• Journal of Korean Society for Atmospheric Environment
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• v.9 no.1
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• pp.44-50
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• 1993

The suspended particulate matters had been collected by a cascade impactor having 9 size fragnated stages for 2 years (Dec. 1989 to Nov. 1991) in Kyung Hee University-Suwon Campus. The particulate matters were then collected on each stage by membrane filters. The weight concentration on each stage was estimated by a microbalance and further chemical element concentrations were determined by an XRF system. The study focused on developing of a receptor model using the TTFA (target transformation factor analysis) to apportion aerosol mass with the 30 ambient data sets. Each data set consists of the 8 size-ranged subdata sets characterized by 13 element variables. Even though a couple of sources could not be identified, three to five sources were extracted from each aerosol size-range, and then 9 statistical source profiles were generated. Finally, source contribution of particulate matters on each size-range could be estimated in Suwon area.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.5
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• pp.450-458
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• 2009

The range-dependent overlap factor of a lidar system can be determined experimentally if a Raman backscatter signal by molecule is measured in addition to the usually observed elastic backscatter signal, which consists of a molecular component and a particle component. The direct determination of the overlap profile is presented and applied to a lidar measurement according to variation of telescope field-of-view and distance between telescope and transmitting laser. The retrieval of extinction coefficient by Raman method can generate high errors for heights below planetary boundary layer if the overlap effect is ignored. The overlap correction method presented here has been successfully applied to experimental data obtained in Gwangju, Korea.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.4
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• pp.295-302
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• 1993

The nature of the cavity region and dispersion around trianglular ridge was investigated using model. The artifical neutral boundary layer was simulated in water channel. Two dimensional trianglar ridges, having height of 1.2 cm and various width were placed normal to the flow. Mean velocity with many dimensionless parameters were measured and compared with wind tunnel results by other studies. Using vorticity generator and roughness, the neutral boundary layer was well represented by the water channel. concentration patterns resulting from dye source placed 0.2 cm height above were examined. Narrower the trianglar ridge width resulted in increased amplification factor and the larges amplification factor was observed near downward top of the ridge.

• Journal of Korean Society for Atmospheric Environment
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• v.3 no.1
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• pp.55-64
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• 1987

Actual driving pattern of each motor vehicle type was measured and analyzed in Seoul area and vehicle emission rate was measured and traffic data were used to estimate vehicular emission factor and motor vehicle-related air pollutant emission. The analysis of contribution ratio of each vehicle type showed that LPG taxi's took 38.1% of total vehicular CO, gasoline passenger cars 37.5%, therefore, these cars are major sources of CO, gasoline passenger cars took 45.4% of total vehicular HC, motorcycles 25.3%, LPG taxi's 16.2%, so motorcycles can be said to play an important role in HC emission. For NOx, buses and trucks were thought to be major sources as buses took 36.8% and truck 26.4%. Diesel vehicles, on the other hand, took most $SO_2$ and particulate matter emission. Total emission from motor vehicles in Seoul was estimated to be 547 t/day of CO, 68t/day of HC, 163t/day of NOx, 18t/day of $SO_2$ and 19t/day of paticulate matter.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.6
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• pp.520-529
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• 2015

The ambient $PM_{2.5}$ samples were collected by $PM_{2.5}$ sampler from September 2010 to December 2012 at Daegu University, Gyeongsan. A total of 260 samples were collected and 27 species were analyzed by inductively coupled plasma, ion chromatography, and thermal optical reflectance methods. Factor analysis identified four sources such as biomass burning source/secondary aerosol source, soil source, industry source, and incinerator source/mobile source. Also, backward trajectories were calculated using HYSPLIT 4 (Hybrid single-particle lagrangian integrated trajectory) model and PSCF (Potential source contribution function) model was applied to identify the possible source locations of carbonaceous species and water soluble ions species. PSCF results showed that the possible source locations of most chemical constituents measured in Gyeongsan were the industrial areas in the eastern coast of China, northeast regions of China, the Gobi Desert, and east sea of Korea.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.3
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• pp.333-343
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• 2003

The aerosol ionic composition of P $M_{2.5}$ measured at Gosan, Jeju Island, Korea, for 4 years between March 1998 and February 2002 are presented and discussed. The annual mean concentration of non- sea-salt sulfate (nss -S $O_4$$^{2-}$) and ammonium (N $H_4$$^{+}$) ions are high (0.094 $\mu$eq/㎥, and 0.085 $\mu$eq/㎥, respectively). Also, nss-S $O_4$$^{2-}$ and N $H_4$$^{+}$ show high correlation (0.892). The concentrations of most ions are high in springtime. As the result of factor analysis, Gosan area mainly affected by sea-salt, anthropogenic species, and crustal species.ies.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.1
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• pp.26-36
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• 2014

The uncertainty assessment is important to improve the reliability of emission inventory data. The DARS (Data Attribute Rating System) have recommended as the uncertainty assessment technic of emission inventory by U.S. EPA (Environmental Protection Agency) EIIP (Emission Inventory Improvement Program). The DARS score is based on the perceived quality of the emission factor and activity data. Scores are assigned to four attributes; measurement/method, source specificity, spatial congruity and temporal congruity. The resulting emission factor and activity rate scores are combined to arrive at an overall confidence rating for the inventory. So DARS is believed to be a useful tool and may provide more information about inventories than the usual qualitative grading procedures (e.g. A through E). In this study, the uncertainty assessment for 2009 CAPSS (Clean Air Policy Support System) emission inventory is conducted by DARS. According to the result of this uncertainty assessment, the uncertainty for fugitive dust emission data is higher than other sources, the uncertainty of emission factor for surface coating is the highest value, and the uncertainty of activity data for motor cycle is the highest value. Also it is analysed that the improvement of uncertainty for activity data is as much important as the improvement for emission factor to upgrade the reliability of CAPSS emission inventory.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.2
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• pp.110-118
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• 2014

This paper addresses the fugitive emission factors of Reefer Container at use-phase and disposal-phase. The residual quantities and operation time of thirty nine Container were weighed, using a commercial recover of refrigerants to determine the emission factors at the use-phase. The emission factor at the disposal-phase, refrigerant is accomplished has not recycled, the residual rate was assumed that the emission factor. The average residual rate of thirty nine Container is determined to be $70.8{\pm}4.0%$. The emission factor at the use-phase is estimated to be $4.9{\pm}0.9%/yr$ in the case of using average age of 8.1 years and the average residual rate determined here. We estimate 162.7 g/yr for the average emission quantity of refrigerant per operating Container, while 2038.1 g for that per waste Container. Since the chemical compositions of refrigerant of waste Container were the same as those of new refrigerant, it is expected that the refrigerant recovered from waste Container can be reused for refrigerant.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.11a
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• pp.389-390
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• 2004

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.11a
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• pp.93-94
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• 2004