• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.243-251
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• 2011

BACKGROUND: Gypsum($CaSO_4{\cdot}2H_2O$) is known as an ideal amendment to improve soil quality of the reclaimed coastal land. Since gypsum has very high concentration of electron acceptor like ${SO_4}^{2-}$, its application might be effective on reducing $CH_4$ emission during rice cultivation, but its effect has not been studied well. METHODS AND RESULTS: The effect of gypsum on $CH_4$ emission and rice growth characteristics was studied by pot test, which was packed by reclaimed paddy soils collected from Galsa, Hadong, Gyeongnam province. Chemical-grade gypsum was applied in two soils having EC 2.25 and 9.48 dS/m at rates of 0, 0.5, 1.0 and 2.0%(wt/wt). $CH_4$ emission was characterized a week interval by closed chamber method during rice cultivation. $CH_4$ emission rate was significantly decreased with increasing salt accumulation and gypsum application levels. With increasing gypsum application, dissolved ${SO_4}^{2-}$ concentration in the leachate water was significantly increased, which might have suppressed $CH_4$ production in soil. Total $CH_4$ flux was dramatically decreased with increasing gypsum application. In contrast, rice yield was increased with increasing gypsum application and then achieved maximum productivity at 1.0% gypsum application in two soils. CONCLUSION(s): Gypsum is a very good soil amendment to suppress $CH_4$ emission in reclaimed coastal paddy soils, and improve rice productivity and soil properties. The optimum application level of gypsum is assumed at ca. 1% to improve soil productivity with reducing effectively $CH_4$ emission during rice cultivation.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.2
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• pp.71-78
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• 2012

Eupatilin, one of representative medical components of mugwort, can be efficiently extracted from the 'Gangwha Sajabalssuk'. The Eupatilin content may depend on environmental factors such as soil and regional climate in addition to a genetic factor and Gangwha region has a profitable environmental condition for the mugwort growth. In this study, the climatological characteristics of Gangwha was analyzed in order to find the environmental condition of mugwort containing high Eupatilin in term of atmospheric, oceanographic and land variables. The climate of Gangwha is characterized by the relatively low daily temperature and large diurnal variation with plenty of solar radiation, long sunshine duration and less cloudiness. According to our correlation analysis, the long sunshine duration and the large diurnal temperature variation are highly correlated with the Eupatilin contents. The result implies that Gangwha has the favorable conditions for the cultivation and the habitat of the high-Eupatilin concentrated mugwort. Because of the sea surrounding Gangwha Island with low salinity and moderate wind, the salt contained in sea breeze is relatively low compared to other regions. Furthermore, Gangwha has clean atmospheric environment compared to other regions because the concentrations of toxic gases harmful to crop growth such as nitrogen dioxide ($NO_2$), sulfite gas ($SO_2$) and fine dust (PM-10) are lower in the air. The ozone ($O_3$) concentration is moderate and within the level of natural production. It is also found that moderately coarse texture or fine loamy soils known as good for water drainage and for the growth and cultivation of the 'Gangwha-mugwort' are distributed throughout the areas around mountainous districts in Gangwha, coinciding with those of mugwort habitat.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.162-168
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• 1996

Effects of temperature, pH and addition of NaCl and quinine on sweetness and recognition threshold of aspartame were investigated. Changes in flavor of some foods were also studied when aspartame was added. The sweetness of 0.02% aspartame, the equi-sweetness of 4.3% sugar, was organoleptically evaluated by multiple comparison test at variouse range of temperature ($4^{\circ}$, $20^{\circ}$, $40^{\circ}$, $60^{\circ}$ and $80^{\circ}C$), pH (3.0, 4.5, 6.0 and 7.5), NaCl (0.5, 1.0, 1.5 and 2.0%) and quinine (0.001, 0.003 and 0.005%). The highest sweetness was obtained at $20^{\circ}C$ and pH 3.0-4.5. Addition of NaCl at 0.5% level showed the highest sweetness which was decreased thereafter. The sweetness was significantly decreased by the addition of quinine. The recognition threshold of aspartame was the lowest at $20^{\circ}C$ and pH 3.0-4.5. Lower in bitterness and higher In ginseng flavor were noted in ginseng tea with aspartame than in that without aspartame. Improved roasted flavor and decreased undesirable odor and taste were resulted in soymilk with the addition of aspartame. The flavors of orange, apple and strawberry were enhanced by aspartame in orange juice, apple juice and strawberry juice, respectively.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.157-161
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• 1996

