• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.1081-1085
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• 2012

This study was performed in order to determine the processing conditions (pre-drying at room temperature for 0 or 30 min, frying at $160^{\circ}C$ for 1 min or at $180^{\circ}C$ for 40 sec, and soaking for 0~24 h) of Sasambeong recorded in the "Sumunsasul". The Sasambeong was evaluated for crude lipid content, hardness, Hunter's color values, and sensory characteristics. After pre-drying at room temperature for 30 min, the crude lipid contents and hardness of Sasambeong were significantly increased. In addition, the crude lipid content and hardness of Sasambeong did not differ significantly according to the frying conditions. After pre-drying, the sensory characteristics of Sasambeong showed more improvement. The crude lipid content, hardness, Hunter's color values, and sensory characteristics of Sasambeong, which were prepared according to different soaking times (0, 6, 12, or 24 hr) were investigated. As soaking time increased, the crude lipid content and hardness of Sasambeong decreased with a range of 25.43~24.31% and 525.90~388.98 g, respectively. The sensory characteristics of Sasambeong showed no significant difference according to the soaking time. Overall, we think that the best processing conditions of Sasambeong were pre-drying at room temperature for 30 min and then frying at $160^{\circ}C$ for 1 min.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.8
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• pp.572-577
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• 2011

The unit load has simply been used to estimate total pollutant loading from non-point sources, however, it does not count on the variable pollutant loading according to land use characteristics and rainfall intensity. Since pollutant emission from the watershed is strongly dependent on the rainfall intensity, it is necessary to find out the relationship between pollutant loading and rainfall intensity. The objective of this study is to develop simple and easy method to compute non-point source pollution loads with consideration of rainfall intensity. Two non-point source removal facility at Gyeongan-dong (Gwangju-si) and Mohyeon-myeon (Yongin-si), Gyeonggi-do was selected to monitor total rainfall, rainfall intensity, runoff characteristics and water quality from June to November, 2010. Most of Event Mean Concentrations (EMC) of measured water quality data were higher in Gyeongan which has urban land use than in Mohyeon which has rural land use. For the case of TP (Total Phosphorus), Mohyeon has higher values by the influence of larger chemical uses such as fertilizer. The relationship between non-point source pollution load and rainfall intensity is perfectly well explained by cubic regression with 0.33~0.81 coefficients of determination($R^2$). It is expected that the pollution loading function based on the long-term monitoring would be very useful with good accuracy in computing non-point source pollution load, where a rainfall intensity is highly variable.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.413-413
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• 2019

하천과 호수에서 남조류의 이상 과잉증식 문제(이하 녹조문제)는 담수생태계의 생물다양성을 감소시키며, 음용수의 이취미 원인물질을 발생시켜 물 이용에 장해가 된다. 또한 독소를 생산하는 유해남조류가 대량 증식할 경우에는 가축이나 인간의 건강에 치명적 해를 끼치기도 한다. 그 동안 국내에서 녹조문제는 댐 저수지와 하구호와 같은 정체수역에서 간헐적으로 문제를 일으켰으나, 4대강사업(2010-2011)으로 16개의 보가 설치된 이후 낙동강, 금강, 영산강 등 대하천에서도 광범위하게 발생되고 있어 중요한 사회적 환경적 이슈로 대두되었다. 한편, 대하천에 설치된 보 구간에서 빈번히 발생하는 녹조현상의 원인에 대해서는 전 지구적 기온상승에 따른 기후변화의 영향이라는 주장과 유역으로부터 영양염류의 과도한 유입, 가뭄에 따른 유량감소, 보 설치에 따른 체류시간 증가 등 다양한 의견이 제시되고 있으나, 대상 유역과 수체의 특성에 따라 녹조 발생의 원인이 상이하거나 또는 다양한 요인이 복합적으로 작용하기 때문에 보편적 해석(universal interpretation)이 어려운 것이 현실이다. 따라서 각 수계별, 보별 녹조현상에 대한 정확한 원인분석과 효과적인 대책 마련을 위해서는 집중된 실험자료와 데이터마이닝 기법에 근거로 한 보다 과학적이고 객관적인 접근이 이루어져야 한다. 본 연구에서는 2012년 보 설치 이후 남조류에 의한 녹조현상이 빈번히 발생하고 있는 낙동강 4개보(강정고령보, 달성보, 합천창녕보, 창녕함안보)를 대상으로 집중적인 현장조사와 실험분석을 수행하고, 수집된 기상, 수문, 수질, 조류 자료에 대해 통계분석과 다양한 데이터모델링 기법을 적용하여 보별 남조류 우점 환경조건과 이를 제어하기 위한 주요 조절변수를 규명하는데 있다. 연구대상 보 별 수질과 식물플랑크톤의 정성 및 정량 실험은 2017년 5월부터 2018년 11월까지 2년에 걸쳐 실시하였으며, 남조류 세포수 밀도와 환경요인과의 상관성 분석을 실시하고, 단계적 다중회귀모델(Step-wise Multiple Linear Regressions, SMLR), 랜덤포레스트(Random Forests, RF) 모델과 재귀적 변수 제거 기법(Recursive Feature Elimination using Random Forest, RFE-RF)을 이용한 변수중요도 평가, 의사결정나무(Decision Tree, DT), 주성분분석(Principal Component Analysis, PCA) 기법 등 다양한 모수적 및 비모수적 데이터마이닝 결과를 바탕으로 각 보별 남 조류 우점 환경요인을 종합적으로 해석하였다.

