• Title/Summary/Keyword: $I_2$-convergence

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Dependence of Thermal and Electrochemical Properties of ceramic Coated Separators on the Ceramic Particle Size (알루미나 크기에 따른 세라믹 코팅 분리막의 열적 특성 및 전기화학적 특성)

  • Park, Sun Min;Yu, Ho Jun;Kim, Kwang Hyun;Kang, Yun Chan;Cho, Won Il
    • Journal of the Korean Electrochemical Society
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    • v.20 no.2
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    • pp.27-33
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    • 2017
  • Conventional lithium ion batteries suffer from notorious safety issues caused by inevitable lithium dendrite formation and proliferation during over/fast charging processes. The lithium dendrites or mechanical damage on the separator induce internal short circuit in LiB that generates extensive amount of heat within contacted electrode surfaces through the separator. During this heat generation, conventional polyolefin separators shrinks dramatically, and increasing short circuit pathway, that causes the battery to explode. To overcome this serious issue, ceramic coated separators are developed in commercial LiB to enhance thermal and mechanical stability. In this paper, various size(IL = 488.5 nm, I = 538.7 nm, S = 810.3 nm, D = 1533.3 nm) of $Al_2O_3$ particles are coated using styrene-butadiene rubber(SBR) / carboxymethyl cellulose(CMC) binder on PE separator to investigate its thermal stability and electrochemical effect on LiB coin cell with NCM cathode and Li metal anode.

The Effects of Design Thinking in High School Chemistry Classes (디자인씽킹 기반 고등학교 화학 수업의 효과 연구)

  • Yang, Heesun;Kim, Mi-Yong;Kang, Seong-Joo
    • Journal of the Korean Chemical Society
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    • v.64 no.3
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    • pp.159-174
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    • 2020
  • The purpose of this study is to examine 'Design Thinking' based Chemistry Class program as an education strategy for core competence of creative convergence talent. The program stages were modified and supplemented into eight stages, including 'Knowledge Understand', 'Empathy', 'Sharing perspective', 'Ideate', '1st Prototype', '1st Test', '2nd Prototype', and '2nd Test', so that the 'Design Thinking Process in Science Education' can be applied to the chemistry class. Considering the linkage between the 2015 and 2009 revised national curriculum, the achievement criteria were selected, and the lesson plans and student activity sheet were developed according to the themes to be met. Four thematic educational programs were developed and applied to Chemistry I for the second grade of high school students from March to August. The results were verified through qualitative data analysis of the class scene and pre- and post-test based on inventories of 'Empathy' 'STEAM educational competence', 'Problem solving process'. As a result of applying the developed program, 'empathy' showed a significant improvement in empathy with others and empathy with the problem situation. In 'STEAM educational competence', there was a significant enhancement in science and design competence. In the 'problem finding process', the problem definition, problem solution design, and problem-solving review were significantly improved in the 'problem-solving process'. The results of this study provided implications for the applicability of design thinking - based chemistry classes and its educational effect.

Investigation of Factors Contributing to Childhood Soft-Tissue Injuries in the Face (소아의 안면 연부조직 손상에 관한 연구)

  • Sim, Mi-Jung;Sohn, In-A
    • Journal of Digital Convergence
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    • v.11 no.8
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    • pp.219-225
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    • 2013
  • The purpose of this study was to retrospectively investigate the contributing factors in facial soft tissue injuries among children. A record-based analysis was carried out on 126 patients with facial lacerations who visited I hospital in the dept of plastic surgery from April 2010 to May 2011. Through all age group showed a significant difference in incidence rate for male and female.(p<.05). Overall, 49% of injuries occurred outdoors and the most frequent cause of injury was slip-down (42%), followed by being struck (40%). In general, the frequency of injuries peaked summer(30.2%) and increased between 12pm and 4pm. 105 patients (83.3%) arrived at the emergency room within an hour. The forehead(26%) was the most commonly injured area. The depth of soft tissue injuries was mostly subcutaneous(54%), and 1~2cm was the length of injury with the highest incidence(46%). Most children (40%) needed local anesthesia and only 4 children (1.53%) suffered associated fractures. Facial injuries require special attention because of their potential threat in inducing permanent scar or disfigurement. For the safety of children, the preventive measures to reduce facial soft tissue injuries must be improved.

