• Korean Journal of Soil Science and Fertilizer
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• v.34 no.2
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• pp.122-128
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• 2001

In order to find out the effect of nitrogen fertilizers on soil pH, EC, $NO_3-N$ and lettuce growth, this study was conducted by pot experiment in plastic film house condition. The square-pot which was $42{\times}54.5{\times}22cm$ in length, width and height, respectively, was filled with two kinds of soils in different soil EC as $0.20dS\;m^{-1}$ and $1.13dS\;m^{-1}$. Seven kinds of nitrogen fertilizers (urea, potassium nitrate, calcium nitrate, ammonium nitrate, ammonium sulphate, complex fertilizer A(11-10-10) and complex fertilizer B(12-12-12)) were treated in same standard rate of nitrogen for lettuce, transplanted the six lettuce seedlings of 10 days grown per pot, and have been grown for 38~44 days with three times harvesting. Soil pH was increased with the potassium and calcium nitrate treatments and decreased with ammonium nitrate, ammonium sulphate, complex fertilzer A and B, and the pH of urea treatments was kept the same value as the pH of before experiment. The growing status of lettuce seedling were surveyed during the early period after transplanting and withering of seedling was occured in all treatments. The withering rates were 10% in soil of EC $0.20dS\;m^{-1}$ and 44% and 42% in complex fertilizer and ammonium sulphate treaments, respectively, in soil of EC $1.13dS\;m^{-1}$. $NO{_3}^-$ contents of lettuce were about $1,000{\sim}2,000mg\;kg^{-1}$ based on fresh weight and these contents were considered to be lower to compare the $NO{_3}^-$ level of EU countries.

• Journal of Animal Science and Technology
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• v.49 no.3
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• pp.329-340
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• 2007

This study was conducted to evaluate effects of fermented wild-ginseng culture by-product on growth performance, blood characteristics, meat quality and ginsenoside concentration of meat in finishing pigs. Forty-eight pigs(Landrace×Yorkshire×Duroc, 76.26±1.06kg average initial body weight) were used in 49d growth assay. Dietary treatments were included 1) CON(basal diet), 2) FWG1(basal diet+2.5% fermented wild-ginseng cultures by-product) and 3) FWG2(basal diet+5.0% fermented wild-ginseng cultures by-product). The pigs were allotted into four pigs per pen with four replicate pens per treatment by completely randomized design. No differences were found among treatments for ADG, ADFI and gain/feed from 0day to 49day of the experiment(P>0.05). Dry matter digestibility was greater in FWG1 treatment than CON treatment(P<0.05). In cholesterol concentration of blood, HDL cholesterol was significantly higher in CON treatment than FWG1 treatment(P<0.05). In meat quality, TBARS was significantly lower in FWG1 and FWG2 treatments than CON treatment(P<0.05). In sensory evaluation, Marbling was significantly higher in CON treatment than FWG1 treatment(P<0.05). Firmness in FWG2 and CON treatments was higher than FWG1 treatment(P<0.05). In meat color, L*-value of longissmus dorsi muscle was increased in FWG1 treatment compared to CON and FWG2 treatments(P<0.05). a* and b*-value of longissmus dorsi muscle were increased in CON and FWG1 treatments compared to FWG2 treatment (P<0.05). Ginsenoside concentration of meat was significantly higher in FWG2 treatment than CON treatment(P<0.05). In conclusion, fermented wild-ginseng culture by-product was effective for improving dry matter, TBARS, firmness, meat color and ginsenoside concentration of meat in finishing pigs.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.104-104
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• 2001

