• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.5
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• pp.140-147
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• 2012

This study developed a flowerbed type infiltration system that could control the amount of runoff discharge under a certain level estimated its proper design infiltration rate, and analyzed the effects of its implementation. Analyzing the performance of infiltration system is the one of the essential processes that should be under review to predict its effects after implementation when a rainwater infiltration system is included in a district-based plan. To estimate the unit design infiltration rate of this system, the runoff decrease effect was analyzed by varying the unit infiltration rate of the system applied to the parking lot adjacent to the Korea Institute of Construction Technology laboratory building by using a water balance analysis program. After varying the unit design infiltration to $0.1{\sim}3m^3/m^2.day$ to analyze the variation in the rate of runoff, 80% of the runoff was infiltrated at $1.0m^3/m^2.day$, and the unit infiltration design rate at the time was 0.0416(m3/m2.hr). It was also found that the unit design infiltration rate obtained from a field infiltration test of the developed system was about $0.045m^3/hr$. Based on this study, it was possible that infiltration rate is estimated to consider the economic scale and environmental effect. It is significant to apply the spatial plan of rainwater infiltration system as green infrastructure.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.12
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• pp.2125-2134
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• 2000

This research was to develope the economical treatment processes of the landfill leachate to meet the legal discharge standards. To achieve this purpose, experiments were conducted in laboratory to choose the optimum process and to obtain the design factors before a pi!ot-scale test. The concept of the process developing in this research was using the reverse osmosis system. The submerged membrane bio-reactor was used to achieve pre-treatment of reverse osmosis system and the concentrate was treated by evaporator with land fill gas as a fuel. The results of the research showed that SS, $BOD_5$, $COD_{cr}$, $NH_4{^+}-N$ and T-N were removed 99.0%, 43.0%, 12.9%, 48.5% and 18.7% respectively in the submerged membrane bio-reactor. The reverse osmosis system could remove $BOD_5$, $COD_{cr}$, $NH_4{^+}-N$ and T-N as an efficiency of97.5%, 97.6%, 79.7% and 85.4% respectively. The evaporator could remove $COD_{cr}$, $NH_4{^+}-N$ and T-N as an efficiency of 90.5%, 50.6% and 63.3% respectively. However the condensed water of the evaporator was not satisfied the legal standard and should be treated in reverse osmosis with the pre-treated leachate.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.1
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• pp.79-86
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• 2010

Effects of operating parameters such as applied voltage, solution conductivity, ferrous ion concentration, electrode material on phenol degradation by pulsed corona discharges were investigated in laboratory scale experiments. The increase of applied voltage enhanced the phenol degradation by generating more energetic electrons. The solution conductivity inversely affected phenol removal rate in the tested ranges because the increase of conductivity decreased the electric field strength through the liquid phase. The addition of ferrous sulfate promoted the phenol degradation through the OH radical production by the Fentonlike reactions between ferrous ion and hydrogen peroxide generated by pulsed corona discharges. Catechol and hydroquinone were detected as primary intermediates of phenol degradation and the decrease of pH and the increase of conductivity were observed probably due to the generation of organic acids. Almost all of the initial phenol was disappeared and 29% of total organic corbon (TOC) was removed in the condition of 0.5 mM of ferrous sulfate after approximately 230 kJ of discharge energy transferred to the reactor.

• Journal of the Korean Society for Railway
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• v.16 no.1
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• pp.40-46
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• 2013

Based on Korean railway design standards, the thicknesses of the reinforced roadbeds of conventional and high speed railways are different, and so too, for the size distribution of the ballast particles. Accordingly, considerable cost would be required to increase operating speeds of conventional lines, in particular related to changing from a ballasted track system to a ballastless one. In this study, applicability of a roadbed which supports conventional ballasted track, for use as a ballastless track for a high speed rail line was examined. A reinforced roadbed for a conventional railway is 20cm thick, and the type of material used for a conventional reinforced roadbed is M-40 (crushed gravel for road embankments). A dynamics test was conducted to evaluate the occurrence of the permanent settlement of the track substructure. These results suggest that, without changes to the track substructure, an operational speed of 400km/h is feasible with a ballastless track. This result; however, is from laboratory experiments. Further studies, such as numerical analyses or field validation, are required.

