• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.1
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• pp.1-6
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• 2005

With recent interest organic farming the use of legumes including vetch and clover to provide N to adjacent crops is increasing in Korea. In the present studies, we conducted a trial to investigate the effects of the application of N rate on nitrogen fixation and transfer from vetch to barley in mixed stands. The experiment was arranged in a randomized complete block design with three replications. Four different N rates(0, 75, 113 and 150/ha) was used and vetch+barley was broadcasted manually on 1.5 $\times$2 m plot in Oct. 2001. Half of urea and K$_{2}O, 200 Phosphate and 75 kg potash per ha were applied as basal dressing md half of N md 75 potash were used for topdressing to soil surface on MarctL 2002. The equivalent of 1kg ha$^{-1}$ at($^{15}$NH$_{4}$)$_{2}$SO$_{4}$ solution at 99.8 atom $\%$$^{15}$N excess was applied to the microplot in mid April. Forage was harvested from each plot at ground level and separated into barley and vetch. Total N content and It values of samples were determined using a continuous flow stable isotope ratio mass spectrometry(IsoPrime-EA. Micromass, UK.). The percentage of legume H fixed from atmospheric N2 were 95.0, 93.8, 94.4 and $84.8\%$ with increment of N levels. The percentage of N transfer from vetch to barley by N-difference method with increment of N fertilizer were from 58 to$49\%$ while 39 to $23\%$ in $^{15}$N-dilution method. The amount of transfer from vetch to barley were 87 to 68 kg/ ha with N level by N-difference moth여 and 58 to -56/ha with N application levels by $^{15}$N dilution method. The amount of nitrogen fixation per ha were from 150 kg / ha to 219 kg / ha by different method, but on the other side 49 to 105kg/ha by N$^{15}$-dilution.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.2
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• pp.85-92
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• 2002

This study was conducted to investigate the effects of application levels of swine waste and chemical fertilizer on productivity of corn and nitrogen and phosphorus leaching in Lysimeter containing sandy loam soil. Main Plots were consisted of two types of swine waste, such as swine slurry(SS) and compost of swine manure fermented with sawdust(CSMFS), and chemical fertilizer(CF) and the subplots were consisted of application levels of N-fertilezer, such as 100kgN/ha, 200kgN/ha and 400kgN/ha. Lysimeters were constructed with 1m depth, 30cm diameter. The results obtained were summarized as follows ; 1. Dry matter(DM) yield of com enhanced as increased application levels of SS, CSMFS and CF. DM yield reveals that there is an increase in order CS > SS > CSMFS. 2. Nitrogen contents of the whole corn enhanced as increased application levels of SS, CSMFS and CF. Nitrogen content reveals that there is an increase in order CS > SS > CSMFS. 3. $NO_3^{-}$ and P contents in the leaching water increased as increased application levels of SS, CSMFS and CF. $NO_3^{-}$ content was highly elevated in the concentrated rainy season in the experimental early stage. However, P content was affected with the rainfall. The maximum $NO_3^{-}$ and P contents in the leaching water were 14.8ppm and 0.26ppm, respectively.ively.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.4
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• pp.217-227
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• 2007

The western cherry fruit fly, Rhagoletis indifferens Curran (Diptera:Tephritidae), is the most important pest of cultivated cherries in the Pacific Northwest area of the United States, being widely distributed throughout Oregon, Washington, Montana, Utah, Idaho, Colorado and parts of Nevada. The control of R. indifferens has been based on calendar sprays after its first emergence because of their zero tolerance for quarantine. Therefore, a good prediction model is needed for the spray timing. This study was conducted to obtain the empirical population dynamic information of R. indifferens after overwintering in the major cherry growing area of the Pacific Northwest of the United States, where the information is critically needed to develop and validate the prediction model of the fruit fly. Adult fly populations were monitored by using yellow sticky and emergence traps. Larvae growth and density in fruits were observed by fruit sampling and the pupal growth and density were monitored by pupal collection traps. The first adult was emerged around mid May and a large number of adults were caught in early June. A fruit had more than one larva from mid June to early July. A large number of pupae were caught in early July. The pupae were collected in various period of time to determine the effect of pupation timing and the soil moisture content during the winter. A series of population density data collected in each of the developmental stage were analyzed and organized to provide more reliable validation information for the population dynamic models.

