• Journal of the Korean Institute of Gas
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• v.15 no.3
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• pp.26-30
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• 2011

Instantaneous water heater being not properly installed and not adequately maintained may produce fatal accidents due to carbon monoxide poisoning and suffocation. Insufficient supply of air into the gas appliance for complete burning of the fuel or blocking the outlet of the combustion gas could be a cause to increase carbon monoxide concentration in the exhaust gas of the gas appliance. In this work, the experiments are done with a collected instantaneous water heater using in domestic and the concentration of oxygen near the gas appliance and carbon monoxide in exhaust gas are observed to investigate the risk of instantaneous water heater. The concentration of oxygen near the gas appliance is reduced until 17.7% for the ratio of the ventilation area and floor area being 3.5%. If the outlet of combustion gas is blocked, the carbon monoxide concentration is steeply increasing more than 4,000ppm. Therefore, periodic checking the outlet of combustion gas is more important than vent area to reduce the risk of carbon monoxide poisoning.

• Journal of the Korean Society of Hazard Mitigation
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• v.4 no.3 s.14
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• pp.51-60
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• 2004

Urban flood damage has been caused by drainage deficiency. One of the methods to solve this problem is to construct detention basin and Pumping station and to pump out the water to the river. However, because of rapid urbanization, the capacity of drainage pipelines is sometimes not sufficient enough during the rainy season. Therefore, even though we have enough pumping stations, the inflow of surface water never reaches to the detention area, causing floods in urban area. This research is to find improvement of urban drainage system, estimating drainage pipeline risk. Also, eight models for a computer program were developed for practical use. The models were verified changing precipitation duration, intensity, design period, time distribution model, and etc. This verification was processed focusing that the model can regulate the water level in the detention basin and minimize the effect downstream. As a result Fuzzy models were found to be efficient to lower the water level in detention basin, and decreased about 8 cm in water level of downstream.

• Journal of Society of Preventive Korean Medicine
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• v.4 no.2
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• pp.170-192
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• 2000

Objectives : This study was carried out to research antioxidant effects of Sagunja-Tang(SA) through in vitro and vivo experiments, and tried to investigate the relation between oxidation of tissues and deficiency of Qi. Methods and results : HPLC analysis of glycyrrhizine - known to be the main compound of Radix Glycyrrhizae - was done to certify the quality of SA. Chemiluminescence was initiated by adding tort-butyl hydroperoxide (t-BHP) to rabbit polymorphonuclear leukocytes (neutrophils), and generated reactive oxygen species (superoxide anion) decreased significantly by SA as dose dependent manner. Cell injury during 60 minutes tissue incubation was initiated by adding t-BHP, a hydrophobic hydroperoxide and $H_2O_2$, an water soluble oxidant to rat renal cortical and liver slices. Percentage cell death and lipid peroxidation were estimated by measuring lactate dehydrogenase (LDH) and malondialdehyde (MDA), a product of lipid peroxidation. t-BHP induced % cell death of renal cortical slices and lipid peroxidation of renal cortical and liver slices were decreased significantly by SA. SA decreased significantly % cell death and lipid peroxidation of renal cortical and liver slices induced by $H_2O_2$, too. Acute renal and liver injury induced by $HgCl_2\;and\;CCl_4$, which initiated from free radical, were applied to mice and metabolic data were obtained. Data showed protective effects of SA on acute renal injury caused by decrease of glomerular filtration. SA protected acute liver injury too. Conclusions Through this study, we found that SA have antioxidant effects and tissue oxidation was similar to deficiency of Qi. And further studies have to be followed to certify the mechanisms.

