• Korean Journal of Environmental Agriculture
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• v.22 no.1
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• pp.70-73
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• 2003

Nitrate contamination in the aquatic systems is the primary indicator of poor agricultural management. The influence of sewage sludge application rates (0, 10, 25, 50 and 100 dry Mg/ha) on distribution of nitrate originating from the sewage sludge in soil profiles was investigated. Soil profile monitoring of nitrate was carried out with a Lakeland clay soil in 1997. Irrespectively of the sewage sludge application rates up to 50 dry Mg/ha, the concentration of $NO_3$-N at the 120 cm depth was below 10 mg/kg and the difference due to the amount of sewage sludge application was negligible at this depth. There was virtually no $NO_3$-N below 120 cm depth and this was confirmed by a deep sampling up to 300 cm depth. Most of the nitrate remained in the surface 60 cm of the soil. Below 120 cm depth nitrate concentration was very low because of the denitrification even at high sewage sludge rate of 100 dry Mg/ha. The $NO_3$-N concentrations in the soil fluctuated over the growing season due to plant uptake and denitrification. The risk of groundwater contamination by nitrate from sewage sludge application up to high rate of 100 dry Mg/ha was very low in a wheat grown clay soil with high water table ( < 3 m).

• Korean Journal of Environmental Agriculture
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• v.25 no.2
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• pp.170-173
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• 2006

This study was conducted to analyze the effects of fowl manure application on growth and quality of Ficus benjamiana. The growth of F. benjamiana was the best at the application of 10% fowl manure. The nutrient uptake increased as the dates passed after transplanting. By the elements, the uptake amount was high in order of N>K>Ca>P>Mg. By fowl manure application rates, the nutrient uptake was the highest in 10%. The mot growth characteristics improved in higher fowl manure application rates, and it was the best in 10%.

• Korea Journal of Hospital Management
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• v.29 no.1
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• pp.56-63
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• 2024

Purposes: This study aims to analyze the correlation with the current status of the medical resident application rate, physician's income, and non-benefit rates of majors in each specialty subject and to suggest implications. Methodology: First, it analyzes the correlation between the medical resident application rate by specialty subject and the income of physicians. Second, it analyzes the correlation between the income of specialists and the non-benefit rate for each specialty subject at the clinic level. Findings: First, a significant positive correlation was found between the medical resident application rate and the average physician's income for each specialty subject (r=.718, p<.01). Second, a significant positive correlation was observed between physician income at the practitioner level by medical specialty and the non-benefit rate (r=.726, p<.01). Practical Implications: In this study, the correlation between medical resident application rate by specialty subject and physician's income, non-payment and physician's income was confirmed. Choosing a department that is less risky and can earn higher income is a natural phenomenon, but it is necessary to adjust the physicians crowding phenomenon to a specific specialty subject at the government level to maintain the medical system.

• Korean Management Science Review
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• v.16 no.1
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• pp.51-61
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• 1999

Pipeline is an important transportation mode for ail products. The popeline transportation and storage rates affect the popeline usage, and the popeline usage also affects the transportation revenue and operating costs of the popeline. The purpose of our study is to develop a decision support system simulating popeline transportation and storage rates for maximizing the utilization and profitability of the oil pipeline and apply it to the real situation. To do this, a simulation model to help the decision maker decide the rates of the oil pipeline is first proposed. Second, a simulation program is developed, which enables the user to evaluate the various scenarios of oil transportation and storage rates. Finally, this program is applied to the case study of oil industry in korea.

• Korean Journal of Environmental Agriculture
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• v.31 no.4
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• pp.378-380
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• 2012

BACKGROUND: In Korea, green manure has been cultivated for reducing chemical fertilizer application, maintaining soil fertility, and feeding livestock in winter season. We evaluated the phosphate balance under green manure-rice cultivating system with different removal rates of green manure for maintaining soil fertility. METHODS AND RESULTS: The barley and hairy vetch mixture was selected as the green manure in this study. The barley and hairy vetch was sowed at a rate of 135 and 23 kg/ha, respectively, without fertilizer application. Total aboveground biomass was 12000 (barley: 5400 kg/ha, hairy vetch: 6600 kg/ha) kg/ha, and these green manure were incorporated with different input rates before rice planting. The input rates of green manure in this study were 0 (NPK+0%), 25 (NPK+25%), 50 (NPK+50%), 75 (NPK+75%) and 100 % (NPK+100) and the standard fertilization (NPK) without green manure cultivation. All treatments were applied with standard fertilizer (N-P-K: 90-19.6-48.3 kg/ha) before rice planting. The highest rice yield was observed in NPK+50% which was 20% higher compared with NPK. The phosphate balance with different incorporation rates of green manure was-104.0,-76.8,-52.9,-27.4, and 6.0 kg/ha for NPK+0%, NPK+25%, NPK+50%, NPK+75%, and NPK+100%, respectively. CONCLUSION(S): The use of green manure for livestock feeding in green manure-rice cropping systems could remove a huge amount of phosphate. This cropping system strongly requires phosphate application before green manure seeding for maintaining soil fertility.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.4
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• pp.342-349
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• 1998

