• Journal of Wetlands Research
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• v.18 no.3
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• pp.301-312
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• 2016

This study has performed comparative analysis on characteristics of contaminated 35 tributaries on seasonal variation/point discharge load/pollutant distribution of water quality factors(8) in order to understand the effect of the watershed in Nakdong River Basin. As a results, the water quality of $BOD_5$(Biochemical Oxygen Demand), Chl-a(Chlorophyll a) and Fecal E. Coli shows II grade at tributaries of more than 50% without COD(Chemical Oxygen Demand), TP(Total Phosphate), TOC(Total Oxygen Carbon) and TN(Total Nitrogen) factors. The specific discharge(Q) were occupied about 54.4% (19 sites) as $0.05m^3/sec/km^2$ value. Among these results, the contaminant level of Dalseocheon, Hyeonjicheon, Seokkyocheon 1, Uriyeongcheon and Dasancheon was also high, which has to consider a discharged pollutant load(kg/day). The 35 major tributaries of Nakdong River were included in 7 mid-watershed, such as Nakdong Waegwan, Geumho River, Nakdong Goryung, Nakdong Changnyung, Nam River, Nakdong Milyang, Nakdong River Hagueon. Especially, the discharged pollutant load of Nam River and Geumho River also was high according to the amount of discharge such as Kachang dam, Gongsan dam and Nam river dam. Seasonal difference of the water quality factors such as $BOD_5$, TN, SS and Q was observed largely, on the other hand the TP and Chl-a was not. This is guessed due to the precipitation effect of site, biological and physicochemical degradation properties of pollutant and etc. The co-relationship between the seasonal difference and water quality factors was observed using a Pearson correlation coefficients. Besides, the Multiple Regression analysis using a Stepwise Regression method was conducted to understand the effect between seasonal difference and water quality factors/regression equations. As a result, the Multiple Regression analysis was adapted in the spring, summer and autumn without the winter, which was observed high at spring, summer and autumn in the order COD/TP, Chl-a/TOC, TOC/COD/$BOD_5$ water quality factors, respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.1
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• pp.159-165
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• 2018

In recent years, universal design concepts have been introduced that are designed to make everybody more comfortable and safe to use for products, buildings, environments, services, and so on. In the case of urban railroad history, it is important to maintain facilities that incorporate the universal design concept because it is an important facility that serves as a base of city life and there are various users. This research is the last annual task of 5 years as part of the project of "Development of Technique to Improve the Convenience of Urban Railway History User" by the National Institute of Transportation Technology Promotion Agency. The purpose of this study is to develop criteria and method of facilities convenience evaluation based on UD and to evaluate user convenience by selecting test bed station. For this purpose, the UD principle of the historic facilities of Weihai Urban Railway was established and detailed evaluation criteria were presented. As a result of evaluating the test bed history using the 5-point Likert scale of the joint research institute / railway operating agency / expert, 50.3% of convenience improvement was achieved. As a result of evaluating the applicability according to the UD principle, 48.7% Respectively. The evaluation criteria and methodology based on the UD suggested in this study is a quantitative method for evaluating UD application of urban railway facilities in the future.

• Korean Journal of Microbiology
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• v.51 no.2
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• pp.97-107
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• 2015

Wetlands constitute a transitional zone between terrestrial and aquatic ecosystems and have unique characteristics such as frequent inundation, inflow of nutrients from terrestrial ecosystems, presence of plants adapted to grow in water, and soil that is occasionally oxygen deficient due to saturation. These characteristics and the presence of vegetation determine physical and chemical properties that affect decomposition rates of organic matter (OM). Decomposition of OM is associated with activities of various extracellular enzymes (EE) produced by bacteria and fungi. Extracellular enzymes convert macromolecules to simple compounds such as labile organic carbon (C), nitrogen (N), phosphorus (P), and sulfur (S) that can be easily taken up by microbes and plants. Therefore, the enzymatic approach is helpful to understand the decomposition rates of OM and nutrient cycling in wetland soils. This paper reviews the physical and biogeochemical factors that regulate extracellular enzyme activities (EEa) in wetland soils, including those of ${\beta}$-glucosidase, ${\beta}$-N-acetylglucosaminidase, phosphatase, arylsulfatase, and phenol oxidase that decompose organic matter and release C, N, P, and S nutrients for microbial and plant growths. Effects of pH, water table, and particle size of OM on EEa were not significantly different among sites, whereas the influence of temperature on EEa varied depending on microbial acclimation to extreme temperatures. Addition of C, N, or P affected EEa differently depending on the nutrient state, C:N ratio, limiting factors, and types of enzymes of wetland soils. Substrate quality influenced EEa more significantly than did other factors. Also, drainage of wetland and increased temperature due to global climate change can stimulate phenol oxidase activity, and anthropogenic N deposition can enhance the hydrolytic EEa; these effects increase OM decomposition rates and emissions of $CO_2$ and $CH_4$ from wetland systems. The researches on the relationship between microbial structures and EE functions, and environmental factors controlling EEa can be helpful to manipulate wetland ecosystems for treating pollutants and to monitor wetland ecosystem services.

