• Title/Summary/Keyword: Kyung Keun

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Synthesis of Acyclonucleosides (2) -Synthesis of 2', 3'-disubstituted Secouridines- (Acyclonucleoside 류의 합성(2) -2',3'-disubstituted secouridine의 합성-)

  • Yang, Jae-Wook;Hong, Kyong-Aie;Han, Hyo-Kyung;Chun, Moon-Woo;Chung, Won-Keun
    • YAKHAK HOEJI
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    • v.33 no.5
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    • pp.296-299
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    • 1989

  • The synthetic study of 2', 3'-diazido and difluoro secouridines toward development of new antiviral agents is discribed. These acyclic nucleosides were synthesized from uridine by the method of ring opening reaction of sugar moiety.

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Examination of Concrete Hydration Heat According to the Application of Synthetic Resin Formwork (합성수지 거푸집 적용에 따른 콘크리트 수화열 검토)

  • Nam, Kyung-Yong;Kim, Seong-Deok;Choi, Suk;Yang, Keun-Hyeok
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.06a
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    • pp.153-154
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    • 2020

  • The purpose of this paper is to examine the characteristics of heat and hydration of concrete according to formwork materials. As a result of the experiment, it was found that there were no problems such as concrete heat loss and delay in hydration reaction due to the use of synthetic resin formwork.

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A Study on Efficient Machine Learning Method Using Random Search and Genetic Algorithm Search (랜덤 탐색과 유전 알고리즘 탐색을 이용한 효율적 기계학습 방법 연구)

  • Lee, Kyung-Tae;Kwon, Young-Keun
    • Annual Conference of KIPS
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    • 2020.05a
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    • pp.494-496
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    • 2020

  • 기계학습 모델을 이용한 분류 및 회귀 문제해결에는 다양한 전처리 알고리즘 및 기계학습 모델이 활용된다. 하지만 합리적인 성능을 위해서는 주어진 데이터에 따라 적절한 알고리즘 조합에 대한 탐색 및 최적화 과정이 펄수적이다. 본 논문에서는 최적의 알고리즘 조합을 탐색하는 방법 중 랜덤 탐색과 유전 알고리즘 탐색 방법을 구현하고 8가지 데이터에 대한 성능 비교를 통해 여러 기계학습 모델을 고려하는 탐색 방법의 필요성을 보인다.

  • https://doi.org/10.3745/PKIPS.y2020m05a.494 인용 PDF

Association between the Physical Activity of Korean Adolescents and Socioeconomic Status (우리나라 청소년의 신체활동과 사회경제적 변수와의 관련성)

  • Oh, In-Hwan;Lee, Go-Eun;Oh, Chang-Mo;Choi, Kyung-Sik;Choe, Bong-Keun;Choi, Joong-Myung;Yoon, Tai-Young
    • Journal of Preventive Medicine and Public Health
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    • v.42 no.5
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    • pp.305-314
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    • 2009

  • Objectives : The physical activity of Korean adolescents and its distribution based on social characteristics have not yet been fully assessed. This study intends to reveal the distribution of physical activity by its subgroups and offer possible explanatory variables. Methods : The 3rd Korea Youth Risk Behavior Web-based Survey was analyzed for this study. The appropriateness of physical activity was defined by Korea s Health Plan 2010 and physical inactivity was assessed independently. Family affluence scale, parents education levels, subjective economic status, grade, and school location were considered explanatory variables. All statistical analysis was conducted using SAS ver. 9.1. Results : The proportion of participants engaging in vigorous physical activity was high in males (41.6%), at a low grade (38.5%), within the high family affluence scale group (35.5%). The distribution of participants engaging in moderate physical activity showed similar patterns, but the overall proportion was lower (9.8%). Low family affluence and students with lower subjective economic status reported a higher prevalence of physical inactivity. In multiple logistic regression analysis for physical activity, significant factors included family affluence scale (p<0.05). For physical inactivity, family affluence scale, parents education levels, and subjective economic status were included as significant factors (p<0.05). Conclusions : The results suggest that the physical activity and inactivity of adolescents may be affected by socioeconomic variables, such as family affluence scale. This implies the need to take proper measures to address these socio-economic inequalities.

  • https://doi.org/10.3961/jpmph.2009.42.5.305 인용 PDF KSCI