In order to evaluate the effects of nitrogen (N) rate and application method on the recovery of N fertilizer applied in spring and summer by Satsuma mandarins (cv. Miyakawa Wase), N as urea was surface-applied at the rates of 50 (applied with 20 mm water; 50% N application) and 100% (three treatments; applied as solid, with 5 or 20 mm water) of the recommended rate ($150kg\;ha^{-1}\;yr^{-1}$) on 25 March and 12 June with an application ratio of 50 and 20%. The labeled N was applied only once in spring or summer. There were no differences among the four treatments in fruit yield, fruit quality except acid content of juice, and N content of leaves. The recovery of fertilizer N applied in spring by a tree ranged from 7.8 to 8.3% and that of N applied in summer ranged from 11.3 to 14.2% at the three recommended N rates and was 18.0% for the 50% N application. The recovery of fertilizer N applied in spring in the upper 40 cm of soil ranged from 32.1 to 37.7% at the three recommended N rates and was 55.8% at the 50% N application. For N applied in summer, it was 69.8% for surface application of the recommended N rate and ranged from 80.7 to 84.4% for the three N applications with water. The total (tree+soil) recovery of N fertilizer applied in spring was highest (64.1%) for the 50% N application and ranged from 40.3 to 45.5% for the three recommended N rates. The total recovery of N fertilizer applied in summer was also highest (99.4%) for the 50% N application and tended to be higher for the application of N with water than surface application and to increase with increasing irrigation amount of N application.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.12
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• pp.949-954
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• 2011

In this study, the characteristics and error ranges of the mechanical bonding strength were analyzed according to before and after thermal shock test for various chips of automotive application component using Sn-3.0Ag-0.5Cu solder. In the after thermal shock test, the mechanical bonding strengths tend to decrease, meanwhile decreasing rates of mechanical strengths were less then 12% at specimen's bonding area below 3.5$mm^2$, and were from 17 to 21% at specimen's bonding area above 12 $mm^2$. On the other hand, Specimen's mean deviation rates were about 5% at specimen's bonding area more than 12 $mm^2$. Inversely, at specimen's bonding area is less then 3.5 $mm^2$, mean deviation rates were increased to about 8%. It means that the smaller device size is, the larger mean deviation rate. In addition, error ranges and deviation rates of the mechanical bonding strengths may differ slightly depending on their bonding area. Furthermore, process conditions as well as method of mechanical reliability evaluation should be established to reduce the error ranges of bonding strength.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.2
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• pp.131-138
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• 2000

This experiment was carried out during the period from September, 1997 to October, 1998 to determine the effect of fermented saw-dust pig manure (FSP) application on the herbage production on a mixed pasture in the Cheju brown volcanic ash soil. Split plot design (main plot: 3 nitrogen application levels of 0, 150 and 300 kgiha; sub plot: 4 pig sawdust manure levels of 0, 3, 6 and 12 tonha) was used. Plant height and dry matter yield increased significantly with an increase of nitrogen and FSP level. There was no difference in the botanical composition of grasses as affected by FSP application level, but herbage yields of grass species were increased by nitrogen application compared to that without nitrogen application. Botanical composition of white clover decreased with an increase of nitrogen application, but increased with an increase of FSP application level. Percentages of weeds were not affected by application rates of chemical nitrogen fertilizer and swine manure in the mixed species pasture. Nitrogen, phosphorus, and potassium contents of species in the pasture significantly increased with increasing application rates of nitrogen fertilizer. In conclusion, it would be an optimum to apply 150 kgha of inorganic chemical fertilizer and plus either 3 or 6 toniha of fermented swine manure with sawdust for optimum production of mixed pasture on Cheju Island. (Key words : Herbage production, Botanical composition, Morphology, Plant mineral contents)

• Korean Journal of Environmental Agriculture
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• v.28 no.3
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• pp.243-248
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• 2009

Chinese cabbage cultivation has been typically practiced in alpine sloped farmland in Gangwon province, and caused severe soil erosion by soil disturbance like tillage. Cultivation of wild edible greens such as Aster scaber Thunb. and Ligularia fischeri Turcz. could be one of alternative ways to reduce soil erosion, because their residues become stubble mulch after harvest, and there is no need for tillage every year. Therefore, the objective of this research was to estimate the effect of nitrogen application rates for the maximum production of Aster scaber Thunb. and Ligularia fischeri Turcz. in the early cultivation stages. Total N contents of Aster scaber Thunb. and Ligularia fischeri Turcz. increased with the increment of fertilizer application rates. Maximum growth of Aster scaber Thunb. and Ligularia fischeri Turcz. was observed with the highest rates of fertilizer. We obtained the relationship between Aster scaber Thunb. and N application rate, as y = $-0.296x^2$ + 73.82x + 5246 (R = 0.998). There was no significant difference for Aster scaber Thunb production between N application rates for 120 and 160 kg/ha. Also, the relationship between Ligularia fischeri Turcz. and N application rate was y = $-0.135x^2$ + 32.86x + 1529 ($R^2$ = 0.965) in the first year trial after transplanting.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.2
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• pp.105-110
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• 1989

The purpose of this study was centered on investigation of the effects N, P and K application rates on root yield and their available content (catalpol, sugar, ash and extracts) of Ji-whang(Rehmannia glutinosa Lib. var. purpurea Makino), and the current application rates(N 20kg/10a, $P_2O_5\;30kg/10a$, $K_2O\;20kg/10a$) was studied for Ji-whang production in Eui-sung Gun southeastern part of Korea Peninsular. The yields of fresh and dried rhizomas were 941-1,494 kg/10a and 251-385 kg/10a, respectively. The rhizoma yield increased highly with increasing the application amount of nitrogen more than 10 kg/10a, but the effects of phosphorus and potassium were observed only at the application level of 40 kg/10a and 20 kg/10a, respectively. Catalpol contents in rhizoma increased at the plot of 20 kg/10a application of nitrogen, but the effects phosphorus and potassium on the catalpol contents were not observed. Catalpol content in dried root increased with increasing N application more than 10 kg/10a. Fructose contents increased at the plot of 20 kg/10a and more N application, and galactose contents decreased with K application. With increasing N application, ash contents decreased, but ethanol extract contents increased.