• Economic and Environmental Geology
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• v.44 no.5
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• pp.399-412
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• 2011

A DEM (digital elevation model) is produced using a digital topographic map and is now a commonly used tool in geologic surveys. This study aimed to clarify the relationship between knickpoints and faults in the Namdae stream by analyzing a DEM of the area. The Namdae drainage basin was divided into three subbasins (S1, S2 and S3) and their knickpoints developed for the middle to mid-upper regions were extracted from the DEM. The relative steepness Ks and concavity depending on the incision rate was higher in S1 than in S2 and S3 regions. We assumed that the incision rate caused by active erosion resulted from several faults crossing the basins rather than differences in rock types. There are 77 knickpoints in the Namdae drainage area, including the low-ranking branch, and 24 of thses are on the main river system (S1, S2, S3). Of these 77 knickpoints, 27 (38%) are matched by faults, and from the three basins, 13 (54%) correspond with faults, indicating that the knickpoints are connected closely with the faults. For example the average Ks (relative steepness), was 38.8, but in the overlapping area of the Samdang and Doocheon faults the Ks value was 42.99~43.39. We suggest that the faults resulted in geomorphic deformation such as the high-Ksn knickpoints. There was little evdence of relationship between the knickpoints and rock boundaries, with 54% of the knickpoints distributed on the S1, S2, and S3 subbasins. We concluded that the drainage basin knickpoints are the result of fault movement and are a type of geomorphologic deformation that could be useful for surveying Quaternary faults or fault extension.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.5
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• pp.2178-2188
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• 2012

This study is based upon 200 final responses from a survey conducted for 153 nurses and 147 nursing students in Busan and Gyeongnam province from september to october 2011. It is carried out to compare and understand the spiritual needs of nurses and nursing students that are inclined to be more exposed unhealthy people rather than healthy people. In this study, the level of spiritual care needs was divided into five fields such as 'love and fellowship', 'hope and peace', 'meaning and purpose of life', 'acceptance of death' and 'relationship with God' and was investigated. As a result, the love and fellowship was the highest level in group of nurses (r = 3.82) and the relationship with God was the lowest one (r = 2.73). In contrast, a group of nursing students showed that love and fellowship was the highest level (r = 3.92) and relationship with God was the lowest (r = 2.99) among five fields. There were statistical significances between nurses and nursing students in 'acceptance of death' and 'relationship with God' (p < 0.05). When looking at correlation between fields of spiritual needs of nurses, the correlation between 'meaning and purpose of life' and 'hope and peace' was the highest (r = .699) and the correlation between 'relationship with God' and 'hope and peace' was the lowest (r = .247). As the result of analysis on correlation between fields of spiritual needs of nursing students, the correlation between 'meaning and purpose of life' and 'hope and peace' was the highest (r = .660) and the correlation between 'acceptance of death' and 'relationship with God' was the lowest (r = .277). Therefore, it would be imperative to develop a more efficient and systemized education program for the spiritual care of nursing patients, on the basis of understanding the spiritual needs of nurses and nursing students.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.411-420
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• 2007

This study was conducted to increase sweetpotato utilization and to determine the vegetative value of sweetpotato tips by investigating the phenolic compounds, antioxidative effect in oil, electron donating ability, nitrite scavenging effect and ACE inhibition activities. The phenolic compounds present in sweetpotato tips are the gallic, chlorogenic, gentisic, caffeic, couramic and ferulic acid, which are 16-122 times higher compared to other vegetables such as spinach, soybean sprout, and perilla leaves. In each solvent extract, the total phenolic compounds(175.8 mg/g) was composed of 55% EtOAc extraction and 39% BuOH extract, respectively. The results of induction period using the Rancimat method showed that the antioxidant activity of SP tips was higher than the tocopherol or BHT. The relative levels of each solvent extract in SP tips were as follows: EtOAc>BHT>BuOH>Tocopherol>Water>$CHCl_3$>Hexane. The peroxide value was measured every 5 days for 25 days during storage and results showed that the peroxide value, the tips, tuberous root and tocopherol were lower compared to spinach, soybean sprout and perilla leaves. Nitrite scavenging effects were excellent in sweetpotato tips, perilla leaves and soybean sprout, especially, inhibition rate of perilla leaves(72%) were superior to the others. In process of solvent extraction, activity of BuOH and water extractions were the best. ACE inhibition activity in sweetpotato tips was 1.5 times higher than in tuberous roots and $1.9{\sim}3.7$ times higher than in spinach, soybean sprout, perilla leaves.

