• Korean Journal of Soil Science and Fertilizer
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• v.49 no.4
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• pp.310-317
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• 2016

This study aimed to evaluate the nutrient load balance from rice paddy fields with different topographies, alluvial plain and local valley. Continuous monitoring from May to September, 2013 was conducted for water quantification and qualification from alluvial plain in Yeoju region (32 ha) and local valley in Jincheon region (24 ha). The discharge rates of T-N from the alluvial plain were 57.2, 5.84, 22.7, and $5.20kg\;ha^{-1}$ for irrigation, precipitation, drainage, and percolation, respectively. In case of local valley, T-N loads were 34.6, 4.73, 21.1, and $4.15kg\;ha^{-1}$ for irrigation, precipitation, drainage, and percolation, respectively. In contrary, the T-P loads from the alluvial plain were 2.23, 2.22, 2.54, and $0.41kg\;ha^{-1}$ for irrigation, precipitation, drainage, and percolation, respectively. In case of local valley, T-P loads were 1.44, 1.57, 1.82, and $0.34kg\;ha^{-1}$ for irrigation, precipitation, drainage, and percolation, respectively. The nutrient contents in drainage water were influenced by the amount of waters, rainfall, and surface drainage water. The Pearson correlation analysis showed that rainfall was significantly correlated with nutrient loads from July to August due to the amount of runoff in local valley paddy field, and irrigation was related with nutrient loads of drainage from July to August. This study showed that paddy rice farming in alluvial plain and local valley might be beneficial to water quality protection.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.20 no.1
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• pp.64-81
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• 1994

O/W emulsions with mixed nonionic surfactants(polyoxyethylene(20)sorbitan monostearate/sorbitan sesquioleate), liquid paraffin, water prepared by direct inversion emulisification method and continuous inversion emulsification Method. The one-step, two-step and three-step phase inversion emulsification method were used in experiments. Effect of added water on droplet size of final O/W emulsions which is prepared by phase inversion emulsification method were investigated. In direct inversion emulsification method(two-step emulsification method), fine and homogeneous droplets of OIW emulsions were formed after phase inversion steps i.e. ,W/O - (W/O) If double emulsion - O/W emulsion. In continuous inversion emulsification method(three-step emulsification method), fine and homogeneous O/W emulsion were formed after phase inversion steps i.e., W/O - pseudomicroemulsion - O/W. By latter method, more Fine and homogenuous droplets were formed than former method. 10-10, 8 HLB region of mixed non-ionic surfactants could produce most fine droplets. This HLB region had maximum values of solubilization water and This HLB value of mixed nonionic surfactants produced fine and homogenuous droplets.

• Preventive Nutrition and Food Science
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• v.19 no.3
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• pp.145-155
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• 2014

Vascular dementia is characterized by white matter lesions involving the demyelination and activation of astrocytes and microglia. In a previous study, we showed that the supernatant of a laboratory-scale, hot water extract of ground whole wheat (TALE) attenuated white matter injury and astrocytic activation in a rat model of bilateral common carotid artery occlusion (BCCAO). In the present study, we made several modifications to the hot water extraction process to remove starch and enable large-scale production. We used wheat bran (WB), which contains less starch, instead of ground whole wheat. In addition, we removed starch granules with a decanter before hot water extraction. The final product, wheat bran extract (WBE), contained 2.42% arabinose, a surrogate marker of arabinoxylan, which is an active constituent of WBE. Supplementation of the rat model of BCCAO with WBE (400 mg/kg/day) for 33 days attenuated white matter injury, which was assessed by Luxol Fast Blue staining, in the corpus callosum (cc) and optic tract (opt) regions. Attenuation of white matter injury in the opt region was accompanied by improvement of the pupillary light reflex. Immunochemical staining revealed that supplementation with WBE reduced astrocytic activation in the cc and opt regions and reduced microglial activation in the opt region. These findings indicate that supplementation with WBE is effective at attenuating white matter injury accompanied by the inhibition of astrocytic and microglial activation. Therefore, extracts from WB, a cheap by-product of wheat milling, can be developed as a nutraceutical to prevent vascular dementia, a disease for which there is no approved pharmaceutical treatment.