Ras는 세포의 성장과 분화 등 여러 필수적인 세포기능에 없어서는 안될 중요한 역할을 담당하며 Ras가 mutation되면 암 등의 치명적인 결과를 초래한다. Ras 발현은 유방암에서 tumor aggressiveness의 지표로 간주되고 있으며 유방세포의 침습성과 연관이 있다고 알려져 있으므로 ras가 전이과정에 미치는 영향에 관한 연구는 중요한 의미를 갖는다. 본 연구의 선행연구결과, H-ras와 N-ras 모두 transformed phenotype을 나타내지만 H-ras 만이 암전이에 있어서 중요한 침윤성을 유도하는 것을 밝혔다. 이 결과는 MCF10A 세포에서 H-ras와 N-ras에 의한 신호전달경로가 각각 다른 생물학적 전이활성을 나타냄을 시사한다. 세포의 이동성은 침습성에 있어서 결정적인 역할을 하므로, 본 연구에서 H-ras와 N-ras로 형질전환된 MCF10A세포에서 이동성을 시험한 결과, 세포의 이동성이 N-ras가 아닌 H-ras MCF10A 세포에서만 크게 증가된다는 것을 보았다. 이는 침습성을 나타내는 H-ras가 세포의 이동성을 증가시키는데 작용한다는 것을 말한다. H-ras에 의해 유도된 침습성과 이동성에 대한 분자적 기전에 관하여 연구하기 위하여 H-ras MCF10A와 N-ras MCF10A 세포에서 Ras의 downstream effector들, 특히 mitogen-activated protein kinases(MAPKinases)들인 JNK1, ERK, p38의 활성화를 살펴본 결과 p38 MAPKinase가 H-ras MCF10A 세포에서 현저하게 활성화됨을 보았다. p38 MAPKinase 저해제인 SB203580를 처리하던지 dominant negative p38 (DN p38) transfectant로 p38을 불활성화시켰을 때 세포침습성 및 이동성이 저해되는 결과를 얻었다. SB203580 처리한 H-ras MCF10A 세포에서 전이에 관여하는 효소인 MMP-2 분비가 감소되었다. H-ras에 의해 유도된 침습성과 이동성은 DN JNK1 transfectant에서는 변화가 없었으나 DN MEK transfectants에서는 유의성있게 감소되었다. 이상의 결과를 종합하면, MCF10A 세포의 침윤성과 이동성에는 p38 MAPKinase 활성이 중심적인 역할을 하며, JNK 활성은 영향을 미치지 않고, ERK-1/2 활성은 충분하지는 않으나 필요하다는 것을 알 수 있었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.6
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• pp.2879-2887
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• 2011

This research is aimed for the better understanding of corrosion behavior of carbon steel in ETA or $NH_3$ solution at high temperature. To minimize the corrosion it is important to select proper pH control agent(s), which also let it maintain basic or reductive environment inside the steel pipe. This work will provide the practical guideline which can be applied to the nuclear power plant for developing the life extension method of carbon steel. Experiments were carried out by measuring the corrosion rate using the potentiodynamic polarization curve of carbon steel in ETA and NH3 at different temperatures. The corrosion rate was estimated by using the Tafel curve measured under various test conditions: i) $NH_3$ is less than ETA as a pH agent. ii) the corrosion was reduced at high pH, and iii) the corrosion was maximum in the temperature range of $150\sim200^{\circ}C$.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.1
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• pp.17-23
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• 1981

The effects of potassium chloride and potassium sulphate on the volatilization of ammonia from acidic clayloam and tidal sandy clay loam soils applied with urea under flooded conditions were studied in a laboratory experiment. Results obtained were as follows; 1. The application of potassium to the acidic soil promoted the volatilization of ammonia through increasing soil pH. 2. The application of potassium to urea treated on the tidal soil which lead pH over 8.0 under flooded reduced conditions decreased the wet soil pH and reduced the volatilization of ammonia from the soil. These effects of potassium were more pronounced in the potassium sulphate treatment than in the potassium chloride. 3. More ammonia was volatilized from the acidic soil applied with potassium sulphate, however, the effects of potassium fertilizers applied to the high pH tidal soil seemed to be masked by high salt content of the soil. 4. Urea brought up soil pH significantly. Potassium sulphate was more effective than potassium chloride in raising pH of the acidic soil, though the reverse could be true in the tidal soil with high pH. The reduction of sulphate might be a major cause for the pH change.

• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.325-334
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• 2004

Two experiments were conducted to investigate the effects of Animunin Powder${\circledR}$ supplementation on the growth perfonnance and blood components in nursery and growing pigs. In Exp. 1, ninety six pigs(initial mean live weights 27,6 ${\pm}$ 2.63kg) were randomly allocated into four treatments with six replications per each treatment. Four treatments were control(CON), control + 0.1% Antibiotics(AB), control + 0.1% Animunin Powder${\circledR}$(AM), and control + 0.1% Antibiotics + 0.1% Animunin Powder${\circledR}$(ABM). During 4 weeks experiment, ADG of pigs was significantly(p < 0.05) higher in ABM treatment compared with CON and AB treatments, Serum IgG concentration was higher(P < 0.05) in AM and ABM treatments than CON. Serum from treated pigs ABM had higher(P < 0.05) albumin concentration in comparison to CON and AB treatments. In addition, higher (p < 0.05) serum lymphocyte concentration was found in ABM treatment compared with CON and AM treatments. Digestibility of dry matter was higher(P < 0.05) in ABM treatment compared with AB and AM treatments. However, no statistical differences(P > 0.05) were found in total protein content of serum and crude protein digestibility of diets. In Exp. 2, seventy five pigs(initial mean live weights 40.22 ${\pm}$ 2.82kg) were randomly allocated into three treatments with 5 replicates per each treatment for 29 days. Three treatments were control(CON), control + 0.1% Animunin Powder${\circledR}$(AM1) and control + 0.2% Animunin Powder${\circledR}$(AM2). During the whole experiment, pigs fed AM1 and AM2 diets were shown higher ADG than pigs fed CON diet. The ADFI of AM1 diet is higher(P < 0.05) compared to that of CON diet. Serum IgG and albumin concentration of AM1 and AM2 treatments were greater than those of CON treatment(p < 0.05). Lymphocyte was highest for AM1 and lowest for CON, with intermediate for AM2(P < 0.05). In conclusion, Animunin Powder${\circledR}$ was effective for improving growth performance and to increase the concentrations of blood IgG, albumin, total protein and lymphocyte in nursery and growing pigs.

