• Journal of the Korean Institute of Gas
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• v.4 no.4 s.12
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• pp.50-57
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• 2000

Past accidents have shown that vapor cloud explosions are the predominant cause of the largest losses in the chemical and petrochemical industries due to the generation of significant overpressures. Prediction of such overpressure is of great concern and a knowledge of the likely overpressure is needed for the design of equipment, safety cases and emergency planning. For these reasons, risk assessment for vapor cloud explosion is crucial and this assessment can be carried out using the different models including TNT-Equivalency, TNO Hemispherical, TNO Multi-Energy and CFD models. Accordingly, in this paper, the published VCE prediction models are reviewed to provide a critical comparison of the different models used for the quantification of explosion hazards, in terms of the fundamental assumptions employed, and their predictive accuracy

• Journal of Food Hygiene and Safety
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• v.24 no.2
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• pp.148-153
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• 2009

In this study, we have developed a fluorescence chromatographic assay for the quantification of total cholesterol in serum, which is a well-known risk predictor for cardiovascular diseases. The new assay system consists of a chromatographic strip in a cartridge, enzyme buffer containing cholesterol esterase, cholesterol oxidase, horseradish peroxidase, and color developer AEC, and a laser fluorescence scanner. The correlation coefficient (r) between cholesterol concentration and relative fluorescence units was 0.968 in the new assay, showing a reliable linearity through the tested range of cholesterol. Recovery test and comparability with a Hitachi 747 instrument showed 106.5-94% and r = 0.939 (p<0.001), respectively. The new assay system for cholesterol was developed as a pre-POCT platform conducted in clinics since it is fast (8 min) and uses a small volume of sample ($5\;{\mu}l$), and it may be applied for on-site diagnostics to replace expensive automated biochemical analyzer.

• Tuberculosis and Respiratory Diseases
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• v.83 no.3
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• pp.175-184
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• 2020

Quantitative sputum cytometry facilitates in assessing the nature of bronchitis associated with exacerbations of chronic obstructive pulmonary disease (COPD). This is not assessed in most clinical trials that evaluate the effectiveness of strategies to prevent or to treat exacerbations. While up to a quarter of exacerbations may be associated with raised eosinophil numbers, the vast majority of exacerbations are associated with neutrophilic bronchitis that may indicate airway infections. While eosinophilia may be a predictor of response to corticosteroids (oral and inhaled), the limited efficacy of anti-interleukin 5 therapies would suggest that eosinophils may not directly contribute to those exacerbations. However, they may contribute to airspace enlargement in patients with COPD through various mechanisms involving the interleukin 13 and matrix metalloprotease pathways. The absence of eosinophils may facilitate in limiting the unnecessary use of corticosteroids. The presence of neutrophiia could prompt an investigation for the specific pathogens in the airway. Additionally, sputum measurements may also provide insight into the mechanisms of susceptibility to airway infections. Iron within sputum macrophages, identified by hemosiderin staining (and by more direct quantification) may impair macrophage functions while the low levels of immunoglobulins in sputum may also contribute to airway infections. The assessment of sputum at the time of exacerbations thus would facilitate in customizing treatment and treat current exacerbations and reduce future risk of exacerbations.

• Analytical Science and Technology
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• v.17 no.4
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• pp.347-354
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• 2004

We collected crucians (Carassius auratus) and leopard frogs(Rana pipiens) along the Nakdong River and the basin area at five locations from Koomi to Nakdong-estuary. The muscular tissue were separated and a GC-MSD system was used for quantification of PCBs. The 62 PCB congeners which represent total PCB levels were selected as analytes. We determined concentrations of PCBs and studied distribution characteristics by individual congeners and homologs. In the crucian, 24 congeners were detected and total PCB levels ranged from 0.74 to 5.41 ng/g wet weight. In the leopard frog, however, only 2 congeners were detected from Nakdong estuary only. The PCB level was 0.24 ng/g wet weight, around 22 times lower than the crucians. The PCB 153 showed the highest concentrations in the congeners and penta- and hexa-CBs showed the strong predominance which accounted for 78% of the total PCBs.

