• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.508-513
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• 2000

In an attempt to evaluate the fertilizer of sediments obtained from coastal farming areas, chemical composition, bacteriological quality and heavy metals in the sediments alkalized by quicklime and magnesium hydroxide were analyzed. The optimum conditions of alkalization were also measured. A perfect reaction was possible by the addition of quicklime of $30{\%}$ at the rate of $25{\%}$ of sediment and $100{\%}$ of livestock wastes. According to the classification standard for compost constituent by Higgins, all composts had the intermediate or high grade in $T-N, K_2O,\;CaO\;and\;MgO$, but below the low grade in $P_2O_5$, Stabilization by quicklime and magnesium hydroxide has been known to inhibit bacterial decomposition of organic matter and activity of pathogenic organisms. In this study, raising pH of stabilized sediments to 12 for 2 hours (PSRP rriteria of EPA) allowed $99.9{\%}$ of coliform group, fecal group and viable cell count to be reduced. As a result, sediments of coastal farming areas are likely to be used to produce the organic fertilizer by alkaline stabilization.

• Korean Journal of Mineralogy and Petrology
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• v.33 no.4
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• pp.391-405
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• 2020

Leaching chracteristics of Andong-dam sediment was conducted for heavy metal and nutrients. Five mixed sediment samples were prepared and leaching was conducted under aerobic and anaerobic condition for 60 days. Cd, Cu, Pb, Cr, Zn, Hg, As, Fe, Mn, phosphorus, and nitrogen were analyzed at each sampling time. The leaching rate of phosphorus was higher in anaerobic condition comparing with that of under aerobic condition. Some samples showed higher than the water-quality level IV. In case of As and Cd which showed highest contamination level in the sediment, leached concentration were 0.028 mg/L and 0.003 mg/L in maximum, respectively. The leached concentration is below than the lake water quality standard of Korea. Other heavy metals including Cu, Pb, and Cr also showed similar trend. Five step sequential extraction showed that easily extractable 1-2 step portion such as ion-exchangeable and adsorbed one was less than 10% and the most of the portion was residual. For As and Cd, the residual portion were 80% and 95% respectively indicating the risk by the heavy metal leaching into the lake for a short period was not high in comparing with the contamination levels.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.02a
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• pp.360-365
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• 2003

미곡종합처리장은 개소 당 평균 30억이 투자되는 방대한 시설로 수확된 산물상태의 벼를 수집ㆍ건조ㆍ저장ㆍ가공 및 포장공정이 일괄적으로 처리되는 농업의 첨단기술이 결집된 시설이라 할 수 있다. 미곡처리장은 약 80개의 단위기계와 100여종의 부대시설로 구성되어 있다. 미곡종합처리장은 거의 모든 과정이 중앙제어기에 의해 제어 가능하다. 그러나 미곡종합 처리장의 상온통풍건조시설은 기상조건, 투입벼의 함수율 및 반입량에 따라서 송풍기와 히터의 운전방법을 달리해야 하며, 또한 투입벼의 함수율에 따라서 벼의 퇴적고를 달리해야 하는 등 시설의 운전에 세심한 주의가 필요하다. (중략)

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.192-195
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• 2008

Conventional gas deposits consist of pressurized gas held in porous and permeable reservoir rocks and its recovery takes place where the natural pressure of the gas reservoir forces gas to the surface. But gas hydrate is a crystalline solid, its prospects require reservoir rock properties approprate porosity, permeability with mapping of temperature and pressure conditions to define the hydrate stability zone. In this study, we have carried out to investigate the dissociation characteristics of methane hydrates and the productivities of dissociated gas and water with depressurization scheme. Also, it has been conducted the flowing behavior of the dissociated gas and water in porous rock and the efficiency of the production.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.991-995
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• 2010

충주댐 유역을 대상으로, SWAT-K 모형의 적용을 통해 신뢰성 있는 장기간의 유량 및 수질모의자료를 기반으로 오염물질의 거동 특성을 파악하는 한편, 각 하천구간내 오염물질의 침식과 퇴적, 생물학적 변환 및 자정작용 등을 고려한 하천구간별 유달율을 산정하였으며, 각 하천구간별 유달 특성을 이용하여 점원 비점원에 의한 배출부하량 및 토지이용별(논 밭 산림) 배출부하량이 유역 하류측 충주댐 지점에서의 총 유달부하량에 미치는 영향을 평가하였다. 오염원별 기여도 분석 결과, 전체 유사량의 84%, 총질소의 93%, 총인인 92% 정도가 비점오염원에 의한 영향으로 나타났으며, 토지이용별로는 유사나 총인은 밭의 기여도가 높게 나타난 반면, 총질소는 유역내 면적비중이 큰 산림에 의한 영향이 가장 큰 것으로 나타났다.

