Flexible high-energy Li-ion batteries with fast-charging capability.

Park, Mi-Hee,Noh, Mijung,Lee, Sanghan,Ko, Minseong,Chae, Sujong,Sim, Soojin,Choi, Sinho,Kim, Hyejung,Nam, Haisol,Park, Soojin,Cho, Jaephil American Chemical Society 2014 NANO LETTERS Vol.14 No.7

<P>With the development of flexible mobile devices, flexible Li-ion batteries have naturally received much attention. Previously, all reported flexible components have had shortcomings related to power and energy performance. In this research, in order to overcome these problems while maintaining the flexibility, honeycomb-patterned Cu and Al materials were used as current collectors to achieve maximum adhesion in the electrodes. In addition, to increase the energy and power multishelled LiNi0.75Co0.11Mn0.14O2 particles consisting of nanoscale V2O5 and LixV2O5 coating layers and a LiδNi0.75-zCo0.11Mn0.14VzO2 doping layer were used as the cathode-anode composite (denoted as PNG-AES) consisting of amorphous Si nanoparticles (<20 nm) loaded on expanded graphite (10 wt %) and natural graphite (85 wt %). Li-ion cells with these three elements (cathode, anode, and current collector) exhibited excellent power and energy performance along with stable cycling stability up to 200 cycles in an in situ bending test.</P>

Study on the Curriculum of Korean Optometrist Training Institutes

Mijung Park,Jae-Myoung Seo 대한시과학회 2017 대한시과학회지 Vol.19 No.4

목적: 전국의 대학 교육과정과 교과목의 중요도를 비교 분석하고 현장에서 이루어지는 현장실습 관련 실 태를 파악하여 한국 안경광학과의 교육과정의 현 주소를 짚어보고자 한다. 방법: 설문지는 안경광학과가 개설되어 있는 4년제 15개, 3년제 28개, 2년제 2개 대학 모두 45개 대학 그리고 전국의 각 지역별 현장의 안경사 522명을 대상으로 2016년 6월부터 7월까지 대면 및 우편을 통하여 배포 및 실시하였다. 설문항목은 각 대학에서 개설된 교과목명과 그에 대한 중요도, 현장실습 교과목 운영 방식에 주안점을 두어 작성했다. 결과: 전국의 안경광학과에서 개설되어 있는 교과목의 중요도 지수는 시광학이론 과목이 4.1, 시광학응 용/실무 과목이 7.1로 나타나 시광학이론 과목 : 시광학응용/실무 과목의 비율은 1 : 1.7의 비율로 나타났다. 3년 또는 4년 과정으로 학제가 이루어진 대부분의 대학의 임상실습 교과에서 평균 270시간 정도의 실습을 하는 것으로 나타났다. 결론: 현장중심 교육의 확대와 졸업 후 갖추어야 할 능력배양을 강하게 요구하는 사회적 요구와 더불어 최근 빠르게 변화하는 산업적 변화에 따른 직업적 지각 변동을 고려하여 미래 안경사에 적합한 학제와 교육 과정 구조를 개발해야 할 것으로 생각된다. Purpose: This study aimed to investigate the current state of Optometry program in Korea by analyzing the relative importance of curriculum and the clinical practice. Methods: A self-reported questionnaire was administered at the 45 Optician training institutes (2 two-year colleges, 28 three-year colleges, 15 four-year Universities) and by 522 clinical Opticians all across the country from June to July 2016. It consists of the subjects entitled by each institutes, their important rate and the way to operation method. Results: The quotients of importance in terms of the theory and the application of vision science were 4.1 and 7.1, respectively. The ratio of the theory to the application of vision science was at 1.7. The subject entitled clinical practice was taught in institutes except for two-year college for about 270 hours in average. Conclusions: Considering the extension of field center education, the social needs for the better qualification from graduate and the recent industrial evolution, it needs to develop the new structure of curriculum for future Optician.

