• Journal of agriculture & life science
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• v.45 no.2
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• pp.43-50
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• 2011

Hibiscus cannabinus L. is a plant in the Malvaceae family, that was seeded at June 1st in 2010 and harvested at November 18th. The present study was designated to investigate the safety for host cells, antibacterial effects of Hibiscus cannabinus L. of flower (HCME-F) or leaf (HMEF-L) methanol extract for typical Gram's positive bacteria (St. aureus and Str. epidermidis) or Gram's negative bacteria (S. typhimurium and E. coli). In treatment of different concentrations of HCME-F or HMEF-L (1, 50 and $100{\mu}g/ml$), cytotoxic effects were not shown to RAW 264.7 cells until 24 h incubation. In determination of antibacterial activity of HCME-F or HMEF-L, the antibacterial activities for St. aureus and Str. epidermidis were markedly increased compared to that of untreated control group, but antibacterial activity of HCME-F or HMEF-L for S. typhimurium and E. coli were not changed. Taken together, we demonstrated that methanol extract of HCME-F or HMEF-L showed the safety for RAW 264.7 cells and antibacterial activities for Gram's positive pathogenic bacteria St. aureus and Str. epidermidis. These findings suggest that a methanol extract of Kenaf flower or leaf may be useful alternatives of conventional chemotherapies for dermatitis and mastitis causing Gram's positive pathogens such as Stapylococcus spp. and Streptococcus spp. in domestic animals and humans.

• Journal of Korean Elementary Science Education
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• v.42 no.3
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• pp.467-479
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• 2023

For the successful implementation of education using artificial intelligence (AI) in schools, the perception of teachers is important. This study focuses on elementary school teachers and their perception of the need and teaching efficacy of science classes using AI before and after participating in a research school program. The analysis explores four key aspects, namely, learning, teaching, assessment, and communication. The study recruited 24 elementary school teachers from a school designated by the Gangwon Provincial Office of Education to participate in a year-long research school program. The study collected data using pre- and post-program surveys to explore changes in the perception of teachers regarding AI-based science classes. Furthermore, the researchers conducted individual in-depth interviews with four elementary school teachers to investigate the experience factors that influenced the changes in their perception of the aforementioned classes. The main findings were as follows. First, elementary school teachers were positively aware of the need for science classes using AI even prior to their research school experience; this perception remained positive after the research school program. Second, the science teaching efficacy of the elementary school teachers using AI was generally moderate. Even after the research school experience, the study found no statistically significant increase in efficacy in teaching science using AI. Third, by analyzing the necessity-efficacy as quadrants, the study observed that approximately half of the teachers who participated in the research school reported positive changes in learning, teaching, and assessment. Fourth, the study extracted four important experience factors that influenced the perception of the teachers of science classes using AI, namely, personal background and characteristics, personal class practice experience, teacher community activities, and administration and work of school. Furthermore, the study discussed the implications of these results in terms of the operation of research schools and science education using AI in elementary schools.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.4
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• pp.357-368
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• 2008

On July 31, 2008, the Government issued the construction and operation permit for the first low and intermediate level radioactive waste disposal facility in the Republic of Korea. In this paper, the fundamental regulatory framework, regulatory requirements and technical standards of the disposal facility are introduced, and the phased review process adopted for evaluation of the safety of the facility is briefly described. The Atomic Energy Act sets forth a stepwise regulatory framework for the whole life-cycle of the disposal facility such as siting, design, construction, operation, closure and institutional control. More detailed regulatory requirements and technical standards are stipulated in the subsequent regulations of the Atomic Energy Act and a series of Notices issued by the Ministry of Eduction, Science and Technology. The Korea Institute of Nuclear Safety, as entrusted by the Ministry under the Atomic Energy Act, conducted safety review on the disposal facility, and evaluated the compliance with relevant criteria in all technical elements(i.e. siting and structural safety, radiological environmental impact, operational safety, systems and components, quality assurance, and total systematic performance assessment, etc.). The overall safety review process can be phased into inception phase, initial review phase, main review phase and completion phase. The review results were reported to and deliberated by the five Sub-committees of the Special Committee on Nuclear Safety, and then reported to the Ministry. The Ministry issued the construction and operation permit of the disposal facility through the deliberation of the review results by the Nuclear Safety Commission. Hereafter, the safety of the repository will be reassured by a series of subsequent regulatory inspections and reviews under the Atomic Energy Act. In addition, the licensee's continuous implementation of the "Safety Promotion Plan" may also enhance the long-term safety of the repository and contribute to build-up the confidence of the safety case.

