• Journal of Korean Society on Water Environment
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• v.24 no.3
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• pp.291-296
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• 2008

Pollutant unit load developed by Ministry of Environment (MOE) in 1995 has been a tool commonly used for water quality management and environmental policy decision. In spite of the convenience of the method in application, the shortcoming of the method has been criticized especially for nonpoint source pollution from paddy field. In this paper the estimation procedures of pollutant unit load from paddy field in the major river basins (Han, Nakdong, Geum, and Youngsan river) were investigated, and some suggestions of improvement measures of the unit-load estimation were made. The investigation showed that the distributions of rainfall, run-off, and run-off ratio, which are the most important factors affecting discharge amount of pollutants, were not similar among river basins. Such differences seemed to result in a greater unit loads estimation at Han river and at Nakdong river watersheds compared to the others. Therefore, it is not likely to be rationale to compare unit load among the watersheds without consideration of such differences. We conclude that estimation of unit-load through an intensive monitoring of pollutant discharge is crucial for better estimation of unit-load. When such an intensive monitoring is not easy due to labor and expense restriction, we suggest that unit-load should be estimated based on the storm-events which is a representative rainfall-runoff event of the area.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.7
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• pp.726-731
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• 2005

Sedimentation is treated as the most important unit process in waterworks, and plays great role on turbidity removal efficiency. Rectangle sedimentation basin is the most widely accepted sedimentation process. But it has some problems with short-circuit flow and density flow caused by temperature and influent turbidity variation. To solve these problems, installation of rectification wall was suggested, but not generally fully accepted in field. Because hole of rectification wall cause jet flow. In this research, use of moving baffle was investigated. Moving baffle was designed to induce uniform velocity at every section of water flow. The baffle walls was made from soft fiber materials. The baffle walls with flow of sedimentation basin moves at same speed. It is like that it controls density flow and short-circuit flow and induce uniform velocity at every section of water flow in sedimentation basin. When moving baffle was operated retention time of sedimentation basin was extended to 1 hours. When it talked again and the effluent time of highest concentration of the chlorine ion from 100 minutes was extended to 160 minutes. Turbidity removal efficiency was tested with different operation modes(continuous and batch) with influent turbidity and retention time. It was revealed that turbidity removal efficiency carl be improved up to 36%(continuous mode) and 58%(batch mode) respectively. Consequently if moving baffle introduces in Rectangle sedimentation basin, it forecasts that the turbidity improvement above 30% will be possible.

• Journal of Korea Water Resources Association
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• v.35 no.5
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• pp.511-523
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• 2002

In order to develop the weir with high reaeration efficiency, the reaeration experiments at linear weir, ogee spillway type weir, and labyrinth weirs were conducted and the results were compared. The effect of roughened crest was also analyzed. It was found from the experiments that the oxygen transfer efficiency at the ogee spillway type weir was the lowest and that at the linear weir was second lowest among the weirs used in the experiments. It was also revealed that the reaeration efficiencies of the labyrinth weirs increase as the included angles become smaller. The roughened crest which causes the disintegration of overflow was found to increase the reaeration efficiency significantly. On the basis of the results of the experiments, the pilot construction of the labyrinth welt with included angle of 30 degree was made. The labyrinth weir was made up by assembling the frame and then filling the ripraps into the frame. The ripraps were exposed at the crest to split the overflow. The average value of oxygen transfer efficiency observed at the pilot weir was 0.18. It is expected that the results from the experimental study and the field data of the pilot weir would serve for the improvement of water quality by the weirs with high reaeration efficiency.

• Journal of Wetlands Research
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• v.21 no.3
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• pp.224-235
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• 2019

Rapid urbanization poses three major problems in urban streams. The first problem is the reduction of soil wetting from rainfall as the impervious area increases. Decrease in soil wetting causes serious distortion in the water cycle of urban streams. The second problem is the increase of non-point sources pollutants by urban land use, and the third problem is the combined sewer overflows in the old city center. Increased non-point sources pollutants and combined sewer overflows are associated with water cycle distortion, which increases water pollution in urban streams. In this study, EPA SWMM was constructed for the Busan Oncheon-stream watershed in order to suggest solutions for these three problems, and the bio-retention cells installation project was planned by benchmarking the actual projects in New York City. Water cycle improvement and reduction of non-point sources pollutants and combined sewer overflows for each project scenario were analyzed together with required budgets.

