• 한국연초학회지
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• 제23권1호
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• pp.5-11
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• 2001

Experiments were conducted to evaluated the sucker control efficiency of several suckercides and their combinations for flue-cured tobacco in Korea. In 1999, Flumetralin(Prime+, P+), Butralin(B), Fatty alcohol(FA, n-decanol 85%), pottasium salt of maleic hydrazide(MH), tank mix of MH with P+ (MH·P+), and another tank mix of MH with FA(MH·FA) were applied after topping, respectively, then sucker number and sucker dry weight were investigated on the 30th and 50th day from treatment. Sucker number and dry weight were significantly lowered by P+, B, FA and MH·P+ applications compared with those of MH and MH·FA for both investigated periods. A significant reduction in sucker number and dry weight was observed in P+, B, and MH·P+ applications. FA treatment was not so much effective in sucker control as P+. In 1999 and 2000, several suckercides and tank mixes of their combinations were applied first at button stage and second after topping, respectively, to compare the effects of sucker control on yield, price index and chemical components of cured leaves. Compared to the standard method of FA 30x at button stage followed by MH40x application after topping(FA 30x + MH 40x), sucker number and dry weight decreased by [FA 30x (or P+ 1%] or [FA 30x(or B 1.5%) + MH 60x·B 1.5%] treatments, even at reduced MH levels. But yield, price index and chemical components of cured leaves were not differed among treatments.

• 정보처리학회논문지B
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• 제18B권1호
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• pp.39-44
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• 2011

본 논문에서는 최근 Xin-She Yang에 의해 소개된 반딧불이 알고리즘(FA)에 휴리스틱을 적용하여 개선하는 방안을 제안한다. 또한 이를 위하여 기존의 FA를 이와 유사한 문제영역의 알고리즘인 Particle Swarm Optimization(PSO)와 정확도 측면, 수렴 시간 측면, 각 입자의 움직임 측면에서 비교 분석한다. 비교 실험 결과, FA의 정확도는 PSO보다 나쁘지 않았지만, 수렴 속도는 느린 것으로 나타났다. 본 논문은 이에 대한 직관적인 원인을 고찰하고, 이를 극복하기 위해, 기존의 FA에 부분 돌연변이 휴리스틱을 적용하여 개선된 FA(Improved FA)를 제안한다. 벤치마크 함수들을 최적화 하는 비교 실험 결과, 개선된 FA가 PSO와 기존의 FA보다 정확도와 수렴속도 측면에서 우수함을 보이고자 한다.

• Nutrition Research and Practice
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• 제3권2호
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• pp.122-127
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• 2009

Folate is generally considered as a safe water-soluble vitamin for supplementation. However, we do not have enough information to confirm the potential effects and safety of folate supplementation and the interaction with vitamin $B_{12}$ deficiency. It has been hypothesized that a greater methyl group supply could lead to compensation for vitamin $B_{12}$ deficiency. On this basis, the present study was conducted to examine the effects of high-dose folic acid (FA) supplementation on biomarkers involved in the methionine cycle in vitamin $B_{12}$-deficient rats. Sprague-Dawley rats were fed diets containing either 0 or $100{\mu}g$ (daily dietary requirement) vitamin $B_{12}/kg$ diet with either 2 mg (daily dietary requirement) or 100 mg FA/kg diet for six weeks. Vitamin $B_{12}$-deficiency resulted in increased plasma homocysteine (p<0.01), which was normalized by dietary supplementation of high-dose FA (p<0.01). However, FA supplementation and vitamin $B_{12}$ deficiency did not alter hepatic and brain S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH) concentrations and hepatic DNA methylation. These results indicated that supplementation of high-dose FA improved homocysteinemia in vitamin $B_{12}$-deficiency but did not change SAM and SAH, the main biomarkers of methylating reaction.

• 한국산업융합학회 논문집
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• 제16권1호
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• pp.1-8
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• 2013

In case that W/B is 20%, 30%, 40% respectively, the effects of additive and shrinkage reducing agent on the autogenous shrinkage for high strengthen concrete through the substitution of FA and SF analysis were obtained as following conclusions. When the ratio of FA increased, the compressive strength of high strengthen concrete is decreased in the early times. As the ratio of SF increase, the compressive strength also increased. Comparing with PC(Portland Cement) for 7 days curing, the strength is 13.8% of FA10 + SR0.5 and 19.2% of FA15 + SR0.5 decreased when W/B is 20%, and 6.1% of SF7.5 + SR0.5, 4.8% of SF15 + SR0.5, the strength are increased. In case that W/B is 30%, 13.1% of FA10 + SR0.5 19.1% of FA15 + SR0.5 the strength is decreased and 4.1% of SF 7.5 + SR0.5, 7.2% of SF15 + SR0.5 the strength are increased. In case of W/B 40%, 4.3% of FA10 + SR0.5, and 8.7% of FA15 + SR0.5, the strength is decreased and 3.3% of SF7.5 + SR0.5, 6.3% SF15 + SR0.5 the strength is increased. When the ratio of SR is 0.5%, autogenous shrinkage strain of OPC concrete appeared $-417{\times}10-6$ in 56days curing, the shrinkage strain is decreased 23.7%. The reducing effects of autogenous shrinkage when the mineral and shrinkage agent are used are the same as ones when only shrinkage agent used.

