• Magazine of the Korean Society of Agricultural Engineers
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• v.43 no.5
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• pp.153-162
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• 2001

A study was carried out to investigate the water balance and losses of nutrients at a paddy plot located at the southern Korea. The observed amount of precipitation, irrigation, runoff, evapotranspiration and percolation for the experimental paddy plot during cropping period were 1,030, 566, 701, 551. and 310 mm for 1999 and 1.214, 413, 710, 682, and 234 mm for 2000 year, respectively. The measured input quantities of N and P into the paddy field during cropping period were 122 to 140 kg N $ha^-1$ and 29 to 30 kg $P_2O_5$ kg $ha^-1$ by chemical fertilizer, 20 to 28 kg N $ha^-1$ and 0.35 to 0.36 kg P $ha^-1$ by precipitation, and 26 to 35 kg N $ha^-1$ and 0.57 to 0.72 kg P$ha^-1$ by irrigation water. respectively. The output amounts of N and P from paddy field were measured as follows. They were 48 to 52 kg N $ha^-1$ and 1.1 to 1.6 kg P $ha^-1$by runoff water, and 9 to 12 kg N $ha^-1$ and 0.04 to 0.05 kg $ha^-1$ by percolation water. When the runoff losses of nutrients were compared to applied chemical fertilizer. it was found that 34.3 % to 42.6 % of nitrogen lost via runoff while runoff losses of phosphorus account for 3.8 % to 5.3 % of the total applied amount. When the ratio was calculated between nutrients losses by percolation water and the applied of chemical fertilizer, two year results showed 6.4 % to 9.8 % for the nitrogen and 0.1% to 0.2% phosphorus, respectively.

• Korean Journal of Materials Research
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• v.21 no.12
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• pp.690-696
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• 2011

In this study, nano-sized tin oxide powder with an average particle size of below 50 nm is prepared by the spray pyrolysis process. The influence of air pressure on the properties of the generated powder is examined. Along with the rise of air pressure from $0.1kg/cm^2$ to $3kg/cm^2$, the average size of the droplet-shaped particles decreases, while the particle size distribution becomes more regular. When the air pressure increases from $0.1kg/cm^2$ to $1kg/cm^2$, the average size of the dropletshaped particles, which is around 30-50 nm, shows hardly any change. When the air pressure increases up to $3kg/cm^2$, the average size of the droplet-shaped particles decreases to 30 nm. For the independent generated particles, when the air pressure is at $0.1kg/cm^2$, the average particle size is approximately 100 nm; when the air pressure increases up to $0.5kg/m^2$, the average particle size becomes more than 100 nm, and the surface structure becomes more compact; when the air pressure increases up to $1kg/cm^2$, the surface structure is almost the same as in the case of $0.5kg/cm^2$, and the average particle size is around 80- 100 nm; when the air pressure increases up to $3kg/cm^2$, the surface structure becomes incompact compared to the cases of other air pressures, and the average particle size is around 80-100 nm. Along with the rise of air pressure from $0.1kg/cm^2$ to $0.5kg/cm^2$, the XRD peak intensity slightly decreases, and the specific surface area increases. When the air pressure increases up to $1kg/cm^2$ and $3kg/cm^2$, the XRD peak intensity increases, while the specific surface area also increases.

• KSBB Journal
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• v.14 no.1
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• pp.119-123
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• 1999

