• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.123-124
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• 2021

Recently, the danger of fine dust has emerged worldwide. In general, fine dust refers to particulate matter less than 10㎛ and ultrafine dust less than 2.5㎛, and according to the announcement by HEI (Health Impact Research Institute) in 2015, the concentration of ultrafine dust in Korea is the second highest among OECD member countries. It was investigated. In this study, an experiment was conducted to analyze how the diatomaceous earth substitution rate affects the strength characteristics of the permeable block. As the replacement rate of diatomaceous earth increased, the strength decreased. The reason why the strength decreases with the use of diatomaceous earth is that the strength of the hardened body decreases as the structure of the hardened body becomes less dense as the amount of diatomaceous earth increases, and the reason that the strength decreases as the replacement rate of diatomaceous earth increases is the reason for the absorption performance of diatomaceous earth. Therefore, it is judged that a void was generated inside the hardened body while water was absorbed and then evaporated or discharged in the matrix, and accordingly, the strength decreased.

• Journal of the Korean Society of Safety
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• v.21 no.5 s.77
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• pp.46-52
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• 2006

The purpose of this paper is to investigate the removal efficiency of fine dusts as the configuration condition of machinery and equipments in Clean Room and to analyze the flowing behaviors of fine dusts as the layout of Clean Room. The layout of the Clean Room was classified into side layout type, 2 center line type and center concentration type layout, and the flow rates used in this research were 0.22m/s, 0.44m/s and 0.80m/s. Dust removal efficiency as layout change was decreased 37% for side layout type, 31% for 2 center line type and 20% for center concentration type layout at the flow rate of 0.22m/s, compared with the state without machinery and equipments in Clean Room. The efficiency was decreased 42% for side layout type, 22% for 2 center line type and 8% for center concentration type layout at the flow rate of 0.44m/s, and decreased 20% for side layout type, 18% for 2 center line type and 10% for center concentration type layout at the flow rate of 0.80m/s. According to the result of dust removal behavior, $0.3{\mu}m,\;1{\mu}m\;and\;3{\mu}m$ dust except for $5{\mu}m$ showed the higher change of the behavior in side layout type than in center concentration type layout due to the change of air flow. It was confirmed that removal behavior depends on the layout of machinery and equipments as the dust size decreases.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.10
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• pp.1234-1239
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• 2019

This paper proposes a method for measuring fine dust concentration through digital processing of images captured by only existing CCTVs without additional equipment. This image processing algorithm consists of noise reduction, edge sharpening, ROI setting, edge strength calculation, and correction through HSV conversion. This algorithm is implemented using the C ++ OpenCV library. The algorithm was applied to CCTV images captured over a month. The edge strength values calculated for the ROI region are found to be closely related to the fine dust concentration data. To infer the correlation between the two types fo data, a trend line in the form of a power equation is established using MATLAB. The number of data points deviating from the trend line accounts for around 12.5%. Therefore, the overall accuracy is about 87.5%.

• Journal of Korean Society for Atmospheric Environment
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• v.4 no.2
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• pp.57-66
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• 1988

Sandy dust phenomena was observed from April 19 to 23, 1988 in Seoul and suspended particulate was collected by Andersen air sampler during this period. The samples were analyzed for 16 components $(SO_n^{2-}, NO_3^-, Cl^-, PO_4^{3-}, NH_4^+, F^-, Al, Fe, K, Cu, Mn, Na, Pb, Mg, Ca, Cd)$. The conclusions are as follwes: 1. Total suspended particulate concentation during the period of sandy dust phenomena was 489 $\mug/m^3$ (ordinary times: 140-125 $mug/m^3$) 2. The water - soluble ion component concentration of suspended particulate during the period of sandy dust phenomena was few and the metal concentration of that was more than that of ordinary times. 3. The cumulative frequency distribution of suspended particulates in logarithmic diagram did not show similar to normal log distribution during the period of sandy dust phenomena. 4. $SO_4^{2-}, NO_3^-, Cl^-, and PO_4^{3-}$ was onsided to coarse particle, and $NH_4^+$ and F to fine particle in the size distribution of water - soluble ion components during the period of sandy dust phenomena. 5. Metal concentration was high and Al, Fe, Cu, Mn, Na, Mg, and Ca was onsided to coarse particle, and K, Pb, and Cd to fine particle in the size distribution of metal components. 6. During the period of sandy dust phenomena the quantity of respirable particle (< 1 $\mum$) was about 3 times and that of metal components were about 2 - 11 times than that of ordinary times. 7. The concentrations of $NO_3^-, Cl^-, NH_4^+$ at ordinary times were 1.1 - 4 time than that of the period of sandy dust phenomena.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.405-412
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• 2021

The objective of this study is to investigate the environmental impact of fine dust generated at the construction waste intermediate treatment plants, and to propose engineering data and measures to suppress the generation of fine dust to cope with the expected strengthened environmental regulations of the government. The following study conclusions are drawn. 1) T he maximum concentration of fine dust in the workplace was measured as 160㎍/m³ from the crushing operation followed by the point of waste unloading, where focused suppression plan of the fine dust generation is needed in the future. 2) Fine dust concentrations of 113㎍/m³ in wet road conditions and 50㎍/m³ in dry conditions were measured, indicating that fine dust could be reduced by 50% with watering alone. 3) The effect of distancing from the dust source was studied. PM10 during operation of the workplace was measured as about 25㎍/m³ higher than those of the neighboring areas. Whereas there was no significant difference in case of PM2.5 between workplace and neighboring areas. 4) The measurement results of the heavy metal contents showed that these metals did not affect neighboring areas.

