• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.380-387
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• 2016

This study was performed to select potentially available biological control agent from soil bacteria for prevention of ginseng damping off. More than five hundred strains were isolated from ginseng rhizosphere soil. By testing antifungal activity, we have selected three soil bacteria strains and their ability to produce antibiotics and lytic enzymes such as cellulase, protease and pectate lyase was examined. Also, the presence of genes for biosynthesis of lipopeptide such as fengycin, bacillomycin D, surfactin, iturin A, and zwittermicin A was investigated in selected strains. All three strains produced cellulase, protease, and xylanase. Moreover, these strains had gene for biosynthesis of bacillomycin D, surfactin, and iturin A. ES1 and ES3 strains were identified Bacillus methylotrophucus and ES2 was confirmed Bacillus amyloliquefaciens using phylogenetic analysis on the basis of 16S rRNA gene sequences. In field test, control value of ES1, ES2 and ES3 treatment was 32.4%, 46.8% and 36.7%, respectively. This results indicate that antagonistic microbes with high ability of antifungal and lytic enzyme activity can be used as a useful biological control agent to control ginseng damping off.

• Journal of Life Science
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• v.25 no.6
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• pp.680-685
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• 2015

Previously, cellulase and xylanase producing microorganism, Bacillus subtilis NC1, was isolated from soil. Based on the 16S rRNA gene sequence and API 50 CHL test the strain was identified as Bacillus subtilis, and named as B. subtilis NC1. We cloned and sequenced the genes for cellulase and xylanase. Plus, the deduced amino acid sequences from the genes of cellulase and xylanase were determined and were also identified as glycosyl hydrolases family (GH) 5 and 30, respectively. In this study to optimize the medium parameters for cellulase production by B. subtilis NC1 the RSM (response surface methodology) based on CCD (central composite design) model was performed. Three factors, tryptone, yeast extract, and NaCl, for N or C source were investigated. The cellulase activity was measured with a carboxylmethyl cellulose (CMC) plate and the 3,5-dinitrosalicylic acid (DNS) methods. The coefficient of determination (R²) for the model was 0.960, and the probability value (p=0.0001) of the regression model was highly significant. Based on the RSM, the optimum conditions for cellulase production by B. subtilis NC1 were predicted to be tryptone of 2.5%, yeast extract of 0.5%, and NaCl of 1.0%. Through the model verification, cellulase activity of Bacillus subtilis NC1 increased from 0.5 to 0.62 U/ml (24%) compared to the original medium.

• Korean Journal of Environment and Ecology
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• v.22 no.6
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• pp.691-706
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• 2008

This study analysed problems of railroadside buffer green space and suggested planting methods according to space function and planting concept in seashore reclaimed land, Ansan city. Planting density of railroadside buffer green zone of Ansan city was $0.04{\sim}0.17tree/m^2$, GVZ was $0.15{\sim}1.65m^3/m^2$ which is represented of deficiency of buffer function. In addition, soil hardness of mounded buffer green zone was $2.72{\sim}15kg/cm^2$. It was examined to have functions in terms of habitat for wildbirds and other organisms, surrounding landuse, urban greens, seasonality, landscape for function improvement of buffer green space. Functions of buffer green space were re-established as habitat for organism, buffer and landscape improvement, landscape and urban park, buffer zone and habitat. It was suggested to select Pinus thunbergii as a dominated species of planting method for buffer function and planting density in canopy and under-canopy layer was $0.4tree/m^2$, $0.5/m^2$ in shrub layer. In terms of landscape improvement function, Zelkova serrata, Prunus sargentii and Prunus armeniaca were selected as major species and it in canopy and under-canopy layer was $0.2tree/m^2$ and $0.5tree/m^2$ in shrub layer. In terms of habitat function Quercus acutissima, Prunus sargentii and Sorbus alnifolia were as major species and it in canopy layer was $0.06tree/m^2$, $0.1tree/m^2$ in under canopy layer, $0.8tree/m^2$ in shrub layer.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.12
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• pp.667-675
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• 2016