• Journal of Wetlands Research
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• v.21 no.4
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• pp.374-383
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• 2019

The Wangpo stream located in the Buyeo-gun was a small stream with both low water quality and quantity due to the cultivated land and settlement area through the stream. In order to restore ecosystem, the Sustainable Structured wetland Biotop system was applied to treat 1,500 to 7,000 ㎥/d amount of effluent water pumped from the Buyeo sewage treatment plant facility as well as inflowed from nonpoint pollution source of Wangpo stream. As a result of continuous monitoring for 2 years from 2016 to 2018 after completing restorative construction, the average BOD₅ as an index of organic pollution was 7.3 mg/L and the average effluent concentration became 2.1 mg/L, showing an improvement by 71.2%. The average inflow concentration of T-N was 7.953 mg/L and the average outflow concentration was 3.379 mg/L, showing 57.5% of improvement. The average inflow concentration of T-P was 0.177 mg/L and the average outflow concentration was 0.052 mg/L, showing about 70.7% improvement. The results of ecological monitoring after creating biotope by reuse of treated waste water and nonpoint pollution source of the Wangpo Stream are as follows. The plant taxa founded in water SSB(Sustainable Structured wetland Biotop) system of the Wangpo Stream was total 41 species in 21 families, showing a higher proportion of naturally introduced plant than that of artificially planted species. In case of other terrestrial animals, both amphibian and reptile group were confirmed as 3 species in 6 families, avian group was 25 species of 15 families, and mammal group observed 5 species in 5 families, respectively. All species have been created and enhanced through purified water inhabited in the SSB(Sustainable Structured wetland Biotop) system as a treatment wetland, eventually migrating to the Wangpo Stream.

• Journal of the Korean Society of Food Culture
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• v.5 no.4
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• pp.463-472
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• 1990

This research was carried out as a basic survey to provide more effective and improved food service for the soliders of the Armed Forces who are serving to defend the Republic of Korea subjects were selected randomly who were serving in the army for a short-term. Following is the result of a survey regarding the situation of their meals, dietary life, and their food preference of 190 kinds of foodstuffs. As a result of surveying the dietary life of the soldiers, they indicated that there was dissatisfaction in the current Food Service because it lacked tasted and the same kind of meals were being served too frequently with regard to this, many subjects expressed that they were eating out because of the quality of they get from the regular meal service the meals, that is they were eating in restaurants to resolve their dissatisfaction over the quality of the meals. It was also surveyed that in the current meals there is a need to diversify ways in preparing food, increase the number of dishes, and improve the tasts of the food by using improved cooking method. It seemed that the soldiers were satisfied in the quantitative level of the current food service but that there is a need to improve the meals in quality. Following is the result of a survey on the preference of foodstuffs. In case of rice as the stationary food, mixture of five-grain plain white cooked rice showed a higher propensity compared to plain whte boiled rice. This shows that soliders prefer various cereals in their rice. Soliders liked soup made from meat better than vegetable soup or soup made from fish. Especially there was a high performance for beef soup. Soliders liked One-dish meals such as fried rice or boiled rice with asserted mixtures, noodled, and dumplings on the whole-soliders generally liked vegetables and they liked uncooked vegetables better than cooked vegetables. Generally everyone liked beverages and there was a high preference for dessert. Among various rice cakes soliders liked songpyon(rice cake steamed on a layer of pine needles) and injolmi (cake made from glutinous rice). On the other hand, soliders did not like food prepared with fish, biscuits and candy very much. In the way of preparing food, soliders liked food that were fried in deep far rather than food cooked in water. Also they liked pot stem better than soup. As examined in the survey, those surveyed wanted improvement in the quality and diversity of the food rather than increase the number of food and quality. Therefore there is a need for diversified supply and demand of quality of meal service.