The Cognition, Balance, and Quality of Life in the Elderly

Mijung Park 한국간호과학회 2011 한국간호과학회 학술대회 Vol.2011 No.10

Correlation between the actual sleep time 24 hours prior to an examination and the time to achieve chloral hydrate sedation in pediatric patients in South Korea: a prospective cohort study

Mijung Park,Ji Um,So Hyun Kim,Jiseon Yoon,Yeonjae Lee,Jiyeong Kwon,Seonhee Baek,Dong Yeon Kim 한국아동간호학회 2023 Child Health Nursing Research Vol.29 No.1

Purpose: This study investigated correlations between the actual sleep time 24 hours prior to an examination and the time to achieve chloral hydrate sedation in pediatric patients. Methods: With parental consent, 84 children who were placed under moderate or deep sedation with chloral hydrate for examinations from November 19, 2020 to July 9, 2022 were recruited. Results: Patients' average age was 19.9 months. Pediatric neurology patients and those who underwent electroencephalography took significantly longer to achieve sedation with chloral hydrate. There was a negative correlation between the time to achieve sedation and actual sleep time within 24 hours prior to the examination. Positive correlations were found between the actual sleep time 24 hoursprior to the examination and the second dose per weight, as well as between the sedation recovery time and awake hours before the examination. Conclusion: Sleep restriction is not an effective adjuvant therapy for chloral hydrate sedation in children, and sedation effects vary according to pediatric patients' characteristics. Therefore, it would be possible to reduce the unnecessary efforts of caregivers who restrict children's sleep for examinations. It is more important to educate parents about safe sedation than about sleep restriction.

Mercury Ion Monitoring in Mercury Plating Bath by Anodic Stripping Voltammetry

Park, Mijung,Yoon, Sumi,Shin, Woonsup The Korean Electrochemical Society 2016 Journal of electrochemical science and technology Vol.7 No.3

Anodic stripping voltammetry (ASV) is successfully applied in mM level detection of mercury ion in an electroplating bath which is currently used in preparing a cathodic electrolyzer. Glassy carbon electrode is used for the detection and the optimum condition obtained is 10 s deposition at −1.4 V vs. Ag/AgCl and stripping by scanning from −1.4 to +0.4 V vs Ag/AgCl at 50 mV/s. By applying the method, the mercury ion concentration in the electroplating bath could be successfully monitored during the plating.

수 종 상황버섯의 조다당 분획물 조성

박미정(Mijung Park),안미정(Mi-Jeong Ahn),김진웅(Jinwoong Kim),제금련(Keum Ryon Ze),이흠숙(Heum Sook Lee) 한국식품영양과학회 2007 한국식품영양과학회지 Vol.36 No.1

본 연구는 국내에서 재배되거나 수입되어 유통되는 4종 Phellinus 속 버섯(구멍쟁이버섯과)의 조다당 분획물의 조성을 비교함으로써 각 종간의 차이에 의한 성분조성의 차이를 검토하기 위하여 수행되었다. 상황버섯의 활성 분획 중의한 유효성분인 조다당 분획물을 에탄올 냉침법으로 제조한 결과, 조다당 분획물의 취득률은 P. linteus 15.0%, P. baumii 5.1%, P. pini 6.3%, P. igniarius 5.7%로 Phellinus 종에 따라 차이가 있었다. 또한, 그 다당체를 조성하고 있는 단당의 함유량도 버섯의 종에 따라 큰 차이를 보였다. 즉, P. linteus의 경우, 건조중량 1 g 당 함유된 당의 총량은 148.713 ㎎/g이었으나, P. baumii는 29.022 ㎎/g, P. pini는 29.222 ㎎/g으로 P. lintues의 약 1/5 정도의 당 함유량을 나타냈으며, P. igniarius는 P. lintues의 1/100 정도인 1.546 mg/g의 당을 함유하고 있었다. 모든 Phellinus 속 버섯에서 glucose의 함량이 월등하게 많았으며, 함유되어 있는 각 단당들의 절대량은 종에 따라 차이가 있었다. P. linteus는 mannose와 ribose가 P. baumii와 P. pini보다 적은 양이 함유되어 있는 것을 제외하고는 그 외의 모든 단당을 월등하게 많이 함유하고 있었다. P. baumii와 P. pini는 arabinose를 제외하고는 거의 모든 단당의 함량이 유사하였다. P. igniarius는 거의 모든 당의 절대량이 다른 Phellinus 속 버섯에 비하여 매우 적었다. Various Phellinus species (Hymenochaetaceae) including P. linteus, P. baumii, P. pini, and P. igniarius of domestic and foreign products, were examined by gas chromatography to validate their composition of crude polysaccharides. The crude polysaccharide fraction, which is known to be one of the physiologically active fractions, were prepared by a cold ethanol precipitation method and the yield of the crude polysaccharide fractions of P. linteus, P. baumii, P. pini, and P. igniarius were 15.0%, 5.1%, 6.3% and 5.7%, respectively. The total monosaccharide amount of the crude polysaccharide fraction of P. linteus was 148.713 ㎎/g (dry weight of mushroom) while those of P. baumii, P. pini and P. igniarius were 29.022 ㎎/g, 29.222 ㎎/g and 1.546 ㎎/g, respectively. Although the major monosaccharide of all Phellinus mushrooms was glucose, there were remarkable differences in the absolute quantity of each monosaccharide. P. linteus included plenty of monosaccharides except mannose and ribose in comparison with P. baumii and P. pini. The absolute quantities of monosaccharides of P. baumii and P. pini were nearly similar except arabinose. The total monosaccharides of P. igniarius were minimal, but the portions of galactose and mannose in P. igniarius were greater than in the other species.