• Journal of Wetlands Research
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• v.17 no.1
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• pp.62-74
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• 2015

Urban areas are variously under threat including deterioration of ecological functions. Many pond wetland types have been created as part of an effort to improve and restore this urban environment. This study was arranged to examine improvement plans of wetlands in urban areas by analyzing semi-natural wetlands in farm areas. As for environment for water quality, it suggested the inflow of natural water neighboring rivers or the direct inflow of rain as the improvement plans. The result which analyzed soil pH, OM, and T-N content of the soil environment mentioned that urban areas supplied artificial sluices, removed apoptotic bodies, and used artificial soil and waterproofing materials and use of natural materials in design and construction, the sluice state of the natural form, and negligence of autumn plants were suggested as the improvement plans. Florae appeared in the subject sites of the study have found that there are 35 families 69 species in urban areas and 53 families 142 species in rural areas. As the average has found that there are 18.5 families 29.3 species in 4 urban areas and 26.3 families 53.5 species in 4 rural areas, the big difference between them was analyzed. As the cause has found that there are differences in yearly plants in farming areas when compared to urban areas, creation of various basic environments including soil and water quality was suggested to make yearly plants settle down widely. Naturalized plants have found that there are no big differences between urban areas and rural areas. However, the average of the naturalized ratio in urban areas is 17.4% as the naturalized plants are about 1/4 of the appeared plants. As it was analyzed to be higher than 7.7%, the average of the naturalized ratio in farming areas as the big difference, creation of various inhabiting environments was suggested to make more yearly plants appear like the analyzed result of the life type. Consideration of placement, materials, and inhabiting environments was suggested to make creation of wetlands well appreciated to improve functions of wetlands in urban areas. It is expected that the above results of the study will be utilized in creation and improvement of the pond wetlands which can play a huge role in increase and improvement of biological diversity in urban areas.

• Journal of Environmental Impact Assessment
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• v.24 no.3
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• pp.287-299
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• 2015

If the Nakdong River estuary is to be sustainable, land use management practices need to consider bird habitat requirements, especially given that the area serves as an important migratory bird sanctuary. In this study, bird habitats found in the Nakdong River estuary were classified into 11 different types including Phragmites australiss, mud flat, farmland, open surface in freshwater, sand bar, riparian forest, Scirpus planiculmis, waterway, construction, grasslands, and open surface in sea or brackish water. Taking into consideration the regional characteristics, habitat properties, and landscape indices, a total of 12 study sites were analyzed. Mud flat, construction, farmland, and P. australis account for 80% of the total land area. The high area ratio of construction and farmland to other types of habitat revealed a high amount of historical human activity and intervention in the area. Both patch numbers as well as patch density were high in West Nakdong River, Samrak Waterfront, Maekdo River, and Daejeo Floodgate, with these areas showing the greatest fragmentation as well. Total numbers of species and individuals had a positive correlation with the area and the number of habitat types. Findings suggest that protecting the habitat area, especially in S. planiculmis, is the most important factor for bird habitat management and that future development could result in habitat loss, having a profoundly adverse impact on bird populations. Therefore, it is important that the total area should be carefully protected by land use regulations in order to ensure that the Nakdong River estuary maintains its functional integrity as a migratory bird sanctuary.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.4
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• pp.262-268
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• 2007

To characterize morphological classification of the basins, four major basin characteristics of the unit basins, including sinuosity, ratio of forest, ratio of flat area, and tributary existence were selected for cluster analysis. The analysis was carried out using soil map, topographic map, water course map, and basin map of the fifty unit basins in the Yeongsangang Basin. The unit basins could be categorized to five basin groups. The fitness by the Mantel test showed good fit of which r was 0.830. These grouping based on comprehensive soil and topographic characteristics provides best management practices, water quality management according to pollutants, increased water related model application and reasonable availability of water management. For agricultural management of water resources and conservation of water quality from agricultural non-point pollutants, therefore, comprehensive systematic classification of soil characteristics on unit basin might be an useful tool.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.985-989
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• 2013

