• 수산해양기술연구
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• 제28권4호
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• pp.385-397
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• 1992

Current measurements at 3 sections and numerical experiments were carried out in Masan Bay to understand the effect of the wind on the residual currents and pollutant transport. The vertical distribution of horizontal velocities were directly affected by the wind at the depths of 1m and 2m beneath the sea surface. Analysis of the velocity data suggested that changes in the vertical gravitational circulation contributed to the net circulation. The net transport of water through the northern part of the bay was observed to be landward, with wind-induced transport of about 100m super(3)/s. Hence, wind is concluded to be the dominant mechanism driving the net circulation in the northern area of Masan Bay. Numerical experiments are shown that when S wind with 5m/s blew, northern area of the bay was generated the horizontal circulation of clockwise and local gyre. On the contrary of those, N wind made her to the anti-clockwise. In the case of no wind, the tidal residual current(constant flow) is very small or neglected except the bay-mouth. The inflow or outflow pattern of the mouth is considered as the flows generated by tidal residual current only. The distance of wind-induced transport of pollutant was as long as 2 times of no wind during the one tidal period.

• 한국환경과학회지
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• 제12권1호
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• pp.23-34
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• 2003

Urban air quality is usually worse than that of rural counterpart. The contrasting atmospheric properties seem to be direct result of different urban-rural air pollutant emission. Hence, the emission estimation of air pollutants plays an important role to the atmospheric environmental management. The main purpose of this study is to find out the temporal and spatial distribution of air pollutant emission in Daegu area. For the study, the Daegu statistical yearbook and data of waste facilities and the report on traffic survey issued by Daegu metropolitan city and the statistical yearbook on the road capacity issued by the ministry of construction and transportation are used. Each item for the emission estimation is $SO_2$, CO, HC, $NO_x$, PM-10 from point, line and area source. The result were as follow; (1) The air pollutants with the highest amount of emission from the emission source is CO followed by $NO_x$, $SO_2$, PM-10, HC in descending order of magnitude. (2) The annually totaled air pollutant emission consists of 81%(73,185 ton/year) of line, 11%(9,589% ton/year) of area and 8%(7,445 ton/year) of point source in Daegu. Air polluant emission was mainly due to line sources. (3) High-emission of the air pollutants of line source appeared ariond Bukgu, Dalseonggun, Dongu and Seogu ; the areas with highway networks.

• 한국해양환경ㆍ에너지학회지
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• 제5권3호
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• pp.23-27
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• 2002

기름유출이나 적조 등에 의한 해양오염사고가 빈번하게 발생되고 있고, 이들을 처리하기 위한 방제작업이 수행되고 있다. 효과적인 방제작업을 수행하기 위해서는 오염원의 거동을 방제자가 신속히 예측하여 오염원의 확산을 막아야한다. 본 연구는 해양오염원의 이동예측을 방제자가 손쉽게 수행 할 수 있는 프로그램 개발에 관한 내용이다. 본 논문에서는 GUI 기법을 이용하여 연구중인 ODM(Oil Diffusion Modelling)의 구성과 내용에 관하여 소개하였다. ODM은 전ㆍ후 처리부분과 수치해석 부분으로 나뉘어 있으며 윈도우 환경으로 구성되어 방제담당자가 손쉽게 프로그램을 작동시켜 결과를 확인 할 수 있도록 하였다. 본 연구가 계속 진행됨으로서 보다 편리한 확산예측 프로그램이 개발될 것으로 기대한다.