Physicochemical and microbial characteristics of traditional kochujang (fermented hot pepper-soybean paste) collected from 55 households at different regions were investigated. The traditional kochujang contained $46.71{\pm}5.98%$ moisture, $46.87{\pm}8.83%$ total sugar, $11.77{\pm}3.90%$ crude protein, $15.01{\pm}6.48%$ salt, $27.52{\pm}7.32%$ reducing sugar, $0.26{\pm}0.15%$ amino nitrogen and $2.69{\pm}2.35%$ ethanol. The pH and titrable acidity were $4.60{\pm}0.23$ and $27.26{\pm}10.98\;ml/10\;g$, respectively. The average water activity of traditional kochujang were $0.79{\pm}0.04$. The Hunter L, a, and b values of kochujang were $16.03{\pm}2.89$, $20.42{\pm}4.37$, and $9.71{\pm}1.92$, respectively. The viable cell counts of aerobic, anaerobic bacteria and yeasts in the traditional kochujang were $1.02{\times}10^8{\pm}1.29{\times}10^8\;CFU/g$, $2.24{\times}10^7{\pm}3.90{\times}10^7\;CFU/g$ and $5.90{\times}10^5{\pm}2.25{\times}10^6\;CFU/g$, respectively. The kochujang collected from various regions showed quite strong liquefying and saccharogenic amylase and protease at different level by samples.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1091-1097
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• 2002

In order to improve palatability and quality of traditional kochujang, kiwifruit (Actinidia deliciosa) was added to traditional kochujang fermented for 3 months. Physicochemical and microbial characteristics were investigated during fermentation at $30^{\circ}C$. Moisture contents of all treated kochujangs increased with increasing amount of kiwifruit added during fermentation. pH of kiwifruit-added kochujang was lower than that of the control kochujang, whereas no significant differences in titratible acidity was observed among all treatments. Crude protein and salt contents of kiwifruit-added kochujang were lower than those of the control, whereas no difference in crude fat contents were found. Ethanol and amino-nitrogen contents of 6 and 9% kiwifruit-added kochujang were higher than those of the control. Fructose contents of kiwi-added kochujangs were higher than that of the control. Major organic acids of kochujang were in the order of malic acid > citric acid > succinic acid > acetic acid > lactic acid > oxalic acid. Succinic acid level increased significantly during fermentation and was higher in kiwifruit-added kochujang than in the control. Bacterial cell counts of all treatments were not different, and viable cell count of yeast was slightly higher in kiwifruit-added kochujang only at the initial fermentation period. Sensory evaluation revealed that the addition of 9% kiwifruit was the optimum condition for improving kochujang quality.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1365-1370
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• 2000

Deonjang prepared with sea salts(Shinan-docho product, Thai-land product, refined product and Austrailia salt product) were analyzed for pH, acidity, reducing sugar, amino type nitrogen and free amino acids. Amino type nitrogen as major element was highest in fermenting for 30 days as 315.3 mg% in deonjang prepared with Shinan-docho salts, but deonjang prepared with imported salts were $265.1{\sim}263.3\;mg%$. Sum of free amion acids for 30 days were 4,527 mg% in deonjang prepared with Shinan-docho salts, but lower in deonjang prepared with imported salts. Each amino acid content of deonjang prepared with Shinan-docho salts, which were glutamic acid and aspartic acid had much higher level than others.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.3
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• pp.171-177
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• 2010

