• 한국대기환경학회지
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• 제8권3호
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• pp.198-203
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• 1992

Theoretical predictions of the atmospheric equilibrium involving $HNO_3, NH_3 and NH_4NO_3$ were compared with atmospheric measurements of particulate nitrate$(NO_3^-)$, $HNO_3$ and $NH_3$ concentration by triple filter pack sampler and Andersen air sampler in Seoul from 8th to 11th Oct 1991. The measured $HNO_3-NH_3$ concentration product K was higher than equilibrium costant Kc calculated from thermodynamic data of $HN_4NO_{3(s)} -HNO_{3(g)} -NH_{3(g)}$. The cause of K is greater than Kc was the result of air pollution, partcicularly anthropogenic $NH_3$.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2010년도 춘계학술대회 논문집
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• pp.141-143
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• 2010

• 한국대기환경학회지
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• 제16권1호
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• pp.69-77
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• 2000

This paper summerizes the results of the first proficiency testing program for achieving the analytical quality assurance of anions and metal ions in air borne particles in Korea. This program covered the chemical testing of anions(Cl-, NO3-, SO42-) and metals(Fe, Pb, Zn) in qeueous solution. The exercies was conducted by the Measurement & Analysis Committee of Korean Society for Atmospheric Environment(KOSAE). Pilot lab. was Division of Chemical Metrology and Materais Evaluation in Korea Research Institute of Standards and Science(KRISS). A total of 11 laboratories participated in the program. Two samples of 100mL in low density polyehylene bottles were supplied to participating laboratories. The proficiency testing results were interpreted by two graphical methods, Youden polt and x-Charts(control chart).

• Computers and Concrete
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• 제16권5호
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• pp.775-793
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• 2015

Moisture transport in concrete in atmospheric environment was studied in this paper. Based on the simplified formula of the thickness of the adsorbed layer, the pore-size distribution function of cement paste was calculated utilizing the water adsorption isotherms. Taking into consideration of the hysteresis effect in cement paste, the moisture diffusivity of cement paste was obtained by the integration of the pore-size distribution. Concrete is regarded as a two-phase composite with cement paste and aggregate, neglecting the moisture diffusivity of aggregate, then moisture diffusivity of concrete was evaluated using the composite theory. Finally, numerical simulation of humidity response during both wetting and drying process was carried out by the finite difference method of partial differential equation for moisture transport, and the numerical results well capture the trend of the measured data.

• 한국환경과학회지
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• 제17권6호
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• pp.623-631
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• 2008

Many recent studies have concentrated upon the radiative effects of atmospheric aerosols. Though their scattering and absorption of radiation, aerosols can also induce some other important environment effects. In this study, new radiation code and aerosol data within Atmosphere General Circulation Model (AGCM) is used to assess the aerosol radiative forcing and to analyze relative climate effects. The new Kangnung National University AGCM Stratospheric-15 (KNU AGCM ST15) was integrated by using two sets of radiative effect of aerosols: CTRL as not a radiative effect of aerosols and AERO as a radiative effect of aerosols. Two cases show the difference of net shortwave radiation budget at top-of-atmosphere (TOA) is found to be about $-3.4Wm^{-2}$, at the surface (SFC) is about $-5.6Wm^{-2}$. Consequently the mean atmospheric absorption due to aerosol layer in global is about $2.2Wm^{-2}$. This result confirms the existence of a negative forcing due to the direct effect of aerosols at the surface and TOA in global annual mean. In addition, it is found that cooling over at the surface air temperature due to radiative effect of aerosols is about $0.17^{\circ}C$. It is estimated that radiative forcing of the net upward longwave radiation taken as the indirect effect of aerosol is much smaller than that of the direct effect as there is about $0.2Wm^{-2}$ of positive forcing both at TOA and at SFC. From this study, It made an accurate estimation of considering effect of aerosols that is negative effect. This may slow the rate of projected global warming during the $21^{st}$ century.

• 한국대기환경학회지
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• 제7권3호
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• pp.145-149
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• 1991

A one dimensiional cumulus cloud model has been developed for the investigation of temporal and altitudinal variation of trace gases and the wet deposition rates of sulfate for different simulation conditions. The results show that the dynamic field, liquid mixing ratios and the solubility of trace gases affect the distribution of trace gases and the droplet pH. Temporal variation of the predicted surface precipitation and sulfate deposition rates agree well with the field data.

• 한국대기환경학회지
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• 제19권2호
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• pp.205-216
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• 2003

We have gathered exposure data on ambient air quality level and investigated dose-response slope factors of air pollutants such as fine particle, HAPs (metals, VOCs, PAHs) and dioxins in Seoul. Theoretical mortality incidences were estimated from exposure to these pollutants. From the results, priorities were ranked in the order fine particle, metals, VOCs, dioxins and PAHs by ordinal scale, and the uncertainties relative to those risk estimates were described.

• 한국대기환경학회지
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• 제5권2호
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• pp.97-105
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• 1989

Recently, many studies on air quality prediction models have been performed to develope new ones. The purpose of the study is to obtain a method to predict $SO_2$ concentration simply in urban area using hour-to-hour meteorological data such as the wind speed, the incoming solar radiation, and the cloud coverages. The relationships between with speed and $SO_2$ concentrations are plotted in flgures. Predicted concentration curves are obtained for equation C=b/(1+au).

• 한국대기환경학회지
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• 제20권2호
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• pp.237-249
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• 2004

With the increasing concern over the air quality degradation, there are growing demands to accurately and precisely measure air quality. In this article, the general principles and approaches were described to help aid proper evaluation of air quality. In order to introduce the basic approaches for conducting field/laboratory experiments and for interpreting experimental data sets, we explained all the common methodologies involved and provided some insights into the desirable protocols for air quality measurements.

• 한국대기환경학회지
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• 제24권2호
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• pp.249-258
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• 2008

Historical emission data for 11 polychlorinated biphenyls (PCBs) and a regional multimedia environmental model, CoZMo-POP 2, were used to predict air concentrations and congener patterns in Korea. The total emission value for South Korea was allocated to sub-provinces and cities based on their population. The spatial distribution of PCB emissions was generally correlated with that of measured atmospheric levels, suggesting that population could be a good surrogate for the intensity of PCB emission in Korea. The simulated time trends of air concentrations well reflected those of emission with a peak in the mid-1970s and insignificant levels in the 2030s. The model predicted that the contribution of volatile PCBs had increased after emission reduction iii the 1970s. This trend would continue until the early 2030s. The measured and modeled PCB levels in the 2000s were in an agreement of an order of magnitude, and their congener patterns were very similar. Consequently, despite of high uncertainty for emission estimates, the emission data for Korea used in this study is considered to be reliable. The results of this study could be compared with simulation data based on a new emission inventory to be developed by measurements in the near future.