• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.621-621
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• 2012

기존의 수력발전방식은 물의 위치에너지를 이용하므로 적합한 입지가 제한된다. 그러나 수류에너지를 이용한 발전방식은 기존의 수력발전과는 달리 물의 운동에너지를 이용하기 때문에 입지에 제한이 적으며, 물은 밀도가 크기 때문에 작은 유속으로도 많은 에너지를 생산할 수 있고,댐을 필요로 하지 않으므로 하천생태계 및 환경에 영향을 주지 않는 장점이 있다. 따라서 하천 뿐 아니라 기존 물관련시설의 미활용 방류수를 이용할 수 있으므로 수력잠재량이 매우 크다. 본 연구에서는 다목적댐 방수로의 수류에너지잠재량 산정을 위하여 유역면적이 $6,648km^2$이고 연평균 방류량이 약 $66.770m^3/s$인 충주댐을 선정하였다. 분석결과 충주 다목적댐의 방수로를 이용한 수류에너지 잠재량은 연간 약 373,687kWh로 산정되었다. 향후 하천생태계와 환경에 영향을 주지않는 재생에너지원으로서의 수류에너지 이용은 미활용 에너지의 적극 활용 측면과 미래전력 수요에 대한 중요한 원천으로써 재고되어야 할 것이다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2020.07a
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• pp.181-182
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• 2020

본 연구는 다문화청소년 패널데이터 3차년(2013년)부터 7차년(2017년)까지 패널조사 데이터를 활용하여 다문화청소년의 이중문화수용성이 성취동기에 미치는 영향에 있어 시간의 흐름에 따른 변화를 분석하고자 한다. 이를 위해 잠재성장모형을 이용한 이중문화수용성과 성취동기 간의 상관관계 및 인과적 관계를 규명하는 방법을 적용하였다.

• Journal of the Korea Society of Computer and Information
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• v.12 no.1 s.45
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• pp.231-242
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• 2007

This study was conducted to identify the relation of bottleneck and satisfaction factors in Korean succession companies. The final goal of this paper is finding some strategies and supporting system for Korean succession companies. According to the results of the study, we found four latent variables of the cause variables and two latent variables of the result variables. Three latent variables of the cause variables have an direct effect on two latent variables of the result variables.

• Bulletin of Korea Environmental Preservation Association
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• v.14 no.12
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• pp.5-9
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• 1992

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.197-197
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• 2023

본 연구에서는 2018년부터 2021년까지의 국가가뭄정보통계집 자료를 바탕으로 호서 지역 내 농업가뭄 피해 사례들을 심층분석하고, 당시 지원된 농업용수 공급량에 주목하여 실제 용수 공급에 영향을 미친 잠재적 요인들의 특성을 파악하였다. 먼저, 농업가뭄 피해를 가뭄 당시 실제 공급된 농업용수량으로 정의하고, 피해 민감도라는 개념을 새롭게 도입하여 잠재적 영향 요인들과 농업용수 공급량 간의 지역별 연관성을 분석하였다. 본 연구는 농업 환경과 기상 조건 관련 인자들을 잠재적 영향 요인으로 규정하고, 연도별 도시면적당 농경지 면적 비율, 도시인구수 대비 농업종사자 비율, 전체 용수 이용량 대비 농업용수 비율, 월별 강수량, SPI(-3, -6, -9 및 -12)를 대상으로 연구를 수행하였다. 이러한 인자들의 변화에 따른 실제 공급된 농업용수량의 변화 정도를 수치화하여 지역별 피해 민감도를 산정하였다. 이를 위해, 먼저 잠재적 영향 요인과 실제 공급한 농업용수의 전월대비 증감량을 2018년부터 2021년까지 월별로 계산하였으며, 최대·최소 정규화를 통해 0부터 1 사이의 값으로 수치화하였다. 앞서 언급한 월별 증감량의 비율을 바탕으로 4년간의 절대적 수치 변화 정도를 비교·분석하였다. 그 결과, 농업 환경 관련 인자들 중 전체 용수 이용량 대비 농업용수 비율이 상대적으로 피해 민감도가 큰 것으로 나타났으며 기상 조건 관련 인자의 경우, SPI-9에 대한 피해 민감도가 가장 높은 수준임을 확인하였다. 추후, 본 연구에서 제안한 방법을 바탕으로 다양한 요인들에 대한 피해 민감도 산정 결과들이 도출된다면 농업가뭄 피해 시 농업용수 공급의 적절성 여부를 판단하는 데 있어 유용한 정보를 제공할 수 있을 것으로 사료된다.

