• Journal of the Korean School Mathematics Society
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• v.11 no.3
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• pp.399-420
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• 2008

In this paper we solve various triangle construction problems related with radius of escribed circle using algebraic method. We describe essentials and meaning of algebraic method solving construction problems. And we search relation between triangle construction problems, draw out 3 base problems, and make hierarchy of solved triangle construction problems. These construction problems will be used for creative mathematical investigation in gifted education.

• Journal of Life Science
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• v.29 no.6
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• pp.724-734
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• 2019

The present study investigated the cytotoxicity of particulate matter (PM) derived from car air filter (outdoor PM) and home cleaner filter (indoor PM) in the various human cell lines. Each outdoor and indoor PM were harvested by ethanol extraction method, subsequently sieved with 10 um filter paper, sterilized with autoclave and added to culture media. The half maximal inhibitory concentration ($IC_{50}$) values was significantly (p<0.05) lower in the outdoor PM, compared with indoor PM, and the significantly (p<0.05) higher $IC_{50}$ values were observed in the cancer cell lines (A-549 lung adenocarcinoma and AGS stomach adenocarcinoma), than those of normal MRC-5 fibroblasts and dental papilla tissue derived-mesenchymal stem cells (DSC). After being exposed to $100{\mu}g/ml$ outdoor PM for 7 days, the population doubling time (PDT) was significantly (p<0.05) increased in especially MRC-5 and DSC cell lines, compared with untreated cell lines. Further, the expression of senescence-associated ${\beta}$-galactosidase activity was up-regulated in all the cells exposed to outdoor PM than those of untreated control. Besides, the expression level of inflammation-associated genes, such as cyclooxygenase-2 (COX-2) and interleukin-6 (IL-6) was found to be significantly (p<0.05) increased in the outdoor PM-treated cell lines than those of untreated cell lines. Our results showed that PM induces the cytotoxicity via arrest of cell growth, cell damage and inflammation response.

• Korean Journal of Materials Research
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• v.29 no.8
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• pp.491-496
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• 2019

In this study, we prepare pure $WO_3$ inverse opal(IO) film with a thickness of approximately $3{\mu}m$ by electrodeposition, and an ultra-thin $TiO_2$ layer having a thickness of 2 nm is deposited on $WO_3$ IO film by atomic layer deposition. Both sets of photoelectrochemical properties are evaluated after developing dye-sensitized solar cells(DSSCs). In addition, morphological, crystalline and optical properties of the developed films are evaluated through field-emission scanning electron microscopy(FE-SEM), High-resolution transmission electron microscopy(HR-TEM), X-ray diffraction(XRD) and UV/visible/infrared spectrophotometry. In particular, pure $WO_3$ IO based DSSCs show low $V_{OC}$, $J_{SC}$ and fill factor of 0.25 V, $0.89mA/cm^2$ and 18.9 %, achieving an efficiency of 0.04 %, whereas the $TiO_2/WO_3$ IO based DSSCs exhibit $V_{OC}$, $J_{SC}$ and fill factor of 0.57 V, $1.18mA/cm^2$ and 50.1 %, revealing an overall conversion efficiency of 0.34 %, probably attributable to the high dye adsorption and suppressed charge recombination reaction.

• Journal of Science Education
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• v.35 no.2
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• pp.149-158
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• 2011

The purpose of this study is to improve education program for Informal Science Education Institution by analyzing education program of Natural History Museum, one of informal science education institution. This research subject is Seodaemun Museum of Natural History, located in Seodaemun-Gu, Seoul. It is Public Natural History Museum, which runs more than 60 education programs every year continuously for recent 6 years. Objects of this study are 32 education programs for 3rd to 6th grade of elementary school. The result of study shows that teaching materials of programs, run by informal science education institution, don't contain enough script and activity for improving creativity and inquiring mind. As the result of the study, it is required that guidance plan of education program be developed with more activities, teaching method and script, to seek quality of class than quantity of that when developing education program of science education institutes. And it is required to develop teaching material using creative technique and to improve medium and long term program for development of feedback.