• Journal of the Korean Geotechnical Society
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• v.37 no.3
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• pp.19-30
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• 2021

The presence of the hydrate-bearing sediments in Ulleung Basin of South Korea has been confirmed from previous studies. Researches on gas production methods from the hydrate-bearing sediments have been conducted worldwide. As production mechanism is a complex phenomenon in which thermal, hydraulic, and mechanical phenomena occur simultaneously, it is difficult to accurately conduct the productivity and stability analysis of hydrate bearing sediments through lab-scale experiments. Thus, the importance of numerical analysis in evaluating gas productivity and stability of hydrate-bearing sediments has been emphasized. In this study, the numerical parametric analysis was conducted to investigate the effects of the bottom hole pressure and the depressurization rate on the gas productivity and stability of hydrate-bearing sediments during the depressurization method. The numerical analysis results confirmed that as the bottom hole pressure decreases, the productivity increases and the stability of sediments deteriorates. Meanwhile, it was shown that the depressurization rate did not largely affect the productivity and stability of the hydrate-bearing sediments. In addition, sensitivity analysis for gas productivity and stability of the sediments were conducted according to the depressurization rate in order to establish a production strategy that prevents sand production during gas production. As a result of the analysis, it was confirmed that controlling the depressurization rate from a low value to a high value is effective in securing the stability. Moreover, during gas production, the subsidence of sediments occurred near the production well, and ground heave occurred at the bottom of the production well due to the pressure gradient. From these results, it was concluded that both the productivity and stability analyses should be conducted in order to determine the bottom hole pressure when producing gas using the depressurization method. Additionally, the stress analysis of the production well, which is induced by the vertical displacements of sediments, should be evaluated.

• Journal of The Korean Association For Science Education
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• v.21 no.3
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• pp.473-486
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• 2001

The study aimed to evaluate an activity-oriented extracurricular science program as informal science education through the assessment of opinions of student participants and lead-students and lead-teachers who organized the program. An 'Exciting Science Fair' was designed by science teachers and students and provided for 857 students for two days in early 1998. Students chose a course of science activities designed by different levels of student knowledge and interests. During their own science activity courses, the participating students were grouped as pair of two students and guided and facilitated by lead-students. A survey instrument was developed by researchers and asked respondents' opinions of 121 participating students, 72 lead-students, and 19 lead-teachers to the significance of program goals, degree of goal achievement, and program planning and management system before and after the program. It was found that most student participants, lead-students and lead-teachers satisfied with the efficiency of the program. However, it was recommended that the program should place more emphases on engaging student participants in science activities, strengthening scientific inquiry through activities, and increasing science content related to student daily life. It was also suggested that advertizement of the program be publicized in advance through media, an effect teaching-learning strategy for lead-students be developed, and collaboration among lead-students and lead-teachers be improved.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.716-730
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• 2016

The meaning and role of science culture based on such values as rational thinking, creativity, critical validation has been growing in the process of discussing various social problems. In order to diffuse science culture, it is important to sustain citizen's activeness by providing contents which can induce interest on the base of two-way communication between public and experts and to support citizen activities performed voluntarily. To that end, various people such as scientist, government policymaker, communicator, those in charge of culture and art, exhibition curator should make up collaboration system and such requirement as motivation, leadership, agreement between the participants, communication, trust relationship is also to be met properly in order to proceed collaboration efficiently. This study reviews how these factors are coming true in governmental project for science culture and develops proposal for improvement on the base of opinions collected through expert meetings, interviews, workshop and data research. In addition, it explains that government must strengthen scientific cultural project personnel and lay infra such as communications hub, regional center, platform and improve the business selection method to promote competition and collaboration among project participants with reformation of reward and regulatory systems. It is performed to suggest comprehensive ways to increase efficiency of project for science culture out of not the deficit model which regard public as passive acceptant but context model or PES(public engagement in science) that take public who focus his attention and participate actively into account.

