• Fire Science and Engineering
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• v.34 no.2
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• pp.49-53
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• 2020

This study aimed to identify the characteristics of 40 chemical accidents that occurred in Jeollabuk-do from 2004 to 2019. During this time, there were 2.5 accidents per year on average in the province; their types were classified as spill/leak, fire, explosion, adverse reaction, and complex. There were 34 leaks and six explosions, and they are categorized as follows: 12 by worker error, 16 from facility defects, and 12 by transport vehicle accidents. The substances involved in these accidents were ammonia (15%), sulfuric acid (12.5%), and silicon tetrachloride (7.5%). Notably, the rate of chemical accidents (75%) is the highest during spring and summer. In order to reduce chemical accidents, first, there should be compliance with the relevant laws. Second, the quality of safety education and training of workers should be improved. Finally, valuable government support is also necessary to improve facilities.

• Plant Journal
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• v.15 no.4
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• pp.30-35
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• 2019

To meet both increasing social demand for reduction of fine dust and the strengthened air pollutant emission standards, this paper indicated performance enhancement of FGD with structural constraints in 500 MW coal fired thermal power plant's. Through modifying internal facilities for flue gases to make swirl in the absorption tower, it made turbulence and increased the efficiency of material transfer, the reaction area and time with the limestone slurry. Therefore, it could reduce dust and enhance the performance of collecting the SO₂. As a result, desulfurization efficiency was improved from 91.61% to 98.43% and dust removal efficiency was improved from 77.4% to 87.08%. Emission density is 7.85 ppm of SO₂ and 4.67 mg/㎥ of dust. This is a level that satisfies emission limit of 25 ppm of SO₂ and 5 mg/㎥ of dust which are the air pollutant emission standards of 2023. The performance enhancement method of this study is expected to be effectively applied to other coal-fired power plants with similar constraints.

• Journal of Environmental Health Sciences
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• v.46 no.5
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• pp.599-609
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• 2020

Objectives: Coronavirus disease 2019 (COVID-19) first emerged in December 2019 in Wuhan, China, and has rapidly become a global pandemic with over 26.4 million confirmed cases and approximately 871,000 fatalities worldwide as of this writing. In the Republic of Korea, disease clusters frequently occurred in long-term care hospitals where the majority of residents are elderly with underlying medical conditions. Despite the fact that public health authorities and local community health centers have put tremendous efforts into preventing the spread of disease, positive cases have continued to occur. Thus, the Korea Centers for Disease Control & Prevention rapid response team decided to conduct an environmental investigation of a long-term care hospital to identify whether environmental contamination has remained and contributed to the spread of COVID-19. Methods: An environmental investigation was conducted at Hospital A. The characteristics of the facility and its HVAC system were assessed by checking the layout and interviewing the people in charge. A total of 64 surface samples were collected from areas of concern, including patient rooms, toilets, elevators, and nurses' station. These samples were tested by a regional health and environmental research institute using real-time reverse transcription polymerase chain reaction. Results: All samples from Hospital A were confirmed to be negative. Through interviews with high-level personnel at the regional community health center, we found that extensive disinfection is frequently performed on potentially contaminated areas in Hospital A in accordance with government guidelines. Conclusion: The environmental control measures implemented in Hospital A had been sufficient for mitigating the risk of further infection, suggesting that such measures may also be effective for other long-term health care facilities.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.2
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• pp.75-86
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• 2007

This process which has a connection of biofilter and sulfur-limestone has been developed to treat organic substances including BOD, COD and SS etc. and to treat sulfur-limestone is for denitrification.. The whole process consists of chemical reaction tank, sedimentation tank, trickling filter, denitrification tank The trickling filter is equipped with a reactor filled with absorptive filter, and the sulfur denitrification tank is filled with sulfur-limestone mixed media. After setting up practical facilities whose capacity is 60 tons a day, we have observed the removal efficiencies of pollutants through 60 experiments during Summer and Winter seasons. The average concentration of polluted water was BOD for 3.6 mg/L, $COD_{Mn}$ for 11.3 mg/L, SS for 2.8 mg/L, T-N for 8.6 mg/L, and T-P for 0.8 mg/L, and the rate of treatment efficiencies 96.5%, 84.7%, 96.5%, 79.2%, and 80.8%, respectively was found through the experiments. The average treatment efficiency for BOD and $COD_{Mn}$ was 85.0% and 55.7%, respectively and the average removal efficiency for NH4+-N was 84.9% in the trickling filter. The removal efficiency in the denitrification tank is as follows; The removal rate of $NO_3^--N$ was as high as 93.2% within the compass of pH 6.3 to 7.3 through $16.8{\sim}37.0mg/L$ flown into $NO_3^--N$ and $0.1{\sim}8.3mg/L$ outflown. It had observed that this process has implemented highly efficient and advanced treatment without external carbon sources and internal recycle during its process. In conclusion, this process is suitable for a sewerage in a small village due to the merits of low power consumption and easy maintenance.

