• Atmosphere
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• v.14 no.4
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• pp.3-18
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• 2004

Neglecting the vertical transport from the surface, most of the previous studies on the long-range transport of pollutants have only considered the horizontal transport caused by the free atmosphere wind. I used a three dimensional numerical model, MM5 (The fifth generation Penn State Univ./NCAR Mesoscale Model) for the simulation of vertical transport of pollutants and investigated the mechanism of the vertical transport of atmospheric pollutants between planetary boundary layer(PBL) and free atmosphere by fronts. From the three dimensional simulation of MM5, the amount of pollutants transport from PBL to free atmosphere is 48% within 18 hour after the development of front, 55% within 24 hour, and 53% within 30 hour. The ratios of the vertically transported pollutant for different seasons are 62%, 60%, 54%, and 43% for spring, summer, fall, and winter, respectively. The most active areas for the vertical transport are the center of low pressure and the warm sector located east side of cold front, in which the strong upward motion slanted northward occurs. The horizontal advection of pollutants at the upper level is stronger than at the lower level simply because of the stronger wind speed. The simulation results shows the well known plum shape distribution of pollutants. The high concentration area is located in the center and north of the low pressure system, while the second highest concentration area is in the warm sector. It is shown that the most important mechanism for the vertical transport is vertical advection, while the vertical diffusion process plays an important role in the redistribution of pollutants in the PBL.

• Asian Journal of Atmospheric Environment
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• v.11 no.4
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• pp.217-234
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• 2017

Indoor air pollutants can cause severe health problems, specifically in terms of toxicological impacts on human. Every day, a complex mixture of many air pollutants is emitted from various sources and subject to atmospheric processes that can create varied classes of pollutants such as carboxylic acids, aldehydes, ketones, peroxyacetyl nitrate, and hydrocarbons. To adhere to indoor air quality standards, a number of techniques such as photocatalytic oxidation of various volatile organic compounds (VOCs) have been employed. Among these techniques, titania ($TiO_2$) based photocatalytic reactions have proven to be the best benchmark standard approach in the field of environmental applications. Over the last 45 years, $TiO_2$-based photocatalytic reactions have been explored for the degradation of various pollutants. This review discusses the indoor air quality profile, types of indoor pollutants, available indoor air cleaning approaches, and performance of $TiO_2$-based catalysts. Finally, we have presented the perspectives on the progress of $TiO_2$ induced photocatalysis for the purification of indoor air.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.1
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• pp.33-46
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• 2004

Air pollutants were measured eight times from June 1999 to June 2002 on regular ferries cruising across the Yellow Sea between Incheon in Korea and Qingdao or Tianjin in China. PM$_{10}$ and PM$_{2.5}$ were measured as particulate matters and SO$_2$, CO, and NO$_{x}$ were measured as gaseous pollutants. On each route, sampling was made, starting two hour after departure and ending two hour before arrival. Low concentrations of gaseous pollutants that were not much varied according to sampling period and location revealed that atmosphere over the sea was not directly affected by anthropogenic emissions. However, concentrations of fine particles were generally higher than those measured at Deokjeok Island, 50km west of the western seashore, at similar periods. It was believed that considerable influence of China in the form of secondary pollutants was exerted over the sea.a.a.a.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.1
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• pp.93-100
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• 1993

This study was carried out to investigate the relationship between the traffic signal systmes and the air pollutants emitted by the motor vehicles at Kangnam Intersection. One of the most important measures of effectiveness (MOE) in traffic studies is the delay to vehicles in the system. Delay represents indirect costs to the motorist in terms of time loss and a direct cost in terms of fuel consumption during idling. The results of TRANSYT-7F modeling was correlated among delay, fuel consumption and total travel tiem. Air pollutants emission rate can be calculated by the results of modeling and the Korean type emission factor. As expected the highest emissions, for air pollutants, are observed during the morning rush hours (07 : 00-10 : 00). For better results of modeling, the TRANSYT-7F model needs to modify for the Korean type of traffic model. The results of this study indicate that the variation of air pollutants emission rates were closely related to the traffic signal system.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.1
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• pp.13-23
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• 2003

A local wind model and a three dimensional local environmental model including advection, diffusion, deposition. and photochemical reactions were performed at Gwangyang Bay, Korea, to predict air flow and air pollutants concentrations. A large grid was used, and nesting method was employed for small grid calculation. From the meterological module simulation, we were able to reproduce local wind characteristics such as sea/land winds and mountain/valley winds simulation at Gwangyang Bay. In addition, the concentration module showed high concentration regions at Yosu industrial complex, Gwangyang steel company. and Container anchor. It was also seen that air pollutants were dispersed by sea/land winds. A comparison between the measurement and the prediction of sulfur dioxide and nitric oxide, which are relatively low-reacted pollutants, was performed. However, the measured nitrogen dioxide and ozone concentrations were higher than the simulated ones. Particularly, ozone concentration between 8 a..m. and 8 p.m. agreed well, but the measured ozone during the rest of time were generally higher.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.5
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• pp.587-598
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• 1999