• Survey Research
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• v.10 no.3
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• pp.37-58
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• 2009

The purpose of this study were to identify the subgroups (i.e., latent classes) depending on early adolescents' change patterns in aggression and to test the effects of individual-background variables on determining the latent classes. For these goals, we applied Nagin's(1999) semi-parametric group-based approach to the Korean Youth Panel Study. Results showed that four latent classes were identified, which could be defined based on the patterns as low-level group, increasing group, intermediate-level group, and high-level group. By adding gender, self-control, parent attachment, teacher attachment, and the number of delinquent friends to the unconditional latent class model, we tested the effects of the variables on the latent classes. Multinomial logit analysis showed that gender, self-control, teacher attachment, and the number of delinquent friends were significant determinants of the latent classes. Findings from this study suggest the need to consider heterogeneity in the study of early adolescents' aggression to facilitate more refined targeting of intervention program.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.672-679
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• 2018

This study was conducted to predict the potential distribution and risk of invasive alien plant, Amaranthus patulus, in an agricultural area of South Korea. We collected 254 presence localities of A. patulus using field survey and literature search and stimulated the potential distribution area of A. patulus using maximum entropy modeling (MaxEnt) with six climatic variables. Two different kinds of agricultural risk index, raster risk index and regional risk index, were estimated. The 'raster risk index' was calculated by multiplying the potential distribution by the field area in $1{\times}1km$ and 'regional risk index' was calculated by multiplying the potential distribution by field area proportion in the total field of South Korea. The predicted potential distribution of A. patulus was almost matched with actual presence data. The annual mean temperature had the highest contribution for distribution modeling of A. patulus. Area under curve (AUC) value of the model was 0.711. The highest regions were Gwangju for potential distribution, Jeju for 'raster risk index' and Gyeongbuk for 'regional risk index'. This different ranks among the index showed the importance about the development of various risk index for evaluating invasive plant risk.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.278-291
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• 2021

This study performed a longitudinal research on the causal relationship between multidimensionality of problem drinking and poverty, and multidimensional deprivation meaning the inequality, focusing on gender difference. For this, this study examined the latent group of problem drinking change trajectory through the latent class growth analysis targeting total 3,770 men and 5,632 women by using the 6th-year Korea Welfare Panel Study data from 2013 to 2018, and then conducted the multinominal logistic regression analysis to verify the influence of multidimensional deprivation factors on this latent group. The main results of this study are as follows. First, the latent group of problem drinking change trajectory according to gender was classified into three latent groups in both men and women while the development aspect was different from each other. The male latent group with 'moderate level' or higher showed higher level of problem drinking than women. However, in case of 'drinking group with high level' according to gender, as time passed, the men tended to maintain it while the women tended to increase it. Second, in the results of examining the effects of multidimensional deprivation on the latent group of problem drinking change trajectory, the men with more experiences of social deprivation and the women with more experiences of social security deprivation showed the higher possibility to belong to the 'drinking group with high level' compared to the 'drinking group with low level'. Based on such results above, this study discussed the preventive/intervention measures for problem drinking according to gender.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.221-235
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• 2020

This study identified the latent groups according to smartphone addiction tendency and examined the factors affecting the latent group identification. The best-fitting LCA solution had three classes. The first group was 'non-academic stressed group, immersed in smartphone' It was characterized low scores on academic stress and average scores on smartphone addiction tendency. The second group was 'medium level academic stressed group, immersed in smartphone' which scored slightly above average in academic stress and smartphone addiction tendency. The third group was 'medium level academic stressed group, non-immersed in smartphone'. It showed higher scores than average in academic stress, but students with far lower scores in smartphone addiction tendency. Logistic analysis result showed that gender and grade were significant. This study is meaningful in analyzing academic related variable(academic stress) and mental health related variable(smartphone addiction tendency) to classify the groups according to patterns between the two variables and suggest appropriate intervention for each group in a convergence way.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.164-172
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• 2020

This study investigated the longitudinal transition of adolescents' psychological character profiles, which includes self-esteem, acculturative stress, depression, and social withdrawal, and the predictive effects of parental efficacy, families' support, and friends' support in multicultural families. The sample consisted of 1,188 adolescents in elementary school, who were re-examined in three years, when they were in middle school from the part of waves 2 and 6 of the Multicultural Adolescents Panel Study. A latent profile analysis identified three distinct profiles of psychological character among adolescents in elementary school and middle school: stable, social withdrawal, and unstable. As compared to elementary school, adolescents' psychological characteristics stayed stable and played critical roles on the latent classes. Parental efficacy, and supports from family and friends played critical roles on the latent classes. Specifically, as adolescents perceived full of supports from friends, they were more likely to make transitions to the stable group. Implications for intervention in multicultural families are discussed.