계면안정화를 통한 Si-SiO₂-흑연 복합재 음극의 전기화학적 특성 개선

민정혜,배영산,김성수,송승완,Min, Jeong-Hye,Bae, Young-San,Kim, Sung-Su,Song, Seung-Wan 한국전기화학회 2012 한국전기화학회지 Vol.15 No.3

Si계 음극소재는 리튬 삽입-탈착 중 일어나는 큰 구조적 부피변화와 입도변화로 인해 빠른 성능 퇴화가 일어나는 단점이 있다. 산화물 SiO 음극소재는 리튬과의 반응 중 비활성상인 $Li_2O$ 및 lithium silicate가 형성되어 Si의 부피변화를 완화시키는 버퍼 역할을 하므로 용량은 Si보다 적으나 개선된 용량 유지 특성을 보이는 것으로 알려져 있다. 본 연구에서는 Si의 부피변화 완화를 위하여 저가의 $SiO_2$와 입자간 전기전도성을 향상시키는 흑연을 구조안정화 기재로서 사용하여 Si-$SiO_2$-흑연 복합재 음극을 제작하였다. 구조안정화 뿐만 아니라 silane계 전해액 첨가제를 이용하여 Si-$SiO_2$-흑연 복합재 음극과 전해액간 계면을 안정화시킴으로써 용량 유지 특성이 개선되는 효과에 대해 보고하고자 한다. Structural volume change occurring on the Si-based anode battery materials during alloying/dealloying with lithium is noticed to be a major drawback responsible for a limited cycle life. Silicon monoxide has been reported to show relatively improved cycling performance compared to Si-containing materials for rechargeable lithium batteries, due to the structural buffering role of in-situ formed $Li_2O$ and lithium silicate during the reaction of silicon monoxide and lithium. Here we report improved cycling ability of interfacially stabilized Si-$SiO_2$-graphite composite anode using silane-based electrolyte additive for rechargeable lithium batteries, which includes low cost silicon dioxide for structural stabilization and graphite for enhanced conductivity.

Self-organized Artificial SEI for Improving the Cycling Ability of Silicon-based Battery Anode Materials

민정혜,배영산,Joong-Yeon Kim,김성수,송승완 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.4

스타일 전이 기술의 사용성 향상을 위한 attention map 기반 모델 최적화

민정혜 한국컴퓨터정보학회 2023 韓國컴퓨터情報學會論文誌 Vol.28 No.8

Style transfer is one of deep learning-based image processing techniques that has been actively researched recently. These research efforts have led to significant improvements in the quality of result images. Style transfer is a technology that takes a content image and a style image as inputs and generates a transformed result image by applying the characteristics of the style image to the content image. It is becoming increasingly important in exploiting the diversity of digital content. To improve the usability of style transfer technology, ensuring stable performance is crucial. Recently, in the field of natural language processing, the concept of Transformers has been actively utilized. Attention maps, which forms the basis of Transformers, is also being actively applied and researched in the development of style transfer techniques. In this paper, we analyze the representative techniques SANet and AdaAttN and propose a novel attention map-based structure which can generate improved style transfer results. The results demonstrate that the proposed technique effectively preserves the structure of the content image while applying the characteristics of the style image.

간접 효소 면역측정법을 이용한 입원 환아의 대변에서 바이러스 항원의 검출과 임상적 의의

민정혜,서정완,박혜경,Min, Jung Hye,Seo, Jeong Wan,Park, Hye Kyung 대한소아소화기영양학회 2004 Pediatric gastroenterology, hepatology & nutrition Vol.7 No.2

