• Journal of Advanced Marine Engineering and Technology
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• 제22권1호
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• pp.108-116
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• 1998

In this paper it is investigated the roles of key elementary reactions for NO formation in methane-air one-dimensional premixed flame and counterflow diffusion flame, which were studied numerically by using NO kinetics and $C_{2}$ -chemistry complied by Miller and Bowman. The spatial distributions of the reaction rates of 9 main elementary reactions directly related to NO formation and destruction were calculated. Integration of the rates of all reactions in the NO formation across the flame yields the quantitative reaction path diagram, which shows clearly relative importance of each reaction path in NO formation and how it changes with the type and parameters of the flame. The results show that the thermal and Fenimore mechanisms are dominant respectively for learn and rich premixed flames, and the latter is dominant for diffusion flames. In addition, it was found that the HCN recycle route is important for diffusion flame, and that the routes of mutual transformation between NO and NO$^{2}$, and between NO and HNO do not contribute to the net NO formation.

• Journal of applied mathematics & informatics
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• 제28권5_6호
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• pp.1545-1552
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• 2010

It is interesting to know the behavior of a network from its structure. One interesting topic is to find a relation between the existence of a positive equilibrium of the reaction network and its structure. One approach to study this topic is using the concept of deficiency. In this work, we develop an algorithm and show an elementary proof of the relation based on the algorithm and deficiency.

• 한국과학교육학회지
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• 제36권6호
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• pp.851-866
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• 2016

본 연구는 초등예비교사를 대상으로 작용 반작용 법칙에 대한 이해 정도와 전형적 인식상황의 조사를 통해 초등예비교사의 '작용과 반작용'에 대한 개념을 알아보는 것을 목적으로 수행하였다. 조사는 초등예비교사 3학년 177명을 대상으로 하였다. 연구 결과, 첫째, 작용 반작용 법칙에 대해 초등예비교사들이 이해하는 정도는 충분하지 않았으며, 상황에 따라 이해의 정도가 달랐다. 둘째, 초등예비교사들은 작용 반작용 법칙과 관련하여 '사람이 벽을 미는 상황'과 같은 일반적인 상황과 함께, '관성에 의한 상황'과 같이 관련이 없는 상황도 전형적으로 떠올리는 경향이 있었다. 또, 작용 반작용의 작용 유형과 결과적인 운동 유형을 다소 편중되게 생각하는 경향이 있었다. 끝으로 이러한 결과를 바탕으로 작용 반작용 법칙에 대한 이해 제고와 관련하여 몇 가지 제언을 하였다.

• Korean Chemical Engineering Research
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• 제46권2호
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• pp.301-309
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• 2008

본 연구에서는 레졸수지 합성에서 부가반응 실험변수인 F/P 몰비, 촉매 wt% 및 반응온도가 페놀치환체에 미치는 영향을 2단 실험계획법을 사용하여 실험하고 실험 결과를 삼원변량분석법(ANOVA, SPSS)을 사용하여 해석하였다. 페놀치환체는 반응시간 300분에서 F/P 몰비가 높을수록, 반응온도가 낮을수록, 촉매량이 적을수록 증가하는 경향을 보였고 ortho 지향성이 있음을 확인하였다. 레졸형 페놀수지의 합성에서 페놀계 치환체의 해리반응과 메틸렌글리콜 형태의 포름알데하이드의 분율을 고려하는 Zavitsas류의 속도론 모델을 단순화시킨 기초반응 모델을 제시하고 Zavitsas류의 속도론 모델과 비교하였다. 기초반응 모델은 평균적으로 2.79%의 오차를 보였으며 Zavitsas류 모델의 오차인 3.27%와 비슷한 값을 보이는 것을 확인하였다. 따라서 본 논문에서 제시한 기초반응 모델은 레졸합성의 부가반응 속도론 연구에 적용 가능하다고 판단된다.

• 초등상담연구
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• 제9권1호
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• pp.1-20
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• 2010

본 연구는 초등학교 고학년(4, 5, 6) 학생들을 대상으로 성별에 따른 KSD 반응의 차이와 사회성측정에 의한 5가지 지위의 유형별로 KSD 반응이 다르게 나타날 것이라는 가설에 근거하여 진행된 연구였으며, 동시에 KSD 반응이 사회성측정의 지위 유형을 어느 정도 판별하는지를 확인하는 연구였다. A시에 소재한 4학년 5학급, 5학년 5학급, 6학년 10학급으로 총 20개의 학급에 대하여 안이환(2007)이 개발한 사회성측정과 Burns와 Kaufman(1970)의 KSD를 실시하였다. 피검자의 수는 총 366명이었으며 엄밀한 형태의 층화군집표본 추출법은 아니었다. 3개의 가설을 검증하기 위하여 차례대로 독립표본 t 검증, 일원변량분석, 판별분석법이 사용되었다. 그 결과, 성별에 따른 KSD 반응의 3요인 가운데 인물상의 행위, 인물상의 특징에서 통계적으로 유의미한 차이가 있는 것으로 나타났지만 역동성 요인에서는 유의미한 차이가 나타나지 않았다. 또한, 일원변량분석의 결과 여학생의 KSD 반응 가운데 인물상의 특징 및 역동성 요인에서는 통계적으로 유의미한 차이가 나타났지만 인물상의 행위 요인에서는 유의미한 차이가 나타나지 않았다. 따라서 KSD 반응 가운데 인물상의 특징이 남녀에 대한 구분 및 사회성측정의 지위 유형과 깊이 관련되어 있음을 알 수 있었다. 본 연구의 결과로 볼 때, 田中志帆(전중지범)(2009)이 제안한 KSD 채점체계 영역에 대한 검토의 필요성 이 제기되었다. 마지막으로, KSD 반응이 사회성측정을 잘 판별하지 못하는 것으로 나타났지만 사회성측정을 보완하는 도구로서의 투사적 그림검사에 대한 새로운 접근법이 필요하였다.