• Journal of Korea Technology Innovation Society
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• v.20 no.1
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• pp.153-174
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• 2017

This study tried to suggest South-North Korea's S&T cooperative strategies and priority areas using mixed-methodology. First, survey research was conducted to analyze the understanding of scientists how they think about these issues. We surveyed scientists whose names are on the KOFST mailing list and analyzed 485 questionnaire responses. After that, experts who are participating in FGI discussed more deeply about the survey results and suggested the feasible strategies and projects. The results suggest some findings about priority cooperation area, new projects and strategies. Priority areas of S&T cooperation are following; agriculture, electricity & energy, and health care. However, more important thing than these priority areas is how to approach the inter-Korean S&T cooperation. More strategic approach is needed while promoting exchange and cooperation projects with north-korea. Also more long-term approach is needed to maintain the sustainability of this S&T cooperation.

• Journal of the Korean earth science society
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• v.31 no.4
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• pp.378-391
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• 2010

The purpose of this study was to investigate the graph interpretation ability and perception of high school students and preservice secondary teachers in Earth science. We developed two different instruments; one was a graph interpretation ability inventory that consists of 9 graph types with 18 items, and the other one is two questionnaires to explore the participants' perception about Earth science-related graph. The results of this study are as follows: High school students and preservice secondary teachers demonstrated their remarkable ability in interpreting a line graph, but showed their limited ability with the graph of overlapped and directional change, which means the graph interpretation ability was affected by a graph type; two groups participated in this study revealed a considerable difference in the graph interpretation ability depending on the grade level; preservice teachers were superior to high school students in discriminating two graphs, the representation method, which are different with the same topic; and many participants in both groups considered that the property of Earth science graph was considerably different from that of other science subjects, especially in directional change graph, scatter graph, contour map, and domain graph. The results suggest that the effective graph instruction strategies be developed in Earth science learning.

• Journal of The Korean Association For Science Education
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• v.40 no.4
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• pp.359-374
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• 2020

This study is a complex type consisting of survey study and self-study. The former investigated elementary teachers' epistemological beliefs on convergence knowledge and teaching. As a representative of the result of survey study I, as a teacher as well as a researcher, was the participant of the self-study, which investigated my epistemological belief on convergence knowledge and teaching and my execution of convergent science teaching based on family resemblance of mathematics, science, and physical education. A set of open-ended written questionnaires was administered to 28 elementary teachers. Participating teachers considered convergent teaching as discipline-using or multi-disciplinary teaching. They also have epistemological beliefs in which they conceived convergence knowledge as aggregation of diverse disciplinary knowledge and students could get it through their own problem solving processes. As a teacher and researcher I have similar epistemological belief as the other teachers. During the self-study, I tried to apply convergence knowledge system based on the family resemblance analysis among math, science, and PE to my teaching. Inter-disciplinary approach to convergence teaching was not easy for me to conduct. Mathematical units, ratio and rate were linked to science concept of velocity so that it was effective to converge two disciplines. Moreover PE offered specific context where the concepts of math and science were connected convergently so that PE facilitated inter-disciplinary convergent teaching. The gaps between my epistemological belief and inter-disciplinary convergence knowledge based on family resemblance and the cases of how to bridge the gap by my experience were discussed.

• Journal of The Korean Association For Science Education
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• v.35 no.4
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• pp.691-707
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• 2015

This study aims to develop biology teachers' education program based on argumentation activity about core concepts of evolution and to analyze the characteristics of core concepts of evolution learned during the program. The eight core concepts of evolution in this study were variation, heritability of variation, competition, natural selection, adaptation, differential reproductive rate of individuals, changes in genetic pool within a population, and macroevolution. The performances of teachers participating in the program were compared before and after argumentation activities; consisting of seven sessions on the eight core concepts of evolution. The process of the program was specially designed by learning cycle model for teacher education, consisting of seven phases: identification of the task, production of a tentative argument, small group's written argument, share arguments with the other groups, reflective discussion, final written argument, and organization by an instructor. Participants in the study were two pre-service biology teachers and four in-service biology teachers. The results suggest that biology teachers reduced the teleological explanation for biological evolution and improve its adequacy after the intervention. Teachers lacked the opportunity to discuss variation, heritability of variation, competition, and macroevolution because science textbooks lack information on the concepts of biological evolution. The results of this study suggest that because the argumentation program developed for teachers helps to improve understanding the concepts of evolution and to reduce inadequate conceptions in biology, teacher education programs using argumentation activity and eight core concepts of evolution will play a role for efficient evolution education for biology teachers.