• Korean Journal of Environmental Agriculture
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• v.31 no.4
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• pp.344-350
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• 2012

BACKGROUND: To design and develop a constructed wetland for effective livestock wastewater treatment, it is necessary to understand the removal mechanisms of various types of pollutants in constructed wetlands. The objective of this study was to evaluate the treatment efficiency of pollutants under different types of fraction in constructed wetland system for treating piggery wastewater. METHODS AND RESULTS: The piggery wastewater treatment plant that consisted of activated sludge tank, aerobic and anaerobic beds was constructed. The concentration of COD(Chemical oxygen demand) in effluent by fraction was 71.5 mg/L for soluble COD, 142 mg/L insoluble COD. The concentration of SS(Suspended solid) in effluent by existing form was 102 mg/L for volatile SS, 15.5 mg/L for fixed SS. The concentration of T-N(Total nitrogen) and T-P(Total phosphorus) in effluent by existing form were 12.8 mg/L and 3.05 mg/L for dissolved form, 35.0 mg/L and 1.93 mg/L for suspended form. The removal efficiencies of COD, SS, T-N and T-P in hot season(summer and autumn) were higher than those in cold season(spring and winter). The removal efficiencies of COD, SS, T-N and T-P in effluent were 98.0, 99.0, 98.2 and 99.2% for all seasons, respectively. CONCLUSION(S): The results indicated that removal types of pollutants were insoluble COD(ICOD), volatile SS(VSS), dissolved T-N(DTN) and dissolved T-P(DTP) in constructed wetlands for treating piggery wastewater.

• Korean Journal of Environmental Agriculture
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• v.31 no.4
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• pp.351-358
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• 2012

BACKGROUND: Constructed wetlands for wastewater treatment are vegetated by wetland plants. Wetland plants are an important component of wetlands, and the plants have several roles in relation to the livestock wastewater treatment processes. The objectives of this study were to investigate the growth characteristics and nutrient absorption of water plants in constructed wetlands for treating livestock wastewater. METHODS AND RESULTS: In this study, livestock wastewater treatment plant by constructed wetlands consisted of $1^{st}$ water plant filtration bed, $2^{nd}$ activated sludge bed, $3^{rd}$ vertical flow(VF), $4^{th}$ horizontal flow(HF) and $5^{th}$ HF beds. Phragmites communis TRINIUS(PHRCO) was transplanted in $3^{rd}$ VF bed, Iris pseudoacorus L(IRIPS) was transplanted in $4^{th}$ HF bed and PHRCO, IRIPS and Typha orientalis PRESEL(THYOR) were transplanted in $5^{th}$ HF. Growth of water plants in constructed wetlands were the highest in October. The IRIPS growth was higher than other plant as 264 g/plant in October. The absorption of nitrogen and phosphorus by IRIS were 3.38 g/plant and 0.634 g/plant, respectively. The absorption of K, Ca, Mg, Na, Fe, Mn, Cu and Zn by water plants were higher in the order of IRIPS > THYOR > PHRCO. CONCLUSION(S): The absorption of nutrients by water plants were higher on the order of IRIPS > THYOR > PHRCO in constructed wetlands for treating livestock wastewater.

• Korean Journal of Environmental Agriculture
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• v.28 no.2
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• pp.158-164
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• 2009

Biosorption uses adsorbents derived from non-living biomass and removes toxic metals from industrial wastewater. The objective of this research was to evaluate the potential of low cost biosorbents to remove heavy metal ions (Cd, Cu, Pb and Zn) from aqueous solutions using chemically modified rice husk and saw dust (Pseudotsuga menziesi, Quercus, Populus). Batch-type adsorption experiments were carried out using rice husk and saw dust treated with NaOH and/or tartaric acid in artificial wastewater 100 mg metal/L). The experimental results showed that the adsorption specificity of each biosorbent was Pb > Cu > Cd > Zn irrespective of the types of biosorbents. The adsorption capacity of Pb and Cu onto NaOH-treated sawdust was increased 2${\sim}$3 times compared to the untreated one. In addition, the tartaric acid treatment increased the adsorption capacity of rice husk for Zn and Cd approximately 5${\sim}$10 fold compared to the untreated one. Surface conditions and changes in functional groups by chemical modification of each biosorbent were confirmed by SEM and FT-IR. Overall, the results show that chemical modification increases the metal removal capacity of rice bran and sawdust.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.264-270
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• 2012

This study was performed to compared the effectiveness of individual treatments (electrolyzed water: EW, organic acid, and ultrasound) and their combination on reducing foodborne pathogens from perilla leaves. Perilla leaves were innoculated with a cocktail of Salmonella Typhimurium, Staphylococcus aureus, Bacillus cereus. Inoculated perilla leaves were treated with EW combined with different concentration of acetic acid (0.5%, 1.0%, 1.5%, 2.0%) for 1 min at room temperature. Treatment of 3 pathogens on perilla leaves with electrolyzed water combined with ultrasound (25 kHz) and 0.5% acetic acid was also performed for 1 min. While the numbers of S. Typhimurium and B. cereus showed reduced with increasing acetic acid concentration, there is no difference in the number of S. aureus treated with EW containing 0.5% to 1.5% acetic acid. Discoloration was observed the perilla leaves treated with EW combined with more than 1.0% acetic acid. For all three pathogens, the combined treatment of EW and ultrasound resulted in additional 0.42 to 0.72 $log_{10}$ CFU/g. The maxium reductions of S. Typhimurium and B. cereus were 0.95, 1.23 $log_{10}$ CFU/g after treatment with EW combined with 0.5% acetic acid and ultrasound simultaneously. The results suggest that the treatment of EW combined with 0.5% acetic acid and ultrasound increased pathogens reduction compared to individual treatment.