• 한국세라믹학회지
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• 제45권6호
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• pp.336-344
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• 2008

Rheological properties of cement pastes containing blast furnace slag (BFS: 3,900, $7,910\;cm^2/g$) or fly ash powder (FA: 4,120, $8,100\;cm^2/g$) according to the ratio of water/binder (W/B) and the dosage of polycarboxylate type superplasticizer (PC) were investigated by a mini slump and a coaxial cylinder viscometer. In this experiment, the ratio of replacing OPC with BFS or FA was 30 wt%, the W/B was from 30 to 70 wt%. As a result, the fluidity of cement paste containing BFS or FA was improved with increasing W/B and the dosage of PC. BFS or FA replaced cement paste with W/B 70% and PC 0.3% showed the highest fluidity. The segregation range of cement paste was occurred below $10\;d/cm^2$ of the yield stress and below 50 cPs of the plastic viscosity by the coaxial cylinder viscometer. And also it was formed that the plastic viscosity and the yield stress of FA replaced cement paste were higher than them of BFS replaced cement paste.

• Nuclear Engineering and Technology
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• 제49권1호
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• pp.224-233
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• 2017

In Korea, attempts have been made to develop high strength concrete for the safety and design life improvement of nuclear power plants. In this study, the cracking potentials of nuclear power plant-high strength concretes (NPP-HSCs) containing industrial by-products with W/B 0.34 and W/B 0.28, which are being reviewed for their application in the construction of containment structures, were evaluated through autogenous shrinkage, unrestrained drying shrinkage, and restrained drying shrinkage experiments. The cracking potentials of the NPP-HSCs with W/B 0.34 and W/B 0.28 were in the order of 0.34FA25 > 0.34FA25BFS25 > 0.34BFS50 > 0.34BFS65SF5 and 0.28FA25SF5 >> 0.28BFS65SF5 > 0.28BFS45SF5 > 0.28 FA20BFS25SF5, respectively. The cracking potentials of the seven mix proportions excluding 0.28FA25SF5 were lower than that of the existing nuclear power plant concrete; thus, the durability of a nuclear power plant against shrinkage cracking could be improved by applying the seven mix proportions with low cracking potentials.

• 한국미생물·생명공학회지
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• 제19권6호
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• pp.553-560
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• 1991

Bacillus circulans로부터 mitomycin C처리에 의해 유발되는 Bacteriophage Sigma FA1을 서당밀도균배 원심법 (sucrose gradient centrifugation)에 의해 분리, 정제하였다. Sigma FA1의 감수성숙주에 대한 치사작용은 single-hit 방식이었다. 한편, 세포에 감여된 후 phage DNA는 천천히 분해되기 시작했으며, 본 연구의 결과는 Sigma FA1의 세포에 대한 치사작용이 기존의 것과는 다른 것임을 입증시켰으며, 이는 단 백질분해기능에서 유래되는 듯 했다.

• 대한기계학회논문집B
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• 제36권3호
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• pp.293-299
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• 2012

대형 선박의 추진용 디젤엔진에서 버려지는 배기가스의 열을 회수하기 위한 랭킨사이클이 적용된 발전시스템에 대하여 R245fa 및 water 의 작동유체들에 따른 열역학적 효율 특성을 분석하였다. 그 이론적인 계산 결과로, 고정된 질량유량의 R245fa 에 대하여 터빈입구의 압력이 증가할수록 사이클, 시스템, 및 전체적 효율이 증가하였고, 사이클에 의해 발생되는 순동력도 증가하는 특성을 보였다. 반면, water 의 경우에는 R245fa 에 비하여 더 낮은 질량유량 및 터빈입구 압력의 비율에서 최대의 시스템 효율을 보였다. 또한 water 에 대하여 최적화된 사이클의 순출력, 시스템 효율, 및 전체적 효율의 값들은 R245fa 의 경우보다 더 크게 나타났다.

• 대한토목학회논문집
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• 제26권4B호
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• pp.427-432
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• 2006

생물학적 질산화 과정에서 비이온성 용존 암모나아(FA) 농도와 온도가 아질산 이온($NO_2{^-}$) 축적에 미치는 영향을 연구하였다. 암모늄 산화와 아질산 축적조건을 파악하기 위하여 암모늄 이온($NH_4{^-}$) 농도와 온도를 탈리한 다양한 FA 농도 조건에서 질산화 실험을 실시하였다. 암모늄산화균과 아질산산화균의 활성화에너지를 산정한 결과, 암모늄산화균의 활성화에너지는 $20^{\circ}C$ 이하에서 81.7 KJ/mol, $20^{\circ}C$ 이상에서는 32.5 KJ/mol로 차이가 있었으나, 아질산산화균의 활성화에너지는 온도에 관계없이 35.5 KJ/mol로 나타났다. 특히, FA 농도와 온도에 따른 질산화 실험결과, FA 농도에 의한 질산화 저해 및 아질산이온 축적 효과는 극히 미미하였으며, 온도조건이 아질산 이온 축적에 큰 영향을 미치는 것으로 나타났다.

• 대한기계학회논문집B
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• 제36권6호
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• pp.593-600
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• 2012

대형 선박의 추진용 디젤엔진에서 버려지는 배기가스의 열을 회수하기 위한 랭킨사이클이 적용된 발전시스템에 대하여 R245fa 및 water의 작동유체에 따른 그 엑서지 특성을 분석하였다. 그 이론적인 계산 결과로, R245fa에 대하여 터빈입구의 압력이 증가할수록 엑서지 효율 및 시스템의 엑서지 효율이 증가하였고, 엑서지 파괴율은 주로 응축기 및 증발기에서 상대적으로 높게 나타났다. 그리고 질량유량의 증가에 따라 시스템의 엑서지 효율이 증가하는 특성을 보였다. Water의 경우에, 증발기에서의 엑서지 파괴율은 R245fa의 경우와 유사하게 나타났지만, 터빈입구의 압력 및 질량유량 비율의 변동에 대하여 열원에 대한 엑서지 손실률이 가장 큰 폭으로 변동하였다.