effect relationship that use a piecewise linear model and Hill model, where the inter-study heterogeneity and inter-individual variability of dose and effect such as gender, age and ethnicity are accounted. Estimation of the unknown parameters is made by using a Markov chain Monte Carlo algorithm based user-friendly software WinBUGS. Benchmark dose estimates are evaluated for various cut-offs and compared with different tested subpopulations with with gender, age and ethnicity based on these two Bayesian hierarchical models.

홀더종류에 따른 소프트 콘택트렌즈의 정점굴절력 측정의 정확도 분석

이민제,성아영 한국안광학회 2015 한국안광학회지 Vol.20 No.2

Purpose: The accuracy for measuring the refractive power of hydrogel contact lenses by spectacle lens holder and contact lens holder was evaluated. The accuracy for each sample was also analyzed with water content and diopter categories. Methods: The hydrogel contact lenses used for measurement were classified into three categories in water content (38%, 43%, 58%). Also, three diopter categories of refractive power were used such as −3.000 D, −7.000 D, −10.000 D. And also, the reliability of measurement results were evaluated by measuring refractive power with spectacle lens holder and contact lens holder using an Manual lensmeter. Results: In case of spectacle lens holder method, the average value of refractive power was −3.3273D for −3.0000 D, −7.1306 D for −7.0000 D and −10.2944 D for −10.0000 D, respectively. In case of contact lens holder method, the average value of refractive power was −3.1060 D for −3.0000 D, −7.0028 D for −7.0000 D and −10.2611 D for −10.0000 D, respectively. In measurement of all diopters, the accuracy of contact lens holder method was better than spectacle lens holder method. Conclusions: From these results, it is judged that the refractive power of soft contact lens by manual lensmeter with contact lens holder have a higher accuracy than spectacle lens holder. 목적: 본 연구는 안경렌즈홀더와 콘택트렌즈홀더를 사용하여 다양한 디옵터와 함수율을 가진 소프트 콘택트렌즈의 굴절력을 측정하고 정확도를 평가하여 그 차이를 비교하였다. 방법: 실험에 사용한 소프트 콘택트렌즈의 함수율은 각각 38%, 43% 및 58%이었으며, 굴절력에 따라 −3.000 D, −7.000 D 및 −10.000 D로 분류하여 각각 실험하였다. 또한 망원경식 렌즈미터를 사용하여 안경렌즈홀더 및 콘택트렌즈홀더로 각각의 정점굴절력을 측정하여 정확도를 분석하였다. 결과: 안경렌즈홀더를 사용한 경우 −3.0000 D는 −3.3273 D로 측정되었으며, −7.0000 D는 −7.1306 D, −10.0000 D는 −10.2944D로 각각 측정되었다. 또한 콘택트렌즈홀더를 사용한 경우 −3.0000 D는 −3.1060 D로 측정되었으며, −7.0000 D는 −7.0028 D, −10.0000 D는 −10.2611 D로 각각 측정되었다. 모든 종류의 콘택트렌즈에서 콘택트렌즈홀더를 사용한 방법이 안경렌즈홀더를 사용한 방법보다 더 정확한 측정값을 나타내었다. 결론: 위 결과로볼 때, 망원경식 렌즈미터를 사용한 소프트 콘택트렌즈의 굴절력 측정에 있어 콘택트렌즈홀더를 사용한 방법이 안경렌즈홀더를 사용한 방법보다 더 높은 정확도를 가진 것으로 판단된다.

각종 수치전계계산법의 비교와 응용

이민제 대한전기학회 1981 전기의 세계 Vol.30 No.7

친수성 소프트 콘택트렌즈의 물리적 특성에 미치는 습윤성 재료의 영향

이민제(Min Jae Lee),성아영(A Young Sung),김태훈(Tae Hun Kim) 한국안광학회 2014 한국안광학회지 Vol.19 No.1

Purpose:The physical and optical characteristics of hydrophilic contact lens polymerized with addition of glycerin and PVP(polyvinylpyrrolidone) in the basic hydrogel contact lens material were evaluated. Methods: This study used glycerin and PVP(polyvinylpyrrolidone) with the cross-linker EGDMA (ethylene glycol dimethacrylate), HEMA (2-hydroxyethyl methacrylate) and the initiator AIBN (azobisisobutyronitrile) for copolymerization. Results: Measurements of the physical characteristics of the copolymerized material including PVP(polyvinylpyrrolidone) showed the refractive index of 1.4382~1.4288, tensile strength of 0.3446~2542 kgf and water content and contact angle of sample showed the increase of 13.49% and decrease of 21.44% independently. And also, the physical characteristics of the copolymerized material including glycerin showed the refractive index of 1.4330~1.4328, tensile strength of 0.2974~0.2854 kgf, water content 35.58~36.53% and contact angle of sample showed the decrease of 37.64%. Conclusions: Based on the results of this study, the produced copolymers is suitable for conventional lens with high wettability. Also, glycerin minimized the changes of water content and refractive index at the same time, increased the wettability of the hydrogel lens materials.