• Korean Journal of Poultry Science
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• v.35 no.2
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• pp.131-136
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• 2008

This study was conducted to investigate the effects of dietary conjugated linoleic acid (CLA) and oil containing unsaturated fatty acid supplementation on egg production and quality in laying hens. Two hundred-eighty eight, 36 week old ISA brown commercial layer, were employed in a 5 week feeding trial. Dietary treatments are 1) BO (basal diet + 1% soybean oil + 1% oat), 2) BS (basal diet + 1% safflower oil + 1% oat), 3) BF (basal diet + 1% free fatty acid + 1% oat), 4) CD (basal diet + 1% CLA containing diglyceride + 1% oat), 5) CT (basal diet + 1% CLA containing triglyceride + 1% oat) and 6) CP (basal diet + 1% CLA by-product + 1% soybean oil). For overall period, hen-day egg production was not significant among treatments (P>0.05). Egg shell breaking strength at 3 weeks in CP treatment was significantly lower than BS, BF, CD and CT treatments (P<0.05) and that at 4 weeks in BO and CP treatments was significantly lower than others (P<0.05). Egg shell thickness at 3 and 4 weeks in CP treatment was significantly lower than BS, BF, CD and CT treatments (P<0.05). Egg weight at 3 and 4 weeks in CP treatment was significantly lower than others (P<0.05). Yolk height at 4 weeks in BF and CT treatments was significantly highest compared to BO, CD and CP treatments (P<0.05) and among BO, CD and CP treatments, that in BO and CD treatments was significantly higher than CP treatment (P<0.05). At 4 weeks, yolk color in CP treatment was significantly higher than BO and BS treatments (P<0.05). Haugh unit at 3 and 4 weeks in BO and CP treatments was significantly lower than others (P<0.05). In conclusion, supplementing CLA and oil containing unsaturated fatty acid for laying hens improved egg shell breaking strength, egg shell thickness, egg weight, yolk height, yolk color and haugh unit.

• Plant Journal
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• v.17 no.4
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• pp.35-40
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• 2021

In this study, a technical characteristic test was conducted on the gas turbine generator system of Seoincheon Combined cycle no.6 to derive and verify the model constants. As a result of the generator maximum/minimum reactive power limit test, the maximum reactive power limit is 80 MVar and the minimum is -30 MVar. The generator uses the GENROU model, the field time constant (T'do) is 4.077 s, and the inertial constant (H) is 5.461 P.U. Excitation system used ESST4B model to derive and verify model constants by simulating no-load 2% AVR step test, PSS modeling derived from PSS2A model constants, and simulated and compared measurement data measured when PSS off/on Did. The GGOV1 model was used for the governor-turbine, and the numerical stability of the determined governor-turbine model constant was verified by simulating a 10% governor step test through the PSS/E simulation program

• Food Science and Preservation
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• v.16 no.5
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• pp.759-764
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• 2009

The antimicrobial activities of extracts of Prunus mume by sugar against food poisoning bacteria, and the effects of heat and pH treatment on these antimicrobial activities, were investigated. The level of total solids, pH, and acidity of P. mume extracts were 55.08% (w/w), pH 3.1, and 1.52%, respectively. P. mume extracts showed the strongest antimicrobial activity against Vibrio parahaemolyticus, among the bacteria tested. P. mume extracts significantly inhibited the growth of V. parahaemolyticus, Bacillus cereus, and Staphylococcus aureus at levels of 1-2% (w/v) of extracts in media. The antimicrobial activities of P. mume extracts were neither affected by heating at $65-125^{\circ}C$ for 30 minutes, nor by neutralization of extract to pH 7.0.

• Geotechnical Engineering
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• v.11 no.3
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• pp.5-16
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• 1995

In this paper, two leaching tests(batch test & column test) were carried out to estimate the detrimental effects of coal ash leachates. The variation of constituents and concentration of coal ash leachate with the lapse of leachins time was analysed through the column tests. From the test results, it was found coal tach can be classified as a general waste, and all other items except pH of coal ash leachate are satisfied the concentration requirements for the drinking water. It was also found the concentration of coal ash rapidly decrease with the lapse of the leaching time and become the insignificant value after an elapsed time.