• 센서학회지
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• 제29권3호
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• pp.211-214
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• 2020

Chlorine dioxide is very effective gas for sterilization or disinfection (in manufacturing), and does not produce harmful by-products after use. However, if its concentration exceeds 10 %, it become explosive and cannot be compressed or stored. Therefore, it is necessary to measure its concentration. In this study, the concentration of chlorine dioxide with a high oxidizing strength was measured using a metal oxide sensor. The sensor was a commercially available TGS series from Figaro. The sensitivity of the sensor was inversely proportional to a low concentration of chlorine dioxide gas below 6 ppm and returned to the initial resistance at about 6 ppm. When the gas concentration reached multiples of 10 ppm, resistance of the sensor increased to several megaohms.

• 한국임상수의학회지
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• 제15권1호
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• pp.1-7
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• 1998

The present study was performed to evaluate circadian rhythm of blood nortisol concentration and change of blood cortisol concentration by various stress type in domestic cats. The ELISA kit for cortisol measurement was evaluated on the effective assay range, day to day variation, within-run variation and accuracy. The results were 1-1,000 ng/ ml, 0.7-5.9%, 0.9-4.5% and 98%, respectively. The circadian rhythm of serum cortisol concentration is presented in cats. Change of serum cortisol concentration was also examined with several stressors, stimulation with hamster as a prey, beep electronic sounds, vehicle transportation and unfamiliar environment. Unfamiliar environment showed most remarkable change in serum cortisol level.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 가을 학술논문 발표대회
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• pp.53-54
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• 2022

There is an increasing demand for prediction of asbestos concentration which has an fatal effect on human body. While demolishing asbestos, the dust scatters and makes workers be exposed to danger. Up to this date, however, factors that particularly influences have not considered in predicting asbestos concentration. Most of the studies could not quantify the distribution of asbestos. Also, they did not use nominal data on buildings as important factors. Therefore, this study aims to build an asbestos concentration prediction model by quantifying distribution of asbestos and using nominal data of buildings based on Artificial Neural Network (ANN). This model can give significant contribution of improving the safety of workers and be useful for finding effective ways to demolish asbestos in planning.

• Communications for Statistical Applications and Methods
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• 제30권5호
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• pp.517-530
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• 2023

Recent studies revealed that fine dust in ambient air may cause various health problems such as respiratory diseases and cancer. To prevent the toxic effects of fine dust, it is important to predict the concentration of fine dust in advance and to identify factors that are closely related to fine dust. In this study, we developed a Bayesian network model for predicting PM10 concentration in Seoul, Korea, and visualized the relationship between important factors. The network was trained by using air quality and meteorological data collected in Seoul between 2018 and 2021. The study results showed that current PM10 concentration, season, carbon monoxide (CO) were the top 3 effective factors in 24 hours ahead prediction of PM10 concentration in Seoul, and that there were interactive effects.

• Current Research on Agriculture and Life Sciences
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• 제7권
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• pp.231-235
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• 1989

Choline과 choline esters인 acetylcholine, methacholine, carbachol, bethanechol이 토끼의 적출장관 운동에 미치는 영향과 각 약물의 $pD_2$값을 산출하여 각각 비교를 하였다. Choline은 최대유효농도가 $10^{-2}M$이었으며 $ED_{50}$은 $2.4{\times}10^{-3}M$이었고 $pD_2$값은 2.619이었다. Acetylcholine은 최대유효농도가 $10^{-4}M$이었으며 $10^{-9}M$에서는 거의 효과가 나타나지 않았고 $ED_{50}$은 $0.5{\times}10^{-5}M$이었고 $pD_2$값은 5.154이었다. Methacholine은 최대유효농도가 $10^{-5}M$이었으며 $10^{-9}M$에서는 거의 효과가 나타나지 않았고 $ED_{50}$은 $9{\times}10^{-5}M$이었고 $pD_2$값은 6.045이었다. Carbachol은 최대유효농도가 $10^{-5}M$이었으며 $10^{-11}M$에서는 거의 효과가 나타나지 않았고 $ED_{50}$은 $5.7{\times}10^{-7}M$이었고 $pD_2$값은 6.244이었다. Bethanechol은 최대유효농도가 $10^{-4}M$이었으며 $10^{-8}M$에서는 거의 효과가 나타나지 않았고 $ED_{50}$은 $3.3{\times}10^{-6}M$이었고 $pD_2$값은 5.480이었다. Choline esters는 토끼의 적출장관 운동에 대하여 수축을 일으켰으며 각 약물의 potency의 순서는 carbachol이 가장 강하게 나타났고 methacholine, bethanechol, acetylcholine, choline의 순으로 나타났다.

