• Communications of Mathematical Education
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• v.25 no.3
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• pp.497-524
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• 2011

This study was to understand students' learning about the function of math combined with molecular motions of science using the block scheduling. It was based on the revised Class Structure Model of Lee et al.(2010) where MBL as a tool was used to increase students' participation and understanding in the integrated concepts. The researcher provided the 6th grade students who lived in Sung Nam-Si, Kyung Gi-Do with 8 unit lessons, consisting of 5 stages of CSM. As a result of the study, the integrated education of Mathematics and Science showed synergic effect in studying both subjects and brought a positive result in gradual mathematization. It may be hard to combine all the contents of mathematics and science together. However, learning the relation between volume and pressure, and between volume and temperature of gas used as an example of function shown in our daily life was appropriate through Fogarty's integrated education model because it supported the objective of both subjects. Also, it was a good idea to develop CSM because it was composed of the contents from both subjects held in the same period of a year. Through the five stages, students were able to establish and generalize the definitions and the concepts of function.

• Journal of The Korean Association For Science Education
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• v.43 no.2
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• pp.99-110
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• 2023

In this study, in order to strengthen the AI utilization competency of pre-service secondary science teachers, a project activity in which pre-service teachers directly create an 'AI-based molecular structure customized learning support tool' by using Google's teachable machine was developed and applied. To this end, the program developed for 26 third-grade pre-service teachers enrolled in the Department of Chemistry Education at H University in Chungcheongbuk-do was applied for 14 sessions during extracurricular activities. Then, the perceptions of 'understanding how AI works', 'efficacy of using AI in science classes', and 'plans to utilize AI in science classes' were investigated. As a result of the study, it was found that the program developed in this study was effective in helping pre-service teachers understand the operating principle of AI technology for machine learning at a basic level and learning how to use it. In addition, the program developed in this study was found to be effective in increasing the efficacy of pre-service teachers for the use of AI in science classes. And it was also found that pre-service teachers recognized the aspect of using AI technology as a new teaching·learning strategy and tool that can help students understand science concepts. Accordingly, it was found that the program developed in this study had a positive impact on pre-service teachers' AI utilization competency reinforcement and perception improvement at the basic level. Implications of this were discussed.

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.24-31
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• 2015

효소는 생명 현상을 구현하는 단백질 촉매인데 그 동안 효소의 촉매 반응 속도는 Michaelis-Menten(MM) 모델로 대부분 설명되어 왔다. 그러나 MM 모델은 실험으로 측정된 단일 효소 반응시간의 확률분포 모양을 설명할 수 없다. MM 모델에 반응계수의 정적 무질서 개념을 도입한 효소 반응 모델도 기질 농도에 따라 변화하는 효소 반응시간의 통계적 요동을 설명하지 못한다. 우리는 단일 효소 반응시간의 통계적 요동이 기질에 따라 변화하는 양상을 설명하기 위해 효소 반응을 구성하는 개별 화학반응을 단순히 푸아송 과정이 아닌 갱신과정(renewal process)으로 확장한 효소 반응 모델을 제안한다. 우리는 이 단일 효소 반응 모델과 기질에 따른 효소 반응시간 분산 변화 데이터를 비교하여 효소-기질 복합체의 지속시간 분포를 간단한 형태로 얻어내었다. 또한, 이 정보를 토대로 전산모사를 수행하여 효소 반응시간의 확률분포를 얻어내고, 실제 실험 결과 및 기존 이론들과 비교하였다. 뿐만 아니라 단일 효소 반응시간의 확률분포를 연속 시간 임의의 보행자(continuous time random walker)의 대기시간 확률분포(waiting time distribution)로 대응하면, 평균 제곱 변위가 시간에 따라 단순히 증가 하지 않는 고분자의 특이 수송(anomalous diffusion) 현상도 정량적으로 설명할 수 있었다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.378-381
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• 2011