목적: 급성 설사로 입원한 소아의 대변 검체에서 rotavirus, adenovirus, astrovirus, calicivirus 및 enterovirus의 바이러스 항원을 검출하고 임상 증상과의 연관성을 알기 위해 본 연구를 시도하였다. 방법: 이화여자대학교 의과대학 목동병원 소아과에 1996년 3월부터 1999년 12월 사이에 입원하였던 소아 74명의 대변을 채취하였는데, 53개는 급성 설사 환자에서 채취하여 이를 설사군으로, 21개는 동일시기에 설사가 없는 타질환으로 입원한 소아에서 무작위로 채취하여 이는 대조군으로 분류하였다. 대변 검체는 영하 $20^{\circ}C$에서 냉동 보관 후 단클론 항체를 이용한 간접 효소 면역측정법으로 바이러스 항원 검출을 하였고 각 바이러스 검출과 임상 증상을 비교하였다. 결과: 바이러스 항원은 설사군에서 46례와 대조군에서 14례 검출되었다. 이 중 enterovirus 47례, rotavirus 26례, adenovirus 16례, astrovirus 11례, 그리고 calicivirus가 11례 검출되었다. 시기적으로 바이러스 항원은 봄(3>5월)에 많이 검출되었다(63%). 하나의 바이러스 항원이 검출된 경우는 설사군 22례, 대조군 6례로 모두 28례이었다. 바이러스 항원이 동시 검출된 경우는 30례이며, Salmonella group B와 enterovirus의 동시 감염 2례 있었다. 여러 항원이 검출된 30례를 세분하면, 두 종류의 바이러스가 검출된 경우가 15례, 세 종류의 바이러스가 검출된 경우가 11례, 네 종류의 바이러스가 검출된 경우가 2례, 다섯 종류의 바이러스가 모두 검출된 경우도 2례 있었다. 대변에서 바이러스 항원이 동시 검출된 다중성이나 종류에 따른 임상 증상의 차이는 없었다. 결론: 본 연구에서는 대변 내 바이러스 항원에 대한 단클론 항체를 이용한 간접 효소 면역측정법으로 검사하였으며, 각 바이러스 항원과 임상 증상과의 연관성은 없었다. 앞으로 더 많은 소아를 대상으로 역전사 중합효소 연쇄반응, 바이러스 배양 검사 등으로 다양하게 검사하여 소아 설사의 바이러스성 원인과 역학이 연구되어야 할 것이다. Purpose: The purpose of this study is to detect viral coproantigens in children who were hospitalized with acute diarrhea and to compare its association with clinical symptoms. Methods: Seventy-four stool samples were collected from children admitted to Ewha Mokdong Hospital from March 1996 to December 1999. The samples were frozen and analyzed for rotavirus, adenovirus, enterovirus, astrovirus, and calicivirus by enzyme immunoassay (EIA) with monoclonal antibody. 53 stool samples were collected from patients with diarrhea (diarrheal group) and 21 stool samples from patients hospitalized for reasons other than diarrhea (control group). Clinical features and laboratory findings were reviewed in both groups. Results: Among 74 stool samples, virus antigens were detected in 60 samples. Of the 60 virus-positive stool samples, 47 enterovirus, 26 rotavirus, 16 adenovirus, 11 astrovirus, and 11 calicivirus antigens were detected by EIA. Of the 60 virus-positive stool samples, 28 samples have one viral antigen, 30 samples have 2 or more viral antigens, and 2 samples showed a simultaneous infection of Salmonella group B and enterovirus. There was no relationship between the detected virus and clinical features. Conclusion: In this study, viral coproantigen and clinical symptoms were not associated. In the future, further larger scale studies are necessary.

