• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.2
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• pp.111-116
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• 2000

Transboundary air pollution has recently become an area of increasing scientific interest and political concern as countries are receiving air pollutants from their neighbors. In order to gain a better understanding of the long-range transport processes of air pollutants and the source-receptor relationships among neighboring countries, an atmospheric transport model coupled with a RAMS(Regional Atmospheric Modeling System) model was applied to the East Asia region during the entire month of January 1993. The scalar transport option of the RAMS model was used to calculate special atmospheric constituents such as trace gases or aerosols. The sulfate production in clouds and rainwater and its removal processes by dry and wet deposition were considered. The sulfate budget from source regions to receptor regions was estimated by analysing the source-receptor relationships. When a specific receptor site revealed a sulfate value higher than the sulfate concentration based on its own source origin, this was taken to indicate long-range transport from another source region. The contribution ratio from various source region was calculated. The contribution ratio of dry and wet deposition was higher on the main continent of the East region. Furthermore, the high deposition amounts were identified on the west coast of Korea and the East China Sea.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.2
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• pp.167-177
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• 1996

To investigate the source-receptor relationships aerosol model has been used to simulate the distribution behavior of the yellow sand. Data for meteorological fields were obtained by Meso-scale Analysis and Prediction Model System/Seoul National University (MAPMS/SNU) for five days (10-14 April 1988). To obtain the distributions of concentration of yellow sand,the aerosol model has been modified to allow quantifications of relative concentration distributions of yellow sand. Source regions of yellow sand were delineated by soil maps of China and emission rate as a function of wind stress(Westphal et al., 1987). Using 3-dimensional wind fields the backward trajectories from 3 receptor grids at the layer of .sigma. =0.95, 0.9, 0.85, 0.8 were calculated. In order to facilitate quantitative assessment of source-receptor relationships, it was assumed that the perturbations in along-trajectory and cross-trajectory proceed linearly with time, in accord with Gaussian distribution characteristics. On the basis of this assumption, the probability fields were calculated from every grid point with source strength 1. Using these probability fields and emission retes, the potential contributions of upstream sources along the trajectories were estimated. The results of this study indicate that the application of trajectory modeling is useful in investigating the quantitative relationship between source and receptor regions.

• Journal of Environmental Science International
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• v.3 no.4
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• pp.393-402
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• 1994

It is necessary to examine the source contributions and the relationship between a receptor and sources for the resonable controlling of air pollution level of suspended particulate matters. Therefore, in this study, profiles of sources contributing to the concentration of suspended particulate matters, were developed and CMB model was applied to obtain information of source contributions and feasibility of CMB model application. According to the propose of this study, twenty-seven chemical species such as the elements, anions, and total carbon of thirty-six PMl0 and TSP data sets sampled at the Pomch'on receptor site in Pusan for a 24-hr period from May to Aug. 1992, were analyzed and three (transportation, soil, marine) different source profiles were developed through the field measurement. Applying CMB model to transportation, soil, marine, the results of source contribution by CMB model showed that the case with TSP was more suitable for CMB model than that with PMl0. And the average contribution of transportation source to TSP and PMlo concentration at Pomch'on receptor was calculated as 90.66 ㎍/m3(64%) and 23.27 ㎍/m3(39%), resfiectively, which showed that the contribution by transportation was dominant. The validation of CMB model was performed by means of the results of contributions from marine source for the wind direction sectors.

• The Journal of the Korea Contents Association
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• v.19 no.3
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• pp.485-493
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• 2019

With the development of remote sensing technology, it becomes possible to measure the trace gas concentration by satellites, so the ministry of environment is executing 152.5 billion-won to develop the geostationary orbital environment monitoring satellite and ground segment. A variety of contents for the application to utilize environmental satellite has been sought to increase the benefits. This study is for the improvement the accuracy of emission inventories, to correct emission amount with top-down method using the satellite observing data instead of bottom-up method. Two methodologies to estimate $NO_2$ emission were analyzed, one is ignoring $NO_2$ transportation effect(method-1), and the other is considering transportation effect(method-2) with source-receptor relationship equation, and the results were compared. The methodology of this study can be applicable all components which are observed from satellites.

