• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.129-133
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• 1995

Continuous fermentations were performed in order to investigate the effect of culture condition on the yeast RNA accumulation and autolysis efficiency. The content of intracellular RNA increased with increasing dilution rate, showing its maximum value of 14.8% at D=0.35 $h^{-1}$. Also, both RNA productivity and specific RNA productivity tended to increase with the increase of dilution rate. The maximum biomass was obtained at $30^{\circ}C$ in the fixed dilution rate of 0.2 $h^{-1}$, whereas the maximum RNA content appeared at the lowest temperature experimented. Growth rate affected significantly on the yeast autolysis efficiency such that the extraction ratio(TN/TN) increased with increasing growth rate, whereas the hydrolysis ratio(AN/TN) was reversed. On the other hand, its efficiency was little affected by cultivation temperature.

• Korean Journal of Environmental Agriculture
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• v.11 no.1
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• pp.77-85
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• 1992

Of the cadmium-tolerant 162 bacterial strains isolated from soils, river waters or active sludges of waste-water disposal plants in the Gyeongnam province a strain C1, which showed considerably higher growth rate in the agar plate containing 2000 ppm than any other strains isolated, was identified as a Pseudomonas putida or its similar strain when analyzed by taxonomical characteristics. Optimum pH and temperature for the growth of the P, putida were 7.0 and $30^{\circ}C$, respectively. This strain was resistant to antibiotics(ampicillin, chloramphenicol and streptomycin), and heavy metals(lithium, cupper, lead and zinc). This strain utilized salicylate, naphthalene or xylene as a sole carbon source. The rate of cadmium accumulation in P. putida cell was enhanced at low concentration of Cd in the growth media. The maximum cadmium absorption by this strain grown in 1 and l0ppm of Cd was respectively 78% and 60% 24 hrs after culture, but in 100 ppm Cd, 40% 48 hrs after culture. Addition of a non-ionic surfactant Triton X-100(0.1%) to the medium enhanced the accumulation of cadmium in the P. putida up to approximately 37%.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.1
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• pp.24-31
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• 2007

Global fates of polychlorinated biphenyl(PCB) were investigated with a fugacity based multimedia transport and fate model, Globe-POP(persistent organic pollutant). The accumulation of PCB was directly affected by the emission patterns of PCB into the atmosphere and surface areas of environmental compartments. Partition coefficients and reaction rates also influenced on the accumulation patterns of PCB. The emission patterns of PCB in 10 climate zones were consistent for the past 70 years, while the contribution of PCB in high-latitude zones to the globe has increased by cold condensation. Considering the amounts of emission and accumulation of PCB, the North temperature zone is regarded as an important source and sink of PCB. Meanwhile, in spite of no significant sources, POPs accumulate in Antarctic environments mainly due to extremely low temperature. Finally we suggested that a global water balance accounting for snow/ice should be incorporated into multimedia environmental models for high-latitude zones and polar regions with the seasonal snow pack and/or permanent ice caps. The modified model will be useful to evaluate the influence of climate change on the fate of POPs.

• Journal of the Korea Society of Computer and Information
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• v.27 no.10
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• pp.123-130
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• 2022

In this paper is one of the measures to prevent concrete collapse accidents at construction sites in advance. Analyzed based on accumulated Meteorological Agency data. It is a reliable model that confirms the prediction of the decrease rate occurrence interval, and the verification items such as p_value is 0.5 or less and ecof appears in one direction through the SARIMA model, which is suitable for regular and clear time series data models, ensure reliability. Significant results were obtained. As a result of analyzing the temperature change by time zone and the water reduce ratio by section using the data secured based on such trust, the water reduce ratio is the highest in the 29-31 ℃ section from 12:00 to 13:00 from July to August. found to show. If a factor in the research result interval occurs using the research results, it is expected that the batch plant will produce Ready-mixed concrete that reflects the water reduce ratio at the time of designing the water-cement mixture, and prevent the decrease in concrete compressive strength due to the water reduce ratio.

• Analytical Science and Technology
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• v.24 no.6
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• pp.484-492
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• 2011

Bioaccumulation status and distribution characteristics of PCDDs, PCDFs and DL-PCBs in cruian carp collected from the four representative sites of major river systems in Korea were investigated. The recovery rates of PCDDs and PCDFs ranged from 50.6% to 88.3%, and those of DL-PCBs ranged from 52.3% to 93.2%. The mean, median and concentration range of ${\sum}$dioxins, which represents the total concentratons of PCDDs, PCDFs and DL-PCBs accumulated in the muscle of crucian carp, were 0.39, 0.14 and 0.047-1.0 pg TEQ/g wet wt., respectively. DL-PCBs were detected above the detection limit from all the samples, whereas PCDDs and PCDFs were detected from limited crucian samples. The relative contribution of DL-PCBs to ${\sum}$dioxins was remarkably larger than those for PCDDs and PCDFs. The percent contribution was 83.6% for DL-PCBs, and followed by 12.7% and 3.7% for PCDFs and PCDDs, respectively.