• Korean Chemical Engineering Research
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• 제47권3호
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• pp.380-385
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• 2009

평판형 교반기를 사용하여 2-amino-2-methyl-1-propanol(AMP)가 용해된 methanol, ethanol, n-propanol, n-butanol, ethylene glycol, propylene glycol, 및 propylene carbonate와 같은 극성 용매에서 이산화탄소($CO_2$)의 흡수속도를 측정하였다. $CO_2$의 흡수속도와 carbamate 생성 반응 메커니즘을 사용하여 기-액 불균일반응계의 빠른 반응영역에서 $CO_2$-AMP의 반응속도론을 해석하였으며 용매의 용해도 매개변수와 반응속도상수와의 상관관계를 제시하였다.

• 한국초등과학교육학회지:초등과학교육
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• 제33권4호
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• pp.784-794
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• 2014

In this study, we operated science teacher learning community to enhance professionality of elementary science teachers. 8 participants with various background, which include their science content knowledge, teaching experience and beliefs about teaching, were involved in this study. Bales(1950)'s social interaction process framework was mainly used to understand the members' interaction, focusing particularly on process aspects not on contents aspects. The data analysis shows that the members in the science teacher learning community tried their best to maintain the positive reaction to other members in most occasions in the community meetings. On the other hand, there were also negative reaction process due to their different ideas and views, causing their emotional conflicts in some social relations and dialogical situations. Nevertheless, the results also imply that the dual reaction processes, which are positive and negative processes, are equally important to facilitate science teachers' professional knowledge and experience. The educational meanings are discussed in the aspects of science teacher education.

• Journal of Advanced Marine Engineering and Technology
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• 제23권1호
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• pp.88-95
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• 1999

This study investigates the effects of different kind fuels on the flame structure by using the numerical simulation in triple flame made by a co-flowing fuels-air stream based on the elementary chemical reaction mechanism. Methane and Hydrogen were used as fuel for this study. In order to interpret the result of the study on numerical simulation Skeletal chemistry is employe as the elementary chemical reaction mechanism for methane Gutheil's as an offset ele-mentary chemical reaction mechanism for hydrogen. The result of this study is as follows. In com-parison between the apparent burning velocity change of triple flame and the one-dimensional pre-mixed flame hydrogen fuel flame is higher than methane fuel flame. The flame thrusts out for-ward in the down stream of the boundary between air-fuel mixture and air stream and a part of the flow is bent and forks out in this protruding flame so that a triple flame is originated.

• 한국환경교육학회지:환경교육
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• 제24권3호
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• pp.18-25
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• 2011

This study was conducted to evaluate the effects of volatile organic compounds and formaldehyde of newly-built school classroom indoor air on the neurobehavioral functions of students. The elementary schools that were opened in September 2008(as of September 2008) was selected for newly-built school and the elementary school that were opened in March 2006 was selected for control group schools. The concentration of formaldehyde(HCHO), a hazardous organic compound that exists in the air of classrooms, exceeded the standard value of $108.2{\mu}g/m^3$ in newly-built schools while it was $60.8{\mu}g/m^3$ in control group schools, which is around 60% of the standard concentration. However, the concentration of the total volatile organic compounds(TVOCs) was $788.9{\mu}g/m^3$ and $756.1{\mu}g/m^3$ in newly-built schools and control group schools respectively, which are approximately two times higher than the standard concentration. In newly-built schools, the mean reaction time of additions and symbol digit, respectively 3,020ms and 2,398ms in pre-exposure were increased to 3,167ms and 2,514ms respectively in post-exposure. The difference of mean reaction time between pre and post exposure was 146.8 ms, or 4.6%, and 116.7ms, or 4.8%, respectively, showing statistically-significant increase of reaction time(p<0.05). On the contrary, the difference of reaction time of both tests were not statistically significant in the control group schools. These results showed that the neurobehavioral performance of newly-built schools students were affected by volatile organic compounds and formaldehyde of classroom indoor air.

• 한국간호교육학회지
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• 제18권1호
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• pp.149-158
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• 2012

Purpose: The purpose of this study was to identify the factors influencing mental health among late elementary age children. Methods: The research design was a secondary data analysis. Data were collected from 746 students in grades 5 or 6, and analyzed using descriptive statistics, t-test, ANOVA, Pearson's correlation coefficients and stepwise multiple regression with the SPSS/PC 18.0 program. Results: The average score of mental health was $3.42{\pm}0.55$. There were significant differences in mental health according to health status, economic status, scholastic performance, relationships with friends, relationships with the teachers, atmosphere of the home, number of siblings and the source of trouble. Stepwise multiple regression analysis showed influencing factors of stress, negative reaction under stress, self-esteem, teacher support, and friend support support and explained 41.4% of total variance in late elementary age children's mental health. Conclusion: These results may contribute to a better understanding of mental health in late elementary age children. The results of the present study indicate a need to develop nursing interventions to prevent and manage elementary school-age children's negative reaction under stress.