• Journal of the Korean Society for Marine Environment & Energy
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• v.14 no.3
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• pp.163-175
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• 2011

Though polycyclic aromatic hydrocarbon compounds (PAHs) in marine sediment has been produced by many colleges and institution in Korea, it is difficult to compare PAHs data in a study area with those in other areas due to the lack of confidence for the quality of data from the other organization. Therefore, we suggested the protocol for PAHs analysis in marine sediment through examining the method of PAHs analysis described in over twenty scientific papers and reports. When a known amount of 23 PAHs were spiked into a sediment and anlyzed following this new protocol, very good recoveries were obtained. In addition, for college and institution with their own method to analyze PAHs can keep producing PAHs data without exchanging to this new PAHs protocol, the method to get a full confidence through the QA/QC for the PAHs data produced by these organization is included to the protocol.

• Journal of the Korean Geographical Society
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• v.46 no.1
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• pp.1-19
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• 2011

The physical and chemical characteristics of loess-paleosol sequence in Jeongjang-ri, Geochang basin are examined using the magnetic susceptibility measurement, grain size analysis, OSL age dating, major, rare earth and trace elements analysis. The grain size characteristics of the loess-palesol sequence are obviously different from those of river sediment forming river terrace deposits and the Chinese Loess Plateau. The loess-paleosol sequence consisting of L1, L1LL1, L1S1, L1L2, S1 and L2 from top to bottom is estimated to MIS 2~MIS 6 and the river terrace to MIS 7. The compositions of major, rare earth and trace elements indicate that the sequence show more weathered characteristics than the Chinese Loess Plateau and originated from the Chinese Loess Plateau. These features are in harmony with the previous studies in Korea.

• Journal of Animal Environmental Science
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• v.9 no.2
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• pp.113-122
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• 2003

This on­farm study was conducted to evaluate the effect of feeding deepstacked broiler excreta­saw dust­rice hulls(DBSR) pellets on feed intake, production and economy of growing Hanwoo steers and Holstein bulls. Formulated mix and rice straw were replaced at 16％ and 48％ levels for growing Hanwoo steers(6 wk of feeding period) and at 4％ and 18％ levels for Holstein bulls(12 wk) with DBSR pellets. Control and treated diets were formulated to be isoenergetic and DBSR pellets were fed ad libitum. Palatability of DBSR pellets turned out to be favorable. Compared with the control group, feeding DBSR pellets did not affect body weight gain, average daily gain and feed efficiency(P＞0.05). Feed cost per gain was reduced by 18.5％ for Hanwoo steers and 3.5％ for Holstein bulls. Feeding DBSR pellets to Holstein bulls did not affect carcass weight and grades of meat yield and quality. These results indicate that deepstacked cage broiler excreta mixture may be effectively used as a feed ingredient for growing ruminants.

• Journal of the Korean Geotechnical Society
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• v.19 no.4
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• pp.257-264
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• 2003

Bulking change between sediments and dredged soils occurs when dredged soils are fully disturbed by dredging process and settled down to stabilized conditions in the basin. Bulking of dredged soils are affected by chemical injection, coagulant and flocculant, to speed up settling process of the suspended solids. In this paper, bulking changes of dredged soils are investigated by experimental works regarding injection effects of the coagulant and flocculant. Dredged sediments were sampled in the lagoon located at the East Coast, and the bulking change of dredged soils is quantitatively analysed by changing the clay content and the amount of the coagulant and flocculant. The optimal amounts of the coagulant and flocculant are determined based on minimal bulking change due to coagulant and flocculant injection. From the experimental results, the bulking of dredged soils increased 1.69 times on the average and the bulking change rate slightly increased as clay content increasea due to injection of the coagulant and flocculant.

• 한국해양학회지
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• v.21 no.2
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• pp.92-100
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• 1986

Laboratory investigations of physical (density and porosity), acoustic (velocity and velocity anisotropy), and electrical (resistivity and resistivity anisotropy) properties in deep-sea carbonate sequences at DSDPsites 288 and 289 in the western equatorial Pacific were made and correlated as a function of diagenesis. Profile of resistivity shows almost a mirror image of velocity indicating that electrical resistivity can be a useful variable to determine the diagenetic stage. Some fluctuations in acoustic and electrical properties near the zones of cherty and siliceous limestones for both sites imply significant changes in pore geometry due to interbedded silica. The significantly reduced pore throat size by the presence of silica which provides excess calcium carbonate to adjacent pore spaces is partly responsible for several jumps in acoustic and electrical properties of the zones. These observed geophysical data are interpreted as the result of silica diagenesis influencing carbonate diagenesis.