A jet-loop reactor was used for the biological treatment of ethylene glycol(EG) which is a main component of polyester weight-loss wastewater, and is difficult to be removed by physicochemical treatments. Volumetric oxygen coefficient(kLa) of jet-loop reactor was significantly larfgeer that of air-lift reactor. When organic loading rates of synthetic polyester weight-loss wastewater were 2.64 $kgOD_{Mn}/m^3$.day and 3.07 $kgCOD_{Cr}/m^3$.day, the effluent concentrations were measured as 154 $mgCOD_{Mn}/L$ and 156$mgCOD_{Cr}/L$, and removal efficiencies were found as 93%and 93.6%, respectively. The specific removal rate was proportionally increased from 0.25 to 1.60 $kgCOD_{Mn}$-removed/kgMLVSS.day as specific loading rate was increased from 0.25 to 1.72 $kgCOD_{Mn}$/kgMLVSS.day. Also, kinetics constants such as $K_s$, k, $K_d$, and Y were estimated as 89 mg/L, $0.05 hr^{-1}$, 0.1$day^{-1}$ and 0.78 respectively. When the organic loading rates of real polyester weight-loss wastewater were 2.64 $kgOD_{Mn}/m^3$. and 5.24 $kgCOD_{Cr}/m^3$. day, the effluent concentrations were measured as 150 $mgCOD_{Mn}$/L, and 306 $mgCOD_{Cr}$/L, and removal efficiencies were found as 93.2% and 93%, respectively. This study demonstrated that EG in the wastewater could be efficiently removed biologically using a jet-loop reactor.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.3
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• pp.180-186
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• 1984

From June, 1980 to October, 1982, this study was carried out to find an optimal grazing system on the timothy and orchardgrass-dominated pasture. Five different systems consisted of set stocking, modified set stocking, rotational grazing, 'wye college' system and zero grazing have been applied. The results obtained were as follow: 1. Herbage DM yield per ha with 'wye college' system, set stocking, modified set stocking, rotational grazing and zero grazing were 6936.7 kg,6794.3 kg, 6686.9 kg 6675.7 kg and 5083.4 kg respectively. Among treatments were not different in DM yield. 2. In herbage utilization, zero grazing was the highest than other. Zero Grazing, Rotational grazing, 'Wye college' system, Modified set stocking and set stocking was 89.3%, 70.8%, 64.4% and 46.1% respectively. 3. Daily intake per head with 'wye college' system was the highest than others and zero grazing was the lowest than others. 4. Daily gain with 'wye college' system, rotational grazing, modified set stocking, set stocking and zero grazing were 0.60kg, 0.55kg, 0.50kg, 0.43kg and 0.42 respectively. Among treatment, there was no significance. 5. Total weight gain per ha with 'wye college' system, rotational grazing, modified set stocking, zero grazing and set stocking were 339.5kg, 299.1kg, 253.3kg, 226.6kg and 222.2kg respectively. 6. Grazing time among treatments was not significant. 'Wye college' system spent the shortest time, 367.3 minutes and set stocking consumed the longest time, 422.1 minutes. 7. Daily grazing time by seasonal change with June, July, August, September and October was 304.9 min., 359.4 min., 437.9 min., 483.3 min. and 395.8 min., respectively. According to passing the season, grazing time was lengthened. 8. Grazing time for Korean native cow, native cow charolais and native cow holstein were not significant. Native sow charolais consumed the longest time, 457.0 min., whereas Korean native cow consumed the shortest time, 422.4 min..

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.2
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• pp.53-63
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• 1994