• Journal of Bio-Environment Control
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• v.10 no.2
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• pp.80-87
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• 2001

This study was conducted to provide basic data for the design of shading facility of greenhouse. The proper distance between external shading screen and roof surface, transmissivity of shading materials, and shading effects of external and internal shadings were analyzed. About a distance of 10 cm between inclined external shading screen and roof surface was enough to guarantee the external shading effect in the greenhouse without roof vent. The inside temperature of greenhouse installed with 85% internal shading screen was lower the maximum of 4$^{\circ}C$ and mean of 2$^{\circ}C$ than that with 55% internal shading screen in both natural ventilation and no ventilation condition. The difference of soil temperature between shading and no shading greenhouse was great, but the difference by shading rate or shading method was small. The performance of external shading for controlling inside temperature down was superior to that of the internal shading. The externally inclined shading screen parallel to the roof surface of greenhouse was more effective than the externally horizontal shading screen in controlling inside temperature of greenhouse without roof vent.

• The Journal of Engineering Geology
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• v.30 no.2
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• pp.185-198
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• 2020

High-density rapid expansion material is a method that increases the solid volume of injection materials due to hydration and foam reactions at the same time as spraying. It is an effective method for securing ground stability, restoring subsidence, and loading during construction of structures. In this regard, through the mechanical experiments of injection materials, the stability of the foundation ground of the structure and the effect of increasing the endurance using site construction were analyzed. The results of the experiment showed that the unit weight of soil decreased by 10.5% after injection of the filling material, and the allowable support for the structure was deemed safe, and the subsidence by each section after ground improvement was determined to be safe at 2.28, 1.55 and 0.46 cm, respectively, with an acceptable subsidence of less than 5 cm. After the field test, five inclinometers were installed on the top floor of the target building to measure the displacement of the X and Y axes. As a result of the measurement, no displacement related to the phenomenon of inequality or subsidence cracks of the structure was measured for about 16 months (509 days) after construction. This can be judged to be a sufficient increase in the stability of the ground after the injection of rapid expansion.

• Journal of Environmental Impact Assessment
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• v.27 no.3
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• pp.241-250
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• 2018

Recently, negative effects on human health such as disease caused by harmful environment have been dealt with seriously. In particular, studies on the effect of radon exposure, which is known as a primary carcinogen in lung cancer due to radioactive materials, have been actively studied. In Korea, since January 1, 2018, radon measurement is mandatory when building a new apartment, so it is necessary to measure the radon concentration and submit it to the local government and it should be posted where residents can see it. Radon has only recommended standards for multi-use facilities, but now it has decided to set recommendation standards for private homes. Therefore, it should now be possible to manage the radon in the environmental impact assessment phase as well as in the Post-environmental Impact Assessment. It should be possible to share health information such as the radon concentration and the risk of radon, and participation of health experts in the environmental impact assessment stage is required. Soil, air quality, hygiene and aerial items should be improved to take into account the effects of radon on human health during the environmental impact assessment process. If the level value of conncentration of radon shows above the recommended level, then alternative measures should be prepared and mitigation measures should be prepared as well.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.5
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• pp.1-13
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• 2017

