• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2001.10a
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• pp.267-269
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• 2001

• Journal of Information Display
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• v.3 no.4
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• pp.1-3
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• 2002

The antiferroelectric liquid crystal display (AFLCD) is a unique display that can at demonstrate a moving image perfectly the passive matrix driving scheme. We optimised driving the waveform and introduced a dual-driving method. Also, by improving this driving method and using line inversion method, we realize the AFLC display of high image quality with $160(RGB){\times}240$, 32768 colors, crosstalk free and flicker free contrast ratio is greater than 60:1, and the brightness is above 200 $cd/m^2$.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.545-547
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• 2002

The antiferroelectric liquid crystal display (AFLCD) is unique display that can show the perfect moving image using the passive matrix driving scheme. We optimized the driving waveform and introduced the dual driving method. Also, by improving this driving method and using line inversion method, we realized AFLC display with high image quality, which has 160(RGB)${\times}$240, 32768colors, crosstalk free and flicker free. The contrast ratio is greater than 60:1, and the brightness is above 200cd/$m^2$.

• Bulletin of the Korean Chemical Society
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• v.15 no.7
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• pp.531-533
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• 1994

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.05a
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• pp.166-166
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• 2003

In terms of the risk assessment, qualitative and quantitative informations are needed to estimate the exposures of environmental pollutants, which may be potentiality of risks, and those are the information about the changes caused by the chemical transportation among environmental media and transformation in environmental media by duration. The various fate mechanism of chemical is possible for estimation of chemical concentration in environmental media. Since there are limitations in measuring the change of chemical concentration within all medium according to the time period, estimating method through modeling are developed.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.197-197
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• 2002

In terms of the risk assessment, qualitative and quantitative informations are needed to estimate the exposures of environmental pollutants, which may create risks, and those are the information according to the changes caused by the movement of substances from the pollutant and duration.(omitted)

• Journal of Korean Elementary Science Education
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• v.28 no.4
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• pp.390-403
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• 2009

We have examined the perception of teachers and students in elementary schools toward the frontier science and analyzed corresponding contents in science textbooks in Korea and the U. S. in order to promote a good guidance for the frontier science education. We prepared separate questionnaires for teachers and children, respectively, and analyzed the responses obtained from 244 teachers and 1,000 students in five elementary schools. For the analysis of how to introduce the frontier science, we investigated textbooks such as Science, Society and Practical Arts of Korean elementary school, and an American science textbook published by Scott Foresman. This study revealed that teachers are well aware of the importance of the frontier science, however, they are inactive in conducting the subject in class rooms because of their insufficient scientific knowledge and poor environment for teaching. It has been found that children had strong interest in the frontier science, however, opportunities to learn the topic are not properly provided. The frontier science m the American science textbook turned out to be more systematically introduced than that in Korean ones.

• Journal of Engineering Education Research
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• v.20 no.1
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• pp.3-9
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• 2017

This study examined 39 elementary teachers' perceptions on the frontier science teaching and their teaching efficacy. The results showed: elementary teachers were interested in and were well aware of the importance of the frontier science in human life and in this society. They also agreed with the necessity of teaching frontier science in elementary school. They, however, had perceptions that frontier science may not be appropriate for the level of elementary students. Moreover, the poor educational environment may act as constraints for frontier science teaching. The change of elementary teachers' teaching efficacy(t=-13.67, p<.01) was statistically significant after their participation of developing STEAM program on frontier science and practicing its lessons.

• Journal of Drive and Control
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• v.9 no.1
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• pp.70-76
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• 2012

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.683-684
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• 2004

The RF system for PEFP 20MeV proton linear accelerator is described. The RF system for 3MeV RFQ was already installed and operated to drive the RFQ. The klystron was tested up to 600kW itself and operated up to 350kW routinely. The HPRF dummy load was stabilized with the change of the coolant. Preparation of 20MeV DTL HPRF test has been completed. LCP and PLC system for klystron power supply was already prepared. Voltage fluctuation was measured during klystron test. Voltage control feedback loop seems to be re-adjusted.