An Analysis of the Quality Attributes of Semiconductor Deposition Equipment Using Kano Model: Implications from the Perspective of Complex Products and Systems (CoPS) (카노(Kano) 모델을 활용한 반도체 증착장비 분야 품질 만족 특성 분석: 복합제품시스템(CoPS) 관점에서의 시사점)

  • Lee, Seung Hwan;Kim, Byung-Keun;Ji, Ilyong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.5
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    • pp.28-38
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    • 2020
  • Semiconductor deposition equipment is an important example of Complex Products and Systems (CoPS) and requires in-depth understanding of user requirements. For this reason, we analyzed and compared users' and producers' perspectives on the quality attributes of semiconductor deposition equipment using the Kano model. The results show that the patterns of users' perspectives were different from those of producers. Out of 22 level-2 quality attributes, producers evaluated all 22 attributes as attractive qualities, but users evaluated only 6 as "attractive," 10 as "indifferent," 2 as "must have," and 4 as "other." Although all quality attributes were attractive for producers, only those related to reliability were attractive or must-have qualities, and all others were "indifferent." This result implies that the perspectives on quality attributes may be different between users and producers, and producers should revise their perspectives and strategies. In addition, the results support the characteristics of CoPS suggested by literature implying that performance is more important than economies of scale and cost reduction. It is suggested that producers of semiconductor deposition equipment strategize their approaches to users by considering the characteristics of CoPS.

Development of nature friendly characters for infants and toddlers (영유아를 대상으로 한 자연친화적 캐릭터 개발 연구)

  • Joo, Eun-Ryeong;Chung, Jean-Hun
    • Journal of Digital Convergence
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    • v.16 no.3
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    • pp.415-422
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    • 2018
  • The purpose of this paper is to show development examples of nature-friendly characters and to play a guide role for various nature-friendly characters to appear by presenting nature-friendly characters setting in Korea. Three famous examples of nature-friendly characters in foreign countries and the influence of nature on infants and young children will be examined with reference to previously published papers and published books. I have confirmed that nature harmony positively affects emotions and life respect of infants and young children, the characteristics of nature-friendly characters are 1. The characters are drawn based on nature environment as background. 2. They have been beloved for story of nature conservation and love for nature, and playing in nature environment. As story setting, I suggested 1. A story of forest experience with friends 2. A story of nature observation and exploration such as playing, exploration, and explanation 3. A drawing of Korea nature environment, including grass, flower, tree, insect, etc. 4. An educational and philosophical story of life respect, nature conservation, and love for nature.

Effect of medium sized hospital nurses' nursing intention, infection prevention environment, and social psychological well-being on infection control performance of COVID-19 outbreak (코로나19 발생 상황에서 중소병원 간호사의 코로나19 환자 간호의도, 감염예방환경 및 사회심리적 건강이 코로나 관련 감염관리 수행도에 미치는 영향)

  • Yang Sin Kim;Jae Woo Oh;Seon Ok Kim
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.2
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    • pp.133-141
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    • 2023
  • This study was conducted to identify the effects of medium sized hospital nurses' nursing intention, infection prevention environment, and social psychological well-being on infection control performance of COVID-19 outbreak. The data collection period was from May 2 to May 31, 2022, and the questionnaires of 161 nurses who were working at I and B medium sized hospital in incheon and agree to participate in this study, were analyzed. Using the IBM SPSS/Win 25.0, the collected data was analyzed through the descriptive statistics, t-test, ANOVA, Pearson correlation, and multiple regreβion analysis. As a result, the infection prevention environment(β=.225, p<.001) and the experience of participating in new infectious disease education(β=.208, p=.008) had a significant effect and these variables were found to have 10.9% explanatory power for COVID-19 related infection control performance. Therefore, in the context of the outbreak of COVID-19, it is important to create an environment for infection prevention and to provide continuous and diverse education related to infectius diseases.

