• Korean Journal of Soil Science and Fertilizer
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• v.27 no.3
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• pp.189-194
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• 1994

This experiment was conducted to obtain basic information on the improved methods of soil physico-chemical properties and sweet potato yield cultivated on a newly-reclaimed land, a Songjeong loam soil. The crop was cultivated under the six different treatments for 4years since 1985 in the field conditions. Annual changes of soil properties and sweet potato yield were investigated and analyzed. Soil bulk density increased from the second year, and also soil hardness of topsoil increased, but that of subsoil had not tendency. Average yield of sweet potato for 4years in the integrated improvement plot was 32.68ton/ha, which is increased by 59% in comparison to that of the control plot. Crop yield was in order of integrated improvement>phosphate>subsoiling>lime>compost>control plots. The soil properties of the topsoil which showed high correlation coefficient to sweet potato yield were bulk density, hardness and cation exchange capacity(CEC), and those of the subsoil were bulk density, soil moisture and CEC. Ratios of changes of soil properties except organic matter content showed high significancy to sweet potato yield. Soil physico-chemical properties of the 4th year without soil conditioners application were worse than those of 3rd year.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.4
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• pp.221-237
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• 2005

For developing the site-specific fertilizer management strategies of crop, it is essential to know the spatial variability of soil factors and to assess their influence on the variability of crop growth and yield. In 2002 and 2003 cropping seasons within-field spatial variability of rice growth and yield was examined in relation to spatial variation of soil properties in the· two paddy fields having each area of ca. $6,600m^2$ in Suwon, Korea. The fields were managed without fertilizer or with uniform application of N, P, and K fertilizer under direct-seeded and transplanted rice. Stable soil properties such as content of clay (Clay), total nitrogen (TN), organic mater (OM), silica (Si), cation exchange capacity (CEC), and rice growth and yield were measured in each grid of $10\times10m$. The two fields showed quite similar spatial variation in soil properties, showing the smallest coefficient of variation (CV) in Clay $(7.6\%)$ and the largest in Si $(21.4\%)$. The CV of plant growth parameters measured at panicle initiation (PIS) and heading stage (HD) ranged from 6 to $38\%$, and that of rice yield ranged from 11 to $21\%$. CEC, OM, TN, and available Si showed significant correlations with rice growth and yield. Multiple linear regression model with stepwise procedure selected independent variables of N fertilizer level, climate condition and soil properties, explaining as much as $76\%$ of yield variability, of which $21.6\%$ is ascribed to soil properties. Among the soil properties, the most important soil factors causing yield spatial variability was OM, followed by Si, TN, and CEC. Boundary line response of rice yield to soil properties was represented well by Mitcherich equation (negative exponential equation) that was used to quantify the influence of soil properties on rice yield, and then the Law of the Minimum was used to identify the soil limiting factor for each grid. This boundary line approach using five stable soil properties as limiting factor explained an average of about $50\%$ of the spatial yield variability. Although the determination coefficient was not very high, an advantage of the method was that it identified clearly which soil parameter was yield limiting factor and where it was distributed in the field.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.200-206
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• 1996

Experiment was conducted to get the information about physico-chemical properties of flue-cured tobacco on the degree of maturity cultivated in paddy-upland rotated field, and compared to upland ones. For the samples of this experiment, 3~4 leaves at each stalk position were harvested from the bottom of plants. Physico-chemical properties of cured leaves were determined from the samples collected at weekly intervals, and of obtained from 4 stalk positions. For the degree of maturity, harvested leaves were separated with visual characters into four classes such as immature, mature, ripe, and mellow. Regardless of stalk position, the order of shrinkage rate with length and width of leaves was mellow> immature> ripe> mature, and ripe leaves from paddy field showed higher shrinkage rate than those of upland. Nicotine and total nitrogen contents were decreased with the degree of maturity while reducing sugar content were showed a reverse tendency. Ripe leaves from paddy field had lower reducing sugar contents, comparing with upland tobacco. Filling capacity of cured leaves from paddy field was decreased with degree of maturity, but there was no difference between upland and paddy tobacco. Shatter index was increased in the oeder of immature > mellow > mature > ripe. Chemical components of cigarette smoke from paddy field tobacco were little higher in $CO_2$ total particulate matter and tar contents, while combustibility was little lower than that of upland tobacco. It was also evaluated that paddy field tobacco was unfavorable for the non-volatile organic and higher fatty acids contents comparing with upland tobacco.

