• 한국대기환경학회지
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• 제21권3호
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• pp.357-365
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• 2005

The typical patterns of surface $O_3$ pollution and their dependence on meteorology were studied in the Greater Seoul Area (GSA) during warm season (April-September) from 1998 to 2002. In order to classify the $O_3$ pollution patterns, two-stage (average linkage then k-means) clustering technique was employed based on daily maximum $O_3$ concentrations obtained from 53 monitoring sites during high $O_3$ events (118 days). The clustering technique identified four statistically distinct $O_3$ pollution patterns representing the different horizontal distributions and levels of $O_3$ in GSA. The prevailed pattern (93 days, $49.5\%$) distinctly showed the gradient of $49.5\%$ concentrations going from west to east in GSA. Very high $49.5\%$ concentrations throughout GSA (24 days, $12.8\%$) were also found as a significant pattern of severe $O_3$ pollution. In order to understand the characteristics of $O_3$ pollution patterns, the relationship between $O_3$ pollution patterns and meteorological conditions were analyzed using both synoptic charts and surface/upper air data. Each pattern was closely associated with surface wind interacted with synoptic background flow allowing to transport and accumulate $O_3$ and its precursor. In particular, the timing and inland penetration of sea-breeze were apparently found to play very important role in determining $O_3$ distributions.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권3호
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• pp.215-220
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• 1999

$SO_2$and CO gas removal characteristics of a wire-to-cylinder type nonthermal discharge plasma reactor in various applied voltage (-dc, ac, fast rising pulse and high frequency pulse) and a crossed dc magnetic field have been investigated. The experiment has been emphasized on the oxidizing characteristics of $SO_2$ and CO gas by $O_3$ and the applying of a crossed magnetic field, which would induce the cyclotronic and drift motions of electrons making the residual time longer in the removal airgap space. And it also would enhance the energy of electrons and the electrophysicochemical actions to remove the pollutant gases effectively. It is found thatthe corona onset voltage and the breakdown voltage were decreased with increasing the crossed magnetic field and decrease initial fed $SO_2$and CO concentration. As a result, a higher ozone generation and $SO_2$ and CO gas removal rate of 20[%] can be obtained with -dc, ac and fast rising pulse corona discharges in the crossed dc current-induced magnetic field. But high frequency pulse didn't show effect in applying of a crossed magnetic field.

• 태양에너지
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• 제16권2호
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• pp.49-63
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• 1996

측정지의 고도는 일사량 측정에 영향을 주는 중요한 요소이다. 대기중에 내포되어 있는 영속성개스 즉, 오존과 수증기 등은 대기의 순수한 혼합물 성분은 그 농도가 고도와 밀접한 함수관계를 갖기 때문에 해당 측정지 고도는 그 지역의 대기를 구성 하고 있는 성분에 상대적으로 비례하여 일사에 영향을 준다. 이에따라 소백산과 그인접 저지대인 풍기를 대상으로 일사강도를 측정하여 지역별 일사량자원의 특성과 향후 에너지자원으로서의 가능성을 목표로 두고 고지대와 저지대사이의 상호 비교가 가능하도록 하였다. 현지 측정사업의 내용을 중심으로 지금까지 나타난 결과를 살펴보면, 1) 소백산의 연평균 수평면 전일사량 조건은 청명한 날을 기준으로 하루에 4,093 $kcal/m^2$로 나타났다. 2) 소백산에서의 일사강도는 인접 저지대인 풍기보다 $6{\sim}7%$ 정도 높게 나타났다. 3) 대기청명도는 동일한 위도상인 소백산과 풍기지역간의 격차가 현저하게 존재 하였다. 는 점으로 요약된다.