• 한국환경보건학회지
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• 제50권3호
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• pp.191-200
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• 2024

Background: Busan is a rapidly industrializing city with many mixed residential and industrial areas. Fine dust emissions from mobile pollution sources such as ships and vehicles are particularly high in Busan. Objectives: This study analyzed the spatial distribution of air pollutants over the past three years and identified the impact of air pollutants through mobile source data in Busan. Methods: We obtained air pollutant data on fine particulate matter (PM₁₀), ultrafine particulate matter (PM_2.5), nitrogen dioxide (NO₂), sulfurous acid gas (SO₂), and ozone (O₃) for the last three years (source: airkorea.or.kr) and analyzed the spatial distribution using SAS 9.4 and Surfer 23. For the mobile pollutant data, we used CCTV data from major intersections in Busan to identify truck and car traffic, and visualized traffic density with QGIS. Results: The analysis of the concentration of air pollutants over three years (2020~2022) showed that all were lower than the annual environmental standards with the exception of PM_2.5. PM₁₀ and PM_2.5 were found to be highly concentrated in the western part of the area, while NO₂ was high in the port area of Busan and SO₂ was high in the western part of the area and near the new port of Busan. In the case of O₃, it was high in the eastern part of the city. The traffic volume of freight vehicles by intersection was concentrated in the West Busan area, and the traffic volume for all cars was also confirmed to be concentrated at "Mandeok Intersection" located in the West Busan area. Conclusions: This study was conducted to determine the relationship between air pollutants emitted from motor vehicles and the distribution of air pollutants in Busan. The spatial distribution of PM₁₀ and PM_2.5 correlates with traffic volume, while high concentrations of SO₂ and NO₂ near the port are associated with ship emissions.

• 한국환경과학회지
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• 제23권12호
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• pp.2089-2099
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• 2014

Emissions from aircraft have impacts on the air pollution of airport and the surrounding area. There are methods of emissions calculated as Tier 1, Tier2, Tier 3A and Tier 3B. Thus, this study investigated emissions from aircraft at the Gimhae International Airport using EDMS(Emissions & Dispersion Modeling System) program. Results of estimation from aviation emissions, Tier 3B considering all parts which can occur at the airport has the largest amount emissions. In order to understand the relation between aviation emissions and distribution of ozone concentration over airport area, numerical evaluation were carried out. Although the difference of surface ozone distribution between numerical assessment with and without aviation emissions was little, effects of air pollution at airport area from aviation emissions of NOx and VOCs.

• 환경영향평가
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• 제14권5호
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• pp.255-262
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• 2005

In summer and early autumn, eutrophication occurs occasionally in many reservoirs. Lakeside macrophyte which is one of internal pollutants effects on water quality when it is submerged during water surface is rising after rainy season. This study include examination of pollutant load, species of plant, community structure and productivity of macrophyte in unit area at lakeside. The result of this research will be used as a guideline of water quality management on reservoir through assessing water quality effect of submerged plant. The areal distribution, composition of species and submerged area of macrophyte changes according to rainfall pattern every year, so it is difficult to calculate nutrient load annually from submerged macrophyte. In this study, the nutrient load from submerged macrophyte assess from Daecheong and Juam reservoir in 2001. TN and TP load of submerged macrophyte shows 0.043% and 0.069%, respectively, of annual discharge load on Daecheong watershed. At lake Juam, TN and TP shows 0.64% and 1.28% load, respectively. The reason that nutrient load of lake Juam is greater than that of lake Daecheong is that macrophyte distribution area of lake Juam is 5 times greater than that of lake Daecheong. Total nutrient load of lake Daecheong is 3 times greater than that of lake Juam.

• 한국농공학회지
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• 제35권4호
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• pp.47-54
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• 1993

A series of laboratory tests was performed with soil-columns which were compacted with sands and different amount of silt collected from the mid-stream of Gumgang, Korea. A known degree of concentration of PCP(Pentachlorophenol) was poured into the soil-columns and concentration of PCP was monitored and analyzed with time and depth. The results of the study are summarized as follows : 1. PCP was transported into soil along with the movement of moisture under gravitational force. The amount of PCP transported through soil or absorbed by soil varied with soil types. 2. The great amount of PCP was remained at 4~8cm section for the specimen No.2 and at 0~4cm section for the specimen Nos. 3 and 4. Based upon this result it is said that the amount of silt between 30 and 40% may be a threshold value for PCP transported through soil. 3. The amount of PCP remained in the specimen Nos. 2, 3 and 4 is greater than that in the specimen No.1 due to high specific surface of silt and high attraction force between PCP and silt particles in the specimen Nos. 2, 3 and 4. 4. It is said that groundwater under highly permeable soil layer such as specimen No.1 is easily polluted by PCP. That is because the PCP is basically migrated with water under the gravitational force.

