• 한국환경과학회지
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• 제22권4호
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• pp.471-479
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• 2013

The present study was conducted to judge the applicability of field quality control by children's goods manufacturers by assessing the contents of heavy metals such as Pb and Cd in outdoor play goods for children through measurement using Portable XRF and comparing the results through detailed analyses using ICP. Heavy metal contents of 711 part samples of 505 products were measured using XRF. According to the results, the ratio of products that exceeded the Pb and Cd content standards specified under the Quality Management and Safety Control of Industrial Products Act were 2.4% and 2.6%. Many products certified for self-regulated safety exceeded the standards and thus it was considered that harmful chemical material centered safety management systems would be necessary. Detailed ICP analyses of some products were compared and the results showed deviations of 0.9~80.8% from XRF results. The reasons for this are deviations in the characteristics of measured cross sections and the homogeneity of samples resulting from sample preparation methods, etc. Therefore, it is considered that field quality control will be applicable if measuring methods are efficiently established based on product characteristics and calibration curve preparation methods are established through quality control.

• 한국환경보건학회지
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• 제46권5호
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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.

• 한국대기환경학회지
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• 제25권5호
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• pp.410-419
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• 2009

Generally, air pollutant emission at workplace is estimated by two methods: indirect methods using emission factors and direct methods based on CEMS (Continuous Emission Monitoring System). CAPSS (Clean Air Policy Support System) is a representative indirect method and the national air pollutant database of Korea. However, characteristics of some workplaces may create a gap between CAPSS and CEMS data. For improving of emission data accuracy, emission data of CEMS (named CleanSYS) equipped at 138 target workplaces were compared with those of CAPSS. As a result, $SO_x$ and $PM_{10}$ emission levels obtained by CAPSS were lower than those of CleanSYS. $SO_x$ and $PM_{10}$emission ratios were 61.5% and 71.2% lower respectively, showing the biggest gaps. On the other hand, $NO_x$ emission of CAPSS was higher by 10.4%. $SO_x$ showed the biggest difference in 'Energy industry combustion' and $NO_x$ did in 'Production Process' within the SCC category. $PM_{10}$ presented a large gap in 'Manufacturing industry combustion.' The differences in $SO_x$ between the two systems occurred because some large-size facilities lack pollution controllers or efficient pollution controllers. Based on this study, CAPSS emission database of Korea will improve accuracy through adopting CEMS emission system, which enables more efficient national atmospheric policies and workplace management.

• 한국환경농학회지
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• 제37권3호
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• pp.179-188
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• 2018

BACKGROUND: Reclamation of heavy metal-contaminated agricultural fields has intensively been done to ensure the soil quality and food security. This study evaluated the efficiency and longevity of current physical and chemical approaches for heavy metal-contaminated soils. METHODS AND RESULTS: Concentrations of 0.1 N HCl-leachable trace metals of Cd, Pb, and As from the stabilizing agents-treated soils decreased by 50%, 70%, and 40%, respectively, compared to the control. Among the stabilizing agents, the $CaCO_3$ was the best for stabilization. For physical stabilization, the soil dressing reduced the concentrations of Cd, Pb, and As by 88%, 94%,and 88%, respectively, compared to the control. Moreover, the dilution of the contaminated soils decreased the metals by an average of 25.3% when compared with the control. The longevity of each stabilization method was determined by using the availability assessment of heavy metals in the soils. Results showed that the leaching methods using HCl and $NH_4NO_3$ had 120 and 32 weeks longevity, respectively. Interestingly, any stabilization efficacy was not found over the time for Cd and Pb (i.e., cation metals), whereas the stabilization efficacy of As was sharply decreased under 50% after 32 weeks. However, the change of metal concentration was not significant with the physical stabilization compared to the chemical stabilization. CONCLUSION: The stabilization methods should carefully be selected based on long-term monitoring under climate conditions.

• Molecules and Cells
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• 제41권6호
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• pp.495-505
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• 2018

Several bacterial etiological agents of streptococcal disease have been associated with fish mortality and serious global economic loss. Bacterial identification based on biochemical, molecular, and phenotypic methods has been routinely used, along with assessment of morphological analyses. Among these, the molecular method of 16S rRNA sequencing is reliable, but presently, advanced genomics are preferred over other traditional identification methodologies. This review highlights the geographical variation in strains, their relatedness, as well as the complexity of diagnosis, pathogenesis, and various control methods of streptococcal infections. Several limitations, from diagnosis to control, have been reported, which make prevention and containment of streptococcal disease difficult. In this review, we discuss the challenges in diagnosis, pathogenesis, and control methods and suggest appropriate molecular (comparative genomics), cellular, and environmental solutions from among the best available possibilities.