Romey 분석법에 의한 2009와 2015 개정 과학과 교육과정의 생명과학Ⅰ 탐구 경향성 비교 분석

민정혜,심재호 한국생물교육학회 2020 생물교육 Vol.48 No.3

The purpose of this study was to find out how the inquiry tendency in Life Science Ⅰ textbooks changed according to the 2009 and 2015 revised science curriculum. To this end, we compared to 10 Life Science Ⅰ textbooks published in 2009 and 2015, using Romey's analysis method. The research results are as follows. First, the sentences, figure materials and chapter summaries of 2009 revised science curriculum's Life Sciences I textbooks showed an authoritarian trend overall, questions and inquiry activities showed an inquiring tendency. Second, the sentences and chapter summaries of the 2015 revised science curriculum's Life Sciences I textbooks showed an authoritarian tendency, figure materials, questions and inquiry activities generally showed an inquiring tendency. Third, the overall inquiry tendency of Life Science I textbooks was slightly improved in the 2015 revision science curriculum compared to 2009. Fourth, it was found that the difference in the inquiry tendency by each unit and component of the textbook was influenced by the author of the unit and the achievement standard presented in the curriculum. The results of this study are expected to be used as basic data to understand the inquisitive teaching that Korea's science education is aiming for.

캐릭터를 현실로: AI 챗봇

민정혜(Junghye Min),김상헌(Sang-Hun Kim),김지민(Ji-Min Kim) 한국컴퓨터정보학회 2023 한국컴퓨터정보학회 학술발표논문집 Vol.31 No.2

한국어 발음 훈련을 위한 음성 인식 웹 사이트 - 바름

민정혜(Junghye Min),강교진(Gyo Jin Kang),김인기(In Gi Kim) 한국컴퓨터정보학회 2023 한국컴퓨터정보학회 학술발표논문집 Vol.31 No.2

여자고등학생의 월경기 자가관리 교육 프로그램의 효과

민정혜 ( Min Jeonghye ),안숙희 ( Ahn Sukhee ) 여성건강간호학회 2018 여성건강간호학회지 Vol.24 No.3

Purpose: To examine the effect of menstrual self-management education program on knowledge and behavior of menstrual self-management in high school girls. Methods: With a randomized controlled trial, 100 high school girl students were randomly assigned into experimental group and control group. Menstruation self-management program was consisted of a total of four sessions of education program (1 hour of education per session). Control group only received the first class of education. Measurement tools were 20-item menstrual knowledge scale and 12-item women’s genito-urinary hygiene scale. Pretest and post-test questionnaires were administered. Results: There were significant differences in menstrual knowledge as well as menstrual self-management behavior between the two groups. The experimental group showed significant improvement in both menstrual knowledge score (t=13.37, p<.001) and menstrual self-management behavior score (t=8.38, p<.001) than the control group. Conclusion: Results of this study suggest that the monthly self-management education program is effective in increasing the knowledge of menstruation of female high school students and enhancing their performance. This program needs to be implemented as a part of high school’s standard sex education. Further study is needed to analyze follow-up effects of the program on self-management behavior of students after at least one menstrual cycle.

공공데이터 기반의 나들이 경로 추천 시스템

민정혜(JungHye Min),강교진(Gyo Jin Kang),김인기(In Gi Kim),백태민(TaeMin Baek) 한국컴퓨터정보학회 2023 한국컴퓨터정보학회 학술발표논문집 Vol.31 No.1

시계열과 비 시계열 데이터를 이용한 주식 가격 예측의 비교

송민섭,민정혜 한국컴퓨터정보학회 2023 韓國컴퓨터情報學會論文誌 Vol.28 No.8

Stock price prediction is an important topic extensively discussed in the financial market, but it is considered a challenging subject due to numerous factors that can influence it. In this research, performance was compared and analyzed by applying time series prediction models (LSTM, GRU) and non-time series prediction models (RF, SVR, KNN, LGBM) that do not take into account the temporal dependence of data into stock price prediction. In addition, various data such as stock price data, technical indicators, financial statements indicators, buy sell indicators, short selling, and foreign indicators were combined to find optimal predictors and analyze major factors affecting stock price prediction by industry. Through the hyperparameter optimization process, the process of improving the prediction performance for each algorithm was also conducted to analyze the factors affecting the performance. As a result of feature selection and hyperparameter optimization, it was found that the forecast accuracy of the time series prediction algorithm GRU and LSTM+GRU was the highest.