• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.132-135
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• 2003

Solution chemistry, sorbate chemistry, and sorbent chemistry were widely investigated to find important factors that affect PAH sorption on mineral surfaces and to elucidate its microscopic mechanism. The solution chemistry, pH and ionic strength caused measurable change of HOC sorption reaction to minerals. The detectable change of Ka occurred at a pH region crossing the PZC (Point of Zero Charge) of each mineral. The PAH hydrophobicity, one of sorbate chemistry, was observed to have a strong correlation with PAM sorption to mineral. Mineral surface area was not found to be a predominant factor controlling PAH sorption. The mineral type might be more likely to play a crucial role in controlling the PAH sorption behavior. The CEC (Cation Exchange Capacity) of mineral, representing surface charge density, has meaningful correlation with regression slope of sorption coefficients (log $K_{d}$) versus aqueous activity coefficients (log Υ$_{w}$).).).

• Journal of Korean Society for Quality Management
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• v.38 no.4
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• pp.512-520
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• 2010

This research is the analysis of using structural equation method in order to investigate the cause and effect relationship among the elements related to the innovation activity and the degree of the influence on that, and in order to make sure the sequential processes into the meaningful management performance for improving the efficiency and effectiveness of a various of innovation activities performing in the domestic small and medium enterprise. To perform this research, we surveyed CEOs, managers, workers working for manufacturing business, we distributed 250 sheets totally and withdrew 206 sheets. we analyzed 169 sheets that we could use for this research using SPSS 15.0 and AMOS 18.0 program.

• Atmosphere
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• v.16 no.1
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• pp.49-53
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• 2006

The present study has examined interdecadal variations of the diurnal temperature range (DTR, daily maximum temperature minus daily minimum temperature) during the New Year season in Seoul for the period 1954-2005. Here, the average DTR for the New Year holidays (three consecutive days; one day before the New Year, the New Year day, and one day after the New Year) minus the average DTR for 14 days, 7 days before and 7 days after the New Year holidays, is defined for representing the New Year effect. The DTR index does not show notable trend until the late 1970s but shows obvious positive values afterward. For example, the difference of the average DTR between two periods (1980-2005 minus 1954-1979) is $0.65^{\circ}C$, which is meaningful at the 95% confidence level. This result demonstrates that intense human activity even for the limited period may provide climate impact in local regions. Its plausible causes are discussed.

• The Journal of Korean Medicine
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• v.19 no.2
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• pp.100-111
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• 1998

This study is designed to investigate the effects of Saengmaegsan extract on cultured myocardial cell sheets affected by oxygen tension change. The results were as follows : 1. Saengmaegsan meaningfully restored the cellular activity decrease in the cultured myocardial cells affected by high oxygen tension. 2. Saengmaegsan meaningfully lessened the degree of total protein decrease in the myocardial cells caused by high oxygen tension. 3. Saengmaegsan meaningfulJy refrained from syntetic decrease of 4-hydroxyproline in both low oxygen tension group and high oxygen tension group.

• Journal of Educational Research in Mathematics
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• v.10 no.1
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• pp.85-102
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• 2000

The concept of variables is central to mathematics teaching and learning in junior and senior high school. Understanding the concept provides the basis for the transition from arithmetic to algebra and necessary for the meaningful use of all advanced mathematics. Despite the importance of the concept, however, much has been written in the last decade concerning students' difficulties with the concept. This Thesis is based on research to investigate the hypothesis that LOGO programming will contribute to 6th grader' learning of variables. The aim of the research were to; .investigate practice on pupils' understanding of variables before the activity with a computer; .identify functions of LOGO programming in pupils' using and understanding of variable symbols, variable domain and the relationship between two variable dependent expressions during the activity using a computer; .investigate the influence of pupils' mathematical belief on understanding and using variables. The research consisted predominantly of a case study of 6 pupils' discourse and activities concerning variable during their abnormal lessons and interviews with researcher. The data collected for this study included video recordings of the pupils'work with their spoken language.