• Journal of Animal Science and Technology
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• v.53 no.4
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• pp.289-296
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• 2011

Swine industry in Korea plays an important role in providing the meat for domestic consumption, and the number of pigs in Korea was about 9.72 million heads as of June, 2010. Meat quality is used to describe any traits which impact the consumer acceptability of fresh meat products. Meat color, firmness, water holding capacity, ultimate muscle $pH_{24h}$ (measured 24 hours post-mortem), shear force, and intramuscular fat percentage (IMF) are generally accepted as important indicators of meat quality and ultimately, consumer acceptance of fresh pork. The objective of this study was to estimate genetic parameters for meat quality traits in Berkshire pigs. The heritability estimates for muscle $pH_{24h}$, lightness (CIE $L^*$), NPPC marbling were 0.61, 0.56 and 0.57, respectively, The heritability estimates for drip loss, cooking loss, shear force were 0.51, 0.66 and 0.56, respectively. The phenotypic correlations between $pH_{24h}$ and lightness (CIE $L^*$), drip loss, cooking loss were negative, ranging from -.45 ~ -.13. The genetic correlations between muscle $pH_{24h}$ and lightness (CIE $L^*$), drip loss were negative, ranging from -.35 ~ -.32. Genetic parameters obtained herein indicate that genetic improvement of muscle $pH_{24h}$ is not related to the NPPC marbling of meat, but rather to improved lightness(CIE $L^*$) and drip loss. Genetic trends of meat quality traits showed increased muscle $pH_{24h}$ and decreased cooking loss and drip loss.

• Analytical Science and Technology
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• v.12 no.4
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• pp.312-317
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• 1999

Quality control was carried out the three analytes, BOD, COD, TN, TP of high and low concentration for thirteen laboratories. Evaluation values of Quality control was determined from average value which were made by six times test, repeatedly and periodically. This value had not only error ratio of within 5% from prepared sample value but also high precision of standard deviation, 0.44 (BOD, low concentration), 2.15 (BOD, high concentration), 0.12 (COD, low concentration), 1.63 (COD, high concentration), 0.35 (TN, low concentration), 1.99 (TN, high concentration), 0.05 (TP, low concentration), 0.14 (TP, high concentration). Upper (Lower) Warning Limit (ULWL) and Upper (Lower) Acceptance Limit (ULAL) values made from quality control chart. Three (5.30, 9.70, 5.30 mg/L) and five laboratories were over ULAL value in low and high BOD concentration, respectively. Two (41.00, 30.60 mg/L) and four laboratories were over ULAL value in low and high COD concentration, respectively. while, other eleven laboratories appeared reliable data. One laboratory (0.70 mg/L) was over ULAL at low TN concentration, while other eleven laboratories had reliable values. In case of high TN concentration, eleven laboratories were over ULAL value, it should be focuced for improvement of reliability about measurement and analysis of TN. Four (1.14, 0.45, 0.64, 1.49mg/L) and seven laboratories were over ULAL in low and high TP concentration, respectively.

• Korean Journal of Environmental Agriculture
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• v.18 no.2
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• pp.126-134
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• 1999