• Korean Journal of Veterinary Research
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• v.35 no.4
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• pp.699-712
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• 1995

The present study, to evaluate the effect of vitamin E on the oxidative stress in STZ-treated rat and BB rat, was investigated the biochemical enzyme activity in the serum, and malondialdehyde and carbonyl group in the RBC membrane, liver and microsomal fraction after vitamin E and/ or insulin treatment. Results obtained through the experiments were summarized as follows; 1. Effect of vitamin E and/or insulin treatment in STZ-treated rat 1) Lipid peroxidation level in RBC membrane, liver and microsomal fraction was significantly decreased in vi. tamin E and/or insulin treatment group, and especially more significantly decreased in vitamin E with insulin treated group. 2) Protein oxidation level in RBC membrane, liver and microsomal fraction was significantly decreased in vitamin E and/or insulin treatment group. And it was especially more significantly decreased in RBC membrane and liver of vitamin E with insulin treated group. 3) In the enzyme activity in the serum, the activity of AST and ALT was not altered in all experimental group. The increased ALP activity in STZ-treated group was significantly decreased in insulin treated group and vitamin E with insulin treated group. 4) Decreased level of albumin and creatinine after STZ treatment was significantly increased in vitamin E and/or insulin treated group. 5) Level of glucose, cholesterol and triacylglycerol in serum: Glucose level was not significantly different in vitamin E treated group compared to STZ control group. But it was significantly different in the insulin treated group and vitamin E with insulin treated group compared to STZ control group. The cholesterol content in the serum was significantly increased in STZ control group compared to normal control group. And except low dose vitamin E treatment group, it was significantly decreased in vitamin E and/or insulin treated group compared to STZ control group. The triacylglycerol content in the serum was significantly decreased in STZ control group and increased in high dose vitamin E treated group and vitamin E with insulin treated group. But it was not significantly different in low dose vitamin E treated group and insulin treated group compared to STZ control group. 2. Effect of vitamin E and/or insulin treatment in BB rat 1) Lipid peroxidation level in liver was decreased by vitamin E with insulin treatment compared to insulin treatment. But it was not different in microsomal fractions. 2) Protein oxidation level in liver and microsomal fraction was decreased by vitamin E with insulin treatment compared to insulin treatment only in microsomal fractions. These results suggest that the combination treatment of vitamin E and insulin could prevent the oxidative change of lipid and protein of the RBC membrane, liver and microsomal fraction in STZ-treated rats and BB rats.

• Korean Journal of Veterinary Research
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• v.35 no.4
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• pp.713-727
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• 1995

The present study was investigated fatty acid composition of the phospholipid in the RBC membrane, liver and microsomal fraction after vitamin E and/or insulin treatment to evaluate the effect of vitamin E on the oxidative stress in STZ-treated rat and BB rat. Results obtained through the experiments were summarized as follows; 1. Effect of vitamin E and/or insulin treatment in STZ-treated rat 1) In the insulin treated group and the combination treated groups of vitamin E with insulin, body weights were increased compared to STZ-treated rat(STZ control group). Especially it was more significantly increased in the combination treated group of high dose vitamin E with insulin. 2) The composition of fatty acids of the phospholipid in RBC membrane, liver and microsomal fractions was shown a decreased C16:1, C18:1, C20:4 and an increased C16:0, C18:0, C18:2 in STZ control group compared to normal control group. In RBC membrane, liver and microsomal fractions after vitamin E with insulin treatment in STZ-treated rat, effect on the composition of fatty acids of the phospholipid was shown the result of a decreased C16:0, C18:0, C18:2 and an increased C16:1, C18:1, C20:4. 3) Hemolysis rate of the RBC to $H_2O_2$ was increased in the STZ control group and it was decreased below the hemolysis level of normal control group by vitamin E treatment. 2. Effect of vitamin E and/or insulin treatment in BB rat 4) Only in microsomal fraction, fatty acid composition was different between insulin treatment group and vitamin E with insulin treatment group. It was increased C16:0 and C18:1, and decreased C18:0 and C18:2 in vitamin E with insulin treatment group: But C20:4 was not different in two groups. These results suggest that the combination treatment of vitamin E and insulin could prevent the oxidative change of fatty acids in P-lipid of the RBC membrane, liver and microsomal fraction in STZ-treated rats and BB rats.

• Journal of Chest Surgery
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• v.2 no.1
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• pp.115-132
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• 1969