• Mass Spectrometry Letters
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• v.10 no.2
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• pp.43-49
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• 2019

The aim of this study was conducted to develop an analytical method to determine the concentration of ceftiofur residue in eel, flatfish, and shrimp. For derivatization and extraction, the sample was hydrolyzed with dithioerythritol to produce desfuroylceftiofur, which was then derivatized by iodoacetamide to obtain desfuroylceftiofur acetamide. For purification, the process of solid phase extraction (Oasis HLB) was used. The target analytes were confirmed and quantified in $C_{18}$ column using liquid chromatography-tandem mass spectrometry with 0.1% formic acid in water (A) and 0.1% formic acid in acetonitrile (B) as the mobile phase. The linearity of the standard calibration curve was confirmed by a correlation coefficient, $r^2>0.99$. The limit of quantification for ceftiofur was 0.002 mg/kg; the accuracy (expressed as the average recoveries) was 80.6-105%; the precision (expressed as the coefficient of variation) was below 6.3% at 0.015, 0.03, and 0.06 mg/kg. The validated method demonstrated high accuracy and acceptable sensitivity to meet the Codex guideline requirements. The developed method was tested using market samples. As a results, ceftiofur was detected in one sample. Therefore, it can be applied to the analysis of ceftiofur residues in fishery products.

• Fashion & Textile Research Journal
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• v.23 no.6
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• pp.844-851
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• 2021

Due to the increase in consumers' interest about well-being, interest in eco-friendly products has been increasing due to the harmful effects of various harmful substances contained in textile products and environmental issues. As a result, natural dyes of less potential risk than synthetic dyes and digital textile printing(DTP) textile products with less environmental pollution are drawing attention. However, due to the lack of evaluation criteria for DTP textile products with natural ink and the nature of many colors are stacked layer by layer for dying, the need for simultaneous analysis is emerging. To evaluate whether the natural dye is derived from natural ingredients, the biocarbon content is analyzed. However, in the case of ink made using natural dyes and DTP textile products using natural ink, it is difficult to analyze the biocarbon content due to the limitation of the presence of a small amount of dye contained therein. In this study, we were shown the possibility of natural derived verification by cross-checking the analytes of natural dyes (Persicaria tinctoria, an indigo dye; Dactylopius coccus, a light red; and Curcum longa L., i.e., turmeric) and natural ink with HPLC-MS/MS. The coefficient of determination was 0.999 or higher, the limit of quantification was 0.647-3.664 ㎍/L and a %RSD of each indicator material was less than 10. Then, the extraction amount of natural dyes for five patterned fabrics was analyzed.

• Structural Engineering and Mechanics
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• v.78 no.3
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• pp.351-368
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• 2021

This paper, by applying a reliability-based framework, develops seismic vulnerability macrozonation maps for Tehran, the capital and one of the most earthquake-vulnerable city of Iran. Seismic performance assessment of 3-, 4- and 5-story steel moment resisting frames (SMRFs), designed according to ASCE/SEI 41-17 and Iranian Code of Practice for Seismic Resistant Design of Buildings (2800 Standard), is investigated in terms of overall maximum inter-story drift ratio (MIDR) and unit repair cost ratio which is hereafter known as "damage ratio". To this end, Tehran city is first meshed into a network of 66 points to numerically locate low- to mid-rise SMRFs. Active faults around Tehran are next modeled explicitly. Two different combination of faults, based on available seismological data, are then developed to explore the impact of choosing a proper seismic scenario. In addition, soil effect is exclusively addressed. After building analytical models, reliability methods in combination with structure-specific probabilistic models are applied to predict demand and damage ratio of structures in a cost-effective paradigm. Due to capability of proposed methodology incorporating both aleatory and epistemic uncertainties explicitly, this framework which is centered on the regional demand and damage ratio estimation via structure-specific characteristics can efficiently pave the way for decision makers to find the most vulnerable area in a regional scale. This technical basis can also be adapted to any other structures which the demand and/or damage ratio prediction models are developed.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.405-405
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• 2023