Prediction of Pulmonary Function in Patients with Chronic Obstructive Pulmonary Disease: Correlation with Quantitative CT Parameters

  • Hyun Jung Koo;Sang Min Lee;Joon Beom Seo;Sang Min Lee;Namkug Kim;Sang Young Oh;Jae Seung Lee;Yeon-Mok Oh
    • Korean Journal of Radiology
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    • v.20 no.4
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    • pp.683-692
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    • 2019
  • Objective: We aimed to evaluate correlations between computed tomography (CT) parameters and pulmonary function test (PFT) parameters according to disease severity in patients with chronic obstructive pulmonary disease (COPD), and to determine whether CT parameters can be used to predict PFT indices. Materials and Methods: A total of 370 patients with COPD were grouped based on disease severity according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) I-IV criteria. Emphysema index (EI), air-trapping index, and airway parameters such as the square root of wall area of a hypothetical airway with an internal perimeter of 10 mm (Pi10) were measured using automatic segmentation software. Clinical characteristics including PFT results and quantitative CT parameters according to GOLD criteria were compared using ANOVA. The correlations between CT parameters and PFT indices, including the ratio of forced expiratory volume in one second to forced vital capacity (FEV1/FVC) and FEV1, were assessed. To evaluate whether CT parameters can be used to predict PFT indices, multiple linear regression analyses were performed for all patients, Group 1 (GOLD I and II), and Group 2 (GOLD III and IV). Results: Pulmonary function deteriorated with increase in disease severity according to the GOLD criteria (p < 0.001). Parenchymal attenuation parameters were significantly worse in patients with higher GOLD stages (P < 0.001), and Pi10 was highest for patients with GOLD III (4.41 ± 0.94 mm). Airway parameters were nonlinearly correlated with PFT results, and Pi10 demonstrated mild correlation with FEV1/FVC in patients with GOLD II and III (r = 0.16, p = 0.06 and r = 0.21, p = 0.04, respectively). Parenchymal attenuation parameters, airway parameters, EI, and Pi10 were identified as predictors of FEV1/FVC for the entire study sample and for Group 1 (R2 = 0.38 and 0.22, respectively; p < 0.001). However, only parenchymal attenuation parameter, EI, was identified as a predictor of FEV1/FVC for Group 2 (R2 = 0.37, p < 0.001). Similar results were obtained for FEV1. Conclusion: Airway and parenchymal attenuation parameters are independent predictors of pulmonary function in patients with mild COPD, whereas parenchymal attenuation parameters are dominant independent predictors of pulmonary function in patients with severe COPD.

White Mica and Chemical Composition of Samdeok Mo Deposit, Republic of Korea (삼덕 Mo 광상에서 산출되는 백색운모 및 화학조성)

  • Yoo, Bong Chul
    • Journal of the Mineralogical Society of Korea
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    • v.32 no.3
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    • pp.223-234
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    • 2019
  • The geology of the Samdeok Mo deposit consists of Paleozoic Hwajeonri formation, Kowoonri formation, Suchangri formation, Iwonri formation, Hwanggangri formation, Cretaceous, leucocratic porphyritic granite and granitic porphyry. This deposit consists of three quartz veins that filled NS oriented fractured zones in Suchangri formation. Quartz veins vary from 0.05 m to 0.3 m in thickness and extend to about 400 m in strike length. Quartz veins occur as massive, breccia, and cavity textures. Wallrock alteration has silicification, sericitization, argillitization and chloritization. The mineralogy of the quartz veins consists of quartz, fluorite, white mica, biotite, apatite, monazite, rutile, ilmenite, molybdenite, chalcopyrite, Fe-Mg-Mn oxide and Fe oxide. White mica from Samdeok Mo deposit occurs as fine or coarse grains in quartz vein and hostrock and has four mineral assemblages (I type: quartz, molybdenite, Fe oxide and Fe-Mg-Mn oxide, II type: quartz, Fe oxide and Fe-Mg-Mn oxide, III type: quartz and biotite, and IV type: quartz). The structural formular of white mica from quartz vein is $(K_{0.89-0.60}Na_{0.05-0.00}Ca_{0.01-0.00}Sr_{0.02-0.00})_{0.94-0.62}(Al_{1.54-1.12}Mg_{0.36-0.18}Fe_{0.26-0.09}Mn_{0.04-0.00}Ti_{0.02-0.00}Cr_{0.02-0.00}Zn_{0.01-0.00})_{1.91-1.72}(Si_{3.40-3.11}Al_{0.92-0.60})_{4.00}O_{10}(OH_{1.68-1.42}F_{0.58-0.32})_{2.00}$, but white mica of I type has higher FeO content, and lower $SiO_2$ and MgO contents than white micas of other types. Also, compositional variations in white mica from the Samdeok Mo deposit are caused by phengitic or Tschermark substitution ($(Al^{3+})^{VI}+(Al^{3+})^{IV}{\leftrightarrow}(Fe^{2+}{\text{ or }}Mg^{2+})^{VI}+(Si^{4+})^{IV}$) and direct $(Fe^{3+})^{VI}{\leftrightarrow}(Al^{3+})^{VI}$ substitution.

