• Journal of Korean Society for Atmospheric Environment
• /
• 제11권E호
• /
• pp.23-29
• /
• 1995

산업 도시 부산에서 관측된 기상자료와 대기오염 자료를 이용해 대기오염과 대기투과도의 상호 관계를 연구하였다. 부산에서 대기오염에 의한 대기투과도를 예측하는데 경험적인 모델을 구축하기 위해 여러 기상 요소와 대기오염을 사용하였고, 이 결과를 Yamamoto et al.(1968)에 의한 대기투과도 계산 방법과 비교하였다. 그 결과, 두 방법에 의한 결과는 좋은 상관을 나타내었다. 따라서 본 연구에 의해 제시된 대기오염의 모수화는 부산에서 대기투과도와 직달일사량을 신뢰성 있게 예측하는 하나의 방법이라 생각된다. Relationship between atmospheric aerosol transmissivity and air pollution was analyzed using observed data in a large industrial city, Pusan, Korea. The atmospheric aerosol transmissivity predicted by method of present study in Pusan was assessed by the method of Yamamoto et al.(1968) in order to set up an empirical model to predict the transmissivity using the various meteorological parameters and air pollution. As a result, good correlation between these tow method re observed. Thus, it is possible to conclude that the parameterization of air pollution suggested by this study is another method to give reliable estimate of atmospheric aerosol transmissivity and direct solar irradiance in Pusan.

• Wind and Structures
• /
• 제20권1호
• /
• pp.59-74
• /
• 2015

A coupled model system for Wind Resource Assessment (WRA) was studied. Using a mesoscale meteorological model, the Weather Research and Forecasting (WRF) model, global-scale data were downscaled to the inner nested grid scale (typically a few kilometers), and then through the coupling Computational Fluid Dynamics (CFD) mode, FLUENT. High-resolution results (50 m in the horizontal direction; 10 m in the vertical direction below 150 m) of the wind speed distribution data and ultimately refined wind farm information, were obtained. The refined WRF/FLUENT system was then applied to assess the wind resource over complex terrain in the northern Poyang Lake region. The results showed that the approach is viable for the assessment of wind energy.

• 한국농림기상학회:학술대회논문집
• /
• 한국농림기상학회 2011년도 학술발표회
• /
• pp.50-50
• /
• 2011

• 한국환경과학회:학술대회논문집
• /
• 한국환경과학회 2019년도 정기학술대회 발표논문집
• /
• pp.87-87
• /
• 2019

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2004년도 추계학술대회
• /
• pp.1134-1139
• /
• 2004

Recently, development of flame control scheme has been hot issues in the combustion engineering. It has been held that flame shape can be controllable by pressure inside combustor. The influence of combustor atmospheric pressure on flame shape was investigated in the present study. The flame shape, flammable limit, flame temperature and nitric oxide emission were measured as functions of combustor atmospheric pressure and equivalence ratio. The reaction region became longer and wider with decreasing combustor atmospheric pressure by direct photography, hence reduction of blow off limit. This tendency was also observed in the mean flame temperature distribution. Nitric oxide emission decreased with decreasing combustor atmospheric pressure. Low NOx combustion is ascribed to wide-spread reaction region in the low atmospheric pressure condition. These results demonstrate that flame shape and nitric oxide emission can be controllable with combustor atmospheric pressure.

• 한국대기환경학회:학술대회논문집
• /
• 한국대기환경학회 1998년도 한국대기보전학회 춘계학술대회 요지집
• /
• pp.176-178
• /
• 1998

• Journal of Radiation Protection and Research
• /
• 제41권3호
• /
• pp.260-267
• /
• 2016