Nanoscale zero-valent iron (nZVI) has been effectively applied for environmental remediation due to its ability to reduce various toxic compounds. However, quantification of nZVI reactivity has not yet been standardized. Here, we adapted colorimetric assays for determining reductive activity of nZVIs. A modified indophenol method was suggested to determine reducing activity of nZVI. The method was originally developed to determine aqueous ammonia concentration, but it was further modified to quantify phenol and aniline. The assay focused on analysis of reduction products rather than its mother compounds, which gave more accurate quantification of reductive activity. The suggested color assay showed superior selectivity toward reduction products, phenol or aniline, in the presence of mother compounds, 4-chlorophenol or nitrobenzene. Reaction conditions, such as reagent concentration and reaction time, were optimized to maximize sensitivity. Additionally, pretreatment step using $Na_2CO_3$ was suggested to eliminate the interference of residual iron ions. Monometallic nZVI and bimetallic Ni/Fe were investigated with the reaction. The substrates showed graduated reactivity, and thus, reduction potency and kinetics of different materials and reaction mechanism was distinguished. The colorimetric assay based on modified indophenol reaction can be promises to be a useful and simple tool in various nZVI related research topics.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.3
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• pp.64-73
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• 2013

The application of the Life Cycle Assessment (LCA) methodology to analyze the environmental impact to different swine waste treatment systems was investigated. The first part of LCA is to organize an inventory of parameters and emissions released due to the system under investigation. In the following step of the Life Cycle Impact Assessment, the inventory data were analyzed and aggregated in order to finally get one index representing the total environmental burden. For the Life Cycle Impact Assessment (LCIA) the Eco-indicator 95 method has been chosen because this is well documented and regularly applied impact method. Two different swine waste treatment systems such as aerobic and anaerobic digestion systems were chosen as an example for the life cycle impact analysis. For establishing the parameters to be assessed the agricultural environmental effects to above swine waste treatment systems, it has been observed that there was high at T-P emission in anaerobic digestion system and $CO_2$ emission in aerobic digestion system. For Eco-indicator values per environmental effect for swine waste treatment systems related to one tonne of swine waste, it was shown that there was a negative index for global warm potential and soil acidification in aerobic digestion system, but relatively high positive index for eutrophication in anaerobic digestion system.

• Microbiology and Biotechnology Letters
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• v.32 no.1
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• pp.78-83
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• 2004

In order to screen microorganisms producing phopholipase D (PLD) had high transphosphatidylation activity, about 1,000 Actinomycetes strains were isolated from the 63 soil samples, collected over 6 local area in Korea. When the hydrolytic activity in the supernatant was determined, 131 strains produced PLD more than 0.3U/$m\ell$. Among 131 culture broths tested, 23 ones had transphosphatidylation activity higher than 20% and finally one strain (Actinomycetes KF923), which had highest hydrolytic and transphophadylation activity, was selected. Actinomycetes KF923 showed the highest hydrolytic activity (13U/$m\ell$) and phosphatidylation activity (95%) after 48 h fermentation using the P medium (yeast extract 1%, peptone 1%, glucose 1.5%, glycerol 1%, $CaCO_3$ 0.4%, pH 7.2). PLD was purified from the culture broth of Actinomycetes KF923 and the specific activity of purified PLD was 567U/mg. The molecular weight of PLD was about 55kD and the optimum pH and temperature were pH 6.0 and $60^{\circ}C$, respectively. The stability of PLD toward pH and temperature were high around pH 8.0 and below $40^{\circ}C$ Special metal ions were not necessary to the PLD activity.

