• 한국대기환경학회지
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• 제13권2호
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• pp.137-145
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• 1997

To predict the effects of air pollutant in the coastal region, we have developed the air pollutant model, the reaction model and the deposition of NO, $NO_2, and O_3$. And the numerical model of air pollutant concentration employed the nested technique to calculate with the higher resolution for the area. The nested technique used two grid systems, one for the large scale calculating region with the coarse mesh grid (CMG) and the other for the small scale region with the fine grid (FMG). In other to prove the validity of the simulation model the calculations were conducted for the present situation. The results of them reasonably agree with the observed data and proved the validity of the model.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.187-190
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• 2007

Nowadays, with urban railway vehicles, refrigeration has been used for a long time as an air conditioner including a heating apparatus and a ventilator. Regarding saveenergy, there are lots of researches continually on the refrigeration field to reduce the parts' weight, improve the parts' efficiency and make good looking design of air conditioners. Moreover, we are able to see the recent achievement of the researches. As a result, through this research we improve the quality of inner air with the urban railway system and make a domestic HVAC system by technical development of high capacity air conditioner and the principal parts.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.218-221
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• 2007

Nowadays, with urban railway vehicles, refrigeration has been used for a long time as an air conditioner including a heating apparatus and a ventilator. Regarding saveenergy, there are lots of researches continually on the refrigeration field to reduce the parts' weight, improve the parts' efficiency and make good looking design of air conditioners. Moreover, we are able to see the recent achievement of the researches. As a result, through this research we will improve the quality of inner air with the urban railway system and make a domestic HVAC system by technical development of high capacity air conditioner and the principal parts.

• 한국대기환경학회지
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• 제15권3호
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• pp.281-289
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• 1999

A new E-$\varepsilon$ turbulence numerical model is proposed for analysing the turbulent air flow field within are urban street canyon. In this model the equations of eddy viscosity and energy dissipation ae reformed by considering the Kolmogorov time scale and streamline curvature effect. Application results of the new E-$\varepsilon$ model have been compared with those of standard E-$\varepsilon$ model and Yang and Shih's one, which are commonly used ones in engineering fields, and with field experiment results of DePaul and Sheih. The new model appears to be generally superior to other both models in the prediction of an air flow field within street canyon.

• 도시과학
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• 제9권2호
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• pp.13-20
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• 2020

The Recently, several countries have been affected by respiratory diseases, resulting in renewed research interest in their prevention and control. One such example was the 2015 outbreak of Middle East Respiratory Syndrome (MERS) in South Korea and COVID-19. In this study, we performed experiments and simulations based on concentration decay using CO2 as the tracer gas to elucidate the pollutant-removal efficiency for different inlet and exhaust locations and outdoor air-supply ratios. The wall inlet exhibited a higher pollutant-removal efficiency, owing to the upward movement of the air from the lower zone to the upper one. In conclusion, it is recommended that a total air-conditioning plan for isolation rooms be established as well as efficient system operation for pollutant removal and air-flow control to prevent the transmission of infections from the patients to others.

• 한국환경과학회지
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• 제20권4호
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• pp.465-482
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• 2011

To preserve atmospheric environment of urban areas, it needs to create urban space considering air pollution sources and natural and geographical properties such as wind circulation. According to this study could examine climate and environmental characteristics of Daegu and accordingly suggest a climate map in urban environment and an "advice map" in urban planning. The urban area(area paved with asphalt and concrete) of Daegu has increased by more than five times since 1960. In addition, the analysis of thermal environment through satellite data shows that the surface temperature between a place paved with artificial structures and a farmland shows $10{\sim}20^{\circ}C$ difference during the daytime in the summer. Regarding the parks inhibiting the heat island of a city have the small area of trees, and the road paved with concrete is wide so that they hardly serve as the source of heat absorption. As Apsan is located to the south of Daegu and Palgonsan to the north and Daegu has east high west low type, mountain wind from mountains in the south and north passes a city and delivers heat and air pollutions at night. In the west of Daegue, there is the poorest environment and industrial facilities and environmental basic facilities are mostly located, so large residential complexes that are being built around the industrial facilities as if they set up a folding screen and therefore the poor environment is increasingly worse.

