• Korean Journal of Environmental Agriculture
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• v.22 no.3
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• pp.220-226
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• 2003

The residue patterns of procymidone, chlorpyrifos and cypermethrin in peaches were examined. The pesticides were sprayed at 15 days before harvest and then were determined the residue at 0, 1, 2, 3, 5, 7, 10 and 15 days after pesticide application and calculated their $DT_{50}$. Also, the degradation patterns at $4^{\circ}C$ and $20^{\circ}C$ during storage period were compared. Biological half-lives of procymidone, chlorpyrifos and cypermethrin in peaches during the cultivation period were 3.1, 7.2 and 10.4 days, respectively. The biological half -life of procymidone was shorter than the others. During the storage period, half-lives of procymidone, chlorpyrifos and cypermethrin were 16.0, 14.3 and 13.1 days at $4^{\circ}C$ and 4.6, 10.2 and 12.9 days at $20^{\circ}C$, respectively. The degradation rates of these three pesticides in storage period were slower than them in cultivation period. Removal rates were $22.2{\sim}82.9%$ by tap water, and $12.5{\sim}88.8%$ by detergent solution.

• The Korean Journal of Pesticide Science
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• v.16 no.1
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• pp.43-53
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• 2012

In order to monitor the levels of pesticides in environment-friendly stalk and stem vegetables and leafy vegetables selling at markets in Korea. A total of 637 (395 organic agricultural products, 242 pesticide-free agricultural products) samples of 21 stalk and stem vegetables and leafy vegetables were collected twice from markets in July and August 2010 in Korea. Pesticide residues in samples were analyzed by multiresidue method for 240 pesticides using GC-ECD/NPD and HPLC-DAD/FLD. The suspected-pesticides were confirmed with a GC-MSD. As a result of analysis, six pesticides were detected from eight samples, representing a detection rate of 1.3% and amounts of pesticide residues in samples were as follows: alachlor 0.043, chlorfenapyr 0.022-0.324, diazinon 0.024, dicofol 0.009-0.138, dithiopyr 0.008, metolachlor 0.025 mg/kg. Their residue levels were below the MRLs. Estimated daily intakes (EDIs) of the pesticides detected from stalk and stem vegetables and leafy vegetables were less than 25% of their acceptable daily intakes (ADIs), representing that residue levels of the pesticides detected were evaluated as safe for consumption. However, five samples containing pesticide residues were unsuitable environment-friendly products because of pesticides detected more than their 10% MRLs in organic and pesticide-free agricultural products.

• The Korean Journal of Pesticide Science
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• v.17 no.1
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• pp.6-12
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• 2013

Methoxyfenozide and novaluron were sprayed with single and triple treatments separately on peach during cultivation period. Samples were collected over 14 days, 8 times in total (0, 2, 4, 6, 8, 10, 12, 14 days). Methoxyfenozide and novaluron were extracted with acetone and partitioned with dichloromethane, and analyzed by HPLC/DAD. Method Quantitation Limit (MQL) were both 0.005 mg/kg, average recoveries of methoxyfenozide at two fortification levels of 0.05 and 0.25 mg/kg were determined $92.7{\pm}2.9%$ and $102.8{\pm}3.1%$, and novaluron were $98.2{\pm}4.8%$ and $96.7{\pm}9.0%$, respectively. The biological half-life of methoxyfenozide was about 4.41 days at single treatment, and 4.24 days at triple treatments. The biological half-life of novaluron was about 14.81 days at single treatment, and 14.50 days at triple treatments. Dissipation of pesticides on peach was influenced by growth dilution effect. In case of application of methoxyfenozide and novaluron following guidelines on safe use of pesticides, the final residue level was predicted to be lower than Maximum Residue Limit (MRL).

• Korean Journal of Microbiology
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• v.49 no.4
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• pp.360-368
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• 2013

Recently interactive water fountains are gaining popularity in making public facilities in South Korea. The total number of interactive fountains is rapidly growing at the rate of >50% annually. In this study, we performed quantitative microbial risk assessment to estimate infection risks in children by Legionella spp. while playing in interactive fountains. The exposure dose for a given concentration of Legionella in water was calculated using water-aerosol partition rate of Legionella, exposure duration, inhalation rate, and deposit rate of aerosols in the lungs following inhalation. The dose was converted to infection risk by using the dose-response function developed for L. pneumophila. High weight and/or old children, i.e., 12-year children, running around in fountains were the highest risk group by showing >0.05 infection probability for fountain waters containing ${\geq}10^4$ CFU/L Legionella. The result supported the current guideline by Korea Centers for Disease Control and Prevention, which permits use of water with < $10^3$ CFU/L Legionella cells for all purposes. However, the results still warrant further evaluation of the guideline to accommodate risks for children because the dose-response relationship in the model was developed for healthy adults. Further risk assessment studies need to be conducted by employing dose-response model for children who generally carries weaker immune system than adults.