• Journal of radiological science and technology
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• v.41 no.5
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• pp.391-396
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• 2018

The purpose of this study was to compare and analyze the patient dose according to the distance between the X-ray tube focus and the image receptor, and to propose a new method for quantitatively evaluating the image quality. Using this quantitative evaluation method, the optimal distance for increasing x-ray image quality with low radiation dose was estimated between source and image receptor in Rib series radiography. Phantom images were obtained by changing the distance between focus and image receptor (100 cm and 180 cm). The patient radiation dose was estimated using entrance surface dose and dose area product. In order to evaluate image quality objectively, a non - reference image evaluation method was employed with paper and salt noise and Gaussian filter. As a result of this study, when the SID was changed from 100 cm to 180 cm, the entrance surface dose decreased by 4 ~ 5 times and the dose area product decreased by 3 times. In addition, there is no significant difference in image quality between of SID 180 cm and SID 100 cm. In conclusion, it was demonstrated that performing the rib series radiography at SID 180 cm is an optimal method to reduce the exposure dose and improve the image quality.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.04a
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• pp.660-661
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• 2008

• Journal of Korean Society for Atmospheric Environment
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• v.17 no.2
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• pp.147-155
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• 2001

ISCLT3 model was applied in Seoul metropolitan area to investigate the source-receptor relationships among 17 cities in the Kyonggi Province. For the purpose of the model simulation, emission rates of NO$_2$, SOx, and PM(sub)10 were prepared for grid scale with 1$\times$1 km, and receptors were located on every 2$\times$2 km grid. Meterological data for the last 10 years(88~97) were used as input data. According to our study, NO$_2$ concentration of the cities ranged from 10 to 45 ppb with the highest value appearing from Puchon city. The concentrations of SOx and PM(sub)10 concentrations fell in the range of 5~20 ppb and 20~70$\mu\textrm{g}$/㎥, respectively. It was also found out that air quality in one city can be affected greatly by the air pollutants originating from other cities.

• Journal of Environmental Science International
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• v.19 no.5
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• pp.591-605
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• 2010

This study were to simulate major criteria air pollutants and estimate regional source-receptor relationship using air quality prediction model (TAPM ; The Air Pollution Model) in the Seoul Metropolitan area. Source-receptor relationship was estimated by contribution of each region to other regions and region itself through dividing the Seoul metropolitan area into five regions. According to administrative boundary, region I and region II were Seoul and Incheon in order. Gyeonggi was divided into three regions by directions like southern(region III), northern(IV) and eastern(V) area. Gridded emissions ($1km{\times}1km$) by Clean Air Pollicy Support System (CAPSS) of National Institute of Environmental Research (NIER) was prepared for TAPM simulation. The operational weather prediction system, Regional Data Assimilation and Prediction System (RDAPS) operated by the Korean Meteorology Administration (KMA) was used for the regional weather forecasting with 30km grid resolution. Modeling period was 5 continuous days for each season with non-precipitation. The results showed that region I was the most air-polluted area and it was 3~4 times more polluted region than other regions for $NO_2$, $SO_2$ and PM10. Contributions of $SO_2$ $NO_2$ and PM10 to region I, II and III were more than 50 percent for their own sources. However region IV and V were mostly affected by sources of region I, II and III. When emissions of all regions were assumed to reduce 10 and 20 percent separately, air pollution of each region was reduced linearly and the contributions of reduction scenario were similar to those of base case. As input emissions were reduced according to different ratio - region I 40 percent, region II and III 20 percent, region IV and V 10 percent, air pollutions of region I and III were decreased remarkably. The contributions to region I, II, III were also reduced for their own sources. However, region I, II and III affected more regions IV and V. Shortly, graded reduction of emission could be more effective to control air pollution in emission imbalanced area.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.10a
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• pp.143-144
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• 2006

• Journal of Korean Ophthalmic Optics Society
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• v.8 no.2
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• pp.163-168
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• 2003

The eye sensitivity in the difference conditions of a light source intensity consists of two functions by the receptor of cone and rod according to a wavelength. We derived a distribution function of $P{\lambda}=A{\cdot}e^{-({\lambda}-{\lambda}_u)^2/2W^2}$ using a respond probability of the receptor of cone-rod for a photon. It was well applied for a CIE eye's sensitivity curve of a wavelength. When there is lens In front of eye, luminous efficiency should be corrected. Transmission light which permeate to depends on absorption wavelength, and relationship of final luminous efficiency's estimation method is expressed by multiplication of luminous efficiency and transmittance intensity of lens. $$Pf({\lambda})=T({\lambda}){\cdot}P({\lambda})$$. The theory was applied to photopic and scopic vision with brown color lens.