• Korean Journal of Soil Science and Fertilizer
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• v.50 no.2
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• pp.81-92
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• 2017

Recently, agricultural lands have decreased sharply, which was caused by huge housing site, urbanization, land consolidation, and road construction etc. In particular, Yangju city near Seoul city has the most severe land use change in Korea. Therefore, we analyzed changes of land use, soil properties, and soil information in order to provide the basic soil information and soil management practices in this city. The area of crop cultivated land in Korea (2015) reduced by 12,090 ha compared to ones from the previous year (2014). The paddy field decreased by 25,421 ha but, upland field increased by 13,331 ha. One of the reasons for the reduction of the paddy field was converting paddy field to upland (20,916 ha) > others (3,056) > building (2,571) > public facilities (847) > idle land (217). But, reasons for increase of upland field were switching paddy to upland (20,916 ha) > land developed (634). The main reason of converting paddy field to upland was changing from rice to more profitable speciality crops or pulses. The cropland area (paddy fields, upland, orchard) of Yangju city reduced by 1,412 ha (2015/2014). The ratio of cropland area in each city reduced by 22.9% dramatically compared 2015 to 1999. The paddy fields located in alluvial plains in Yangju city were changed into upland or green house. The drainage classes of soil have been deteriorated because the flows of water were intercepted by road construction and other disturbance to water flows. In particular, paddy fields have been changed to not only upland, orchard, greenhouse cultivation but also to fallow and soil dressing on paddy in Yangju city. To analyze result of soil survey of Yangju city, 858 soil codes (soil phases) were used and the area was 105.17ha. The number of soil series increased from 60 to 65, and that of soil phase increased from 105 to 124. The largest increased area was Noegog soil series. 125.7ha of Neogog soil series was incorporated from the existing Sachon, Yecheon and Eungog soil series. The soil suitability class of paddy field in Ogjung huge housing site of Yangju city was the 4th grade for 32.6% of the area. The soil suitability classes of upland were 2nd and 3rd grade for 72.4% of the area. Farm land with high quality should be conserved by related law.

• Korean journal of food and cookery science
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• v.11 no.5
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• pp.487-493
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• 1995

The material ratio for preparation of Kimchi in Seoul and Chung Cheong area and the pH, total acidity and NaCl concentration of properly fermented Kimchi were investigated. The kinds of Kimch prepared for the Winter were cabbage Kimchi, Kakdugi, Chonggak Kimchi, Nabak Kimchi, Dongchimi, Bossam Kimchi, and Paek Kimchi. The materials used for chbbage Kimchi were 20 to 25 of ingredients including salted fish and dhellfish. The material ratio of Kimchi was 71.9% of cabbage, 11％ of radish, 2.3-2.6% of green onion, 1.3-1.6% of garlic, 2.7-3.2% of powdered red pepper and 3.9-4.2% of salted fish. The kinds of Kimchi for Spring were cabbage Kimchi, Kakdugi, Chonggak Kimchi, Yulmu Kimchi and cucumber Kimchi. The amount of salted fish and shellfish used were decreased in Spring while vegetables of the season increased. The properly fermented cabbage Kimchi were measured of pH 4.2-4.5 and total acidity of 0.5-0.8%. The favorite concentrations of NaCl were found to be 2.3-2.7% in Winter Kimchi and 1.8-2.4% in Spring Kimchi and in watering Kimchi was shown low as 1.3-1.7%.

• Economic and Environmental Geology
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• v.37 no.6 s.169
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• pp.647-655
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• 2004

To identify the influential factors and their relative significance on spatial distribution of $NO_3-N$ in urban ground water, spatial analysis was conducted using GIS and statistical approaches in the Seongnae-Koduk watersheds, where rapid urbanization has been proceeded. Several factors were considered including land-use type, distance to sewage lines, the ratio of impervious surface, and the ratio of green area. The spatial distribution of $NO_3-N$ in the land-use types shows differences between urban and crop field possibly due to the sewage networks in urban areas and the agrochemical uses in crop field. Nitrate concentrations in ground water were decreased with the distance to sewage lines to approximately 60-75 m. Concentrations of nitrate and distances to sewage lines showed negative correlation, indicating that the nitrate contamination was induced from the sewage system and specially significant in urban areas. The negative correlation of the ratio of impervious surface to the nitrate concentration in urban areas also suggested that the source materials of nitrate are introduced from the surface. Consequently, in areas of urbanization processes, systematic management of past-and-present land-use types and sewage systems are the most significant factors in preventing ground water from nitrate contamination.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.664-672
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• 2012