• 한국대기환경학회지
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• 제9권4호
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• pp.303-309
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• 1993

An observational study of urban heat island was carried out using field data obatined during 6 days in May and August 1992 in Chunchon(population size 180.000). Air temperature was measured at 64 points along two sampling ruoutes by themisters attached to cars. Both routes cover urban and rural area and across the cneter of urban area. Continuous observation of air sonde was perfomed to clarify heights of nocturnal boundary layer(NBL) at the center of urban area. Surface meteorological observations were performed at both urban and rural sites. This study showed that heat island phenomena was obviously observed at the urbanized area during the night time with low wind speed. The average NBL heights exteded to about 10 meters, but varied with meteorological conditions. After sunset, the air temperature decreased with time at both sites and cooling rate at the urban site was greater than the rural site. The maximum heat island intensity was 7.5$^{\circ}$C at 21 LST, May 4. Usingthe two meteorological data sets obtained from urban and rural sites, the air pollutant concentration was calculated by Gaussian plume model which can obtain not only horizontal distribution of concentration but also vertical distribution. The result indicated that the concentration resulted from urban meteorological data set was lower than that from rural meteorological data set. It was also calculated that the air pollutant extended to higher level in urban meteorological data set than that in rural meteorological data set.

• 한국측량학회지
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• 제17권3호
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• pp.273-282
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• 1999

대기환경분야에 GSIS를 활용하기 위해서는 우선적으로 이러한 연속면적 성질을 지닌 대기오염이나 기후인 자를 비롯한 연속면(continuous surface)의 특성을 가진 환경인자의 공간분포를 도면화 할 수 있어야 한다. 이를 위해서는 몇몇의 한정된 지점에서 측정된 점관측(point observation)자료에 의존하여 전 지역의 분포를 추정해야 한다. 본 연구에서는 자동차에 의한 대기오염물질 발생현황을 실질적으로 파악하기 위한 조사ㆍ연구의 일환으로 서울시 전지역을 대상으로 실시한 서울시 교통센서스의 자동차 통행량 자료, 오염물질별 배출계수 및 GIS-T용 수치지도등의 자료들을 이용하여 오염물질 배출특성을 지역별, 항목별, 시간별로 가시화 할 수 있는 GSIS기법의 적용성을 검토하고자 하였다.

• Nuclear Engineering and Technology
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• 제53권1호
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• pp.244-252
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• 2021

Wind plays an important role in cases of unexpected radioactive pollutant dispersion, deciding distribution and concentration of the leaked substance. The accurate prediction of wind has been challenging in numerical weather prediction models, especially near the surface because of the complex interaction between turbulent flow and topographic effect. In this study, we investigated the characteristics of atmospheric dispersion of radioactive material (i.e. ¹³⁷Cs) according to the simulated boundary layer around the HANARO research nuclear reactor in Korea using the Weather Research and Forecasting (WRF)-Mesoscale Model Interface (MMIF)-California Puff (CALPUFF) model system. We examined the impacts of orographic drag on wind field, stability calculation methods, and planetary boundary layer parameterizations on the dispersion of radioactive material under a radioactive leaking scenario. We found that inclusion of the orographic drag effect in the WRF model improved the wind prediction most significantly over the complex terrain area, leading the model system to estimate the radioactive concentration near the reactor more conservatively. We also emphasized the importance of the stability calculation method and employing the skillful boundary layer parameterization to ensure more accurate low atmospheric conditions, in order to simulate more feasible spatial distribution of the radioactive dispersion in leaking scenarios.