This study was performed to determine the best conditions for preparing Toranbyung. We examined different boiling periods (0~20 min) and types of Gomyeong (pine nut, soy, black sesame, and chestnut powder), as recorded in "Sumunsasul". The boiled taros were evaluated for proximate composition, free sugar contents, and Hunter's color values. In addition, the sensory characteristics of Toranbyung boiled for different periods and prepared using different types of Gomyeong were investigated. The moisture, protein, fat, and ash contents of taro decreased by 83.42~84.61%, 1.25~1.31%, 0.08~0.11%, and 0.62~0.81%, respectively, as the length of boiling time increased. Fructose, glucose, and sucrose, the major free sugars found in taro, decreased by 0.17~0.33%, 0.16~0.29%, and 0.26~0.38%, respectively, as the length of boiling time increased. Sensory evaluation indicated no significant difference in the flavor and taste of Toranbyung boiled for different periods of time. However, Toranbyung boiled for 10 min was significantly better and was found to be the most acceptable among all the samples. Furthermore, sensory evaluation of Toranbyung prepared with different types of Gomyeong indicated that the Toranbyung prepared with soy powder was favored over Toranbyung prepared using other types of Gomyeong. In conclusion, we determine that the best conditions for preparing Toranbyung were boiling for 10 min and using soy powder as the Gomyeong.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.1
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• pp.45-57
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• 2015

Soil moisture is critical for understanding the spatial-temporal variability of hydrologic processes. The distributions of soil moisture have been explored along transect line in hillslope hydrology. In this study, we measured several soil moistures along transect lines during ten-month period at a hillslope located the Cheong-mi catchment. The soil moisture properties were expressed by simple statistical methods (average, standard deviation, and recession slope) and analyzed in terms of soil depths and transects from the seasonal context. Supplementary studies were also performed about the effect of location, topography and soil texture to the soil moisture responses. The spatial distributions of average soil moisture at deep soil layer were distinguished from those at near surface due to the possibility of expected factors such as subsurface lateral flow from upslope, preferential flow and existence of bedrock. The soil moistures in combined line affected from significant contribution of upper transect line were relatively higher(wetter), low variability compared to those in other transect lines and seemed to be under stabilization process. There are confirmed heterogeneity of soil moisture variation related with preferential flow and significant influence of soil texture for soil moisture properties in upslope.

• Journal of Wetlands Research
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• v.16 no.3
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• pp.423-429
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• 2014

Due to high imperviousness rates of the roads, various pollutants originated from vehicle activities and air depositions are accumulated on the road surfaces. The washed-off pollutants can deteriorate the water quality and destroy the aqua-ecosystems with their toxicity. Usually the roads are paved with asphalt and concrete, which can affect on the pollutant concentrations with different frictional forces. Therefore, this research is performed to evaluate the influences of different pavement type on discharged concentrations of pollutant. The results shows the first flush phenomenon was occurred on both pavement types. However, peak concentrations are higher in concrete pavement areas than asphalt pavement because concrete pavement has high contact area with vehicles. The EMCs(Event Mean Concentration) also shows high values in concrete paved roads. As a result of this research, it can be concluded the pavement type is also one of the important affecting factors on pollutant emissions from the roads.

• The Journal of Engineering Geology
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• v.23 no.2
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• pp.105-115
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• 2013

Increasing the river cross-section by barrage construction causes rises in the average river water levels and discharge rates in the rainy season. The time series patterns for groundwater levels measured at 23 riverside monitoring wells along the lower Nakdong River are compared for two cases: before and after water-filling at the Changnyeong-Haman Barrage. Monthly average groundwater levels indicate a distinct increase in groundwater levels in the upstream riverside close to the barrage. River-water level management by barrage gate control in August, during the rainy season, resulted in a 0.1 m decrease in groundwater levels, while water-filling at the barrage in December caused a 1.3 m increase in groundwater levels. The results of hierarchical cluster analysis indicate that seven groundwater monitoring wells and river water levels were in the same group before barrage construction, but that this number increased to 14 after barrage construction. Principal component analysis revealed that the explanation power of two principal components corresponding to river fluctuation, PC1 and PC2, was approximately 82% before barrage construction but decreased to 45% after construction. This finding indicates that the effect of the river level component that contributes to change in groundwater level, decreases after barrage construction; consequently, other factors, including groundwater pumping, become more important. Continuous surveying and monitoring is essential for understanding change in the hydrological environment. Water policy that takes groundwater-surface water interaction into consideration should be established for riverside areas.