대표적 가스계 소화약제인 $CO_2$의 소화기구(Extinguishing mechanism)를 재조명하기 위하여, $CH_4$/air 저 신장율 대향류 확산화염을 대상으로 $CO_2$가 소화에 미치는 영향에 대한 수치해석이 수행되었다. 부력이 지배적인 화염의 소화현상은 복사 열손실에 의해 큰 영향을 받기 때문에, 소화농도 예측에 대한 복사모델의 성능평가가 우선적으로 이루어졌다. 주요 결과로서, 공기류에 첨가된 $CO_2$의 소화농도는 복사모델이 고려되지 않은 경우 과다 예측되는 반면에, 간략화된 광학적으로 얇은 근사(Optically thin approximation) 모델과 비교적 높은 정확도를 갖는 좁은 밴드(Statistical narrow band) 모델은 실험의 오차범위 내에서 큰 차이를 보이지 않았다. $CO_2$가 소화에 미치는 순수 희석효과, 희석에 의한 복사효과, 화학적 효과 및 열적효과를 정량적으로 분석하기 위하여 가상의 소화약제의 개념을 도입하였다. 이를 통해 화염의 총괄신장율에 따른 $CO_2$ 소화효과에 대한 구체적인 이해가 시도되었다.

• Life and Agrochemicals
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• v.29 no.10
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• pp.14-17
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• 2008

일반에게 공정한 입장에서 소비자와 커뮤니케이션을 실행하는 수단으로서 "일본농약학회, 지방자치단체, 내각부 식품안전위원회나 농림수산성, 후생노동성 등의 공적기관, 농약공업회나 전국농약협동조합 등 임의단체, 전국농업협동조합이나 전국 판매상 등의 유통업자 등이 실시하는 농약의 안전 사용자 안전 등에 관한 세미나 강습회, 소비자의 간담회", "학회나 농약연구자, 과학리더에 의한 계몽서의 출판, 학회나 업자 단체에 의한 Q&A집의 학회지 게재나 배포". "각종 학회나 공적기관의 홈페이지 계몽 해설문제의 게재", "농약제조 메이커나 임의단체에 의한 인터넷을 통한 메일 잡지 배송", "신문(전국지)를 매개로 한 홍보활동" 등을 들 수 있다. 최근에는 대학에 있어서도 일반사회인(소비자 포함)을 대상으로 한 농약이나 각종 화학물질의 안전성에 관한 공개강좌가 개설되어 있다. 한편 공정한 입장서 농약에 대해서 올바르게 전달한다는 개념에서 출발하지만, 결국엔 상업적 측면이 강한 "재미있고 우습게, 농약이 가지는 잠재적 위험성을 일부러 강조하고, 때로는 과학적 사실과 다른 내용을 의도적 또는 비의도적으로 전달하여 시청자나 독자의 관심을 끌어 시청률이나 발행부수를 신장시키는 것을 목적으로 하는 각종 매스컴으로부터의 막대한 양의 정보발신(모든 매스컴이 해당하는 것은 아님)이 있다. 더욱이 인터넷 사이트에는 종교적 측면이 강한 단체를 포함, 농약의 위험성을 강조하는 일이 있으며 온갖 정보가 넘쳐나고 있다. 물론 공적기관을 포함, 농약의 유용성과 잠재적 위험성에 대하여 공정하고 객관적 입장에서 인터넷을 소개한 정보 발신도 행해지고 있다. "농약은 나쁘고 위험하다"라는 정보로는 센세이셔날 한 상품가치(매스컴측의 보도 메리트)가 있지만 "농약은 안전하고 문제없다"로는 상품가치가 없다고 하는 상업 저널리즘을 드러낸다. "양적으로 압도적인 매스컴 보도"를 뛰어넘어 소비자에게 올바른 정보를 전달, 이해시키는 것은 가능하지 않을까. 다음으로 농약에 관한 리스크커뮤니케이션 수법에 대한 유의점과 과제를 기술한다.

• Membrane Journal
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• v.34 no.1
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• pp.10-19
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• 2024

The bipolar membrane is an ion exchange membrane consisting of a cation exchange layer, an anion exchange layer, and an interface layer, and is a membrane that generates protons and hydroxide ions based on water dissociation characteristics. Using these properties, research is being conducted in various application fields such as the chemical industry, food processing, environmental protection, and energy conversion and storage. This paper investigated the concept of bipolar membrane, water dissociation mechanism, and water dissociation catalyst to provide a comprehensive understanding of bipolar membrane technology, were investigated. Lastly, we also investigated the bipolar membrane process that has been recently applied to energy technology.