As an artificial light source, light-emitting diode (LED) with a short wavelength range can be used in closed-type plant production systems. Among various wavelength ranges in visible light, individual light spectra induce distinguishing influences on plant growth and development. In this study, we determined the effects of monochromatic LEDs on leaf shape index, growth and the accumulation of phytochemicals in a red leaf lettuce (Lactuca sativa L. 'Sunmang') and a green leaf lettuce (Lactuca sativa L. 'Grand rapid TBR'). Lettuce seedlings grown under normal growing conditions ($20^{\circ}C$, fluorescent lamp + high pressure sodium lamp, $130{\pm}5{\mu}mmol{\cdot}m^{-2}{\cdot}s^{-1}$, 12 hours photoperiod) for 18 days were transferred into incubators at $20^{\circ}C$ equipped with various monochromatic LEDs (blue LED, 456 nm; green LED, 518 nm; red LED, 654 nm; white LED, 456 nm + 558 nm) under the same light intensity and photoperiod ($130{\pm}7{\mu}mmol{\cdot}m^{-2}{\cdot}s^{-1}$, 12 hours photoperiod). Leaf length, leaf width, leaf area, fresh and dry weights of shoots and roots, shoot/root ratio, SPAD value, total phenolic concentration, antioxidant capacity, and the expression of a key gene involved in the biosynthesis of phenolic compounds, phenylalanine ammonia-lyase (PAL), were measured at 9 and 23 days after transplanting. The leaf shape indexes of both lettuce cultivars subjected to blue or white LEDs were similar with those of control during whole growth stage. However, red and green LEDs induced significantly higher leaf shape index than the other treatments. The green LED had a negative impact on the lettuce growth. Most of growth characteristics such as fresh and dry weights of shoots and leaf area were the highest in both cultivars subjected to red LED treatment. In case of red leaf lettuce plants, shoot fresh weight under red LED was 3.8 times higher than that under green LED at 23 days after transplanting. In contrast, the accumulation of chlorophyll, phenolics including antioxidants in lettuce plants showed an opposite trend compared with growth. SPAD value, total phenolic concentration, and antioxidant capacity of lettuce grown under blue LED were significantly higher than those under other LED treatments. In addition, PAL gene was remarkably activated by blue LED at 9 days after transplanting. Thus, this study suggested that the light quality using LEDs is a crucial factor for morphology, growth, and phytochemicals of two lettuce cultivars.

• Journal of Nutrition and Health
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• v.32 no.3
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• pp.307-317
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• 1999

To assess the food intake and diet quality of Koreans living in rural areas with discriminative environment, this dietary survey was conducted with 553 subjects living in five different rural areas using a one-day, 24-hour recall method. The average weight of total food intake was 1066g, with vegetable and animal food comprising 83.75 and 16.3% of total food intake, respectively. The average daily food intakes of residents in the five areas were 985g, 1005g, 1028g, 1318g, and 964g, and were significantly different(p<0.001). Residents of Ulju consumed the largest amount of food, 1318g. The total number of food items consumed was 336. The foods consumed in largest amounts were rice(223g), Korean cabbage-Kimch'i(111g), and soybean curd(41g). The foods consumed most frequently were rice, Korean cabbage-Kimchi, green onion and garlic. When investigating the consumption pattern of the major five food groups, only 5% of subjects consumed all five groups. The groups most frequently missing were dairy products and fruits. The average number of foods consumed per day was 16.8, but differed significantly by area(p<0.001). The number of major food groups (DDS, dietary diversity score) and that of food items(DVS, dietary variety score) correlated positively with NAR (nutrient adequacy ratio) and MAR (mean adequacy ratio). People with a DDS of above 4 or DVS of above 20 met two-thirds of the recommended dietary allowance for most nutrients. When assessing the dietary quality of subjects using DDS and DVS, many people appeared not to have a desirable food intake. dietary guidelines should be made considering the nutritional characteristics of different areas to improve the health of people living in those areas.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.3
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• pp.33-48
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• 2009

A palustrine wetland is a type of a wetland that prevails in Korea as well as an ecosystem that provides various ecological functions and has affluent biodiversity. This study was conducted to understand the characteristics of vegetation in a palustrine wetland by analyzing a life form and naturalized plants, in order to present the maintenance and utilization plan of a small wetland. A total of 249 taxa including 76 families, 188 generics, 209 species, 38 varieties and 2 forma were found at six investigated wetlands. As a result of the appearance ratio analysis, Therophytes (37.8%) with 94 taxa and Hemicryptophytes (31.3%) with 78 taxa were in order of life form, and Gramineae (14.1 %) with 35 taxa and Compositae (11.2 %) with 28 taxa were in order of family level. These were deemed representative vegetation in a palustrine wetland. Equosetum arvense, Phragmites communis, Commelina communis, Persicaria thunbergii, Arenaria serpyllifolia, Stellaria media, Erigeron annuus, Erigeron canadensis and Artemisia princeps var, orientalis were found continuously for a period of investigation in all sites. Equosetum arvense, Phragmites communis and Persicaria thunbergii were species with high appearance frequency. Especially, Persicaria thunbergii was construed high in a cover ratio in May as it develop first among Hydrophytes and form a canopy sooner than anything else. We found that a degree of naturalization and an urbanization index appear comparatively high in Yeongok-ri, Cheonan, Gangjang-ri, Asan and Yodang-ri, Hwasung, which is construed due to artificial interference, such as fanning, fishing, swimming and green-tour program. These results would be used to utilize in restoring a deserted and damaged wetland and to provide fundamental data in creating a wetland as follows.