Ways to Restructure Science Elective Courses in Preparation for the High School Credit System and the 2022 Revised Curriculum (고교학점제와 2022 개정 교육과정에 대비한 과학과 선택과목 재구조화 방안 탐색)

  • Lee, Il;Kwak, Youngsun
    • Journal of The Korean Association For Science Education
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    • v.41 no.2
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    • pp.145-154
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    • 2021
  • This study aims to investigate teachers' perceptions of the composition of high school science elective courses ahead of the 2022 curriculum revision, and to derive implications for the organization of the 2022 revised science curriculum in preparation for the full implementation of the high school credit system. To this end, a survey was conducted by randomly sampling high schools across the country. A total of 192 science teachers responded to the questionnaire. In addition, 12 high school science teachers were selected as a focus group, and in-depth interviews were conducted to investigate opinions on the restructuring of elective courses in science. Main research results include 129 (67.2%) science teachers in the survey answered that the current 2015 curriculum's science and elective courses system should be maintained. In the next curriculum, when reconstructing science elective subjects, it is necessary to provide an opportunity to experience the entire contents of each science field through Science I·II system as before, and to ensure student choice in preparation for the credit system. In addition, the opinion that general elective subjects should be organized to include all the contents of science I and II subjects was the highest. Through in-depth interviews, science teachers emphasized that the current science I subject system allows access to the content areas of science as much as possible as the number of subjects is small, and that subjects, such as physics, where the hierarchy of concepts is important, should deal with important content within one subject rather than divided by area. On the other hand, in the current I subject system, there is no subject for liberal arts students to choose from, so teachers suggested that science electives should be organized by subdividing each content area. Based on the research results, the necessity of organizing high school science elective courses in consideration of the purpose of the high school credit system, ways to organize science-convergence elective courses as subjects for all students regardless of career aptitude, ways to organize science-career elective courses, and ways to organize science elective courses in connection with the college admission system were proposed.

The Characteristics of the Anomaly Level and Variability of the Monthly Precipitation in Kyeongnam, Korea (경남지방의 월강수량의 변동율과 Anomaly Level의 출현특성)

  • 박종길;이부용
    • Journal of Environmental Science International
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    • v.2 no.3
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    • pp.179-191
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    • 1993
  • This paper aims to know the characteristics of occurrence of the anomaly level and variability of the monthly precipitation in Kyeongnam, Korea. For this study, it was investigated 주e distribution of the annual and cont비y mean precipitation, the precipitation variability and its annual change, and the characteristics of occurrence of the anomaly level in Kyeongnam area the results were summarized as follows : 1) she mean of annual total precipitation averaged over Kyeongnam area is 1433.3mm. I'he spatial distribution of the annual total precipitation shows that in Kyeongnam area, the high rainfall area locates in the southwest area and south coast and the low rainfall area in an inland area. 2) Monthly mean precipitation in llyeongnam area was the highest in July(266.4mm) 각lowed by August(238.0mm), June(210.2mm) in descending order. In summer season, rainfall was concentrated and accounted for 49.9 percent of the annual total precipitation. Because convergence of the warm and humid southwest current which was influenced by Changma and typhoon took place well in this area. 3) The patterns of annual change of precipitaion variability can be divided into two types; One is a coast type and the other an inland type. The variability of precipitation generally appears low in spring and summer season and high in autumn and winter season. This is in accord with the large and small of precipitation. 4) The high frequency of anomaly level was N( Normal)-level and the next was LN( Low Informal) -level and 25(Extremely Subnormal)-level was not appeared in all stations. The occurrence frequency of N level was high in high rainfall area and distinguish성 in spring and summer season but the low rainfall area was not. hey Words : anomaly level, variability, precipitation, coast type, inland type.

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