In order to investigate the effects of application rates of mineral N and cattle slurry on the dry matter yield of Reed canarygrass grown in different cutting frequency, was was cernpared for the efficiency of N utilization. Annual rates of mineral N and cattle slurry N of 0 (control), 90kg, 180kg, 270kg and 360kg/ha in 3 cuttings, 0, 120kg, 240kg, 360kg and 480kg/ha in 4 cuttings, and 0, 150kg, 300kg, 450kg and 600kg/ha were applied as urea and cattle slurry in 5 cuttings, respectively. The results were summarized as follows: 1. The annual dry matter yields were increased with application rates of mineral N and cattle slurry. The annual dry matter yields of mineral N obtained were 14.4 ton/ha(ranged from 10.46 ton to 16.91 ton/ha) in 3 cuttings, 13.88 ton/ha(ranged from 9.91 ton to 16.53 ton/ha) in 4 cuttings and 15.98 ton/ha(ranged from 12.0 ton to 18.25 ton/ha) in 5 cuttings. The annual dry matter yields of cattle slurry obtained were 12.14ton/ha(ranged from 8.92 ton to 11.79ton/ha) in 3 cuttings, 10.81ton/ha(ranged from 8.92 to 11.79 ton/ha) in 4 cuttings and 12.98ton/ha(ranged from 10.68 ton to 14.85ton/ha) in 5 cuttings. 2. Relative dry matter yield of cattle slurry as compared to mineral N were 84.3%, 77.9% and 81.2% in 3, 4 and 5 cuttings. 3. Average increase in dry matter production(kgDM/kgN) tended to decrease with application rates of mineral N and cattle slurry, and higher cutting frequencies. Average increase in dry matter production obtained were higher values at rates of 30kg/ha/cut in both of mineral N and cattle slurry. Average increase in dry matter production to mineral N were 23.9kg, 18.8kg and 15.2kgin 3, 4 and 5 cuttings, respectively. 4. Average increase in total nitrogen yield(kgTN/kgN) to mineral N obtained were 0.46kg at rates of 60kg/ha/cut in 3 cuttings, and 0.45kg and 0.40kg at rates of 30kg/ha/cut in 4 and 5 cuttings. 5. Average increase in dry matter production(kgDM/kgN) to cattle slurry obtained were 13.7kg and 19.5kg at rates of 30kg/ha/cut in 3 and 4 cuttings, and 9.7kg at rates of 60kg/ha/cut in 5 cuttings. 6. Average increase in total nitrogen yield(kgTN/kgN) to cattle slurry was not concern to the rates of application. Average increase in total nitrogen yield to cattle slurry obtained were 0.11kg, 0.20kg and 0.21kg in 3, 4 and 5 cuttings. 7. Relative average increase in dry matter production of cattle slurry as compared to mineral N were 33.1%, 52.1% and 50.0% in 3, 4 and 5 cuttings. Relative average increase in total nitrogen yield of cattle slurry as compared to mineral N were 28.9%, 51.3% and 55.3% in 3, 4 and 5 cuttings.

• Journal of Food Hygiene and Safety
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• v.8 no.3
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• pp.163-169
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• 1993

The acute toxicity of lAS-Na(Linear Alkylbenzene Sulfonate-Na) and MES (ASME, Alpha-Sulfo fatty acid Methyl Ester), surfactans, was eyaluated in ICR mice for 14 days. Mice aging 6 weeks were administered orally with 0, 1,000, 1,320, 1,780, 2,280, 3,000 mg/kg of lASNa or 0, 1,000, 1,560, 2,450, 3,830, 6,000 mg/kg of MES in saline. The body weight of the treated animals was not significantly different from the controls. The main clinical signs of animals treated with lAS-Na or MES were diarrhea, decreased motor acthity and piloerection. The congestion in small intestine was only gross finding in dead animals treated with two sulfactants. In this study, $LD_{50}$ values of lAS-Na and MES were eyaluated 1,319 mg/kg in male and 1,402 mg/kg in female mice, 2,040 mg/kg in male and 2,548 mg in female mice, respectiyely.

• The Korean Journal of Pesticide Science
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• v.13 no.3
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• pp.190-196
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• 2009

The residues of abamectin 1.8% EC, resisted for control of pine wood nematode, Bursaphelenchus xylophilus in pine tree were surveyed in tissue of Pinus thunbergii and P. koraiensis after injection of a liquid formulation. Limits of detection of abamectin in tissue of P. thunbergii were $0.05\;mg\;kg^{-1}$ and mean recoveries at $0.5\;mg\;kg^{-1}$ trunk injection were 90.9% and 93.1% respectively in stem and trunk of P. thunbergii. Abamectin 1.8% EC, trunk injected in 15 m height P. thunbergii were detected in all stem (edible part of carrier insect of pine wood nematode, Monochamus alternatus) from 0.29 to $0.73\;mg\;kg^{-1}$ after 150 days injection. Amount of residue of abamectin 1.8% EC in 12.6 cm mean breast height diameter (DBH) P. thunbergii were variable depending on individual trees in natural forest. Amount of residues in lower and middle part of trunk were reduced with the passage of the injection time. In upper part of trunk were detected $1.84\;mg\;kg^{-1}$ on 30 days after injection however $0.65\;mg\;kg^{-1}$ on 15 days after injection and under detection limit on 100 and 180 days after injection in P. thunbergii. Bottom and middle parts of crown were detected $0.183\;mg\;kg^{-1}$ and $0.173\;mg\;kg^{-1}$ respectively on 180 days after injection in P. thunbergii. Mean residues of abamectin in crown and trunk were $0.80\;mg\;kg^{-1}$ and $0.30\;mg\;kg^{-1}$ on 170 days after trunk injection in 20 cm DBH and 9 m height P. koraiensis. Mean residues of abamectin in crown and trunk were $0.67\;mg\;kg^{-1}$ and $0.36\;mg\;kg^{-1}$ on 170 days after trunk injection in 15 cm DBH and 6 m height P. koraiensis.