Recently, due to worldwide industralization and urbanization, natural environment has been severly damaged and global warning is worsening. Heat wave, torrential rainfall, typhoon and other natural disasters continuously occur due to global warming. Policies such as carbon emission regulation are taken into effect to solve such problems. Such global trend has affected interest to natural ecosystem and developed as a concept of ecosystem-services. This study particularly focused on ground water storage capacity among various ecosystem-services such as climate control and soil formation. It is because Korea suffers from drought and flood every year. Therefore, this study aims to understand objective numerical value of ecosystem-services value regarding ground water storage capacity of biotop classes based on relationship among precipitation, amount of evapotranspiration, and runoff of 7 regions of Chilgok-gun, Gyeongsangbuk-do and to convert the value into economic value. The study calculated ground water storage capacity based on relationship among precipitation, amount of evapotranspiration, and run off. Calculated amount of each capacity was 29.26 million ton($30.2mm/m^2$), 430.46 million ton($140.4mm/m^2$), 11.30 million ton($150.1.0mm/m^2$), 33 milion ton($3.0mm/m^2$). Economical value of ecosystem-service by each biotop classes appeared 4,128,800 thousand KRW ($21.32KRW/m^2$) for agricultural biotop, and 60,403,600 thousand KRW ($98.52KRW/m^2$) for forest biotop, 1,572,800 thousand KRW ($104.4KRW/m^2$) for grassland biotop, and 47,600 thousand KRW ($2.18KRW/m^2$) for bare ground biotop. The result of this study like above, it will be used as important evidentiary material to preserve natural resource effectively from various development business and policies that damages natural eco-system. Also, it is judged that ecosystem-service value by each land coverage will be used as important material for preparing legalistic institution such as establishing natural environment preservation plan, budget for alternative forest resource creation cost.

• Korean Journal of Food Science and Technology
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• v.47 no.3
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• pp.281-285
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• 2015

An oleaginous fungus was isolated from soil and identified as Mortierella sp. (M-12) for producing arachidonic acid (AA). Cell disruption methods, extraction methods, and particle sizes of freeze-dried biomass were tested to achieve maximum extraction of total lipids and AA. M-12 grown in glucose yeast media at $25^{\circ}C$ for 7 days contained 35.5% total lipid, and 47% of the total lipid was AA. Lipid extraction yield from wet biomass was shown to be similar to that in a dry state. Maximum lipid extraction was achieved using a mixture of chloroform and methanol (2:1) as an extraction solvent. Different mechanical cell disruption methods did not affect lipid extraction yields. The smaller the particle size of the biomass, the better the lipid extraction yield was observed. Particle size of biomass was shown to more strongly affect lipid extraction than extraction time. The highest AA content was observed in the class of neutral lipids.

• Microbiology and Biotechnology Letters
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• v.31 no.1
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• pp.42-45
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• 2003

A Trichoderma sp. SO-571 producing cellulase was isolated from soil, and a pilot-scale cultivation and separation of cellulase were conducted. The cellulase activity was about 14.5 unit/ml after 112 hr of cultivation in a 301 fermenter containing 3.0% cellulose, 4.0% soybean powder, 3.0% wheat bran, 0.5% ($NH_4$)$_2$$SO_4$0.2% urea, 1.0% CSL, 0.5% $KH_2$PO$_4$, and 0.2% Tween 80. The cellulase was purified over 4.6 folds in three steps with 47.86% yield. The optimum pH of cellulase was pH 5.0 and optimum temperature was $60^{\circ}C$. To investigate the effect of the cellulase-treated cellulosic fabric, the weight loss was compared. The weight loss of denim treated with cellulase from Trichoderma sp.SO-571 was 2.9% and that with Celluclast 1.5L was 2.2%. In tencel treatement with enzyme, cellulase showed 0.7% higer weight loss than that with Celluclast 1.5L.

• Journal of Animal Environmental Science
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• v.13 no.1
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• pp.53-58
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• 2007

This study was carried out to determine the effect of continuous application of animal liquid slurry on the growth and yield of rice in 2005. Field experiment was conducted under variable continuous application years of animal liquid slurry; 1, 3, 5 application years of slurry and chemical fertilizer as control plot. The effects of different application years of slurry on the growth characteristics and yield of rice were determined. The plant height and tiller's number of 1 year application of liquid slurry were lower than those of the chemical fertilizer plot. But in the plot of 5 years continuous application of animal slurry, the height and tillers of rice were higher than those of 1 year application. And the color of leaf 5 years application years plot was darker than that of the chemical fertilizer. Yield of the 5 years continuous application of slurry was 4% higher than that chemical fertilizer, but that of 1 year application was decreased 6% compared with chemical fertilizer. The long time application of animal slurry was increased content of organic matter, $P_2O_5$ and exchangeable caution(K) in soil.