To provide the basic information for the water improvement and control of water resource in Nakdong river districts, the physico-chemical characteristics of water in four main streams and three branch streams of the river were investigated through 36 times totally, one time per each month from January in 1995 to November in 1997. The pH values of each sites in main or branch stream of Nakdong river was pH $6.3{\sim}9.3$ range, pH range of Jukpo and Namji area at spring and fall was almost over pH 8.5, which was exceeded the water quality standard for agriculture. DO values of Nakdong river was almost $8.0{\sim}13mg/l$, except for Kangchang area in downstream of Kumho river. BOD values in Dasa area where was prior to mixing of Kumho river was $1.5{\sim}4.8mg/l$, which was under the water quality standard for agriculture(8mg/l), but BOD values followed mixing of Kumho river was over the permit standard of agricultural water as $3.8{\sim}8.9mg/l$ in Koryung, $3.4{\sim}8.4mg/l$ in Jukpo and $3.3{\sim}7.8mg/l$ in Namji according to time or season. Especially, BOD values at Gangchang area in Kumho river were $7.6{\sim}18.5mg/l$, which was over the water quality standard for agriculture and so Kumho river was a main pollutant: source of Nakdong river. COD values of main stream of Nakdong river was over the permit standard of agriculture(8mg/l) as $5.2{\sim}13.5mg/l$ in Koryvng, $5.0{\sim}12.7mg/l$ in Jukpo and $5.0{\sim}12.2mg/l$ in Namji according to time or season. And COD values was much high rather than BOD values and its gap of concentration was increased along with downstream. $NH_4-N$ of main stream of Nakdong river followed mixing of Kumho river($0.5{\sim}13.1mg/l$) was the highest affected in Koryung($0.18{\sim}5.0mg/l$) and detected much more in winter than in summer. T-N in Koryung($4.96{\sim}12.06mg/l$) followed mixing of Kumho river was significantly high rather than $2.86{\sim}4.86mg/l$ in Dasa, $4.20{\sim}8.20mg/l$ in Jukpo and $3.18{\sim}8.64mg/l$ in Namji, which was almost over the permit standard of agricultural water(1.0mg/l). T-P in Koryung($0.10{\sim}0.58mg/l$) also was significantly high rather than those $0.07{\sim}0.36mg/l$ in Jukpo and $0.08{\sim}0.4mg/l$ in Namji as over the standard of agricultural water(0.1mg/l). The concentration of T-N or T-P in Nakdong districts was trended of increasing in every year.

• Journal of Ginseng Research
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• v.5 no.1
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• pp.8-23
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• 1981

Color is one of the most important quality factors of red ginseng (Hong-sam) which is processed from fresh ginseng (Panax ginseng C. A. Meyer). Therefore, a study of characteristics of browning mixtures of aqueous fresh ginseng extracts, factors which accelerate the browning of the aqueous extracts, and the antioxidant activity of the browning mixtures may contribute to the improvement of the color and other quality of red ginseng and other ginseng products such as ginseng extracts. In the present study, factors which affect the Maillard-type browning reaction of aqueous extracts of fresh ginseng roots were investigated firstly by adding various concentrations (0.001-0.5M) of arginine or glucose solutions, by varying the browning reaction temperatures and durations. Secondly, some characteristics such as brown color intensity, amounts of water-soluble and ether-soluble extracts, amounts of non-dialyzable materials, pH, viscosity, and reactivity with 2,2'- diphenyl -1 - picrylhydrazyl and antioxidant activity of the browning mixtures of the aqueous fresh ginseng extracts with small amounts of 0.1 M arginine, 0.1 M glucose, and distilled water at various browning temperatures and reaction time were studied. The results of the present study are as follows. 1. Color intensity (absorbance at 470 nm) of the browning mixtures was increased by adding various concentrations of arginine solution to the fresh ginseng extract, but the addition of the same amount of glucose solution did not increase the color intensity. 2 The amounts of water- or ether-soluble extracts, amounts of non-dialyzable materials were slightly greater in case of the browning mixtures of the fresh ginseng extract with 0.1M arginine solution than in case of the browning mixtures of the fresh ginseng extract with the same amount of 0.1 M glucose solution. In the process of the browning reaction, the pH of the browning mixtures of the fresh ginseng extract with 0.1 M arginine solution decreased slightly, while that of the browning mixtures with 0. 1 M glucose solution was almost constant. 3. The color intensity (absorbance at 470 nm) of the browning mixtures of the fresh ginseng extract with 0.1 M arginine or 0.1 M glucose solutions did not correlate well with the reducing power or the antioxidant power of the browning mixtures. The antioxidant activity of 90% ethanol extracts from the earlier stages of the browning mixtures of the fresh ginseng extract with the arginine solution was almost comparable to that of the 90% ethanol extracts from the later stages of the corresponding browning mixtures. The browning mixtures of only the fresh ginseng extract or of the fresh ginseng extract with the glucose solution showed considerable antioxidant activity, although both showed less brown color intensity than the fresh ginseng extract with he arginine solution.