• Journal of The Korean Association For Science Education
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• v.31 no.6
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• pp.931-941
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• 2011

This study aimed to examine the effects of argument-based chemistry laboratory investigations using the Science Writing Heuristic (SWH) approach on students' use and embedding of multimodal representations in summary writing. Participants of this study were thirty-nine freshman students majoring in science education at a National University in Korea. Argument-based chemistry laboratory investigations using the SWH approach were implemented for twenty-three students enrolled in one cohort, and the traditional chemistry laboratory teaching was implemented for 16 students enrolled in the other cohort. Summary writing samples were collected from students before and after the implementation. Summary writing samples produced by students were examined using an analysis framework for examining the use and embeddedness of multimodal representations. Summary writing was categorized into one of verbal mode, symbolic mode, and visual mode. With regard to the embedding of multi-modal representations, summary writing samples were analyzed in terms of 'constructing understanding,' 'integrating multiple modes,' 'providing valid claims and evidence,' and 'representing multiple modes.' Data analysis shows that the students of the SWH group were better at utilizing and embedding multimodal representations in summary writing as they provided evidence supporting their claims. This study provides important implications on pre-service science teacher education.

• Journal of the Korean earth science society
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• v.22 no.6
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• pp.469-479
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• 2001

This study investigated the trends in the number of applicants and mean score and applicants’ responses on the test items of Earth Science in the College Scholastic Ability Test (CSAT) implemented for 3 years (1999-2001). The percentage of applicants of science track were 43.14% in 1995, but reduced through 29.5% in 2001 to 26.92% in 2002 CSAT For elective subject, about 22% of science track students applied to Earth Science II which ranked third to Biology II and Chemistry II. In 1999, test items were developed to have the expected difficulty 40 ${\sim}$ 59% (6 items) to 60 ${\sim}$ 79% (10 items). But in 2001 every 16 items were developed to have difficulty 60 ${\sim}$ 79%, which was caused by the policy of so called ‘easy CSAT’. Thus the mean score of ‘Earth Science II’ was increased from 50.26 in 1999 through 64.47 in 2000, to 67.58 in 2001. Applicants were generally very good at solving test items focusing on process skills only and familar items but poor at solving test items related to the motion of the earth and planets and sea wave, especially items calling two or more concepts. Thus special measures to cope with the decrease in applicants of science track should be provided. And it is recommended to develop test items with wider range of difficulty and to reduce test items calling process skills only. And special consideration should be given to teaching the content area with poor achievement and high actual difficulty compared to the expected.

• Journal of the Korean Chemical Society
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• v.57 no.5
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• pp.640-655
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• 2013

The purpose of this study is to analyze the cognitive demands level of the description about 'changes of state' and 'kinetic theory' on the 'science 1' textbooks by the 2007 revised curriculum. The three types of curriculum analysis taxonomy have been used to analyze the cognitive demands level of those contents on the 6 kinds of 'science 1' textbooks. The most higher level of cognitive demands about the concepts have been discussed here due to the focus of the concepts. The first, the cognitive demand level about 'three states of substances' depending on the motion of their particles in 6 textbooks is a early formal operational stage because of using by the application of kinetic theory. The second, the cognitive demand level about 'diffusion' and 'evaporation' is a early formal operational stage, because the particles move around faster so they can change their position. The third, the cognitive level of the pressure and volume in a gas is a early formal operational stage because of explaining only phenomena in simple correspondence with formal model of kinetic theory. And simple functional relationships beyond linear on the graph of the volume and pressure of gas, the volume and temperature of gas is also a early formal operational stage. The fourth, the cognitive level of the energy of heat by a change of the state is also a early formal operational stage because kinetic theory picture accepted as providing explanation by the change of the state. And functional relationships beyond linear on the graph of the explanation of boiling point of water in water is also a early formal operational stage.

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.128-136
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• 2012

The purposes of this study were to evaluate the level of PCK which middle school science teachers have on the concept of density and to analyze the characteristics of science teachers' content representation on the concept of density by their PCK level. For that purpose, 20 science teachers were selected and asked to answer the questionnaire on the eight aspects of CoRe. Results of this study indicated that the science teachers' PCK levels were low in general and evaluated as below average. The differences among the characteristics of science teachers' content representation by their PCK level were high in seven aspects of CoRe but the one aspect of the understanding of learner's preconception. These differences were analyzed and the patterns shown by the science teachers in eight aspects of CoRe were drawn in this study. It was also found that the characteristics drawn in eight aspects of content representation shown by the teachers whose PCK level was medium were close to those whose PCK level was low rather than high in most aspects of CoRe.