• Proceedings of the Korean Society of Crop Science Conference
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• 2004.04a
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• pp.290-291
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• 2004

• Proceedings of the Korean Society of Crop Science Conference
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• 2004.04a
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• pp.70-71
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• 2004

• Microbiology and Biotechnology Letters
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• v.39 no.1
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• pp.1-8
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• 2011

The antimicrobial effects of silver (Ag) ion or salts are well known. Recently, silver nanoparticle is attracting an interest in a wide variety of fields since it has been known to be safe and effective as an antimicrobial agent against a broad spectrum of microorganisms. Although silver nanoparticle has been applied to various kinds of products owing to its potent antimicrobial activity, the effects of silver nanoparticle on microorganisms and antimicrobial mechanism have not been revealed clearly. In this paper, we summarized the characteristics, antimicrobial activities and mechanisms, cytotoxicity and applicability of silver nanoparticle.

• 한국전산유체공학회:학술대회논문집
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• 1998.11a
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• pp.211-219
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• 1998

Propellants pressurized and fed into the combustion chamber undergoes the mechanical, chemical combustion processes. Along with their distinctive physical characteristics, propellant combustion is typically divided into the processes; injection, atomization, mixing, vaporization and chemical reaction. These processes assumed to happen in a serial manner are strongly coupled, thereby involves formidable physical complexities. In this study a numerical experiment is attempted to simulate the burning sprays due to OFO, FOF triplet / FOOF split doublet injectors. Based on Eulerian-Lagrangian frame, Navier-Stokes equation system for compressible flows is preconditioned with low Reynolds number $k-{\varepsilon}$ turbulent model and time-integrated by LU-SGS, and the sprays are described by DSF model with the characteristics initialized by experimentally determined spray characteristics. Simplified single global reaction model approximates heptane-air reaction. It was observed that FOOF split doublet injector shows better atmization with shortest residence and the FOF triplet injector produces better combustion performance.

• 한국전산유체공학회:학술대회논문집
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• 1998.05a
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• pp.128-137
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• 1998

In this numerical experiment, the preconditioned compressible Navier-Stokes equation is tested to analyze the laminar spray combustion. Sprayed flow field is formulated by Eulerian-Lagrangian system for the gas and liquid phases each. DSF(Deterministic Separated Flow) model was adopted for the sprays with the vortex model to describe transients of individual droplet heating. Simplified single global reaction model approximates methanol-air reaction with and without disk flame holder. The equation system is discretized by finite difference technique and time integrated by LU-SGS. Due to greatly simplified chemical reaction mechanism and the lack of experimental evidences, most of the efforts were devoted to show the applicability and robustness of preconditioned compressible flow calculation algorithm. Computation results in qualitatively reasonable combusting flow field, hence it is believed that further refinement are required to produce quantitatively accurate solutions.

• Proceedings of the KIPE Conference
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• 2008.10a
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• pp.100-102
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• 2008

As Utility interactive fuel cell systems are widely used, it is required for each power conditioning system(PCS) to have higher generating performance and more stable connecting characteristics. This study is focused to minimization of power losses and hence higher efficiency related to the new half bridge type 3-stage utility interactive PCS topology. The loss factor of half-bridge converter becomes only 1.2[%] under the rated load, and hence total efficiency is maintained to be higher as 91[%].

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.225-229
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• 2012

대기가 희박한 고고도 환령이나 급격한 선회를 위해 2차분사에 의한 추력벡터제어를 사용한다. 8개의 2차분사구를 갖는 고체로켓모터를 대상으로, 2차분사의 유량을 조절하는 밸브의 개도가 추력, 측추력 및 롤 모멘트에 미치는 영향을 해석적으로 연구하였다. 정상 상태의 3차원 Reynolds Averaged Navier-Stokes 식의 해를 구하였으며, 난류를 위해 Spalart-Almaras 모델을 사용하였다. 수치해석의 타당성을 평가하기 위해 실험 결과와 해석결과를 비교하였다. 밸브의 개도가 증가함에 따라 추력은 감소하나 측추력은 증가한다. 반면, 롤 모멘트의 경우, 밸브와 2차분사 파이프의 상호작용에 의해 개도에 비례하지 않는다.