The normal physiological values of Korean mongrel dogs were studied, comparing them with foreign references, on the basis of control physiological data measured on 110 cases out of the dogs submitted to the experiments in our department. The hemodynamic measurements varied widely between the both limits of reported normal control data, with the mean value of heart rate $140.4{\pm}26.6$/min., and both the systolic and diastolic arterial blood pressures $137.2{\pm}31.7$mmHg and $104.7{\pm}14.4$ mmHg, as well as the venous pressure of $9.11{\pm}2.18$ cm.$H_2O$. Hematologically, the number of red blood cells $4,571,000{\pm}767,000$per cu.mm., the amount of hemoglobin $11.57{\pm}3.74$ gm/dl and the hematocrit $37.3{\pm}7.2$ per cent, were equally the values a little lower than the reported normal means. However, the white blood cells were within the reported normal limits both in number, $10,384{\pm}4,877$ per cu. mm and their differential counts with slightly broader ranges of variation. The platelet count was $149,800{\pm}47,000 $per cu. mm and was also far below the normal, while the coagulation time $9.03{\pm}2.69$min. and the prothrombin time $13.17{\pm}6.52$sec were within normal limits, though a little prolonged. The serum electrolytes, Na $146.6{\pm}10.44$mEq/L.,K $4.46{\pm}0.84$mEq/L., CI $118.3{\pm}7.88$mEq/L. and Ca $11.45{\pm}5.62$mg./dl, and the blood glucose level of $94.9{\pm}31.79$mg./dl were essentially not different from the reported normal values. The serum proteins, total protein $7.15{\pm}1.41$gm/dl., albumin $4.09{\pm}0.77$gm./dl. and globulin $3.18{\pm}0.88$gm/dl. were included near the higher limits of the reported normal levels. The thymol turbidity 0.1-3.04 units were normal in 10 cases, and the cephaline flocculation was within normal range except 2 cases out of 26 dogs, showing two positive in 24 hours. And the nitrogen series, NPN $34.61{\pm}10.29$mg/dl. and BUN $12.77{\pm}6.37$mg./dl. were normal. It may be concluded that from the point of view of hereby measured physiological data compared with the foreign references, the Korean mongrel dogs have a compatible laboratory data with only the special regards to their tendency toward anemia in red blood cell series.

• Journal of Korea Water Resources Association
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• v.43 no.7
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• pp.657-666
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• 2010

The adjustment processes of mining pits in the disturbed channels by sand or gravel mining were investigated by laboratory experiments in this study. The pit migrated with speed when the river bed was steep. The pit migrated slow and steady when the pit was filling with sand, but the pit migrated with speed after the filling processes was finished. The submerged angle of repose in the pit was nearly constant during the pit was filling. The pit was filled with sand with speed as the channel slope was increased. It took time for the pit to be filled with sand as the pit dimension was increased. This meant that the disturbed channels by sand or gravel mining to adjust the new environment was dependent on the slope of the channels and the dimension of the pits. The dimensionless pit length was short and the dimensionless pit depth was shallow as the time was increased. The dimensionless pit depth was shallow, but the dimensionless pit migration speed was increased as the dimensionless shear velocity and the migration speed of the pit were increased. The dimensionless pit depth was increased with the dimensionless bar migration speed. The shape of the pit was deformed and migrated downstream in accordance with the location and shape of the biased bar front which was developed upstream.

• Korean Journal of Plant Resources
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• v.24 no.5
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• pp.613-621
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• 2011

Plastic house and laboratory experiments were conducted to determine the effects of substrate components and shade degrees on plant growth and physiologically-active substance content and antioxidant activity of Panax ginseng. No significant difference in growth characteristics among substrates was observed. However, shade treatment also significantly reduced leaf area, chlorophyll content, root length, and shoot and root fresh weight (P<0.05) with increasing of the degree. Total phenolics level [mg ferulic acid equivalents (FAE) $kg^{-1}$ DW] was higher in root parts (25.8 to 28.4 mg $kg^{-1}$) than shoot parts (20.7 to 23.8 mg $kg^{-1}$) of Panax ginseng, and with shade (23.7 to 28.4 mg $kg^{-1}$) than without shade (20.7 to 25.8 mg $kg^{-1}$). However, total flavonoids [mg naringin equivalents $kg^{-1}$ DW] was more detected in the shoot part (17.4 to 26.8 mg $kg^{-1}$) than in the root part (6.7 to 7.0 mg $kg^{-1}$) of Panax ginseng. Methanol extracts from the Panax ginseng plants dose-dependently increased DPPH free radical scavenging activity as a antioxidant potential, and the activity was higher in shoot parts (31.1 to 36.5%) than in root parts (24.9 to 28.7%), and without shade than with shade. In conclusion, shade affects plant growth as well as physiological activity of Panax ginseng under plastic house condition.

• Journal of Korea Water Resources Association
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• v.51 no.8
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• pp.729-737
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• 2018

This study investigates the sediment processes the Improved-pneumatic-movable weir through laboratory experiments considering changing channel slopes. Experimental results show that the delta migrates towards the weir and the delta height increases as time passes. Moreover, as the delta approaches the weir, the delta migration speed decreases. As the dimensionless delta location increases, the effective height of dimensionless delta and the dimensionless reservoir capacity increases. Therefore, under the same slope conditions, the sediment deposition volume of the delta is small as the channel slope is mild. This means that the channel slope affects the development of the delta in the upstream of the Improved-pneumatic-movable weir. At the beginning of the experiment, the foreset slope is mild. However, the foreset slope of the delta increases with water depth as the delta migrates downstream. Moreover, as the slope is mild, the ratio of delta front length to delta height is close to 1, and the dimensionless delta height and the dimensionless delta migration speed decrease. As the delta height increases, the water depth, the velocity approaching to the weir and the delta migration speed decrease.