• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.3
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• pp.343-348
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• 1986

An optical interference method was developed for measuring rapidly growing and evaporating liquid condensate films (e.g., Na$_{2}$SO$_{4}$, $K_{2}$SO$_{4}$) on solid surface exposed to flowing combustion product gases at film thicknesses well below the onset of complications due to run-off. To develop this optical system, this study investigated the optical parameters (e.g., polarization state, incident angle, target roughness, etc.) Trends for the Na$_{2}$SO$_{4}$(l) and $K_{2}$SO$_{4}$(l) deposition rates as a function of target temperature using this optical measuring system agree with the theoretical prediction of the vapor deposition. This study was able to extend the experimental range for vapor plus condensed phase transport and deposition. While previously unable to measure the evaporation rates interferometrically, these rates are estimated from the results of the investigation of polarization states.

• Journal of The Korean Association For Science Education
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• v.24 no.5
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• pp.1008-1017
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• 2004

In physics education, language is an fundamental learning tool as in other subjects. In writing activity, students can get fair opportunities to express their own ideas during the class. Even though there are various styles of writing, students are usually supposed to make a report in their science classes. But there have been few studies in science education on the tasks and features of student's science writing. In this research, different styles of writing tasks were designed for science classes, and students' writing was analysed in terms of conceptual and emotional aspects. Also the usefulness of each task type was discussed relating to school physics education. Four types of writing, i.e. , , , and writing were developed, and 'The reflection of light' was selected as the theme and given to students. Four types of writing were analysed in this paper. In each type of writing, students showed different features in their conception. They also showed emotional expressions in imaginative writing types, that is, and types. Based on these results, it is recommended that in physics teaching various types of writing need to be designed, developed and applied according to the aim of a particular lesson.

• Journal of The Korean Association For Science Education
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• v.33 no.2
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• pp.229-248
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• 2013

The purpose of this study is to develop sequential concept tests (ConcepTest) for teachers' conceptual change on the straight propagation of light through in-service training of science teachers by peer instruction. We revised the ConcepTests for attaining the goal concept by implementing similar training courses for teachers three times and analyzing the results using both Hake gain and verbal protocol. The final form helped most teachers to reach the goal concept. While teachers are solving a given concept problem test, they had shown not only significant cognitive conflict to select one among candidate answers, but also used the concept obtained through the previous problem. The sequential ConcepTests developed in this study can be useful for training elementary and secondary teachers or pre-service teacher education.

• Journal of The Korean Association For Science Education
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• v.29 no.6
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• pp.712-729
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• 2009

This study aims to research high school students' misconception of botanic photosynthesis and respiration, and as the measure of rectifying the misconception, to develop the teaching program based on Driver's conceptual change model, applying it to classes and observing the effect. Selected as the research subject was sixty-six students in 1st year of a highschool located in Busan who had chosen Biology Learning as discretionary subject, with their conceptual level on botanic photosynthesis and respiration researched through tests in drawing and descriptive writing. As a consequence of applying drawing as a way of classifying the levels of students' misconception on photosynthesis and respiration, many students' drawings included their misconception caused by textbooks or scientists, but after application of Driver's conceptual change model, they drew scientific drawings including the fundamental factors of botanic photosynthesis and respiration such as light, carbon dioxide, water, glucose, oxygen, leaf, chloroplast, mitochondria, stoma, and energy. Likewise, as a result of the descriptive writing test implemented for researching the students' conception on the various aspects of botanic photosynthesis and respiration, many students in the pretest showed misconception on the point of time and location at which botanic photosynthesis and respiration occur, botanic nutrient, the role of a leaf in photosynthesis, and the relation between botanic photosynthesis and respiration, but after teaching based on Driver's conceptual change model, their misconceptions on photosynthesis and respiration were rectified to a high degree.

• Journal of The Korean Association For Science Education
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• v.22 no.2
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• pp.276-285
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• 2002

In this study the concepts for science learning of physics and earth science presented in the seventh grade science textbooks for the seventh national curriculum of Korea approved by the ministry of education were analyzed in terms of the concrete and formal concept level. The parts of textbook analyzed for science learning consist of three sections in physics such as light, force, and waves, and three sections in earth science such as the structure of the earth, the substance of crust, and the movement and composition of the ocean. The analyzed results showed that the number of scientific concepts were differed from 54 to 74 in physics and from 86 to 120 in earth science depending upon publishers. In general, the concepts for science learning in the physics were found to be more in the formal level than the concrete level. However, the concepts for science learning in earth science were found to be more in the concrete level than the formal level. The analyzed results suggest that the concepts of science learning should be considered the learner's cognitive level and the sections should be disposed depending on the degree of difficulty for writing the science textbook. Therefore, it seems to be important to review carefully whether the textbook meets the object of the seventh curriculum of Korea during the process of the investigation for the science textbook.

• Journal of the Korea Convergence Society
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• v.11 no.7
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• pp.137-144
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• 2020

Based on the basic concepts and roles of the Science Museum, the research and development of the "Sound Light" interaction exhibition contents and experience exhibition space aimed at providing the exhibition, education and experience of scientific principle directly related to daily life will be implemented in the "Sound Light" exhibition space of the Gwangju National Science Museum. The scope of the research is to define the conditions and elements of the museum's hands-on exhibition by examining the case and status of the existing science museum's experience-type content prior research, and research and development of experience-type exhibition scenarios and contents for children based on them. The results of this research and development content are firstly developed with the theme of light and sound as interactive hologram experience content. Second, by multi-faceted media facade through projection mapping by multiple projectors, visual wide and spectacular screen composition and animation are realized. Third, visitors-oriented exhibitions and experiences that can interact with visitors by moving various colors and sounds together. Finally, interactive content is provided through hologram interfaces through hologram screens to encourage active participation of many visitors in viewing rather than simply delivering exhibition information and to promote revisiting the exhibition. Through a series of studies, it was possible to research and develop contents and experience exhibition spaces with theme park characteristics, which are the trend of science museums.