• Journal of Aquaculture
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• v.11 no.3
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• pp.285-294
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• 1998

When Cochlodinium polykrikoides came into the culture tanks through influent cultivated water during the red tides, hundred thousands of commercial flounders were concomitantly killed and many culturists suffered from a great deal of financial loss in the east coast of Korea. It is charactrized by high sinking rate after sunset and the formatino of clump which results in oxygen deficiency by its respiration at tank bottom under condition. We investigated the efficacy of hydrogen peroxide and chlorine dioxide, known to form radicals, for extermination of red tide organism C. polykrikoides. When C. polykrikoides seawater with a density of 6,000 cells/$m\ell$ was treated with 14, 28 and $42mg/\ell$ of hydrogen peroxide, its survival rate was markedly decreased to 9.8, 0.8 and 0.3% respectively immediately after 6 hours of treatments whereas when it was treated with 1.5, 2.1 and $3.0mg/\ell$ chlorine dioxide, its survival rate showed 87.7, 81.3 and 80.1 and 80.1% respectively at the same treatment time. Hydrogen peroxide was the effective agent since it has scarcely injured the cultured olive flounder when exposed to the tested concentration range of $14~28mg/\ell$ with the extermination of almost3 C. polykrikoides during the experimental period of 5 days and has shown the oxygen increase of approximately $1.23mg/\ell$ 2 hours immediately after the flounder by C. polykrikoides in the land-based culture tank is assumed to be not by the toxicity of itself but by oxygen dificiency from the rapid respiration of dinoflagellate clump sunken to the tank bottom.

• CELLMED
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• v.10 no.3
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• pp.19.1-19.6
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• 2020

The kidneys are exposed to toxicants and waste product and can be affected easily by these toxicants and by products of the metabolism. The consumption of adequate water is necessary to remove waste and to keep kidney healthy. Deficiency of liquid in the blood leads to various adverse effects on the kidney. The most common adverse deficiency of liquid in blood is deposition of solid matter in the kidney and subsequently formation of kidney stone. Nephrolithiasis (kidney stone) can be treated by drugs if it is small in size but if it blocks the route due to its big size then surgery is the only way to remove it. The recurrence rate of the problem is very high and it may reappear within 10 years. In Unani literature Hasāh wa Raml al-Kulya (nephrolithiasis) is described in detail. As per Unani literature stagnation of Ghalīz mādda (filthy and viscous matter) in the kidney is the main cause of the formation of kidney stone. Various single and compound formulations drugs are described for the management of kidney stone which are very effective as well as safe. Management is divided into two parts i.e. symptomatic treatment to relieve pain and to methods adopted to remove stone from the kidney. Musakkin-i-Waja'(analgesic) drugs are used for pain while Mufattit-i-Hasāh (lithotriptic) and Mudirr-i-Bawl (Diuretic) drugs are used to remove stone. Majoon Aqrab, Qurs Kaknaj and Dawa-e-Gurda etc. are compound drugs mentioned in literature for removal of kidney stone. Single drugs like Alu Balu, Tukhm Khayar, and Kharkhask etc. are also used for same purpose.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1023-1026
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• 2011

Nitrogen content in soil is a major factor for the crop growth. Ammonium nitrogen in soils is volatilized when soil pH is high. The growth and development problem of strawberry such as color of leaves turning into purple was found when soils were treated with the compost prepared from suspended solids of high pH from the sea. From in-situ analysis it was found that soil pH was 8.33 and nitrate, phosphorous, and potassium contents were relatively low. Nitric acid was added to adjust pH of irrigating water as 1.7, 1.9, and 2.3, then $KNO_3$ $0.25g\;L^{-1}$ and $KH_2PO_4$ $0.25g\;L^{-1}$ were added. It was resulted that soils with pH 1.7 produced the most developed strawberries. Strawberry was recovered by irrigation containing the same solution. From the results, the growth and development problem of the strawberry resulted from low nitrate absorption rate. It was concluded that the growth and development of strawberries were recovered by the reduced soil pH using nitric acid.