• Proceedings of the KAIS Fall Conference
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• 2000.10a
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• pp.259-261
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• 2000

본 연구는 사료내 인분해효소 phytase을 첨가하여 곡류내 유기태인의 이용성을 최대화하고 인의 배설량을 최소화하므로서 저공해성 산란계 사료 개발에 기초자료로서 활용하는데 목적이 있다. 부화 후 64주령된 갈색 하이라인 24수(평균체중 1.9kg, 산란율 78.4%)를 공시하였다. 대조구는 옥수수-대두박 위주로 배합된 사료, 처리구는 대조구 사료에 각각 phytase를 200 unit/kg, 400 unit/kg 그리고 600 unit/kg 첨가한 구로서 4처리 3반복, 반복당 2수씩 완전임의 배치하였다. 건물과 질소 이용률을 보면 처리간의 차이는 보이지 않았다(P>0.05). 광물질 중 회분과 칼슘의 경우 phytase를 200 unit을 첨가한 구에서 가장 높은 이용률을 보였다(P<0.05). 인의 이용률은 phytase를 600 unit 첨가한 구가 57.64%로 다른 처리구보다 이용률이 높은 것으로 나타났다(P<0.05). 칼슘의 섭취량과 배설량을 고려한 결과 칼슘의 축적량은 phytase를 200 unit와 400 unit 첨가한 구가 대조구와 phytase를 600 unit 첨가한 구보다 높았다(P<0.05). 산란계에 대한 각각의 인의 섭취량을 보면 phytase를 600 unit 첨가한 구가 대조구, 200 unit 첨가한 구, 400 unit 첨가한 구보다 많은 양을 섭취하였으나(P<0.05), 인의 배설량에는 별다른 차이가 없었다(P>0.05). 그로 인해 인의 축적량 또한 phytase를 600 unit 첨가한 구가 다른 처리구에 비해 많이 축적되었다(P<0.05). 혈중 칼슘의 함량은 phytase를 400 unit 첨가한 구와 600 unit 첨가한 구, 대조구간에는 서로 유의적인 차이가 없었고, phytase를 200 unit 첨가한 구보다 그 함량이 높게 나타났다(P<0.05). 결론적으로 산란계 사료에 phytase를 첨가할 때 환경문제를 야기시킬 수 있는 인의 배설량을 감소시키고 값비싼 무기태 인의 일부를 대체하는데 크게 기여할 수 있으리라 사료된다.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.423-423
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• 2010

유기발광소자의 제작 기술이 빠르게 발전함에 따라 디스플레이와 조명 분야에서 많은 응용 가능성을 보여주고 있다. 유기발광소자의 발광효율은 발광층내에서 전자와 정공의 비와 밀접한 관계가 있기 때문에 전자 수송층과 정공 수송층내에서 전하의 이동도를 제어하는 구조에 대한 연구는 매우 중요하다. 본 연구에서는 전자 수송층으로 tris(8-hydroxyquinoline)aluminum ($Alq_3$)와 4,7-diphenyl-1,10-phenanthroline (BPhen)의 다중 이종구조를 사용하여 제작된 녹색 유기발광소자의 전기적 성질과 광학적 성질을 연구하였다. $Alq_3$와 BPhen 다중 이종구조의 위치와 이종구조 개수의 변화에 따라 전자의 변하는 전송특성으로 인하여 변화되는 발광특성을 체계적으로 조사하였다. 유기발광소자의 구동전압은 $Alq_3$/BPhen 이종구조의 수가 증가할수록 증가하는 경향을 보인다. $Alq_3$와 BPhen 내에서 전자의 이동도가 다르기 때문에 $Alq_3$/BPhen 이종계면에 전자가 축적되어 공간전하를 형성하므로 계면에서 내부전계가 형성되어 구동전압이 약간 증가하는 경향을 보인다. 또한 $Alq_3$/BPhen 이종계면에서 축적된 전자들로 인하여 형성된 내부 전계로 인해 저전압에서 누설 정공의 수가 증가하였다. 그러나 다중 이종구조로 된 전자 수송층을 포함한 유기발광소자의 발광 효율은 구동전압이 증가할수록 안정화 되었다. 이는 이종계면의 수가 증가함에 따라 각각의 이종계면에서 축적되는 전자의 양이 감소하기 때문에 고전압에서 효율감소율이 작아졌다. $Alq_3$/BPhen 다중 이종구조를 가진 전자 수송층내에서 전자의 전송 메카니즘에 대한 이해는 유기발광소자의 발광효율이 안정화된 구조를 설계하는데 중요한 실험적 결과를 제공한다.

• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.96-101
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• 1998

Respiratory denitrification experiments were performed using different carbon sources (acetic acid, glucose, methanol, molasses). In the culture media with glucose and molasses, COD consumption and denitrification rates were higher than with acetic acid and methanol. However, up to 30-40% of reduced nitrate and nitrite were converted to ammonium in glucose and molasses media. In the culture media with acetic acid and methanol, ammonium was not accumulated. Some of the consumed COD seemed to be used by the acid formers for the acidification in glucose and molasses media. By initial pH control of with molasses media, higher denitrification rate (up to 99%) and faster response could be obtained.

• The Southeast Asian review
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• v.24 no.2
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• pp.1-33
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• 2014

아세안은 한중일과의 무역을 통한 경제적 연계의 심화현상과 최근 글로벌 위기로 인한 경기침체를 고려하여 새로운 경제성장추진을 위해 동북아의 한중일 삼국과의 무역자유화를 적극 추진하고 있다. 이미 ASEAN-중국, ASEAN-일본, ASEAN-한국 양자간 자유무역협정(FTA)이 발효되어 실행되고 있으며, 이들 3개 양자협정을 아우르는 A+3FTA(ASEAN+중국+일본+한국) 논의도 진행중이다. 이에 본 연구는 이들 4개 자유무역협정의 경제적 효과를 분석하여 과연 A+3FTA가 아세안은 물론 동아시아 역내에서 보다 바람직한 통상정책인지를 평가한다. 본 논문의 정성적 평가는 기존의 경제통합의 경제적 효과를 결정하는 이론에 근거하여 참여국의 제반 경제적 현황(경제규모, 소득수준, 경제개발수준, 거래비용, 무역 및 산업구조, 관세율 등)을 통계적으로 비교 분석한다. 한편 정량적 평가는 무역의 경제적 파급효과 분석에 널리 이용되고 있는 연산가능한 일반균형모형(CGE)분석방법을 적용한다. 정태적 효과의 분석을 위해서 GTAP 모형을 이용하며, 이와 더불어 동태적으로 투자를 통한 자본축적을 반영하는 자본축적 CGE 모형분석을 병행한다. 분석결과 후생 및 생산확대 측면에서 아세안의 경우 일본과의 양자간 FTA가 한국이나 중국과의 FTA에 비해 보다 긍정적인 후생증진을 가져올 것으로 기대되며, 아세안과 한중일 모두에게 A+3FTA가 동아시아 역내에서 보다 바람직한 자유무역협정이 될 것으로 평가된다.

• The Korean Journal of Food And Nutrition
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• v.28 no.4
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• pp.650-657
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• 2015

This study aimed to investigate the suppressive effect of acorn extracts, by evaluating 70% ethanol extract (AE) and hot water extract (AW) using 3T3-L1 preadipocytes. We applied various levels (0, 100, 200, 300 and $500 {\mu}g/mL$) of AE and AW to 3T3-L1 preadipocytes. The cell viability of the 3T3-L1 preadipocytes was not affected by up $300 {\mu}g/mL$ of extracts, but was suppressed by level $500{\mu}g/mL$ of both AE and AW by 20% and 9% respectively. The accumulation of lipid droplets in differentiated 3T3-L1 preadipocytes was dose-dependently suppressed by AE and AW. Especially, at high concentrations ($300{\mu}g/mL$), AE (42%) was more effective than AW (41%). Reactive oxygen species (ROS) was also dose-dependently suppressed by treatment with AE (58%) and AW (52%). With regard to the mRNA related to differentiated 3T3-L1 preadipocytes, $PPAR-{\gamma}$ and aP2 were suppressed by treatment with AE (54 and 40%) and AW (38 and 18%). From our results, acorn extract (AE) has more suppressive effects than AW in differentiated 3T3-L1 preadipocytes. We therefore concluded that acorn has suppressive effects against obesity in differentiated 3T3-L1 cells due to antioxidation.