• Cartoon and Animation Studies
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• s.13
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• pp.45-65
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• 2008

The animation industries of Korea and China shares the effort for transition from work-for-hire Industry Into creative industry. In spite of similar industry background and characteristics, and the aggressive government policy to support this industry transition at the same point of time, the current status of animation industries in Korea and China are showing very different statistics as of the end of 2007. The production amount of Chinese original animation has grown rapidly since 2004, which has made China the top class country in the world in original animation production amount, and more than 600 million audience of Chinese TV animation has firmly established the Chinese domestic animation market basis. On the other hand, despite the Korean government support, original animation production of Korea has been showing a slow and sluggish growth, and Korean animations are losing the domestic market basis with only 1% TV ratings due to unfavourable Korean TV stations' programming practices against Korean animations. This different status of animation Industries of two countries are the result of different government policies and the fallacy of Korean government. While the Chinese government has focused its industry policy on the facilitating the domestic market by establishing the stable broadcasting TV distribution and encouraging the animation production through organic cooperation between related government agencies, Korean government spent lots of effort into facilitating the development of original animation projects, without cooperative structure In the government, and without sincere consideration on the importance of establishment of domestic market consumer basis.

• Microbiology and Biotechnology Letters
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• v.43 no.2
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• pp.97-104
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• 2015

Vinegar is a widely used acidic seasoning and can be manufactured using various methods and bases, including cereals, wheat, and fruits. Most studies on vinegar have been conducted to evaluate its antioxidant activity. In the present study, fermented dark vinegar (FDV) produced from unpolished rice was examined for its antimicrobial activity, biochemical content, including the amounts of sugar, total soluble sugar, organic acid, and free amino acids, and pH and physiological activity. The antimicrobial efficiency of FDV was assessed using the paper disc-agar diffusion method. FDV exhibited strong antimicrobial activity against the pathogenic bacteria and yeast strains that were tested. In fact, the activity of FDV was shown to be higher than that of the commercial antibiotics carbenicillin (50 µg/ml) and tetracycline (50 µg/ml) against Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, Yersinia enterocolitica, and Lodderomyces elongisporus. The antioxidant activity of FDV and ascorbic acid was evaluated. Using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method, we found that FDV has the highest activity of the antioxidants. After spreading FDV onto tryptic soy broth and yeast extract-peptone-dextrose agar media, the microbial strains were isolated and characterized through physiological and biochemical analysis. Based on 16S ribosomal DNA sequence analysis, the isolated microorganisms exhibited a close similarity to Acetobacter papayae, Acetobacter pasteurianus, and Acetobacter peroxidans.

• Journal of Dairy Science and Biotechnology
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• v.37 no.4
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• pp.237-246
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• 2019

In this study, quality characteristics of yogurt supplemented with Angelica gigas Nakai leaf extract were examined. The pH of the yogurt ranged from 4.40 to 4.45 and the titratable acidity ranged from 0.96% to 0.98%. The viscosity tended to decrease with the addition of the Angelica gigas Nakai leaf extract, but did not affect stability during storage. In the range of 0.1% to 0.3%, lactic acid bacteria were present in the range of 1.9×10⁹ to 3.2×10⁹ CFU/mL. The decursin content in yogurt was quantitatively analyzed, depending on the addition of 0.1% to 0.3% of Angelica gigas Nakai leaf extract and was found to be 0.26 ㎍/g, 15.23 ㎍/g, and 23.57 ㎍/g respectively. Organic acid showed the highest generation of lactic acid. The antioxidant properties of yogurt were shown to increase with the addition of the Angelica gigas Nakai leaf extract. The sensory score of yogurt supplemented with 0.1% of the Angelica gigas Nakai leaf extract was highly valued, at a level similar to that of plain yogurt. Yogurt supplemented with 0.2% of the extract was rated above the normal score of 6.31 to 6.50. As shown by the results, the optimal concentration of Angelica gigas Nakai leaf extract for addition to yogurt was within 0.2%.