• Journal of the Society of Disaster Information
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• v.18 no.3
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• pp.532-541
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• 2022

Purpose: The purpose of this study is to suggest that the existing power demand prediction method including power demand according to fine dust is included in the existing power consumption by using an air purifier to improve the air quality due to fine dust. Method: The method of the study was compared and analyzed using data on the concentration of fine dust in Seoul for three years, household power consumption, and climate observation, and the effect of fine dust on power consumption in Seoul was identified in April and October. Result: The power consumption of home air purifiers in Seoul due to fine dust differences between April and October was calculated to be 2,141 MWh, accounting for 3.4% of the total difference in the use of home appliances in April and October. Conclusion: The effect of fine dust on household power consumption was verified, and power demand prediction is essential for economic system operation and stable power supply, so power consumption due to fine dust should be considered as well as focusing on power consumption of existing air conditioners and heaters.

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.2
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• pp.68-81
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• 2023

This study aims to establish a scenario based on the spacing and arrangement of the roadside trees to reduce heat waves and fine dust in cities that occurred during the urbanization process and to quantitatively analyze the degree of reduction. The ENVI-met 5.0.2v model, a micro-climate simulation program, was used to analyze the degree of improvement in the thermal environment and fine dust according to the roadside tree scenario. As a result of temperature analysis according to street tree spacing, the narrower the distance between roadside trees, the lower the temperature during the day as the number of planted trees increased, and a similar pattern was shown regardless of the distance between roadside trees in the morning and evening. In the case of fine dust emitted from the road, the concentration of fine dust increased slightly due to the increase in roadside trees, but the concentration of sidewalks where people walk increased slightly or there was no difference because of blocking fine dust on trees. The temperature according to the arrangement of street trees tended to decrease as the number of planted trees increased as the arrangement increased. However, not only the amount of trees but also the crown projected area was judged to have a significant impact on the temperature reduction because the temperature reduction was greater in the scenario of planting the same amount of trees and widening the interval of arrangement. In terms of the arrangement, the fine dust concentration showed a difference from the results according to the interval, suggesting that the fine dust concentration may change depending on the relationship between the main wind direction and the tree planting direction. By quantitatively analyzing the degree of thermal environment and fine dust improvement caused by roadside trees, this study is expected to promote policies and projects to improve the roadside environment efficiently, such as a basic plan for roadside trees and a project for wind corridor forests.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.3
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• pp.71-81
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• 2017

Organic dust generated inside livestock facilities includes toxic organic matters such as bacteria and endotoxin. Dust can cause respiratory disease for worker and livestock, and consequently, degradation of welfare and productivity. Influence of dust on livestock workers has been studied since the 1970s. However, exposure limit for cattle farmer has not been established, unlike exposure limit for pig and poultry farmer. Furthermore, study on air quality inside livestock facility, especially inside dairy farm has been rarely conducted in Korea. In this study, dust concentration of TSP, PM10, inhalable and respirable dust has been monitored in the commercial dairy house according to location and working activities. Bedding material inside the stall was one of the major sources of dust. The amount of dust was related to water content level of the bedding material. Dust concentration was relatively high in leeward location, and the highest concentration was measured during TMR mixing process. The maximum value of inhalable dust concentration was 29.1 times higher than the reference value as fine particles drop to the TMR mixer. Dust generated by TMR mixing was presumed to decrease by adjusting moisture and drop height of feed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.143-144
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• 2020

For modern people who spend 80% of the day indoors, indoor air quality is an important factor in their lives. Radon and fine dust, which are indoor air quality pollutants, cause various diseases and lung diseases, so a method is needed to reduce them. Therefore, this study intends to utilize the air pollutant adsorption properties of the carbonized sludge by using the carbonized sludge generated through drying and carbonization of the sludge. As a result of the experiment, it was shown that the concentration of radon and fine dust gradually decreased as the replacement ratio of carbonized sludge increased. The reason is that the carbonized sludge has the ability to adsorb fine dust and radon, so it is considered that it gradually decreases as the replacement ratio increases. Also, the compressive strength and flexural strength tend to decrease gradually. The reason for this is that the carbonized sludge has a number of internal voids, and as the replacement ratio increases, the internal voids increase and the strength decreases. If the refinement and strength of the carbonized sludge replacement ratio are supplemented, it is believed that it will be able to replace the existing finishing materials.

• Journal of Environmental Health Sciences
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• v.45 no.2
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• pp.126-133
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• 2019

Objectives: In this study, a nine-stage cascade impactor was used to collect dust, and the concentration of $PM_{2.1}$ & $PM_{10}$ and alveolar deposition ratio were investigated. Methods: This study was conducted at Kunsan National University from May to June 2016. A nine-stage Cascade Impactor was used to analyze the concentrations of fine and ultrafine dust and to estimate the alveolar deposition rate by particle size of atmospheric dust particles. The pore size of each stage of the collector used in this study gradually increased from F to 0, with the F-stage as the last stage. Results: The mass fraction of PM showed a bimodal distribution divided into $PM_{2.1}$ & $PM_{10}$ based on $2.1-3.1{\mu}m$. The average mass fraction of particulate matter in the range of $2.1-3.1{\mu}m$ was 44%, and the area occupied by $PM_{2.1}$ was similar. Therefore, the Gunsan area is considered to be a region where there are similar effects from anthropogenic and natural sources. Conclusion: Dust collecting efficiency increased with the stage of collecting fine dust, and the efficiency of collection was very low at the stage of collecting ultra-fine dust. The seasonal overall efficiency of the Cascade Impactor was 44% in spring and 37.4% in summer, and the average overall efficiency was 40.7%. The alveolar deposition rate of $PM_{2.1}/PM_{10}$ during the sampling period was estimated to be about 75% deposited in the alveoli.