• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.515-516
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• 2009

Recently, A lot of roads, railroads and tunnels are constructed for development of industrialization and efficient use of national land. So, we have focused on to figure out the best combination between Slag powder and Mortars with Accelerator to repair of tunnel structure.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.61-61
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• 1995

1993년 국내토양으로부터 분리동정된 Streptomyces속 균주중 항종양성이 우수한 균주 3주(DKM104, DKM117, DKM409)를 선정하고 이들을 대량 배양하여 종양억제인자를 분리하고 시험관내 종양세포 독성능 및 생체내 항암활성능과 이들 물질생산과 PLASMID DNA와의 관련성, $LD_{50}$등을 시험하여 새로운 항종양물질의 개발을 목적으로 하였다. 분리선별균주의 배양조건을 확립하였으며 배양여액을 국성이 적은 유기용매로부터 큰쪽으로 단계적으로 유효성분을 추출하여 Gel Chromatography를 이용하여 유효성분을 분획하였다. 시험관내 항종양능 시험은 MTT colorimetric검정법을 이용하여 $IC_{50}$값을 산정하였으며 생체내 항종양능은 마국의 NIC에서 권장하는 tumor panel system에 따랐다. 선정된 균주의 plasmid 분리는 alkalin lysis법을 채택하였으며 agarose gel electrophoresis로 plasmid profile을 시험하였다. Novobiocin등을 이용하여 Curing test를 시행하였고 독성실험은 $LD_{50}$량을 구해 항암효과 측정시에 Maximum dost로 투여하였고 최고용량을 기준으로 일정한 공비를 적응하여 3단계의 투여량을 설정하였다.(중략)

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2002.10a
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• pp.224-228
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• 2002

To study the trafficability on soft and cohesive benthic terrain, a soil bin is designed and constructed. The information of shear strength of pacific seafloor and the results of dimensional analysis of vehicle-train system are used as basic datum for concept design of soil bin. Cohesive benthic terrain is modeled by means of bentonite-water mixture. The shear strength of the mixture is measured by motorized shear meter. Several facilities are constructed for mixing and evening modeled soil, transporting vehicle model. The shear strength in soil bin is investigated for depth, age and velocity. The result of this study is used as basic information to the experiment, study for development of crawler on benthic terrain.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.507-513
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• 2002

본 연구에서는 정밀농업 구현을 위해 필수 불가결의 요소인 데이터베이스 구축의 필요성에 착안하여 공간 및 속성 데이터 구축 알고리즘의 설계와 데이터베이스를 구성하는 테이블의 스키마 설계를 통해 공간 및 비공간 데이터를 구축하고 구축된 데이터베이스와의 통신을 통해 농작업 기계의 위치에 따른 토양 속성값을 추출해 내는 과정을 보임으로써 의사결정 지원시스템으로서의 기능을 시뮬레이션을 통해 제시하였다. 연구에 사용된 공간 및 비공간 데이터 구축에 있어서의 수작업은 작업자로 하여금 노동 소모적인 작업을 요구하므로 차후의 연구에 있어 보다 자동화되고 개선된 알고리즘의 개발이 요구된다. 또한 구축되어야 하는 경작지의 규모가 커지고 비공간 데이터의 양이 많아지게 되면 데이터베이스내의 검색 성능 향상에 대한 고찰 또한 병행되어야 할 것으로 판단된다.

• Journal of the Korean Society of Groundwater Environment
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• v.6 no.4
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• pp.206-212
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• 1999

In order to evaluate the applicability of steel mill slag as a AMD (Acid Mine Drainage) neutralizer and to compare capacity of slag with that of limestone lab scale experiments were conducted. The fixed treatment experiments of AMD with slag and limestone separately for 24 hours under the stagnant condition showed that slag has higher capacity of pH increase and removal of Fe. Al and other trace elements. During the 10 days continuous step experiment the pH has been maintained and any decrease in the removal capacity of Fe and Al has not bun observed. In the trace element removal experiment slag showed higher capacity for removal of Ni, Co. Cu and Zn than limestone. The removal of trace element was more effective in AMD than in distilled water that the pH was adjusted to the same level of AMD (synthetic acid solution). It means that Fe and Al in AMD adsorbed trace elements during or after precipitation as oxide forms. In the size effect experiment, the slag of the smaller size with larger specific surface area exhibited higher capacity of pH increase and removal efficiencies of Fe. Al and other trace elements.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.3
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• pp.261-268
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• 2016

Tuned Liquid Dampers(TLD) are energy dissipation devices that have been proposed to control the dynamics response of structure. The TLD has been shown to effectively control the wind response of structures. However, controlling responses of structures with TLD under seismic loads are not fully investigated. The objective of this study is to evaluate the seismic performance of single degree of freedom(SDF) with TLDs having various tuning and mass raitos. For this purpose, analytical studies are conducted. Different soil conditions are considered in this study. As a result, performance of TLD, appeared diffrently depending on the natural period, damping ratio of the structure. Also TLD tuning ratio appeared differently.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.4
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• pp.279-291
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• 2005