• Biomolecules & Therapeutics
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• v.18 no.4
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• pp.420-425
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• 2010

The antifungal effects and action mechanisms of styraxjaponoside A and B were investigated. Devoid of hemolytic effect, the compounds had significant effect against several human pathogenic fungal strains, with energy-independent manners. To understand the action mechanisms of the compounds, the flow cytometric analysis plotting the forward scatter and the side scatter, $DiBAC_4$(3) staining and DPH fluorescence analysis were conducted. The results indicated that the actions of the compounds were dependent upon the membrane-active mechanisms. The present study suggests that styraxjaponoside A and B exert their antimicrobial effects via membrane-disruptive mechanisms.

• Journal of Popular Narrative
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• v.25 no.2
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• pp.279-302
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• 2019

This paper introduces Youngju Ryu's Writers of the Winter Republic: Literature and Resistance in Park Chung Hee's Korea, and examines its significance and limitations. The book examines the relationship between literature and politics during the Park Chung-hee Yushin era, focusing on Yang Sŏng-u, Kim Chi-ha, Yi Mun-gu, Cho Se-hŭi, and Hwang Sok-yong. The books starts by describing the relationship between the U.S. hegemony and the Park Chung-hee regime during the Cold War. The book shows how poets like Yang and Kim fought against the Park Chung-hee regime based on poems, trial records and memoirs, while it describes novelists such as Yi's resistance by how novels envisioned a community against the Park administration based on the keyword "neighborhood." This is significant in that it describes how literature from the Park Chung-hee era was able to stand on the front lines against the regime. However, it is regrettable that because the book adopts a heroic tale to describe their lives and literature, these are illuminated in a somewhat flat way. Also it is noteworthy that the lives and works of novelists after the 2000s were illuminated, but Yang and Kim's life and literature were not described. Furthermore, it is regrettable that women writers were not mentioned and its concept of "politics" is rather shallow. Overall, this book is very significant in that it introduces the relationship between Korean literature and politics in the Korea of the 1970s with rich data and a beautiful style, as well as allowing Korean studies researchers to reflect on the future of Korean studies.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.256-256
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• 2012

2011년 태국 차오프라야 강 유역($160,813km^2$)에서 발생한 홍수에 의해 많은 피해가 발생했다. 태국 홍수는 2011년 7월 말부터 3개월간 내린 집중호우로 중부지방에 50년 만에 최악의 자연재해를 맞이하였다. 태국 북쪽 지역에서 난 강과 핑 강의 범람을 시작으로 태국 중앙 지역을 흐르는 차오프라야 강의 수위는 상류의 홍수가 하류로 내려옴에 따라 범람하여 수도 방콕까지 침수되었다. 본 연구에서는 홍수범람시 시공간적 침수상황이 파악 가능한 Terra MODIS (Moderate Resolution Imaging Spectroradiometer) 영상을 이용하여 태국 차오프라야 강 유역의 홍수에 의한 침수지역을 추정하고자 하였다. 2011년 7월 29일에서 2012년 1월 9일까지의 500 m 해상도인 MODIS product MOD09 (Surface Reflectance) 8일 합성 영상을 수집하고 식생지수 (EVI; Enhanced Vegetation Index), 지표수분지수 (LSWI; Land Surface Water Index))와 DVEL지수 (Difference Value between EVI and LSWI)를 이용하여 홍수범람 지역과 수역관련지역을 정보화 기법을 제시하였다. 본 연구의 결과는 홍수 범람지역의 자료를 정보화하고 그 결과를 정량적으로 제시하는 방법으로 활용될 수 있으며, MODIS 자료의 이용은 시공간적 하천 홍수범람지역 탐지의 가능성을 알 수 있었다.