• The Korean Journal of Pesticide Science
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• v.17 no.3
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• pp.162-167
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• 2013

An analytical method for the simultaneous determination of pencycuron in agricultural products was established by using GC-NPD. The method was validated through the guidelines of linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy and precision. The calibration curve of pencycuron was linear over the concentration range of 0.02-2 mg/kg with correlation coefficient of above 0.9999. The limits of detection and quantification were 0.005 and 0.02 mg/kg. Mean recoveries of pencycuron for each sample were 79.6-107.5% at the level of 0.02 mg/kg and 86.4-112.1% at the level of 0.2 mg/kg and 84.0- 104.9% at the level of 1 mg/kg. Relative standard deviation (RSD) in recoveries were all less than 5%. The intra- and inter-day precision (RSD) were 1.6-3.0% and 5.3-11.5%, respectively. The result of validation indicated that this method was accurate and sensitive assay.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.317-324
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• 2020

In this study, a simplified equation for settlement evaluation suitable for the special conditions of a counter facility is suggested. Recently, counter facilities, especially breakwaters, are constructed on soft ground in distant seas as new-port development projects. A counter facility that resists the external forces by self-weight settles easily when constructed on soft ground. Settlement in a counter facility and breakwater is not an important factor for maintenance than a land facility. On the other hand, the current settlement evaluation criteria are excessive for conducting a safety inspection. A settlement evaluation from a safety inspection followed by "Detailed Guidelines for a safety inspection on a counter facility" is used. A simplified equation was proposed to calculate the maximum settlement by applying the allowable residual settlement or settlement stability evaluation results. The suitability of the simplified equation was assessed compared to the assessed rating from the settlement survey results. The proposed simplified equation showed that the settlement evaluation rating had been upgraded. The proposed simplified equation is expected to be used to evaluate the practical structural stability and functional performance.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.2_spc
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• pp.291-303
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• 2020

The Kori-Unit 1 nuclear power plant, which is scheduled to be decommissioned after permanent shutdown, is expected to generate large amounts of various types of radioactive waste during the decommissioning process. Among these, nuclear reactors and internal structures have high levels of radioactivity and the dismantled structure must have the proper size and weight on the primary side. During decommissioning, it is important to prepare an appropriate and efficient disposal method through analysis of the disposal status and the legal restrictions on wastes generated from the reactors and internal structures. Nuclear reactors and internal structures generate radioactive wastes of various levels, such as medium, very low, and clearance. A radiation evaluation indicates that wastes in the clearance level are generated in the reactor head and upper head insulation. In this study, a clearance waste safety evaluation was conducted using the RESRAD-RECYCLE code, which is a safety evaluation code, based on the activation evaluation results for the clearance level wastes. The clearance scenario for the target radioactive waste was selected and the maximum individual and collective exposure doses at the time of clearance were calculated to determine whether the clearance criteria limit prescribed by the Nuclear Safety Act was satisfied. The evaluation results indicated that the doses were significantly low, and the clearance criteria were satisfied. Based on the safety assessment results, an appropriate metal recycle and disposal method were suggested for clearance, which are the subject of the deregulation of internal structures of nuclear power plant.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.1
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• pp.20-26
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• 1997

This paper examines the influences of mining activities on the concentrations of heavy metals in soils in the vicinity of the Dalsung Cu-W mine, Korea. Geochemical surveys were undertaken in the Dalsung mine area and sampling of surface and subsurface soils was carried out. Samples were prepared using 0.1 N HCI, HNO$_3$-HClO$_4$, and aqua regia, and analyzed for Cd, Cu, Pb and Zn by Atomic Absorption Spectrometry. In addition, soil samples were sequentially extracted to investigate the chemical speciation of heavy metals in soils. Heavy metals are highly contaminated in soils in the vicinity of mining area ranging up to 28 $\mu\textrm{g}$/g Cd, 5000 $\mu\textrm{g}$/g Cu, 2390 $\mu\textrm{g}$/g Pb and 930 $\mu\textrm{g}$/g Zn by the method using HNO$_3$-HClO$_4$. The pollution indices calculated with the permissible levels are up to 49 in surface and subsurface soils, which are considered sufficient to raise environmental problems. However, the heavy metal levels by the method using 0.1 N HCl are not higher than Korean standard for soil contamination. It suggests that analytical methods and soil standard should be re-examined. From the results of the sequential extraction methods for metal speciation, total Cu, Pb and Zn concentrations may be determined by analytical methods using HNO$_3$-HClO$_4$ or aqua regia, and exchangeable phase of those metals by the method using 0.1 N HCl.