In recent years emissions of pollutants from ship sources, especially NOx and SOx, is controlled by IMO(International Maritime Organization). The emissions of pollutants from ship sources in Pusan is considerably large, because the number of ship's coming and going in Pusan port is larger than that of other ports in Korea. Since Pusan is under the strong influence of land-sea breezes, pollutants emitted from ship sources will be transported into the inland. Control of emissions from ship sources is required to devise effectively the policy of air quality management in Pusan. Therefore this paper considered the present condition of total pollutant sources and emission characteristics including in coastal urban area.

• International Journal of Contents
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• v.18 no.1
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• pp.17-26
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• 2022

With the acceleration of urbanization and industrialization, air pollution has become increasingly serious, and the pollution control situation is not optimistic. Climate change has become a major global challenge faced by mankind. To actively respond to climate change, China has proposed carbon peak and carbon neutral goals. However, atmospheric pollutants and meteorological factors that affect air quality are complex and changeable, and the complex relationship and correlation between them must be further clarified. This paper uses China's 2013-2018 high-resolution air pollution reanalysis open data set, as well as statistical methods of the Pearson Correlation Coefficient (PCC) to calculate and visualize the design and analysis of environmental monitoring big data, which is intuitive and it quickly demonstrated the correlation between pollutants and meteorological factors in the temporal and spatial sequence, and provided convenience for environmental management departments to use air quality routine monitoring data to enable dynamic decision-making, and promote global climate governance. The experimental results show that, apart from ozone, which is negatively correlated, the other pollutants are positively correlated; meteorological factors have a greater impact on pollutants, temperature and pollutants are negatively correlated, air pressure is positively correlated, and the correlation between humidity is insignificant. The wind speed has a significant negative correlation with the six pollutants, which has a greater impact on the diffusion of pollutants.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.5
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• pp.574-580
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• 2013

Green technology encompasses a growing group of methods and materials, from techniques for generating energy and alternative resources to non-toxic cleaning products. Green technology is expected to solve current problems in atmospheric environment such as climate changes due to green house gases and hazardous air pollutants. This paper provides a review on the status of green technology and policy guidelines in Korea as well as the green technology for air pollutants. It presents the R&D projects and future direction in atmospheric environment, and the green technology in mobile source air pollution. Emerging green technology contributes to sustainable growth and development of atmospheric environmental industry for better air quality.

• Design & Manufacturing
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• v.15 no.2
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• pp.49-55
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• 2021

In this study, CALPUFF, a three-dimensional atmospheric diffusion model, was used to predict the degree of influence of pollutants generated during clean center operation on surrounding areas. To drive the CALPUFF model, CALMET, a weather field calculation model, was used. Due to the influence of the wind field, air pollutants from the Clean Center diffused in the southeast direction, increasing the distribution area. SOx satisfies atmospheric environmental standards with an annual average value of 0.02 ppm or less NOx satisfies atmospheric environmental standards with an annual average value of 0.03 ppm or less. Dust (PM-10) satisfies atmospheric environmental standards with an annual average value of 50㎍/m³ or less and 24 hours average value of 100㎍/m³ or less. CO satisfies atmospheric environmental standards with an 8 hours average value of 9 ppm or less and an 1 hour average value of 25 ppm or less.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.3
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• pp.177-190
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• 1998

The concentrations of air pollutants In large cities such as Pusan area have been increased every year due to the increasing of fuels consumption at factories and by vehicles as well as the gravitation of the population. In addition to the pollution sources, time and spatial variation of air pollutants concentration and meteorological factors have a great influence on the air pollution problem. Especially , its concentration is governed by wind direction, wind speed, precipitation, solar radiation, temperature, humidity and cloud amounts, etc. In this study, we have analyzed various data of meteorological factors using typical patterns of the air pressure to investigate how the concentration of air pollutants is varied with meteorological condition. Using the relationship between meteorological factors (air temperature, relative humidity, wind speed and solar radiation) and the concentration of air pollutants (SO2, O3) , experimental prediction formulas for their concentration were obtained. Therefore, these prediction formulas at each meteorological factor in a pressure pattern may be roughly used to predict the air pollutants concentration and contributed to estimate the variation of its value according to the weather condition in Pusan city.