에듀테인먼트를 이용한 모바일 학습 컨텐츠 개발

박미정 ( Mijung Park ),안치현 ( Chi-hyun Ahn ),우종정 ( Jongjung Woo ) 한국정보처리학회 2007 한국정보처리학회 학술대회논문집 Vol.14 No.1

국내에서 통신 산업과 게임 산업은 다른 기술 산업 분야에 비해 급격하게 성장 하였으며, 현재 국내 산업 분야에서 큰 부분을 차지하고 있다. 통신과 게임 산업의 성장은 교육 분야에 새로운 학습 컨텐츠를 요구하고 있다. 그에 따라 모바일 기기를 이용한 컨텐츠 개발이 이루어 졌으나 통신비용이 높고 학습자의 흥미유발을 고려하지 않았다. 따라서 본 논문은 소켓 통신을 사용하여 요금을 절감하고, 학습자가 흥미롭게 학습 할 수 있도록 에듀테인먼트 요소를 적용한 휴대폰 기기용 학습 컨텐츠를 제안한다.

Electroacupuncture ameliorates poloxamer 407-induced hyperlipidemia through suppressing hepatic SREBP-2 expression in rats

Yeom, Mijung,Park, Jinhee,Lee, Bombi,Lee, Hyang Sook,Park, Hi-Joon,Won, Ran,Lee, Hyejung,Hahm, Dae-Hyun Elsevier 2018 Life sciences Vol.203 No.-

<P><B>Abstract</B></P> <P><B>Aims</B></P> <P>Acupuncture, particularly electroacupuncture (EA) has been shown to have the lipid-lowering effects, but not completely investigated. The present study was aimed to examine whether EA could attenuate poloxamer-407 (P-407)-induced hyperlipidemia in the rats and to investigate its potential mechanisms.</P> <P><B>Main methods</B></P> <P>Rats received P-407 (0.4 g/kg, i.p.) to induce hyperlipidemia. EA was performed at ST36 and ST40 acupoints a total of three times with 12 h-interval starting 1 h before the P-407 injection at 0.6 mA intensity and 2 Hz frequency for 10 min.</P> <P><B>Key findings</B></P> <P>In P-407-induced hyperlipidemic rats, EA stimulation at ST36 and ST40 acupoints significantly lowered the serum levels of triglycerides, total cholesterol, LDL-cholesterol and atherogenic index, while markedly increasing the serum HDL-cholesterol levels. Meanwhile, hyperlipidemic rats had significantly higher expression of sterol regulatory element-binding protein (SREBP)-2, without any difference in SREBP-1 expression in the liver, as compared with normal ones. EA significantly attenuated the expression of SREBP-2 with a subsequent decrease in 3-hydroxy-3-methylglutaryl coenzyme A reductase and an increase in low-density lipoprotein receptor at both mRNA and protein levels in the liver of hyperlipidemic rats. These changes did not occur after electrical stimulation at a non-acupoint.</P> <P><B>Significance</B></P> <P>Taken together, our findings indicate that EA stimulation to P-407-induced hyperlipidemic rats improves the lipid abnormalities, which may be associated with regulation of the expression of key enzymes of cholesterol synthesis in the liver through modulation of SREBP-2.</P>