• The Korean Journal of Air & Space Law and Policy
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• v.19 no.2
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• pp.163-177
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• 2004

Wenn man das fahrl${\"{a}}$ssige Begehungsdelikt in Bezug auf ein Niveau eines Risiko der objektiv vorhandenen tatbestandlichen Erfolgsm${\"{o}}$glichkeit und auf die n${\"{o}}$tige Sorgfaltspflicht, die die T${\"{a}}$ter nimmt, um das solches Risiko abzuhalten, berucksichtigt, ergibt sich der spezielle Fall selten bei der Person, mit dem hoch-gefahrlichen Berufszweig besch${\"{a}}$ftigt ist, auf den die bestehende Allgemeine-Theorie ${\"{u}}$ber das gafahrl${\"{a}}$ssige Begehungsdelikt gleichm${\"{a}}$ssig unanwendbar ist. Bez${\"{u}}$glich des Piloten des Milit${\"{a}}$rflugzeug ergibt sich oftmals ein bestmmter Fall, die die KontroIIe des Risiko gesch${\"{a}}$ftlich uber sein eigenes pers${\"{o}}$nliches Ermessen geht, und er nimmt die Pflicht, die notwendige milit${\"{a}}$rische Zielsetzung zuerst vor allem zu ber${\"{u}}$cksichtigen, wenn auch technisch, klimatisch und umstandehalber ein normales Niveau von Risiko ${\"{u}}$bersteigt wird und zugleich ein bedenkliches hoches Risiko mit sich gebracht wird. Aus diesem Anla${\beta}$ kann man folgem, da${\beta}$ der Pilot des Milit${\"{a}}$rflugzeug ein besonderer Fall ist, auf den die Kriterien in Bezug auf das Gebiet der Regel ${\"{u}}$ber das fahrl${\"{a}}$ssige Begehungsdelikt gleichm${\"{a}}$ssig unanwendbar sind. Und weil die Vermehrung der Gefahr des Flugzeug sofort an die Vermehrung der Gefahr seines eigenen Leben angeschlossen wird und daher es eine M${\"{o}}$glichkeit gibt, da${\beta}$ der Pilot dem Resultat eines Gefahr zum ersten Opfer f${\"{a}}$llt, ist die Regelung in der Punkt der Generalpr${\"{a}}$vention gegen das fahrl${\"{a}}$ssige Begehungsdelikt sinnlos. Und auch muB die militarpolitische Punkt, die Piloten des Milit${\"{a}}$rflugzeug gem${\"{a}}$${\beta}$ dem notwendigen Ausma${\beta}$ auszubilden und das Ausma${\beta}$ zu behalten, aktuell berucksichtigt werden.

• Journal of Food Hygiene and Safety
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• v.31 no.5
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• pp.319-326
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• 2016

Colistin is a last resort antimicrobial agent against multi-drug resistant Gram-negative bacteria. This study was conducted to develop an analytical method to determine colistin in fish and shrimp. The analytes were confirmed and quantified via liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the positive ion mode using multiple reaction monitoring (MRM). The sample was extracted with acidified 5% methanol (containing 0.5% formic acid). Then, solid phase extraction (SPE) was used for cleanup. Matrix-matched calibration curves were linear over the calibration ranges (0.05-1.2 mg/kg) for all the analytes into blank sample with $r^2$ > 0.99. All the values fulfilled the criteria requested by the Codex guidelines. Average recoveries ranged from 85.9% to 107.9%. The repeatability of measurements, expressed as the coefficient of variation (CV, %), was less than 15%. The limit of detection (LOD) was 0.02 mg/kg, and the limit of quantitation (LOQ) was 0.05 mg/kg. This improved method showed higher accuracy and acceptable sensitivity to meet the CAC guideline requirements and is applicable for the analysis of residual colistin (A+B) in fish and shrimp.