• Journal of the Korean GEO-environmental Society
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• v.18 no.8
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• pp.23-32
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• 2017

For exposed slopes, the weathering degree over time has a major effect on the engineering properties of rocks and the slope stability. Rocks are gradually changed by weathering into soil over time, and the resulting physical, chemical and mechanical changes of rocks affect the engineering stability of the slope. However, there are not many ways to objectively evaluate the weathering degree of a slope. In this study, therefore, to investigate the weathering characteristics of rocks, granite, gneiss and shale distributed in the Chungbuk region were sampled by weathering stage and changes in their component minerals and tissues were investigated. Furthermore, artificial weathering was induced using the freezing and thawing test and quantitatively investigated through porosity and absorption rate. In addition, the changes of microcracks due to artificial weathering were evaluated through box fractal dimension ($D_B$). Through mineralogical study the phase change of constituting minerals, the growth of secondary minerals, the development of micro-cracks and the fabric changes due to weathering were observed. The mineralogical, chemical and engineering evaluations of the weathering degree through the experimental results in this study are expected to be useful for analyzing the weathering characteristics and causes by rock type and for proposing a methodology to evaluate the degradation of physical properties comparatively and quantitatively.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.3
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• pp.117-127
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• 2020

The Early Warning System for agrometeorological hazard of the Rural Development Administration (Korea) forecasts detailed weather for each farm based on the meteorological information provided by the Korea Meteorological Administration, and estimates the growth of crops and predicts a meteorological hazard that can occur during the growing period by using the estimated detailed meteorological information. For verification of early warning system, automated weather observation network was constructed in the study area. Moreover, a real-time web display system was built to deliver near real-time weather data collected from the observation network. The meteorological observation system collected diverse meteorological variables including temperature, humidity, solar radiation, rainfall, soil moisture, sunshine duration, wind velocity, and wind direction. These elements were collected every minute and transmitted to the server every ten minutes. The data display system is composed of three phases: the first phase builds a database of meteorological data collected from the meteorological observation system every minute; the second phase statistically analyzes the collected meteorological data at ten-minutes, one-hour, or one-day time step; and the third phase displays the collected and analyzed meteorological data on the web. The meteorological data collected in the database can be inquired through the webpage for all data points or one data point in the unit of one minute, ten minutes, one hour, or one day. Moreover, the data can be downloaded in CSV format.

• The Journal of the Korea Contents Association
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• v.12 no.11
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• pp.458-468
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• 2012

The purpose of this study is to define U-Eco City services and to analyze the possibility and easiness of application in urban space. The most significant meaning of this study is that these results could be used as the design and planning guidelines for integrated U-Eco City. This study progress as follows; First, U-Eco City concept and their services were defined and the spatial units of U-Eco City were distinguished through literature review. Second, U-Eco City spaces are classified into four levels such as building, street, facility and district. Finally, the application of U-Eco city services was analyzed together by the statistical technique of cross-tabulation. 35.7% of U-city services was serviced in urban district and 38.8% of Eco City services was applied to Building. U-City and/or Eco city services were adapted differently according to the urban spatial hierarchy. Those services should be applied in terms of the characteristics of urban space in designing and planning U-Eco City.

• Microbiology and Biotechnology Letters
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• v.31 no.4
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• pp.389-394
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• 2003

In order to screen microorganisms producing phopholipase D (PLD) had high transphosphatidylation activity, about 1,000 Actinomycetes strains were isolated from the 63 soil samples, collected over 6 local area in Korea. When the hydrolytic activity in the supernatant was determined, 131 strains produced PLD more than 0.3 U/ml. Among 131 culture broths tested, 23 ones had transphosphatidylation activity higher than 20% and finally one strain (Actinomycetes KF 923), which had highest hydrolytic and transphophadylation activity, was selected. Actinomycetes KF923 showed the highest hydrolytic activity (13 U/ml) and phosphatidylation activity (95%) after 48 h fermentation using the P medium (yeast extract 1%, peptone 1%, glucose 1.5%, glycerol 1%, $CaCo_3$ 0.4%, pH 7.2). PLD was purified from the culture broth of Actinomycetes KF923 and the specific activity of purified PLD was 567 U/mg. The molecular weight of PLD was about 55 kD and the optimum pH and temperature were 6.0 and $60^{\circ}C$, respectively. The stability of PLD toward pH and temperature were high around pH 8.0 and below $40^{\circ}C$. Special metal ions were not necessary to the PLD activity.