• Prospectives of Industrial Chemistry
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• v.24 no.6
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• pp.19-31
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• 2021

자극응답성 액정 엘라스토머(liquid crystal elastomer)는 하이드로겔(hydrogel), 형상 기억 고분자(shape memory polymer)와 더불어 생체 특성을 모방한 인공 근육, 소프트 액추에이터 및 소프트 로봇을 위한 스마트 소재로 최근 높은 관심을 받고 있다. 특히, 액정 엘라스토머는 고무 탄성과 액정 이방성이 결합된 비등방성 탄성 고분자로, 열, 빛, 전기 및 수분과 같은 외부자극에 반응하여 가역적이며, 액정 분자들의 배향조절을 통한 프로그램된 변형이 가능하다. 액정 엘라스토머가 개념 증명을 하는 수준을 넘어 실제로 유용한 소프트 액추에이터 및 로봇 시스템에 적용되기 위해서는 우수한 구동력 및 작업 용량, 높은 구동 변형률, 빠른 응답 시간, 낮은 구동 온도, 다양한 외부 자극반응성 및 높은 에너지 전환 효율 등을 확보하는 것이 중요하다. 본 기고문에서는 액정 엘라스토머의 개념에 대해 소개하고, 이러한 소재가 소프트 액추에이터로써 광범위하게 활용될 수 있도록 다양한 성능들을 향상시킬 수 있는 방법에 대해 소개하고자 한다.

• Journal of Science Education
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• v.36 no.1
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• pp.84-93
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• 2012

We have studied possibilities of Peer Instruction(PI) to train in-service science teachers in elementary and middle schools through both degree of conceptual changes and investigating responses to questionaries. 169 teachers were attended and the subject for training was about light propagation to teach scientific conception about a pin hole camera. 6 conceptests were developed. Degree of conceptual changes was analyzed from results obtained from 24 elementary and 32 middle school teachers among them. On the other hand, answers to questionaries were obtained from 135. Relatively high gain near to about 0.7 in conceptual changes was obtained even though their initial levels were quite low. Interesting point is that elementary teachers have higher initial level and larger gain than middle school teachers. Teachers have very much enjoyed and showed strong support to PI for helping conceptual change, and willing to use PI to their own class. Also they conceived dealing concept in teacher training is very important and evaluated PI very positively for teacher training.

• Korean Journal of Child Education & Care
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• v.18 no.4
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• pp.65-89
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• 2018

Objective: The purpose of this study is to analyze the science concepts and teaching and learning methods presented in the science education-related activities of the Nuri Curriculum teacher guidebooks for ages 3-5. Methods: The research data included 772 activities related to science education in the teachers' guidebook. The analysis of science concepts was based on physical science (force and motion, physical structure, electricity and magnetism, light and shadow, sound properties), chemistry (material properties, material reaction), life science (organizational structure, growth and change, heredity and evolution, animal plant and human relationships), earth science (earth system interaction, earth system structure, and universe), engineering (designed world, engineering design, engineering, technology and society) and ecology (environment preservation). Teaching and learning methods were analyzed according to the types of small and large group activities and of free play activities. Results: Science concepts were mainly presented in the fields of engineering, chemistry, and life science commonly among children aged 3-5, whereas the concepts of physical science were lowly presented in all ages. Science concepts appeared mainly in the daily subjects of 'animal plant and nature', 'life tools', 'environment and life', and 'spring, summer, autumn and winter'. As the teaching and learning method, free paly activities (science area, free outdoor selection activity, math and manipulative activity) were mostly used for the ages of 3 and 4, and small and large group activities (cooking, story sharing, music activity) were for the age of 5. Conclusion/Implications: It is necessary to select the level of science area and concept that can be taught according to the age of children and the timing of the teaching.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10b
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• pp.533-535
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• 1999

자궁경부진 세포인식 시스템에 있어서 가장 중요한 것이 영상처리를 이용하여 세포핵과 세포질을 추출하여 세포의 형태적인 정보를 알아내는 과정이다. 기존의 전역 thresholding 기법이나 region growing의 경우는 pap smear 검사를 통해 얻어진 세포 영상을 분할할 수 있는 region growing 기법을 제안한다. 제안된 region growing 기법은 초기에 seed를 검출할 때 local threshold growing 기법을 제안한다. 제안된 region growing 기법은 초기에 seed를 검출할 때 local threshold 개념을 도입하여 seed의 검출을 고르게 하고, 2가지 확장 조건을 사용하여 영역을 확장한다. 첫 번째 확장 조건은 비정상 세포나 artifact가 많아서 어둡게 나타나는 영상이나 세포질과 배경의 경계가 뚜렷하지 않아서 세포질의 구별이 어려운 영상의 영역 분할이 가능하도록 그 특성을 반영하고, 두 번째 조건은 세포가 흡수하는 빛의 양이 일정하다는 가정으로 영상에서의 지역 특성(gray level, color 등을 반영한다. 제안된 기법은 정상세포 영상뿐만 아니라 비정상 세포 영상에 대하여 over-segment나 under-segment하는 경우를 줄여서 영역 분할에 좋은 결과를 보인다.