• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.9
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• pp.1055-1063
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• 1999

This paper present a conceptual possibilistic approach using fuzzy set theory to manage the uncertainties in the given reliability input date of the practical power system. In this paper, an algorithm is introduced to calculate the possibilstic reliability indices according to the degree of uncertainty in the given data. The probability distribution function can be transformed into an appropriate possibilstic representation using the probability-Possibility Consistency principle(PPCP) algorithm. In this the algorithm, the transformation is performation by making a compromise between the transformation consistency and the human updating experience. Fuzzy classifcation theory is applied to reduced the number of load data. The fuzzy classification method determines the closeness of load data points by assigning them to various clusters and then determening the distance between the clusters. The IEEE-RTS with 32-generating units is used to demonstrate the capability of the proposed algorithm.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.9
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• pp.783-792
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• 2009

This study investigated 31 selected EDCs(Endocrine Disrupting Compounds) and PPCPs(Pharmaceutical and Personal Care Products) in the influent and effluent of a wastewater treatment plant(WWTP) nearby Seoul metropolitan area. The chemical compounds of EDC/PPCPs detected from the plant influent sample include stimulant, X-ray contrast media and fire retardant. The total amount of each compound class were 59.67%, 20.20% and 9.00% respectively. However, in the effluent sample, the major micropolutants detected were oral beta-blocker(30.54%), fire retardant(20.49%), X-ray contrast media(18.17%). The EDC/PPCPs occurrence levels of this study were somewhat lower than previous domestic studies'. When compared to those of overseas, the values were even lower. Some pharmaceutical compound levels particularly measured in European studies were even several thousand times high. This study then compared PECs(Predicted Environmental Concentration) and MECs(Measured Environmental Concentration) of 9 selected pharmaceuticals compounds. The calculated PECs were substantially different with the MECs, while the occurrence order between the PECs and MECs in terms of concentrations of the compounds were similar.

• Journal of Environmental Health Sciences
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• v.42 no.1
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• pp.53-60
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• 2016

Objectives: Preservatives are commonly used in pharmaceuticals, cosmetics and other products to extend the expiration date and prevent the growth of microorganisms. Preservatives are generally effective in controlling mold and inhibiting yeast growth, and against a wide range of bacterial attacks as well. They also adversely affect the quality of sperm and cause precocious puberty in children. This study was performed to analyze seven preservatives used in pharmaceuticals and personal care products. Methods: Five kinds of pharmaceuticals and personal care products (PPCPs) were examined for analysis with a high performance liquid chromatography-diode array detector. Each sample was homogenized and the targeted compounds were extracted with methanol. The suspended particulate was removed by syringe filter. Next, the sample was injected into an HPLC system. The separation of the seven preservatives was achieved with a C18 column and gradient mode. The accuracies were between 73% and 120% and precision was lower than 11.58% (RSD). Results: All of the calibration curves showed good linearity with a coefficient of determination ($r^2$) over 0.999. Among the PPCP samples, the detection rate of preservatives was 32.5% for pharmaceuticals, 44.8% for toothpaste, 76.9% for mouthwash, 40.0% for body lotion and 56.0% for wet tissues. The average concentrations of the preservatives in PPCPs were BA 1141.0 mg/kg, MP 709.8 mg/kg, EP 624.9 mg/kg, PP 216.9 mg/kg, BP 167.8 mg/kg, and TCS 538.2 mg/kg. The most frequently detected preservatives in pharmaceuticals and personal care products were BA, MP and PP. The concentrations of preservatives exceeded Korean regulatory standards in 11 samples of medicines, three of mouthwash and two of body lotion. Conclusion: We found that most of the PPCP samples contained various preservatives. It is necessary to identify which preservatives were used and to determine the level of preservatives in PPCPs and to assess the health risk to susceptible populations such as children.

• Journal of Korean Society on Water Environment
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• v.35 no.6
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• pp.574-579
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• 2019

As interest in health issues increases, it is imperative to ensure good water quality from wastewater treatment plant effluent to preserve environmental health. In particular, currently there is a lack of water ecosystem risk assessment on pharmaceutical substances remaining in effluent. In this study, antidepressant escitalopram (ESC), antiepileptic carbamazepine (CBZ) and lead, which impact the behavior of aquatic organisms, were used to test their impact on the potential behavior of zebrafish. Zebrafish have been widely used in toxicological assessment studies due to the ease of handlinggenerically and genetically. It was possible to observe changes in the growth of organisms through monitoring the embryos' cognitive and behavior assessment. In this study, the embryo lethal dose test showed that the lethal concentration of ESC and CBZ was at 10 ppb, which is below the water quality criterion (100 ppb), increased by 32.5 % and 40 %, respectively. In the cognitive test, it was found that the cognitive ability function decreased by 22 % and 17% for ESC(500 ppb) and CBZ(1,000 ppb) respectively relative to control. Based on these results, it is necessary to initiate efforts to remove these trace pollutants from sewage treatment facilities to protect the health of aquatic organisms.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.2
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• pp.211-216
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• 2000

In this paper, experimental investigations were carried out to remove NOx, SOx simultaneously from a simulated combustion flue gas [$NO(0.02%)-SO_2(0.08%)-CO_2-Air-N_2$] by using a pulse corona induced plasma chemical processing. Discharge domain of wire-cylindrical plasma reactor was separated from a gas flow duct to avoid unstable discharge by aerosol particle deposited on discharge electrode and grounded electrode. The NOx, SOx removal was experimentally investigated by a reaction induced to ammonium nitrate, ammonium sulfate using a low price of aqueous NaOH solution and a small quantity of ammonia. Volume percentage of aqueous NaOH solution used was 20% and $N_2$ flow rate was $2.5{\ell}/min$ for bubbling aqueous NaOH solution. Ammonia gas(l4.82%) balanced by argon was diluted by air and was introduced to a main simulated flue gas duct through $NH_3$ injection system which was in downstream of reactor. The $NH_3$ molecular ratio(MR) was determined based on [$NH_3$] and [$NO+SO_2$]. MR is 1.5. The NOx removal rates increased in the order of DC, AC and pulse, but SOx removal rates was not significantly effected by source of electricity. The NOx removal rate slightly decreased with increasing initial concentration. but SOx removal rate was not significantly affected by initial concentration. The NOx, SOx removal rates decreased with increasing gas flow rate.