• Archives of Pharmacal Research
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• v.29 no.7
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• pp.582-586
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• 2006

Due to consumer reluctance to take synthetic drugs for nematode infections and the appearance of resistance to anthelminthic drugs, new drugs from natural products must be developed. Caenorhabditis elegans is one of the freely living nematodes and serves as a good model system for screening anthelminthic drugs. In this study, thirteen flavonoid derivatives were tested for anthelminthic activity and the relationships between their activities and structures were investigated. The structural information combined with the data for the larval growth inhibition of C. elegans provided meaningful structural insights in the search for new anthelminthic drugs.

• School Mathematics
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• v.13 no.2
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• pp.287-305
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• 2011

The goal of this study is to investigate reform directions of mathematics activity book which was introduced according to 2007 revised curriculum through literature analysis of introducing process. Futhermore, this study is to suggest the meaningful developing direction of new activity book according to the mathematics curriculum which is being developed now. To do this, first, the background of introducing activity book, developing direction, construction systems and the way to use it was analyzed. Second, teachers' response to the activity book on the basis of literature analysis was researched. Third, measures to improve activity book were investigated. In conclusion, reform direction of mathematics activity book was proposed in terms of developing research, goal, way to go, construction systems and questions arrangement.

• The Korea Journal of Herbology
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• v.21 no.4
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• pp.103-107
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• 2006

Objectives : This study was investigated to analyze the anti-oxidant activity of water and ethanol extracts from the Magnoliae Flos. Methods : The effects on electron donating ability (EDA), SOD-like activity and xanthine oxidase inhibition have been investigated the anti-oxidant activity for utilization as a natural material of cosmetics. Results : This study was investigated to analyze the anti-oxidant activity of water and ethanol extracts from the Magnoliae Flos. In the electron donating ability test, water and ethanol extract from Magnoliae Flos showed an effect of 75.6% and 83.5% at 1,000 ppm concentration, respectively. In the superoxide dismutase (SOD)-like activity, 1,000 ppm of water extract showed an effect of 45.2% and ethanol extract showed an effect of 64.2%. Xanthine oxidase showed a meaningful inhibitory effect of 68.8% in water extract and 23.2% at 1,000 ppm in ethanol extract. Conclusion : From these results, Magnoliae Flos showed the development possibility as a natural material of anti-oxidant cosmetics.

• Journal of Digital Convergence
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• v.16 no.10
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• pp.243-251
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• 2018

The purpose of this study was to examine whether fandom activity of adolescents mediates ego - resilience when affecting self - esteem. For this, data from the 7th year (2016) of the first 4 panels of the Korea Child and Youth Panel Survey were used and the questionnaire of 2,378 first - year high school students was used for the analysis. The results of the analysis are as follows. First, the fandom activity showed a positive predictive value of negative self - resilience. Second, the fandom activity predicted the self - esteem as a negatively. Third, ego - resilience predicts self - esteem statistically and significantly. Fourth, ego - resilience partially mediated the relationship between fandom activity and self - esteem. In other words, it is confirmed that the fandom activity directly lowers the self - esteem but indirectly decreases through the ego - resilience. This study can be meaningful in that it examines the effect of the fandom activity on the self - esteem of the adolescents and the process leading to it.

• The Journal of the Korea Contents Association
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• v.14 no.10
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• pp.137-150
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• 2014

This study analyzes the perception of the old age life effects on the preparation for old age plan for veterans who are somewhat isolated from our society in spite of the increasing importance of the old age plan due to the rapid population aging society in Korea. The result of the study shows that meaningful differences in terms of characteristics of sociology of population are rank, level of education, religion, composition of family members in old age life plan in two parts(economic, leisure), whereas only property in physical part has a meaningful difference. That indicates the result was reflected by the character of military. The study on how veterans' perception of the old life affects the old age plan applied two contrasting factors - 'the successful perception of old age life' and 'the perception of expected matters in old age'. That represents those factors(economic, leisure) made positive effects on preparation for old age plan, but not in physical part. 'Expected perception of matters' made regulation effect, but 'success of old age perception' didn't in terms of regulation effect of learning activity as part of the veterans vocational training programs.