As concrete structures are exposed to chemical substances, damaged from salt, or progressed to the neutralization, the surface damage of the structures is generated timely fashion, resulting shortened service life. Especially, the sulfate erosion causes rapid surface defects, and the steel skeleton becomes corroded due to the water infiltration, generating stability deterioration of the concrete structure. In this study, the physical characteristics of the acid-resistant mortar with aluminosilicates was investigated in order to resolve problems of the acid resistance, one of the most serious problems of the cement type repair material. As the result of the experiment, the test specimen turned to exhibit almost equivalent physical characteristics with those of concrete sectional repair materials in terms of compressive and bending strengths. As both the cement sectional repair material and the test specimen were immerged in sulfuric acid solution to examine weight changes, the test specimens exhibited only 4% loss of their weights while the cement sectional repair materials reached at the level of 80% or above, proving the excellence acid resistant characteristics of the test specimens. Consequently, the physical characteristics of acid resistant mortar with aluminosilicates were revealed to be superior than those of concrete sectional repair materials. It can be utilized as a sectional repair material where the acidic erosion is anticipated.

• Food Science and Preservation
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• v.24 no.3
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• pp.413-420
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• 2017

This study was designed to examine the in vitro antioxidant and anti-inflammatory effects of red beet (Beta vulagaris) root. Red beet root was extracted using 70% ethanol and then fractionated sequentially with n-hexane, ethyl acetate and butanol. Antioxidative ability was evaluated by bioassays using total polyphenol contents and ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid diammonium salt) radical scavenging activity. Ethyl acetate fraction of red beet root was best on total polyphenol contents ($37.02{\pm}0.37mg\;GAE/g$) and ABTS radical scavenging effects ($IC_{50}$ $42.9{\pm}9.5{\mu}g/mL$). For the anti-inflammatory activity in RAW264.7 cells, the hexane fraction showed the highest inflammatory effect. Dose response studies were performed to determine the inhibitory effect of hexane fraction of red beet root on pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The hexane fraction of red beet root inhibited the NO and $PGE_2$ production and the protein level of iNOS and COX-2, and protein expression of pro-inflammatory cytokines ($TNF-{\alpha}$, IL-6 and $IL-1{\beta}$), in a dose-dependent manner. These results suggest that red beet root has considerable potential as a functional food ingredient with antioxidative and anti-inflammatory effects.

• Korean Journal of Construction Engineering and Management
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• v.20 no.2
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• pp.113-118
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• 2019

Recently, the maintenance concept of infrastructure has been changed from the stability management of the structure determined by the safety inspection of the existing facilities to the asset management related to evaluating and managing the performance of the facilities. For management of the property of the facilities, it is necessary to efficiently classify their information for the maintenance and service level of the facilities and to manage them. In the case of power plant facility, especially, it is a complex structure, which is constructed in a various component and detail. In this study, therefore, the components of power plant facility were classified into facilities, spaces, parts, and elements considering the type of integrated construction classification system in Korea. To reflect the deterioration rate of the facility in accordance with environmental conditions such as airborne salt and humidity etc., it was classified by adding direction, interior, and exterior condition of each component not to be considered in the existing classification system for its effective and systematic maintenance, since it is generally located in the coastal area due to the operation of the power generation structure. The classification system developed in this study can be used as fundamental data for development of the computer system for asset management of power plant facility.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.3
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• pp.41-48
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• 2019

Mixed expeller cake has been one of soil management to improve crop productivity and soil fertility. But, there was a little information on optimum mixed expeller cake application for chinese cabbage. So, in this study, we were evaluated the preplant optimum application rate of mixed expeller cake(MEC) in chinese cabbage cultivation at field. Treatments consist of control, inorganic fertilizer($N-P_2O_5-K_2O$ : $320-78-198kg\;ha^{-1}$), MEC(50, 100, 150% on preplant application standard $110kg\;ha^{-1}$ as N, topdressing : $210kg\;ha^{-1}$ as N). In results, growth characteristics was not significantly different. But, yield was increased when application rate was increased. And MEC 150% treatment showed similar yield as inorganic treatment. There was no significant difference in soil pH, OM, $Av.P_2O_5$, $NH_4-N$ and Ex.K. But, soil EC and $NO_3-N$ were increased when MEC level increased. As a results, MEC 150% can be proposed as preplant optimum application rate of MEC from this study. But abuse of MEC and long-term using caused about salt accumulation in soil.