• Analytical Science and Technology
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• v.10 no.6
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• pp.418-426
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• 1997

Dewatered digested sewage sludge were heated with microwave and their drying characteristics were investigated on the effect of their surface area, shape, diameter and thickness. The drying characteristics of identical samples in a conventional drying oven were studied. In conventional drying, constant rate period was not found and moisture was evaporated with capillary action. Moisture in the sludge was a bound water and free water was not exist. In microwave drying, the falling rate period was divided into two zones. In falling rate drying period, moisture movement occured by diffusion. The evaporation surface area was a significant variable, the greater heating surface area promoted water removal rate over wide region of water content. Drying rate was slow and constant rate drying period was found in wide moisture content region with increasing diameter. Drying characteristics appeared differently in various shape. In microwave heating, first of all temperature of sludge center was increased and was the highest. Temperature in the constant rate drying period was remained constantly at $80{\sim}100^{\circ}C$.

• Journal of Korea Water Resources Association
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• v.31 no.6
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• pp.807-819
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• 1998

The relationships of El Nino and La Nina with both temperature and precipitation in South Korea is studied. Monthly temperature and precipitation are analyzed using harmonic analysis to identify region, magnitude and season that have responses associated with El Nino and La Nina. The first harmonic is extracted from a 24 month El Nino and La Nina composite at each station. The regions are identified by the similarity in the phase of the harmonic vectors. The responses of precipitation to El Nino and La Nina are found in the all regions. However, the response of precipitation to El Nino and La Nina is identified only in the southern region. In addition, statistical significance for response periods is investigated through cross correlation analysis. Once an El Nino and a La Nina event set in, the results of this analysis can provide an efficient information for the management of water resources, agriculture and environment.

• Journal of Environmental Science International
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• v.24 no.6
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• pp.731-741
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• 2015

The objectives of study were to evaluate fish species compositions of trophic guilds and tolerance guilds and apply ecological fish assessment (EFA) models to Bekjae Weir, Keum-River Watershed. The EFA models were Stream Index of Biological Integrity (SIBI) used frequently for running water and Lentic Ecosystem Health Assessment (LEHA) used for assessments of stagnant water. The region of Bekjae Weir as a "four major river project" was originally a lotic ecosystem before the weir construction (2010, $B_{WC}$) but became more like lentic-lotic hybrid system after the construction (2011, $A_{WC}$). In the analysis of species composition and ecological bioindicator (fish), fish species with a preference of running water showed significant decreases (p < 0.05), whereas the species with a preference of stagnant water showed significant increases (p < 0.05). After the weir construction, relative abundances of tolerant species increased, and the proportion of insectivores decreased. This phenomenon indicated the changes of biotic compositions in the system by the weir construction. Applications of SIBI and LEHA models to the system showed that the two model values decreased at the same time after the weir construction ($A_{WC}$), and the region became more like lentic-lotic hybrid system, indicating the degradation of ecosystem health. The model values of SIBI were 19 and 16, respectively, in the BWC and AWC, and the health conditions were both "C-rank". In the mean time, the LEHA model analysis showed that the values was 28 in the BWC and 24 in the AWC, thus the health was turned to be "B-Rank" in the BWC and "C-Rank" in the AWC. indicating a degradation of ecological heath after the weir construction.

• Water Engineering Research
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• v.7 no.1
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• pp.1-8
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• 2006