금속 폼 기공구조와 압력강하특성 간의 상관관계에 관한 연구

박미정(Mijung Park),윤병규(Byoungkyu Yun),이정민(Jeongmin Lee) 한국자동차공학회 2011 한국자동차공학회 학술대회 및 전시회 Vol.2011 No.11

Metal foam has been developed by Alantum Corp. and used as DPF filter media and catalyst substrate. 3 dimensional open pore structure of metal foam gives large specific surface area and high porosity thereby higher gas conversion rate and lower pressure drop compared with typical ceramic and metal filter media. In order to understand the pressure drop caused by metal foam pore structure, serial flow bench tests and pore structural properties measurements have been conducted. In this study, modification of previously presented pressure drop correlation has been performed based on porosity and specific surface area of metal foam.

아연제련공정의 전력저감을 위한 불용성 MMO 전극 적용 특성에 관한 연구

박미정(Mijung Park),이택순(Taeksoon Lee) 대한환경공학회 2020 대한환경공학회지 Vol.42 No.9

목적 : 에너지 다소비 산업인 전해 제련 산업분야의 에너지 사용 절감을 위하여 현재 사용 중인 Pb+Ag합금 전극과 불용성 복합 금속산화물(MMO, Mixed Metal Oxide) 전극 전력 사용량을 비교 연구를 하였다. 방법 : 실제 현장 아연 제련액과 ZnSO₄ 모사액을 제조하여 전류밀도 500 A/m² 조건에서 전극의 과전압, 전압, 아연석출 효율, 수명 특성을 연구 평가하였다. 결과 및 토의 : 불용성 MMO 전극의 과전압은 28.9% 더 낮고 전압은 최소 12.5% 더 낮았다. 효율은 실제 현장 아연 제련액은 1.93% 정도 높았으며, 모사액은 6.3% 정도 높았다. 사용 중인 Pb+Ag합금 전극과 비교 시 불용성 MMO 전극이 과전압이 낮고 전압특성이 양호하며 높은 전류효율 특성을 나타내었다. 결론 : Pb+Ag합금 전극과 불용성 MMO 전극의 전력소비량을 비교・평가한 결과 불용성 MMO 전극 전력 소비량이 실제 현장 아연 제련액은 17%, ZnSO₄ 모사액은 23.8% 낮음을 알 수 있었다. Objective : The zinc electrowinning industry is one of the high energy consumption industries where energy saving is required. In the zinc electrowining process, electrode is a high energy consuming part. In order to reduce energy use in the electrolytic smelting industry, a comparative study was conducted on the current usage of Pb+Ag alloy electrode and insoluble composite metal oxide (MMO) electrode. Methods : In this study, a comparative evaluation of energy consumption was conducted between the generally used Pb+Ag alloy electrode and an insoluble MMO electrode. Aluminum was used as a reducing electrode. The actual on-site zinc electrowinning solution and ZnSO₄ simulated solution were prepared to estimate the electrode potential, voltage, zinc deposition efficiency, and lifetime characteristics under the current density of 500 A/m². Results and Discussion : The overvoltage of the insoluble MMO electrode was 28.9% lower and the voltage was 15.0% l o wer than that of Pb+Ag alloy electrode. The zinc deposition efficiency of the insoluble MMO electrode was higher 1.9% in the actual on-site zinc electrowinning solution and 6.3% in the simulated solution. Compared with the Pb+Ag alloy electrode in use, the insoluble composite metal oxide electrode exhibited low overvoltage, good voltage characteristics, and high current efficiency characteristics. Conclusions : When the energy consumption of the Pb+Ag alloy and the insoluble MMO electrodes was compared, The insoluble MMO electrode showed 17.0% lower energy consumption in the actual on-site zinc electrowinning solution and 23.8% lower in the ZnSO₄ simulated solution than Pb+Ag alloy electrode.