To support the design concept and the performance assessment of the cover system for low- and intermediate-level radioactive waste(LILW) disposal facility, a pioneering study is conducted for the tomb of historical age. Research status of the art are investigated and the characteristics of tomb cover are summarized based on the preservation status of historical remains. On-site soil samples are prepared and their unsaturated hydraulic conductivities are measured by an one-step outflow method. Visiting the excavation site of historical tomb and communication with Korean archeological society are required for the further understanding and for the extension to the radioactive waste disposal research.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.977-977
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• 2012

하천의 유량 측정은 대부분 홍수 예보지역, 댐 상류지역, 대하천 및 유역내 주요지점을 위주로 수행되고 있으나, 중소하천과 소유역에 대한 관측자료는 전무한 실정이다. 그로 인해 중소하천과 소유역 등 미계측 유역에 대한 유량 산정에 어려움이 있다. 본 연구에서는 미계측 유역에 대한 적합한 유량 산정방법의 검토를 위해 미호천의 소유역인 증평유역을 대상으로 9개의 개념적 강우-유출모형(3개의 토양저류모형과 3개의 유역유출모형의 조합)을 적용하였으며, 이에 대한 적용성 검토를 위해 국내 홍수량산정에 많이 활용되고 있는 HEC-HMS 모형으로 비교평가를 실시하였다. 이를 위하여 총 6개의 단기 홍수사상을 Monte Carlo 분석(Nash Sutcliffe Efficiency, NSE*)의 목적함수를 통하여 모형 매개변수의 검정 및 검증을 수행하였다. 두 모형의 단기 유출 모의 결과 검정에서 HEC-HMS는 목적함수값 0.06~1.44(NE S*)의 모형성능을 보여주었으며, 개념적 강우-유출 모형은 0.00~0.66(NES*)의 모형성능을 나타내었다. 개념적 강우-유출 모형과 HEC-HMS모형의 매개변수 최적화를 통한 검증 결과 HEC-HMS는 0.25(NES*)의 목적함수 값을 나타내었고, 9개의 개념적 강우-유출모형은 0.14~0.83(NES*)의 목적함수 값을 나타내었다. 이 중 CWI-3PAR, CWI-2PMP, PDM-3PAR와 PDM-2PMP 모형이 0.16~0.26(NES*)으로 우수한 성능을 보이며, HEC-HMS 모형의 첨두유량 과소평가에 대한 문제점을 해결하였다. 이를 통하여 CWI-3PAR, CWI-2PMP, PDM-3PAR와 PDM-2PMP 모형이 증평유역의 지역화를 위한 단기사상 강우유출모형으로 적합하다고 판단된다. 향후 연구유역을 확장하여 추가적인 연구를 통해 일반화된 결론을 얻을 필요가 있다.

• Journal of Korea Water Resources Association
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• v.56 no.12
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• pp.855-869
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• 2023

Low Impact Development (LID) technology has been attracting attention as a countermeasure to solve frequent flood damage in urban areas. LID involves recovery of the natural circulation system based on infiltration and storage capacity at the site of rainfall runoff, to protect the aquatic ecosystem from the effects of urbanization. Bioretention as an element of LID technology reduces outflow through storage and infiltration of storm water runoff, and minimizes the effects of non-point pollutants. Although LIDs are being studied extensively, the amount of quantitative research on small watersheds with bioretention has been inadequate. In this study, a bioretention model was constructed in a small watershed using Korea-Low Impact Development Model (K-LIDM), which was conducted quantitative hydrologic analysis. We anticipate that the results of the analysis will be used as reference data for future bioretention research related to watershed characteristics, vegetation type, and soil condition.

• Journal of Biosystems Engineering
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• v.14 no.2
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• pp.67-79
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• 1989

This study was conducted to investigate the applicability of true model theory for pull prediction in a powered lugged wheel-soil system and to examine the possibility of using principles of similitude in investigating the dimensions of soil parameters pertinent to a powered lugged wheel-soil system concerning the pull prediction. The following conclusions were derived from the study; 1) The pull of prototype wheels proved to be predicted by those of the model wheels for the range of the dynamic weight tested. The pull curves of models and prototype were respectively very similar in the shape. From this basic knowledge, it was enabled to apply the similitude theory to the performance prediction of the true model. 2) A conditional equation which can be used for the prediction of pull of prototype by model test was derived as follows. $n_f=n_1^{-b}$ where $n_f$ : force scale = $w/w_m$ $n_1$ : length scale = ${\ell}/{\ell}_m$ b : exponent on the length dimension of the soil property ${\alpha}$ The range of the numerical value of b, which was determined by the least square method, was found to be -2.0~-2.6. 3) Considering a relatively wide variation of b values in the pull prediction, b is considered to be a function of many variales. Thus it was concluded that there are several soil properties which are pertinent to the powered lugged-wheel-soil system concerning the pull prediction, and these soil properties may have the different effects on the pull of model and protytype wheels, to give the different dimension on the soil parameters.