• Quality Improvement in Health Care
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• v.2 no.1
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• pp.86-109
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• 1995

Clinical trials of drugs on humans is the final and most important stage in evaluating the safety and efficacy of the drugs. Good Clinical Practice(GCP) standards were announced in 1987 to protect testees' rights as well as to ensure validity of the clinical trial results, but its implementation has been delayed until now. The purpose of this study is to evaluate the preparedness of the designated institutions to abide by GCP standards during clinical trials, and thereby to determine GCP implementability at the institutions. Survey on the status of clinical trials was conducted for the designated 83 clinical trial hospitals. Response rate was 95.2%. Donabedian's quality assessment model was applied as the basic framework for the study. And the relative - weights for the evaluation items were determined by expert's evaluation. Among the designated 83 hospitals, 39 conducted clinical trials to obtain drug manufacturing approval from 1990 to 1994. Only 19 institutions are found to be able to meet the requirements of KGCP. Structure variables - manpower, organization, and facility -, which are the basic elements for GCP, are evaluated as unsatisfied in many hospitals. Institutions which established IRB accounted for 41 or 51.9%, but those who have a protocol evaluation guideline, or Adverse Drug Reaction(ADR) reporting system were only 12 and 21 institutions, respectively. Also, the institutions providing educational programs on conducting clinical trials are few - 20. The study results indicates that the level of conducting KGCP is unsatisfactory. However, more institutions are expected to be able to meet the standards soon because GCP standards does not require so much regulation on facilities, but stress importance on research methodology and human right. At present as the institutions for clinical trials are primarily training hospitals with residency programs, such efforts as education will accelerate the implementability of GCP in Korea. Institutions must build the appropriate infrastructure and government must prepare to strongly enforce KGCP before it can successfully take place.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2779-2785
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• 2009

Among the livestock, chickens are raised because of the merit ingested protein in low-priced cost of production and are primary livestock increased the consumption of meat. The factors of influencing condition, odor is the most important factor. Odor substances are ammonia, amines, hydrogen sulfide and mercaptan which come from night soil. Livestock are prevented from rearing by means of these odor substances. Though the henhouse is heated using hot air type heater in the winter season, it is ventilated for the control of odor because of the increase of odor concentration. In the present work, composite catalytic system combined the existing facilities(hot air type heater) with catalytic system was developed, it could controled odor and hazardous gas using the oxidation/reduction reaction without extra operating cost. Moreover, the purpose of this work is to develop the catalysts which are cost competitive and can maximize energy efficiency. The catalysts are noble metal(Pt-Rh) and composite transition metal(Mn) type.

• Journal of Navigation and Port Research
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• v.29 no.6 s.102
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• pp.561-566
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• 2005

This study was carried out to amlyze and compare the stability of a 50ton container crane according to various wind load design codes. The wind load was evaluated according to 'The Specification of Port Facilities and Equipments / Specification for the design of crane structures (KS A 1627)' and 'Load Criteria of Building Structures' effected by the ministry of construction & transportation And the uplift forces qf a container crane under this wind load were estimated by amlyzing reaction forces at each supporting point and compared each other. From this study, we noticed that the design wind velocity criteria need to be defined specifically when the wind load is evaluated to design a container crane. And we verified the necessity of the estimation of the uplift forces at each supporting point to analyze a structural stability of a container crane and the maximum compressive force in order to consider the stability of the ground foundation of the berth.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2288-2292
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• 2007

The catalytic activities of nickel-based catalysts were estimated for oxidizing acetaldehyde of VOCs exhausted from industrial facilities. The catalysts were prepared by sol-gel methods of SiO2 and SiO2-TiO2 as a xerogel followed by impregnating Al2O3 powder with the nickel nitrate precursor. The crystalline structure and catalytic properties for the catalysts were investigated by use of BET surface area, X-ray diffraction (XRD), Xray photoelectron spectroscopy (XPS) and temperature programmed reduction (TPR) techniques. These results show that nickel oxide is transformed to NiAl2O4 spinel structure at the calcination temperature of 400 °C in response to the steps with after- and co-impregnation of Al2O3 powder in sol-gel process. The NiAl2O4 could suppress the oxidation reaction of acetaldehyde by catalysts. The NiO is better dispersed on SiO2-TiO2/Al2O3 support than SiO2/Al2O3 and SiO2-TiO2-Al2O3 supports. From the testing results of catalytic activities for oxidation of acetaldehyde, Catalysts showed a big difference in conversion efficiencies with the way of the preparation of catalysts and the loading weight of nickel. The catalyst of 8 wt.% Ni/TiO2-SiO2/Al2O3 showed the best conversion efficiency on acetaldehyde oxidation with 100% conversion efficiency at 350 °C.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.433-438
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• 2005

This study was carried out to analyze the effect of the variation of a wind speed on the stability of a container crane. The wind load according to 'The Requirement of Port Facilities and Equipments / Specification for the design of crane structures (KS A 1627)' and 'Load Criteria of Structures' enacted by the ministry of construction & transportation was evaluated. And the uplift forces of a container crane under this wind load were calculated by analyzing reaction forces at each supporting point and compared with each other. The analytic model was a container crane with uplift capacity of 50ton which was widely used in port.

• Journal of the Korean Institute of Gas
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• v.15 no.4
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• pp.27-32
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• 2011

Management of gas safety is becoming important with increasing use of gas facilities. U-safety system is being promoted as part of national management of gas, and thus real-time and in-situ gas sensor should be developed. Detection method for When the gas sensor is installed in gas conduit, explosion may be likely, because hydrocarbon gases is usually used the difference of thermal resistance between reference and working electrode. Therefore, it is required to detect the hydrocarbons, such as $CH_4$ and CO, at room temperature via electrochemically catalytic reaction. In this study, Pt nanoparticle was doped on the porous gold powder by electrolytic plating method, and then it was used as catalytic electrode for CO oxidation. For Pt/PAu electrode, approximately 21% of CO conversion was obtained. It is noted that Pt/PAu electrode could be used to react the oxidation of hydrocarbon gases at room temperature via applying of external voltage.