• Journal of The Korean Association For Science Education
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• v.32 no.4
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• pp.717-728
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• 2012

The purpose of this study is to analyze the argumentation of gifted students in the perspective of rebuttal. Rebuttal is a significant indicator of argumentation quality; it is also an essential component for science learning through interaction. However, most previous research point out insufficient use of rebuttal in student's argumentation. The argumentation of 37 8th grade students, enrolled in institutes for the scientifically gifted in Seoul, are observed and recorded for 4 hours. The argumentation topic is about how to measure the brightness of the sun. Based on Verheij's (2005) five types of rebuttal patterns, the features of rebuttal are analyzed. It is found that students' argumentation include all of the five rebuttal types: rebuttal of the data, the claim, the warrant, warrant's applicability, and connection between data and claim. It is also found that these five types can be categorized in two groups. The first group consists of first three types and is characterized by the disagreement with the validity of what has been said. The second group consists of the last two types and is characterized by the suggestion or additional information for missing links in argumentation.

• Journal of Educational Research in Mathematics
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• v.24 no.3
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• pp.333-357
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• 2014

This study resulted from a study regarding creative STEAM System based upon an experiment with the center of gravity. The results of the study are constructed by a fusion of mathematics and physics, showing that they are the same as mathematical calculations. Also, students can find that center of gravity of an object is in equilibrium on a metal rod when the center of gravity exactly is placed on the rod. The fact that an experimental results are correspond to calculations can maximize the effectiveness of teaching. And also this study has the following effectiveness. First, the exact construction and calculations arouses good competition among students. Second, this experiment can give students a motivation for study and increase their thinking in classes because the theoretical background of center of gravity experiment is basically attributed to math and science classes in school. This study includes three different types of center-of-gravity experiments. One is a simple type of experiment in which center of gravity exists inside of an object. Another is a complicated one in which the center of gravity is also inside of an object. However, the third type is an experiment in where the center of gravity is outside of an object. Therefore, it gives students an opportunity to discuss how to confirm equilibrium on a metal rod when the object has its center of gravity outside. Having discussions in class will allow students to have a critical way of thinking. In addition, searching for a way to solve a problem will increase creativity of students as well. And the last type is finding the center of gravity of a big acrylic panel where multiple objects are on the panel. According to the survey and interview conducted by students who participated in this program, teaching based on creative STEAM system helps students to get a better understanding and more fast acquisition of knowledge. We can expect that a well-planned creative STEAM system through a continuous study will be both effective and efficient in educating critical and creative students.

• Journal of Science Education
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• v.33 no.1
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• pp.12-30
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• 2009

The purpose of this study was to analyze recognition characteristics of science gifted students on the earth system based on their thinking style. The subjects were 24 science gifted students at the Science Institute for Gifted Students of a university located in metropolitan city in Korea. The students' thinking styles were firstly examined on the basis of the Sternberg's theory of mental self-government. And then, the students were divided into two groups: Type I group(legislative, judicial, global, liberal) and Type II group(executive, local, conservative) based on Sternberg's theory. Data was collected from three different type of questionnaires(A, B, C types), interview, word association method, drawing analyses, concept map, hidden dimension inventory, and in-depth interviews. The findings of analysis indicated that their thinking styles were characterized by 'Legislative', 'Executive', 'Anarchic', 'Global', 'External', 'Liberal' styles. Their preference were conducting new projects and using creative problem solving processes. The results of students' recognition characteristics on earth system were as follows: First, though the two groups' quantitative value on 'System Understanding' was very similar, there were considerable distinctions in details. Second, 'Understanding the Relationship in the System' was closely connected to thinking styles. Type I group was more advantageous with multiple, dynamic, and recursive approach. Third, in the relation to 'System Generalization' both of the groups had similar simple interpretational ability of the system, but Type I group was better on generalization when 'hidden dimension inventory' factor was added. On the system prediction factor, however, students' ability was weak regardless of the type. Consequently, more specific development strategies on various objects are needed for the development and application of the system learning program. Furthermore, it is expected that this study could be practically and effectively used on various fields related to system recognition.