Recently, the population growth and agricultural development are rapidly undergoing in the South-West Texas. The junction of three river basins such as Lavaca river basin, Colorado-Lavaca Coastal basin and Lavaca-Guadalupe Coastal basin, are interesting for non-point and point source pollutant modeling: Especially, the 2 basins are an intensively agricultural region (Colorado-Lavaca Coastal/Lavaca-Guadalupe Coastal basins) and several cities are rapidly extended. In case of the Lavaca river basin, there are many range land. Several habitat types wide-spread over three relatively larger basins and five wastewater discharge regions are located in there. There are different hazardous substances which have been released. Total nutrient loads are composed of land surface load and river load as Non-point source and discharge from wastewater facilities as point source. In 3 basins region, where point and non-point sources of poll Jtion may be a big concern, because increasing fertilizers and pesticides use and population cause. This project objective seeks to how to assess and control the accumulation of non-point and point source and discuss the main impacts of agriculture and environmental concern as non-point source with water quality related to pesticides, fertilizer, and nutrients and as point source with wasterwater discharge from cities. The GIS technique has been developed to aid in the point and non-point source analysis of impacts to natural resource within watershed. This project shows the losses in $kg/km^2/year$ of BOD (Biological Oxygen Demand), TN (Total Nitrogen) and TP (Total Phosphorus) in the runoff from the surface of 3 basins. In the next paper, sediment contamination will show how to evaluate in Estuarine habitats of these downstream.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.329-329
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• 2022

Accurate characterization of terrestrial precipitation variation from high spatial resolution satellite sensors is beneficial for urban hydrology and microscale agriculture modeling, as well as natural disasters (e.g., urban flooding) early warning. However, the widely-used top-down approach for precipitation retrieval from microwave satellites is limited in several hydrological and agricultural applications due to their coarse spatial resolution. In this research, we aim to apply a novel bottom-up method, the parameterized SM2RAIN, where precipitation can be estimated from soil moisture signals based on an inversion of water balance model, to generate high spatial resolution terrestrial precipitation estimates at 0.01º grid (roughly 1-km) from the C-band SAR Sentinel-1. This product was then tested against a common reanalysis-based precipitation data and a domestic rain gauge network from the Korean Meteorological Administration (KMA) over central South Korea, since a clear difference between climatic types (coasts and mainlands) and land covers (croplands and mixed forests) was reported in this area. The results showed that seasonal precipitation variability strongly affected the SM2RAIN performances, and the product derived from separated parameters (rainy and non-rainy seasons) outperformed that estimated considering the entire year. In addition, the product retrieved over the mainland mixed forest region showed slightly superior performance compared to that over the coastal cropland region, suggesting that the 6-day time resolution of S1 data is suitable for capturing the stable precipitation pattern in mainland mixed forests rather than the highly variable precipitation pattern in coastal croplands. Future studies suggest comparing this product to the traditional top-down products, as well as evaluating their integration for enhancing high spatial resolution precipitation over entire South Korea.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.9
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• pp.614-623
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• 2014

Customers water quality complaints by foreign substance in local water service can be able to call the main cause bring the distrust for tap water and inhibiting the rate of drinking water. In this study, foreign substances were collected in the target region. Foreign objects were subjected to qualitative and quantitative analysis of compounds and elements components to reveal the cause of detection. Also, resolve the complaints by foreign substance and improve the reliability for tap water providing high quality water supply scheme. Collected substances at the water quality complaint area were included in inorganic compounds due to internal corrosion and aging pipeline, as well as organic compounds containing a large amount of carbon (C) and oxygen (O) component. To decide and reduce for foreign substance, objective assessment of pipe condition in target area was required.

• Journal of Soil and Groundwater Environment
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• v.25 no.1
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• pp.84-94
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• 2020

Jeju Island is seeking reliable ways to secure alternative water resources using rainwater in order to conserve and manage its groundwater as sustainable water resources. The purpose of this study is to investigate the rainwater storage capability of small-size storage facilities installed at farmhouses in Uigwi and Wimi of Namwon-eup region. The rainwater outflows from the storage facilities in rain events were analyzed. The appropriate size of rainwater utilizing facilities are suggested to be about 5,800 ㎥ in Uigwi area and 4,900 ㎥ in Wimi area based on the calculation from the rainfall frequency and runoff amounts. If those facilities are put into operation in Uigwi and Wimi area, it is estimated approximately 32.3 and 11.5% of total agricultural water can be supplied by the facilities. Wimi area showed low rainwater usage because of less number of facilities relative to the size of farm areas and less intensive underground water usage. It is analyzed that more than 55% of agricultural water can be supplied by rainwater if 70 facilities without the rainwater facilities are connected to the rainwater utilizing facilities.