• 대한원격탐사학회지
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• 제27권3호
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• pp.339-351
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• 2011

This study investigates the potentials of satellite, ground measurement data, and geo-spatial information within an urban area for the mapping of the Urban Environmental Quality (UEQ) parameters. The UEQ indicates a complex and various parameters resulting from both human and natural factors, which are greenness, climate, air pollution, the urban infrastructure, and etc. Multi-spectral remote sensing data from the Landsat ETM and TM sensors for the mapping of air pollution by the Haze Optimized Transform (HOT) technique, Urban Heat Island (UHO using the emissivity-fusion method in Seoul from 2000 to 2006 in fine resolution (30m) were analyzed for the estimation of UEQ index. Although the UHI values are similar ($8.4^{\circ}C{\sim}9.1^{\circ}C$) during these years, the spatial coverage of "hot" surface temperature (> $24^{\circ}C$) significantly increased from 2000 to 2006 due to the rapid urban development. Furthermore, high correlations between vegetation index and land surface temperature were achieved with a correlation coefficients of 0.85 (2000), 0.81 (2001), 0.84 (2002), and 0.89 (2006), respectively. It was found that the proposed method was successfully analyzed spatial structure of the UEQ and the scenarios of the best and worst areas within the city were also identified. Based on the quantifiable fine resolution satellite image parameters, UEQ can promote the understanding of the complex and dynamic factors controlling urban environment.

• 한국환경보건학회지
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• 제39권2호
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• pp.159-165
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• 2013

Objective: This study was carried out in order to estimate atmospheric Polychlorinated Biphenyls (PCBs) concentrations using pine needles as a passive air sampler (PAS) in urban, semi-rural and rural regions. Methods: One-year old pine needles were collected to analyze their PCBs concentrations ($C_p$, pg/g dry) at the end of December. PCBs concentrations in ambient air ($C_a$, $pg/m^3$) were calculated with the $logK_{oa}-log(C_p/C_a)$) model. Results: PCBs concentrations in ambient air ($C_a$) were high in the order of urban, semi-rural and rural regions. The lower-chlorinated PCBs showed a higher concentration in ambient air. However, the distribution of PCBs congeners was similar in all three regions. Correlation between $C_a$ and the population density of the three regions was significant ($R^2$=0.9834, p<0.001). Conclusions: It was concluded that although the production and use of PCBs was banned in the1970s, PCBs are currently being produced unintentionally by human activities.

• 한국환경복원기술학회지
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• 제12권1호
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• pp.44-51
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• 2009

In order to determine air temperature difference by canopy layer in the forest, air temperatures were observed at Seolleung Park, Gahngnam-ku, Seoul. from November 9, 2007 to November 8, 2008 by 10 minute interval. The data were analyzed in terms of diurnal variation based on annual and monthly temperature difference. Using calm, less cloudy and no rainy weather data, average air temperature difference between forest and grass was observed as $0.8^{\circ}C$. The maximum air temperature difference was observed at 22:10, 23:20, 23:30 and 23:40 by $2.13^{\circ}C$ and the minimum one observed at 13:00 by $-0.84^{\circ}C$ in diurnal variation. The maximum temperature difference occurred at 19 : 50 on September by $3.67^{\circ}C$, Overall the air temperature in the forest was higher than that of grass at night and lower in midday.

• 한국안전학회지
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• 제11권2호
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• pp.102-108
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• 1996

Urban air pollution has been gradually increasing by the increase of population and vehicles recently. There are shown larger effects of air pollution in Incheon city which has more than 2 million people and has heavy holding amounts ratio of transportation vehicles as compared with other cities. However, it is very difficult to predict the air quality condition of their moving pollutants. Therefore, in this study air pollution measuring model was designed to estimate the air pollution level by line sources(transprtation vehicles ) of air pollutants and to detect the $NO_x$ emission amounts in ordinary times, and it became clear that it is functionally operative.