Background: This study analyzes the differences in the annual averaged atmospheric dispersion factor and ground deposition factor produced using two classification methods of atmospheric stability, which are based on a vertical temperature difference and the standard deviation of horizontal wind direction fluctuation. Materials and Methods: Daedeok and Wolsong nuclear sites were chosen for an assessment, and the meteorological data at 10 m were applied to the evaluation of atmospheric stability. The XOQDOQ software program was used to calculate atmospheric dispersion factors and ground deposition factors. The calculated distances were chosen at 400 m, 800 m, 1,200 m, 1,600 m, 2,400 m, and 3,200 m away from the radioactive material release points. Results and Discussion: All of the atmospheric dispersion factors generated using the atmospheric stability based on the vertical temperature difference were shown to be higher than those from the standard deviation of horizontal wind direction fluctuation. On the other hand, the ground deposition factors were shown to be same regardless of the classification method, as they were based on the graph obtained from empirical data presented in the Nuclear Regulatory Commission's Regulatory Guide 1.111, which is unrelated to the atmospheric stability for the ground level release. Conclusion: These results are based on the meteorological data collected over the course of one year at the specified sites; however, the classification method of atmospheric stability using the vertical temperature difference is expected to be more conservative.

• 한국대기환경학회지
• /
• 제21권2호
• /
• pp.169-178
• /
• 2005

A critical component of air pollution modeling is the representation of atmospheric flow fields within a model domain, since an accurate air quality simulation requires an accurate portrayal of the three-dimensional wind fields. The present study investigated data assimilation using surface observational data in the complex coastal regions to simulate a realistic atmospheric flow fields. Surface observational data were categorized into three groups (Near coastal region, Far coastal region 1, Far costal region 2) by the locations where the sites are. Experiments were designed according to the location of observational stations and MM5/CALPUFF was used. The results of numerical simulation of atmospheric flow fields are used as input data for CALPUFF which predicts dispersion fields of air pollutants. The result of this study indicated that data assimilation using data in the far coastal region 2 provided an attractive method for generating realistic meteorological fields and dispersion fields of air pollutants in Gwangyang area because data in the near coastal region are variable and narrow representation.

• 한국대기환경학회지
• /
• 제12권2호
• /
• pp.189-198
• /
• 1996

Mercury (Hg) is ubiquitous throughout the earth's atmosphere. The uniqueness of its atmospheric geochemistry is well-known with the high environmental mobility and relatively long atmospheric residence time (c.a., 1 year) associated with its high chemical stability. Despite a growing recognition of the environmental significance of its global cycling, the prexisting Korean database for atmospheric Hg is extremely rare and confined to a number of concentration measurements conducted under relatively polluted urban atmospheric environments. To help activate the research on this suvject, an in-depth analysis on the current development in the measurements of atmospheric mercury and the associated fluxes has been made using the most using the most updated data ests reported worldwide. As a first step toward this purpose, the most reliable techniques commonly employed in the measurements of its concentration in the background atmosphere are introduced in combination with the flux measurement techniques over soil surface such as: dynamic enclosure (or field flux chamber) method and field micrometeorological method. Then the results derived using these measurement techniques are discussed and interpreted with an emphasis on its mobilization across the terrestrial biosphere and atmosphere interface. A unmber of factors including air/soil temperature, soil chemical composition, soil water content, and barometric pressure are found out to be influential to the rate and amount of such exchange processes. Although absolute magnitude of such exchange processes is insignificant relative to that of the major component like the oceanic environment, this exchange process is thought to be the the predominant natural pathway for both the mobilization and redistribution of atmospheric Hg on a local or regional scale.

• Asian Journal of Atmospheric Environment
• /
• 제5권3호
• /
• pp.172-180
• /
• 2011

The transfer of microorganisms is important process for ecosystems. Microorganisms in dryland can transport itself to wetland through atmospheric diffusion, but only few papers reported about the atmospheric bioaerosol present over dryland. We carried out the direct sampling using a tethered balloon over Dunhuang City, China's northwestern dryland. Bioaerosols were collected using a tethered balloon with a bioaerosol collector at 820 m above the ground (1,960 m above the sea level) around noon on August 17, 2007. The bioaerosols were cultured after the collection at Dunhuang Meteorological observatory. Two strains of molds were isolated using the Nutrient agar medium. About 400-bp 18S rRNA partial sequences were amplified by PCR and determined afterwards. The results of a homology search by 18S rRNA sequences of isolates in DNA databases (GenBank, DDBJ, and EMBL) and an observation of the form revealed that two bioaerosols in the convective mixed layer over Dunhuang City were Cladosporium sp. and Aspergillus sp.