• 한국농촌생활과학회지
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• 제10권2호
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• pp.71-77
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• 1999

This study examined the effect of the pine needle sap administration on serum lipid composition and liver antioxidant defense system in rats fed with high fat diet. Forty eight male Sprague-Dawley rats were divided into six groups. three control groups were fed with 5% lipid diet and three high fat groups were fed with 30% lipid diet. Each group was administered with the following pine needle sap respectively : C-0.0, 1.ml water, C-0.5, 0.ml pine needle sap and 0.ml water C-1.0, 1.ml pine needle sap : H-0.0, 1.ml water, H-0.5, 0.ml pine needle sap and 0.ml water H-1.0, 1.0ml pinus needle sap. After 4 weeks of experimental periods the level of serum obtained and serum lipid was measured respectively. The results were as follows 1. Significant low level was observed for food intake, weight gain, FER in the experimental group administered with the pine needle sap. 2. No difference of the concentration of serum triglyceride was observed out the experimental group with 5% fat diet, however out of the experimental group with 30% fat diet it was low in (H-1.0) group where 1.0ml of the pine needle sap was administrated. 3. In the experimental group with 5% fat diet the concentration of serum total cholesterol and LDL cholesterol was low, especially the hypocholesteromic effect in serum administered by the pine needle sap was significantly high in group C-1.0 where 1.0ml of pine needle sap was administered. In the high fat group provided with 30% fat when the pine needle sap was administered there was a tendency that concentration of total cholesterol and LDL cholesterol decreased however there was no difference significantly. 4. Serum GOT activity was relatively high in high fat diet group. However, when 1$m\ell$ of pine needle sap was administered the activity was lower than that of the control group in H-1.0 group and the activity level was similar with that of the high fat diet group in c-1.0 group. There was no difference of serum GPT activitives followed by the administered of pine needle sap among the experimental group. 5. Liver TBARS levels were high in general in high fat diet group, however it showed no difference when the pine needle sap with different concentration level was administered. The results of this study indicate that the pine needle sap administration was effective in decreasing the food intake and weight gain of the experimental animals in the high fat diet and also effective in decreasing the levels of serum triglyceride, total cholesterol and LDL cholesterol and GOT activities. However it was not effective to change the level of TBARS and GSH -Px activities of liver. Thus, it was found that the pine needle sap administration was effective for the improvement of serum lipid composition condition of the experimental animals in the high fat diet group but it was not effective in the antioxidant defense system of liver.

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권5호
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• pp.30-39
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• 2017

In this study, the predictive toxicity of barley Hordeum vulgare was estimated using a modified terrestrial biotic ligand model (TBLM) to account for the toxic effects of $CuOH^+$ and $CuCO_3(aq)$ generated at pH 7 or higher, and this was compared to that from the original TBLM. At pH values higher than 7, the difference in $EA_{50}\{Cu^{2+}\}$ (half maximal effective activity of $Cu^{2+}$) between the two models increased with increasing pH. As Mg concentration increased from 8.24 to 148 mg/L in the pH range of 5.5 to 8.5, the difference in $EA_{50}\{Cu^{2+}\}$ increased, and it reached its maximum at pH 8. The difference in $EC_{50}[Cu]_T$ (half maximal effective concentration of Cu) between the two models increased as dissolved organic carbon (DOC) concentration increased when pH was above 7. Thus, for soils with alkaline pH, the toxic effect of $CuOH^+$ and $CuCO_3(aq)$ are greater at higher salt and DOC concentrations. The acceptable Cu concentration in soil porewater can be estimated by the modified TBLM through deterministic method at pH levels higher than 7, while combination of TBLM and species sensitivity distribution through the probabilistic method could be utilized at pH levels lower than 7.