최근 기후변화로 인한 극심한 홍수와 가뭄, 폭염 등 이상 기온 및 기후에 따른 피해가 급격히 증가하는 추세이다. 특히, 집중호우로 인해 도심지에서 발생한 홍수피해는 재산피해뿐만 아닌 수 많은 인명피해가 발생하고 있다. 국내에서는 수재해로부터 인명과 재산을 보호하기 위해 용수공급과 체계적인 치수 사업이 행한 바 있다. 이러한 치수 사업에서 경제성 분석은 사업 전·후 의 편익추정이 완벽히 검증되기 쉽지 않으며, 기존의 치수 계획은 유역 전반에 걸쳐 다양한 홍수 방어시설의 종합적인 고려 없이 제방 중심으로만 수립되어 홍수 발생 시 하천에 과도한 부담을 줄 뿐만 아니라, 사업의 경제성이 낮게 평가되고 있다. 이렇게 국내에서 행해진 하천설계기준에서 제안되었던 경제성 분석 방법은 여러 가지 문제점들을 내포하고 있으며 지속적인 홍수피해가 발생하였다. 이와 같은 문제점들을 개선하고자 개발된 K-FRM(Forean-Flood-Risk Model)은 능동형 하천정보 운영을 통한 다차원 하천관리체계 구축 및 활용을 위한 정량적 위험도 평가 툴로 위험지역에 노출된 자산의 정보(인벤토리), 평가기준, 손상함수, 계량화 원단위 등 홍수피해를 추정하는데 활용이 가능하며, 손실 또는 피해액으로 표현되는 재해손실은 경제적인 관점에서의 위험이며 금전적인 형태로 표현된다. 본 연구에서는 홍수피해액 정량화 모델인 K-FRM을 활용하여 굴포천 유역과 영강 유역을 대상으로 항목별 피해액 산정 후, 정량적 피해액 산정 방법인 EAD(Expected Annual Damage) 분석을 통해 홍수피해위험지도를 작성하여 표준유역별, 행정구역별 홍수피해액을 산정하는 것을 목적으로 한다.

• Journal of the Society of Disaster Information
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• v.19 no.2
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• pp.372-382
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• 2023

Purpose: Suggests measures to improve the construction company's safety management system according to the enforcement of the Severe Accident Punishment Act. Method: The effectiveness of practice-oriented disaster prevention activities was analyzed through safety and health diagnosis of the level of safety and health management system for the countermeasures against the Severe Accident Punishment Act implemented at the construction site and headquarters. Result: The effect of reducing the accident rate and the advancement of the safety and health management system were analyzed by linking the Severe Accident Punishment Act with the safety and health management system, and a plan to improve the safety and health management system was presented through the analysis of the comprehensive results of safety activities before and after the implementation of the Severe Accident Punishment Act. Conclusion: The effect of practical performance measurement was manifested through the improvement of business owners' awareness, the expansion of investment for disaster prevention, and the quantification of disaster prevention activities according to the enforcement of the Severe Accident Punishment Act.

• Korean Journal of Environmental Agriculture
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• v.42 no.2
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• pp.93-103
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• 2023

Persistence and degradation patterns of acequinocyl and its metabolite, hydroxyl-acequinocyl (acequinocyl-OH) and fenpyroximate in butterburs (Petasites japonicus Max.) were investigated after pesticide application. Butterburs, one of the minor crops in South Korea, was planted in two plots (plot A for double and plot B for single application) in a greenhouse. Butterburs samples were also planted in a separate plot without pesticide treatment, as the control. A commercial pesticide containing acequinocyl and fenpyroximate was applied to the foliage of butterburs at hourly intervals after dilution. Recoveries of acequinocyl and acequinocyl-OH were 78.6-84.7% and 83.7-95.5%, respectively; the relative standard deviation of the two compounds were less than 5%. The method limit of quantification was 0.01 mg/kg. The total (Ʃ) acequinocyl residues in butterburs reduced by 96.0% at 14 days and 75.9% at 7 days, in plot A and B, respectively, after final pesticide applications. The biological half-life (DT₅₀) of Ʃ acequinocyl and fenpyroximate, calculated using the dissipation rate, was 3.0 days and 4.0 days, respectively. These data were used to set up maximum residue and safe standard levels when the pesticides are applied to control pests during butterbur cultivation. Risk assessment results showed that the maximum % acceptable daily intake was 7.74% for Ʃ acequinocyl and 0.16% for Ʃ fenpyroximate. The theoretical maximum daily intake of Ʃ acequinocyl and fenpyroximate was 26.3% and 35.8%, respectively. In conclusion, the concentrations of Ʃ acequinocyl and fenpyroximate in butterburs pose no significant health risks to Koreans.