• Journal of the Korean earth science society
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• v.33 no.7
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• pp.672-682
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• 2012

The purpose of this study is to investigate elementary school science gifted students' perceptions about Earth systems and environmental problems. A total of 28 students in the attached center for science gifted education to the university participated in this study. Through the survey, participating students were asked to respond to their self-reported knowledge level, the perceived danger levels, certainty, and tangibility of the selected 13 Earth environmental problems. The DAET (Draw-An-Earth Test)-Checklist were developed and used to analyze the images of the Earth drawn by students. Additional interviews were conducted to clarify the meanings and components of students' image. Results indicated that a total of 80 components regarding Earth systems, 11 components of Earth systems interaction, and 4 components related to Earth systems literacy were identified through the DAET-Checklist and additional interviews. Regarding the students' self-reported knowledge level, they reported that they were most knowledgeable about air pollution, global warming, and water pollution. and they also recognized global warming, air pollution, and water pollution as the most dangerous problem. Results indicated that participants were certain that acid rain, air pollution, and water pollution were problematic, and that acid rain, air pollution, and forest desertification were tangible issues. It is anticipated that this study contributes to understanding the elementary school science gifted students' perceptions toward the selected Earth systems and environmental problems.

• The Journal of the Korea Contents Association
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• v.12 no.8
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• pp.343-354
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• 2012

The purpose of this research was to compare the concentration variation between the sport talented children who have been applied with a sport program and the ordinary children who did not. The experiment group was composed of 59(male:32, female:27) sport talented children who were selected from the center of Busan University sport talent in April 2010. The control group was made up of 148 students who participated in 3 elementary schools located in Busan. Among these ordinary students 80 participants were finally used, as some of the students were excluded who were playing as athlete or studying in Science gifted program, FAIR concentration test sheet was used for this study, which was reformed for Korean version by Oh(2002). Covariance analysis was applied for using SAS 9.1 package, and the following conclusions were drawn. First, both the sport talented group and ordinary group of FAIR concentration's 3 subfactors were improved significantly after 8 months. Second, no difference between the sport talent group and ordinary group were found in the variations of post test of concentration's 3 subfactors. Especially there was no difference among groups in oneway-ANOVA using data of post test.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.11a
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• pp.1502-1504
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• 2011

최근 소셜 네트워크를 이용한 학습 방법이 활발하게 연구되고 있다. 동일한 영역에 지식을 공유하고 새로운 정보를 웹에서 생성하는 등 집단지성 학습자들이 계속적으로 늘어가고 있으며, 특히 IT 학습을 위한 온라인기반 교육은 관심도와 직군에 따른 집단지성을 통한 효과적인 학습 성취도를 높일 수 있다. 따라서 본 연구는 웹 기반을 중심으로 한 IT집단지성 학습자들의 개인차를 파악하고, 각 특성에 따른 다양성을 적용하여 학습과정 중 자신에게 적합한 학습경로를 파악하여 학습의 지속적인 진행에 있어 정확한 자료를 제공하고 효율적인 학습의 진행이 이루어져 성취도를 높일 수 있도록 학습 성취도 예측 시스템을 연구 개발하는 데 그 목적이 있다. 이를 위해 먼저 IT습자들이 자신의 개인차를 파악하기 위해 학습의 유형, 학습몰입, 인지적 능력, 개인적 성향, 창의적 성향 등을 활용한 검사도구의 개발이 선행되어야 한다. 다음으로, IT 전공자 혹은 비전공자를 대상으로 예비조사를 실시하고 그 결과를 바탕으로 학습 성취도 예측을 가능하게 하기위한 시스템을 설계하고자 한다. 향후 본 연구의 결과로 학습자의 학습 성취도를 향상시키고, 예측 결과에 의한 집단지성 그룹을 좀 더 효과적으로 운영 할 수 있는 시스템을 구축할 수 있을 것으로 기대한다.