• Korean Journal of Materials Research
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• v.3 no.3
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• pp.245-252
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• 1993

We investigated the changes of (U, Ce)$O_2$ powder characteristics with $CeO_2$ contents and ball-milling time and then studied on the sintering properties with those (U, Ce)$O_2$ powder characteristics. From the results of this study, it was concluded that the longer ball-milling time of (U, Ce)$O_2$ powder was, the finer its particle size was. Green and sintered densities were decreased with $CeO_2$ contensts increase. And also $CeO_2$ was recongized deteriorating oxide on the $UO_2$ sintering. In case of the lOwt. % $CeO_2$ contents, (U, Ce)$O_2$ sintered pellet which was made of ball-milled powder for 4 hours had few pores and its pores got near to the sphere. And its sintered density had the highest. Because its powder had higher surface area and its packing ratio was appropriated much better than others.

• Journal of the Korean earth science society
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• v.36 no.4
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• pp.330-340
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• 2015

For this study, we developed an algorithm to estimate the total amount of clouds using sky image data from the Skyviewer equipped with CCD camera. Total cloud amount is estimated by removing mask areas of RGB (Red Green Blue) images, classifying images according to frequency distribution of GBR (Green Blue Ratio), and extracting cloud pixels from them by deciding RBR (Red Blue Ratio) threshold. Total cloud amount is also estimated by validity checks after removing sunlight area from those classified cloud pixels. In order to verify the accuracy of the algorithm that estimates total cloud amount, the research analyzed Bias, RMSE, and correlation coefficient compared to records of total cloud amount earned by human observation from the Gangwon Regional Meteorological Administration, which is in the closest vicinity of the observation site. The cases are selected four daily data from 0800 LST to 1700 LST for each season. The results of analysis showed that the Bias in total cloud amount estimated by the Skyviewer was an average of -0.8 tenth, and the RMSE was 1.6 tenths, indicating the difference in total cloud amount within 2 tenths. Also, correlation coefficient was very high, marking an average of over 0.91 in all cases, despite the distance between the two observation sites (about 4 km).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.3
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• pp.333-342
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• 2022

Due to climate change, increased heavy rainfalls result in flood damage every year. To investigate the storm-runoff reduction effects of Low Impact Development (LID), this study performed runoff analyses using the U.S. Environmental Protection Agency (EPA) Storm Water Management Model (SWMM) for past and future representative storm events of the Yongdu Rainwater Pumping Station basin. As a result, the infiltration loss for representative future rainfalls increased by 3.17 %, and the surface runoff and peak runoff rate increased significantly by 32.50 %, and 128.77 %, respectively. To reduce the increased surface runoff and peak runoff rates, this study investigated the applicability of LID approaches, including a permeable pavement, green roof, and rain garden, by adjusting the LID parameters and the ratio of installation area. We identified the ranges of LID parameters that decreased peak runoff rate and surface runoff, and increased infiltration. In addition, when the application ratio of permeable pavement, green roof, and rain garden was 2:1:3, best performance was attained, leading to a reduction of peak runoff of 26.85 %, infiltration loss 12.01 %, surface runoff 15.11 %, and storage 509.47 %. Based on analyzing the effect of storm runoff reductions for various return periods, it was found that as the return period increased, the proportion of peak runoff and surface runoff increased and the proportion of infiltration loss and storage decreased.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.3
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• pp.26-38
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• 2006

For both a healthy environment and sustainable development, we frame a habitat assessment method, concerning biodiversity and physical characteristics. With the method, we set up and extract conservation areas from Peace Valley Resort Development Areas which can function as habitats. Absolute and relative assessment items which are the size of area, habitation of species with conservation value, distribution of communities, functions of habitats, ratio of non-native plants, connectivity of habitats, vegetation layers of forests and age of forests, and water systems are considered on newly extracted conservation areas, and the habitat value assessment was calculated on the items in a 3-point scale. By comparing and examining 3 existing proposals for extracted conservation areas, we assess existing proposals, make an alternative proposal, and try to verify the possibility of applicability to extracted conservation areas. Proposal A and C must not be adopted since almost all conservation areas would be developed in the proposals. Proposal B, consisting of 53% development areas and 47% non-development areas, does not have enough development areas, so high density building arrangements should be encouraged in order to preserve conservation areas. Therefore, proposal B would be the best in ecological terms among the 3 proposals, if 3 conditions are considered : 1) new extracted conservation areas should be conserved; 2) 10~15m wide green-zones on both sides of the water system, which can play a role as ecological corridors, should be considered in development areas; 3) building arrangement should not interrupt the ecological corridors.