• 한국환경과학회지
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• 제22권4호
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• pp.453-461
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• 2013

This study, changes in raw water quality is to indicate on the efficiency of ozone treatment of each pollutant as compared to derive the appropriate operating measures. The appropriate selection for injection rate of pre-ozone and did not inject pre-ozone assess changes in the water. When good water quality, you not injected of pre-ozone to evaluate the economic efficiency of electricity and put the most cost-effective ozone concentration were evaluated. Evaluation remove organic matter and chlorophyll-a concentration level in experiments with each factor of the water DOC> 2.5 mg/L, THMFP> 70 ${\mu}g/L$, Chl-a> 30 $mg/m^3$or less constant process, if you do not need to put pre-ozone showed little impact. It also does not put you in pre-ozone appropriate produce enough power rate savings was calculated as approximately 90 million won. Ability to remove organic materials and the ability to produce disinfection byproducts, and cost-effective decisions by considering the concentration of injection if pre-ozone 1 mg/L was investigated by the appropriate concentration of ozone injection.

• 한국물환경학회지
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• 제36권4호
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• pp.314-321
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• 2020

This study evaluated the applicability of UV-AOP process using medium-pressure UV lamp and H₂O₂ to remove TOC and emerging micropollutants in the effluent from a sewage treatment plant. The UV lamp with higher output(1.6~8.0 kW) showed slightly higher amount of power in removing TOC of 1 mg/L(0.09 kWh/mg/L~0.11 kWh/mg/L), however it was found that there was no significant difference for each cases. In addition, under the condition that the H₂O₂ concentration is sufficient, as the power consumption of the UV lamp increases, the unit TOC removal concentration per unit H₂O₂ decomposition concentration also increases, resulting in effective removal of TOC. The removal rate of 7 new trace contaminants, such as antibiotics by the UV-AOP tested, was at least 89.4%, and the ability to remove the emerging micro pollutants in the process was very effective. But, it was judged that it could not be excluded that the probablity of transforming to oxidated by-product in the case of a low TOC removal efficiency. Depending on the operating conditions of the UV and H₂O₂ processes, a higher BOD concentration is found in the treated water than in the influent, and it is necessary to review the UV power and proper injection conditions of H₂O₂ to maintain the BOD concentration increase below a certain level.

• Applied Biological Chemistry
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• 제38권6호
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• pp.549-553
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• 1995

갈화(Puerariae flos)추출물이 rat의 혈액, 뇌 및 간의 ethanol농도를 유의차있게 감소시켰다. 혈중 ethanol의 감소 효과는 ethanol을 투여한지 1시간 경과한 때에 대조군과 가장 많은 차이를 보였으며 열수 추출물이 80% ethanol 추출물보다 혈중 ethanol 농도를 더 크게 감소시킴이 관찰되었다. Ethanol 투여 10분 전에 갈화추출물 투여가 1시간 전 혹은 10분 후에 투여한 군에 비해서 ethanol 농도 저하에 더 효과적이었으며, 간과 뇌 조직에서도 ethanol의 농도가 저하되는 현상이 관찰되었다. 그러나 이 때 acetaldehyde는 검출되지 않았다. 혈중 ethanol 농도를 가장 효율적으로 감소시키는 갈화 추출물의 적정량은 55.7 mg/kg body weight이었다. 이번 실험을 위해 새로이 시도된 dichloromethane에 의한 시료 추출과 GC를 이용한 분석법은 간단, 신속 하면서도 좋은 분석결과를 보였다.