• Korean Journal of Environmental Agriculture
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• v.29 no.2
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• pp.197-205
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• 2010

This study was conducted to investigate the optimum conditions for efficient methane production through anaerobic digestion of pig waste slurry. The examined parameters were organic matter content of the pig slurry, the ratio of seed sludge to pig slurry, and stirring intensity of the digestion reactor. The effects of types of slurry produced from different purpose-based pigs fed with different feeds were also tested. The methane concentration in the produced biogas was 45% when the ratio of seed sludge to pig slurry was 50% and total solid (TS) concentration was 1%, and it increased in proportional to TS concentration increases from 3 to 7%. At 3 and 5% of TS concentration, increasing mixing velocity from 80 to 160 rpm resulted in higher biogas production amount. However, mixing amount of seed sludge did not cause any significant effect on biogas production. Overall, the most efficient biogas production was achieved at 3-5% TS concentration in combination with 50% seed sludge inoculation and mixing velocity at 120 rpm. Among pig slurry types, gestating sow waste slurry showed the highest biogas production probably due to higher the degradation rate than other types of pig waste slurry being affected by the feeds components.

• The Journal of Engineering Geology
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• v.14 no.3 s.40
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• pp.259-272
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• 2004

The purpose of this study is to investigate the effect of hydrochemical variation of groundwater on the gas tigtness in an unlined oil storage cavern. The groundwater chemistry is greatly influenced by the seawater mixing, the water curtain and the dissolution of grounting cements. The chemical composition of groundwater greatly varies ac-cording to both the location of monitoring wells and the sampling period. Most of groundwater shows alkaline pH and high electrical conductivity. The chemical types of groundwater show the dominant order as follows : Na-Cl type > Ca-Cl type > $Ca-HCO_3(CO_3)$ type. Thermodynamic equilibrium state between chemical composition of groundwater and major minerals indicates that carbonate minerals except clay minerals can be precipitated as a secondary mineral. It means that the secondary precipitates can not greatly exerts the clogging effect into fracture aperture in rock mass around oil storage cavern. The content of total organic carbon (TOC) shows a slightly increasing trend from initial stage to late stage. The $EpCO_2$ was computed so as to assess the gas contribution on the $CO_2$ in groundwater. The $EpCO_2$ of 0$\~$41.3 indicates that the contribution of oil gas on $CO_2$ pressure in groundwater system can be neglected.

• Korean Journal of Food Science and Technology
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• v.46 no.1
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• pp.19-24
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• 2014

This study was carried out to identify the volatile organic compounds (VOCs) in polyethylene terephthalate (PET) bottles and to determine the extent to which VOCs migrate into mineral water during the bottling process and storage. A greater amount of nonanal and decanal was generated from the PET bottles than from the PET preforms. Benzene, ethylbenzene, nonanal, and vinyl benzoate were identified from the PET bottles when the incubation temperature of the headspace solid-phase microextraction (HS-SPME) sampler was set to 60, 80, and $100^{\circ}C$. As the incubation temperature increased, the concentrations of nonanal, vinyl benzoate, and decanal increased significantly. When the high-density polyethylene (HDPE) PET bottle caps were extracted with dichloromethane, the level of Irgafos 168 was found to be $206{\pm}20.1\mu}g/g$. The concentration of 2,4-di-tert-butylphenol in water was $4.80{\pm}0.2{\mu}g/L$. Therefore, it is necessary to avoid exposing PET and HDPE resins to high temperatures during the manufacturing process and storage of bottled water.

• Korean Journal of Food Science and Technology
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• v.47 no.5
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• pp.599-607
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• 2015

Fermented-Rhus verniciflua (FRV) extract is increasingly used in fermented soy products, fermented vinegars, and certain alcoholic beverages. In this study, we investigated the effects of FRV extract on the physicochemical properties of doenjang (soybean paste). Addition of FRV extract to doenjang resulted in a 28.2-45.4% increase in the amino acid content and a 1.3- to 1.5-fold increase in the concentrations of glutamic acid, which imparts a savory flavor to doenjang. The concentration of biogenic amine (BA) of the sample containing the extract was 5.3-52.6% lower than that of the control. The major components of BA included tyramine (55.1-74.6%), followed by putrescine, spermidine, tryptamine, and cadaverine, in decreasing concentrations. The organic acid concentration of the sample containing the extract was 1.2-1.3-fold higher than that of the control. The total free sugar concentration was 163.4 mg/100 g in the control and 206.6-276.8 mg/100 g in the supplemented sample, showing a 1.3- to 1.9-fold increase as the addition of the extract.