• Journal of the Korean Institute of Gas
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• v.1 no.1
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• pp.73-80
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• 1997

This study was performed to develop the dispersion modeling methodology for quantitative prediction of the hazard distance or toxic buffer distance by comparing 10-min average, 30-min average, and 1-hr average maximum ground-level concentration with $Cl_2$ regultaion concentration, IDLH and ERPG-3 concentration for hazardous toxic gas, $Cl_2$ releases from the storage tank of the chemical plant facilities. For this dispersion modeling, the source term model, dispersion model, meteorological and topographical data are incorporated into the SuperChems model, and then the effects of the atmospheric stability, wind speed, and surface roughness length changes on the maxum ground-level concentration were estimated.

• Journal of Korean Society for Atmospheric Environment
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• v.2 no.2
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• pp.19-30
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• 1986

This study was performed to develop a long-term air pollution dispersion model based on CDM program for use in the personal computer. The model CDM.PC, developmented for use of this study, simplified the plum equation of point pollution source in a windy state and sindless state. We used the classified 8 class stability, 16 wind direction and 4 class wind speed for the computer input climatological data. The plum rise equation is applied for CONCAWE's equation above 2,000 Kcal/sec of the exhaust calorie and Moses-Carson's equation below 2,000Kcal/sec at windy state, and Brigg's equation at calm. The time required is 200 minutes for drawing the air pollution contour for treating ten stacks under the above-stated conditions. It is the weakness of using personal computer that the operation time is longer than a large-size computer. But it strength is that the personal computer is used widely. To compare the treatment results of CDM.PC with TCM, we comfirmed that the shape of $SO_2$ pollution contour is similar but the concentration distribution is quite different because of characteristics of each models. Estimated and measured $SO_2$ concentration were similar, namely, Cest/Cob ratio of CDM.PC and TCM were respectively $0.96 \pm 0.25 (mean\pmS.D)$ and $1.08\pm0.26$.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.2
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• pp.123-135
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• 1997

An air pollutant emission inventory system for the input preparations of photochemical dispersion model was developed. Using the system, anthropogenic emissions as well as biogenic emissions in the Seoul metropolitan area were calculated. Anthropogenic emission by fuel combustion using regional cosumption data, and the laundries and so forth was estimated. The biogenic emission was estimated based upon meteorological data and the distribution of land use type in the study area. The anthropogenic emission of pollutants was highest in Seoul, and the second highest in Inchon. TSP and $SO_2$ were found large quantities during the winter due to increased consumption of heating oil. NOx and THC were emitted without seasonal variation. Among biogenic emissions, PAR was very common while NO was the least common. PAR, OLE, and ALD2 were emitted in large volumes in coniferous forest areas, while ISOP was emitted in deciduous forest areas. Generally, most biogenic emissions increased during daytime, and peaked between oen and two o'clock. Because of strong solar radiation, emission during the summer was high. Biogenic NO emissions were found to be lower compared to anthropogenic emissons, and other VOC was indicated relatively high. In the study area, among biogenic emissions PAR was found to be 3 times, OLE 8 times,and ALD2 12 times more common than among anthropogenic emissions.

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.E
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• pp.357-370
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• 1994

This paper introduces an Eulerian long- range transport model coupled with a mesoscale atmospheric model. The model has been applied to the simulation of tracer distribution during two cases of Cross Appalachian Tracer Experiment (CAPIEX). Meteorological fields are Predicted by CSU RAMS with four-dimensional assimilation and tracer transport is computed from an Eulerian dispersion model. The atmospheric model with a four-dimensional assimilation has produced meteorological fields that agree well with observation and has proved its high potential as a generator of meteorological data for a long-range transport model. The Present transport model Produces reasonable simulations of observed tracer transport although it was partially successful in the case with complicated structure in observed concentration. Model with Bott's 2nd-order scheme performs as well as that with Bott's 4th-order scheme and increased explicit horizontal diffusivity. Diagnosis of the model results indicates that the Present long-range transport model has a good potential as a framework for the acid deposition model with detailed cloud and chemical processes.

• 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.15 no.5
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• pp.687-696
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• 1999

Characteristics of four publicly-available accidental release models, ALOHA, SLAB, HGSYSTEM, and DEGADIS, are compared. These models are world-widely used and recently recommended by the Chemical Dispersion and Consequence Assessment(CDCA) Working Group of the United States as models applicable to generally broad safety-basis documentation applicatons. Four release scenarios are assumed by referring to the usage and storage conditions of toxic substances in the field as well as the USEPA model guideline(1993). Sensitivity of impact radius by varying meteorological conditions is tested in typical and worst-case meteorological conditions. The results show that ALOHA generally gives conservative estimates and the results from HGSYSTEM are sensitive to variations in meteorological conditions.

• Journal of Korean Society for Atmospheric Environment
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• v.2 no.2
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• pp.31-40
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• 1986

Motor vehicle related air pollution has become more serious because of rapid increase of number of cars, specially in the urban area. The increase trend seems to be accelerated, however, the fact is that road conditions, parking facilities and traffic control systems are far behind coping with this situation. In spite of the lack of related basic data, urban transportation planning (UPT) and air pollution dispersion models were applied to predict air pollution level. In standard UPT model, trip generation, distribution, modal split and network assignment were estimated by experimental equations and appropriate models. The air pollution level in the central business area was believed to be higher and it will increase continuously due to the increase of traffic demand. To meet this situation, air pollution problem should be considered as a part of integrated plannings of urban plans or transportation plans as well as more stringent motor vehicle emission standards, have to be enforced.

• Journal of Korean Society for Atmospheric Environment
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• v.7 no.3
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• pp.150-155
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• 1991

The Gaussian models were selected as the reference models for the study. During the study of the model verification in the Ulsan Industrial Complex, the accuracy and limitation of models were assessed. The correlation coefficients of the observed and the predicted values for CDM 2.0 and TCM2B were ranged from 0.57 to 0.73 and from 0.72 to 0.86, respectively. And there were relatively large discrepancies between the predicted and predicted and the measured concentrations for several locations. Therefore, the Gaussian models should be used with careful discretion to apply the urban area in Korea.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.137-138
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• 2003

한국 환경부가 지원하는 대기오염확산모델 SKYi는 통합환경관리의 일환으로서 대기오염배출규제강화와 미래 대기질의 예측뿐만 아니라 환경관리의 입법적인 수행을 목적으로 개발 중에 있다. SKYi는 기상과 배출 그리고 지형에 대한 전처리과정의 서브프로그램과 연결되는데, 본 연구는 기상전처리과정의 모듈 SKYME 개발에 중점을 둔다. 이는 기상전처리모듈에서 산출된 혼합고도와 같은 기상인자가 대기오염확산의 물리적인 특성으로서 효율적인 대기오염농도예측에 중요한 역할을 하기 때문이다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.181-182
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• 2000

경제성장과 더불어 환경에 대한 일반인들의 관심이 증가되어 기존의 환경기준 대상 오염물질 위주의 대기질 평가 외에 소음이나 악취 등의 감각공해에 대한 체계적인 연구가 필요하게 되었다. 악취에 의한 오염은 인간이 오감을 통해서 느끼는 정신적 피해의 하나로 청각을 통한 소음문제, 미각을 통한 음용수문제, 시각을 통한 경관의 문제 등과 같은 감각공해 중 대표적인 오염현상으로 생활환경의 쾌적성과 밀접한 관계를 갖고 있다. (중략)