• 한국환경복원기술학회지
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• 제23권6호
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• pp.43-55
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• 2020

The study was performed in order to derive the management methods of revegetation space on embankment upper in the shoulder of expressway. The pilot study was conducted in 2013 on the test road section of the Jungbu Inland Expressway (Smart Highway) and continues to be monitored until 2020. In the test, three commonly used methods for weed control were applied. In the early two to three years, most of the methods were effective in controlling weeds. However, at the end of six years, weed suppression effects were different for each treatment. Vegetation coverage was 90% in the untreated control, 70-80% wood chip mulching method, 50-60% solidification method, and 20% sheet mulching method. The sheet method was found to be the most effective given the low vegetation coverage was effective in controlling weeds. The wood chip mulching method is promoting weed growth over time, and weeds are invading as the effect of soil hardening is reduced in the place where the soil hardener is treated. Among the methods applied in the test, mulching the sheet is the most effective, but it is important to use a durable sheet. In the future, it is necessary to find ways to control weeds on road shoulders, considering both economic and environmental aspects. For the proper management in the shoulder of expressway set target zone is needed. Clear standards for weed control on expressway should be established. And the technology to be applied must be durable for 3 years or more and must be able to suppress the amount of weeds to a level of 20% or less.

• Tuberculosis and Respiratory Diseases
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• 제79권4호
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• pp.234-240
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• 2016

Transmission of tuberculosis (TB) is a recognized risk to patients and healthcare workers in healthcare settings. The literature review suggests that implementation of combination control measures reduces the risk of TB transmission. Guidelines suggest a three-level hierarchy of controls including administrative, environmental, and respiratory protection. Among environmental controls, installation of ventilation systems is a priority because ventilation reduces the number of infectious particles in the air. Natural ventilation is cost-effective but depends on climatic conditions. Supplemented intervention such as air-cleaning methods including high efficiency particulate air filtration and ultraviolet germicidal irradiation should be considered in areas where adequate ventilation is difficult to achieve. Personal protective equipment including particulate respirators provides additional benefit when administrative and environmental controls cannot assure protection.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.25-32
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• 2005

In China, environmental noise policies are composed of correlated laws adopted by the Standing Committee of the National People's Congress and promulgated by the President of the country, regulations promulgated by the State Council and/or local government, standards issued by the Standardization Administration Committee (SAC) under the State Council. The laws mainly include the 'Environmental Protection Law' and the 'Law on Prevention and Control of Pollution From Environmental Noise' Regulations are often applied to a special noise pollution phenomenon of wide influence. They are generally only effective in a given area and/or a specific period. Tens of correlated standards specify the noise level limits of different functional zones of land use and of different equipment, machines, devices, appliances etc., and the measurement methods. In this presentation, a brief introduction to these policies and their operations is given and discussed. The conclusion is that the policies supply an effective legislative basis for environmental noise prevention and control in China, but still a lot of work should be conducted and completed to strive for a quiet society.

• Journal of Biosystems Engineering
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• 제43권4호
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• pp.342-351
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• 2018

Purpose: Recently, an increasing number of farms have been cultivating shiitake mushrooms using a sawdust substrate and a cooler/heater. In this study, an attempt was made to develop an environmental control system using a heat pump for cultivating high-quality shiitake mushrooms. Methods: An environmental control system, consisting of an air-to-water type heat pump, a thermal storage tank, and a radiator in a variable opening chamber, was designed and fabricated. The system was also installed in the cultivation facility of a farm cultivating shiitake mushrooms so as to compare the proposed control system with a conventional environmental control system using a cooler-condensing unit and an electric hot water boiler. Results: The uniformity of the environment was analyzed through environment measurements taken at several positions inside the cultivation facility. It was determined that the developed environmental control system is able to control the variations in temperature and relative humidity to within 1% and 3%, respectively. In addition, a maximum temperature difference of $30^{\circ}C$ (maximum of $35^{\circ}C$, minimum of $5^{\circ}C$) and a maximum relative humidity difference of 30% (maximum of 90%, minimum of 60%) can be attained within 30 min inside the cultivation facility through the cooling of the heat pump and heating of the radiator in a variable opening chamber. Thus, the developed control system can be used to cultivate high-quality shiitake mushrooms more effectively than a conventional cooler and heater. Conclusions: In comparison with a conventional environmental control system, the developed system decreased the yield of ordinary mushrooms by 65%, and increased that of high-quality mushrooms by 217%. This corresponds to a 16% increase in gross farm income. Consequently, the developed system is expected to improve the income of shiitake mushroom cultivating farms.

• 한국대기환경학회지
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• 제33권6호
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• pp.533-543
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• 2017

As the public interest in environmental issues increased, the "Act On The Integrated Control Of Pollutant-Discharging Facility" was enacted. Through the integrated environmental pollution prevention act in which 19 industries with large environmental impacts are sequentially applied, pollutants can be managed in a medium-integrated manner and integrated permission of the business unit is possible and BAT can be applied to enable a scientific and proactive environmental management system. In order to facilitate the implementation of integrated environmental pollution prevention act with these advantages, the BAT BREF should be published, modified and revised every 5 years considering the level of scientific development. This study reviewed the issues to be considered in applying BAT and the types of BAT and focused on presenting improvements and development direction when revising and supplementing the standards in the future based on these contents. For this purpose, when revising the standards, it will be necessary to reflect on the domestic situation, to expand the TWG(Technical Working Group) of small-scale workplace experts, and to exchange opinions with business places that have similar processes for each waste type through a systematic total inspection. In addition to these methods, by establishing a resident participation system through information disclosure, it is expected to be used as a guideline for environmental management of business places not subject to integrated permission of less than 3 types as well as those subject to integrated permission.