• 대한조선학회논문집
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• 제49권6호
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• pp.461-468
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• 2012

In this study, a Cartesian-grid method based on finite volume approach is applied to simulate the ship motions in large amplitude waves. Fractional step method is applied for pressure-velocity coupling and TVD limiter is used to interpolate the cell face value for the discretization of convective term. Water, air, and solid phases are identified by using the concept of volume-fraction function for each phase. In order to capture the interface between air and water, the tangent of hyperbola for interface capturing (THINC) scheme is used with weighed line interface calculation (WLIC) method which considers multidimensional information. The volume fraction of solid body embedded in the Cartesian grid system is calculated using a level-set based algorithm, and the body boundary condition is imposed by a volume weighted formula. Numerical simulations for the two-dimensional barge type model and Wigley hull in linear waves have been carried out to validate the newly developed code. To demonstrate the applicability for highly nonlinear wave-body interactions such as green water on the deck, numerical analysis on the large-amplitude motion of S175 containership is conducted and all computational results are compared with experimental data.

• 한국자원식물학회지
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• 제26권1호
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• pp.75-83
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• 2013

본 연구는 점차 사라져가는 큰조롱의 유전자원을 보호하고 이용하고자 종자 발아 기술과 육묘기술 개발을 위해 종자 침지 처리 온도, $GA_3$ 농도, 트레이 및 토양 종류, 차광처리에 따른 큰조롱의 발아율과 생육특성을 조사하였다. 종자발아는 $20^{\circ}C$에서 $GA_3$ 100 ppm에 침지한 처리구에서 가장 높은 93% 발아율을 보였다. 묘소질 특성은 50구 트레이에서 가장 뛰어났으며 생리적 묘소질 특성은 $20^{\circ}C$에서 $GA_3$ 10 ppm에 침지 처리 한 종자를 TKS 토양이 충진된 128구 트레이에 파종한 조건에서 가장 뛰어났다. 따라서 큰조롱의 묘소질과 생리적 묘소질을 종합하고 경제적인 측면을 고려하면 128구 트레이 혹은 200구 트레이의 TKS, TKS+펄라이트 및 TKS+왕겨 처리구에서 4월 중순에 파종 후 30~ 45일 간 육묘하면 초장과 근장이 각각 10 cm 이상되고 엽수가 8 매 이상 되는 우량한 묘를 획득할 수 있었고 이를 본 밭에 이식이 가능한 것으로 보여진다.

• 한국축산시설환경학회지
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• 제1권1호
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• pp.9-19
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• 1995

This study was carried out to investigate the effect of sawdust bedding barn on manure handing, management labour and physiological aspect of dairy cows, and then to establish the criteria on the optimum utilization method of sawdust bedding barn. 46 tie stall barns and 49 sawdust bedding barns were surveyed to cmopare the milk productivity between two different barns, and also 5 tie stall barns, 15 sawdust bedding barns and 1 rice hull bedding barn were selected to study the utilization situation of sawdust barn in Kyung-Ki province area. The major results obtained were as follows; 1. The roof material of sawdust barn were consisted of 66% vinyl house, 23% PVC light and 11% slate and galvanum coated tin. Most of the floor structure was earth ground with the rate of the approximately 82%. 2. The average occupied area of sawdust bed per cow was 15.2 $m^2$, depth that 30 cm and the utilization period was 12 months. 3. Milk Yield was significantly higher at sawdust barn than at tie stall barn(P<0.01). Bacterial and somatic cell count in raw milk were less at the sawdust barn than in tie stall barn. However, there was not significance difference between two barns. 4. The labour hour needed to cow management in the sawdust barn was approximately 48% of that of tie stall barn. 5. The temperature and moisture content measured in sawdust bed were closely affected by seasonal ambient temperature. The skin and hair of cow were much cleaner at the PVC light roofed sawdust barn than any other roof materials. 6. The additives used for improving of fermentation did not show any effect on temperature and moisture content in sawdust bed. When the ambient temperature was $30.4^{\circ}C$, the surface temperature of measured 1 cm above the sawdust bed was $12.2^{\circ}C$ lower and the temperature of 100 cm above the sawdust bed was $2.4^{\circ}C lower under shading net facility than that of vinyl roofed one.7. The hoof length of miking cow was 7.95 cm in tie stall and 9.19 cm in sawdust barn with high significance (P<0.01). And disease occurence such as mastitis and foot-rot tended to decrease in the sawdust barn. 8. The number of total bacteria and coliform bacteria were less in the sawdust bed compared with earth ground resting area. And a parasite strongyloides papillosus was detected but without any infected cow. 9. The nitrate($NO_3N$) content in non-roofed earth ground resting area and earth ground under the sawdust bed was likely to pollute the ground water. 10. In economic point of view, rice hull bedding barn was the cheapest among different systems. And in the sawdust bedding barn PVC light + slate roofed barn was most desirable, and vinyl roofed one the least.

• 한국식품과학회지
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• 제50권5호
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• pp.549-554
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• 2018

본 연구에서는 일반 메밀과 쓴 메밀의 제분 분획 별(겉껍질, 겨, 가루) 에탄올 추출물의 항산화 성분 함량을 분석하고, 항산화 활성을 시험관과 세포 수준에서 확인하였다. 그 결과, 일반 메밀보다 쓴 메밀에서 총 폴리페놀 및 총 플라보노이드 함량이 월등히 높았으며, 항산화 물질로 주된 성분은 루틴으로 확인되었고, 에탄올 추출과정에서 루틴이 퀘세틴으로 일부 분해되는 것으로 나타났다. 또한 식용 부위인 가루 분획보다 겨 분획에서의 항산화 성분 함량이 높은 것으로 분석되어 겨 분획의 항산화 기능성 소재로 개발의 필요성을 제시하였다. 한편 시험관 및 세포수준에서 항산화 효과를 확인한 결과, 일반 메밀보다 쓴 메밀에서의 항산화 활성이 유의적으로 높았으며, 특히 쓴 메밀 겨 분획의 항산화력이 우수한 것으로 나타났다. 메밀 추출물을 산화스트레스 유발 전, 후 처리한 경우 모두에서 항산화 활성이 유사한 경향으로 나타나, 메밀 추출물의 산화스트레스 예방 및 치료 효과 가능성을 제시하였다.