• Korean Journal of Environmental Agriculture
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• v.22 no.3
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• pp.227-232
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• 2003

This study was conducted to evaluate the terminal residue of a new fungicide, KNF 1002, in cucumber and pepper under greenhouse and field conditions. When a microemulsion formulation (20%) of KNF 1002 was applied once or twice during $1{\sim}7$ days before harvest, its terminal residue in cucumber ranged <$0.02{\sim}0.20\;mg/kg$ under greenhouse condition. In pepper, its figure recorded $0.31{\sim}0.79\;mg/kg$ and $0.11{\sim}0.28\;mg/kg$ under greenhouse and field conditions, respectively. Much higher level of terminal residues was observed in leaves than those in fruits in pepper, showing $7.38{\sim}25.20\;mg/kg$ and $0.11{\sim}1.99\;mg/kg$ under greenhouse and field conditions, respectively. Cultivation condition affected evidently the residue level in pepper harvests. Residual pattern of KNF 1002 seemed to be comparable to strobilurin fungicides currently used.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.563-569
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• 2013

This experiment was carried out to investigate the effect of liquid-pig-manure application method (Tr.1: surface appl. LPM 150%, Tr.2: surface appl. LPM 50% + LPM 50%, Tr.3: chemical fertilizer, Tr.4: soil injection LPM 150%, Tr.5: soil injection LPM 50% + surface appl. 50%, Tr.6: no fertilizer) and the economic efficiency of yield on forage crops cultivaion. In barley cultivation experiment, Tr.5 was found to be best, showing the yield of 1,462 kg $10a^{-1}$, and followed by Tr.2(1,226 kg $10a^{-1}$), Tr.3(1,226 kg $10a^{-1}$), Tr.4(1,225 kg $10a^{-1}$) and Tr.1(1,209 kg $10a^{-1}$) in order. In maize cultivation experiment, Tr.4 was found to be best, showing the yield of 2,142 kg/10a, and followed by Tr.1(2,125 kg $10a^{-1}$), Tr.3(2,024 kg $10a^{-1}$), Tr.5(2,011 kg $10a^{-1}$) and Tr.2(1,925 kg 1$10a^{-1}$) in order. The income was showing 1,274,000 ~ 1,591,000 Won $10a^{-1}$ in barley, whereas 766,000-794,000 Won 1$10a^{-1}$ in maize. There was more economical efficiency in barley cultivation than maize cultivation. Rather than the LPM surface application, LPM soil injection was more effective.

• The Korean Journal of Food And Nutrition
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• v.16 no.1
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• pp.54-59
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• 2003

This studies were performed to functional food consisted of herb mixture having an effect on postpartum body weight control in 105 subjects(control group n=54, experimental group n=51). Mean age of control and experimental group were 29.3 and 29.1 Mean pregravida body mass index of control and experimental group were 22.8 and 21.5. Total weight gain during the period of pregnancy of control and experimental group were 19.1kg and 17.8kg. In this studies, changes in postpartum weight was measured until one year after parturition. Until 1 month after parturition, there almost had no changes in weight all of two groups. But after 2 month, change in weight loss between two groups was shown definitely. Mean weight loss of control group and experimental group were 2.3kg and 6.5kg after 2 month, 3.7kg and 9.8kg after 3 month, 5.0kg and 10.4kg after 1 year(p<0.01).