• Journal of Environmental Science International
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• v.20 no.9
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• pp.1069-1078
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• 2011

The environmental changes related to hypoxic water mass were investigated at Gamak bay in summer times, June, July and August 2006. The hypoxic water mass was found, in first, at the northern area of Gamak bay on 27 June. This water mass has been sustained until the end of August and disappear on 13 September. In Gamak bay, the hypoxic water mass was closely related to geography. During the formation of oxygen deficiency, changes in dissolved nutrients was studied and found that on surface layer and lower layer, DIN were 0.80 ${\mu}M$~19.8 ${\mu}M$(6.03 ${\mu}M$) and 1.13 ${\mu}M$～60.83 ${\mu}M$(10.66 ${\mu}M$), and DIP were 0.01 ${\mu}M$～0.92 ${\mu}M$(0.24 ${\mu}M$), and 0.01 ${\mu}M$～3.57 ${\mu}M$(0.49 ${\mu}M$), respectively, far higher distribution on lower layer of the water where hypoxic water mass was occurred. The configuration of phosphorus was analyzed to figure out the possibility of release of phosphorus from sediments. It was found that the Labile-Phosphorus, which is capable of easy move to water layer by following environmental change was found more than 70%. Therefore, in Gamak bay, it was found that the possibility of large amount of release of soluble P into the water, while hypoxic water mass was occurred in deep layer was higher. It is suggested that DIP in the northern sea of Gamak bay mainly sourced from the soluble P from lower layer of the waters where hypoxic water mass was created more than that from basin. However, existence form of phosphorus in sediments during normal times, not during creation of hypoxic water mass, needs further study.

• Analytical Science and Technology
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• v.32 no.6
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• pp.225-232
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• 2019

Traceability establishment in chemical measurements is a like a linkage established through an unbroken chain from the measured results to the international system (SI) of units. The primary process for traceability establishment is the purity assignment of a target material to be measured. In this study, we studied the purity assignment of 17α-hydroxyprogesterone (17-OHP). The presence of 17-OHP is indicative of congenital adrenal hyperplasia (CAH) and it builds up due to the deficiency of 21-hydroxylase and 11β-hydroxylase enzyme in the human blood. The purity assignment of 17-OHP was performed by the mass balance method, in which the impurities are categorized into four classes: total related structural impurities, water, residual organic solvents, and nonvolatiles/inorganics. The total related structural impurities were characterized by HPLC-UV; water content was determined by Karl-Fisher coulometer; and the total residual solvents and nonvolatiles/inorganics were determined by TGA. The purity of 17-OHP from a commercial manufacturer was calculated as 993.30 mg/g, and the expanded uncertainty was 0.58 mg/g. The proposed method was validated by uncertainty evaluation and comparing with the actual value of purity.

• 한국해양학회지
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• v.22 no.4
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• pp.246-256
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• 1987

Quantitative benthic invertebrate samples were taken in the Chinhae Bay System, Korea during September 1983 to relate benthic biomass to bottom water dissolved oxgen concentrations Low concentrations of bottom water dissolved oxygen were found to be associated with low benthic biomass and abundance. Benthic biomass(wet weight) and animal numbers decreased logarithmically with bottom dissolved oxygen concentrations. A hypoxic bottom area($\leq$ 2.0$m\ell$/$\ell$, 40% oxygen saturation) extended over most of the bay, covering an area of about 266km$\^$2/, out of a total of 497km$\^$2/. The most affected areas were limited, as a whole, to inner areas of Masan and Haeng-am Bays, Kohyonsong Bay, and the Chinhae Bay Proper.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.770-774
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• 2006

The determination of feasible design flood is the most important to control flood damage in river management. Model parameters should be calibrated using observed discharge but due to deficiency of observed data the parameters have been adopted by engineer's empirical sense. Storage coefficient in the Clark unit hydrograph method mainly affects magnitude of peak flood. This study is to estimate the storage coefficients based on the observed rainfall-runoff events at the four stage stations in the Hantan river basin. Model calibration is the process of adjusting model parameter values until model results match historical data. An objective function which is the percent difference between the observed and computed peak flows is available for measuring the goodness-of-fit between computed and observed hydrographs. By sensitivity analysis for the storage coefficient, it has been shown that the storage coefficients affect the peak flows. The Clark parameters adopted in the River Rectification Basic Plan have been estimated through an iterative process designed to produce a hydrograph with the peak flow.