• 한국초등과학교육학회지:초등과학교육
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• 제28권2호
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• pp.142-153
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• 2009

The purpose of this study was to survey primary students' perception of the global and local environmental issues. The subjects were 853 fifth primary students in Seoul, Busan, Daejeon, Anyang, Gimpo and Cheongju. The results were as follows: First, the perception level of the global environmental issues were global warming (M=3.99), drinking-water pollution (M=3.92), acid rain (M=3.77), yellow dust (M=3.66), ozone depletion (M=3.57), deforestation in tropical areas (M=3.52), desertification (M=3.36), biodiversity (M=3.40) and their perception level of local environmental issues were waste disposal (M=3.87), air pollution (M=3.74), bad smell (M=3.70), noise (M=3.61), river pollution (M=3.57), soil pollution (M=3.44). Second, it was shown that the metropolitan students' perception levels of environmental issues were higher than the non-metropolitan students'. There wasn't a significant difference in the perception levels of two scale environmental issues and characteristics for sex (p>.05). Third, the result of analyzing on the effects between characteristics was that the factors like 'environmental interest' and 'impact on personal life' had a strong influence on the 'behavior will' to solve the global environmental issues, and 'environmental interest' and 'personal knowledge' had a strong influence on the 'behavior will' to solve the local environmental issues. Fourth, the result of analyzing on the characteristics according to the types of the environmental issues showed that 'personal knowledge', 'environmental interest' and 'behavior will' were high in the global environmental issues (p<.01) and 'virtual contamination', 'human responsibility' and 'impact on personal life' were high in the local environmental issues (p<.05).

• 한국대기환경학회지
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• 제32권5호
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• pp.536-546
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• 2016

The diurnal variations of $O_3$ and $NO_2$ in an urban park and the effects of air temperature and wind speed on the diurnal variations are investigated. $O_3$ and $NO_2$ concentrations were observed at a site in an urban park of Seoul from 27 July 2015 to 9 August 2015. The $O_3$ and $NO_2$ concentrations observed in the urban park are compared to those observed at the Gangnam air quality monitoring station (AQMS). The $O_3$ concentration is higher in the urban park than at the Gangnam AQMS in the daytime because the amount of $O_3$ dissociated by NO is smaller as well as partly because the amount of $O_3$ produced in the oxidation process of biogenic volatile organic compounds (VOCs) is larger in the urban park than at the Gangnam AQMS. The $NO_2$ concentration is lower in the urban park than at the Gangnam AQMS during day and night because the observation site in the urban park is relatively far from roads where $NO_x$ is freshly emitted from vehicles. The difference in $NO_2$ concentration is larger in the daytime than in the nighttime. To examine the effects of air temperature and wind speed on the diurnal variations of $O_3$ and $NO_2$, the observed $O_3$ and $NO_2$ concentrations are classified into high or low air temperature and high or low wind speed days. The high $O_3$ and $NO_2$ concentrations in the daytime appear for the high air temperature and low wind speed days. This is because the daytime photochemical processes are favorable when the air temperature is high and the wind speed is low. The scatter plots of the daytime maximum $O_3$ and minimum $NO_2$ concentrations versus the daytime averages of air temperature and wind speed show that the daytime maximum $O_3$ and minimum $NO_2$ concentrations tend to increase as the air temperature increases or the wind speed decreases. The daytime maximum $O_3$ concentration is more sensitive to the changes in air temperature and wind speed in the urban park than at the Gangnam AQMS.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.915-922
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• 2017

내열 및 내유성 고무복합체 특성연구(The study on the thermal and oil resistance rubber composite), 2016.[6] 연구에서는 고온($150^{\circ}C$, $175^{\circ}C$, $200^{\circ}C$) 조건의 고온촉진노화를 통하여 불소고무 복합체의 수명을 예측하였다. 일반적인 고무제품은 온도, 습도, 오존, 빛, 유제, 기계 및 전기적 응력 등의 특성저하 인자에 따라 다른 특성을 나타낼 가능성이 있으며, 이러한 문제를 해결하기 위하여 "내열 및 내유성 고무복합체 특성연구"[6] 연구에서 얻어진 고온촉진노화에 의한 수명 예측값과 저온촉진노화간의 인장강도 변화율 및 신장률 변화율 그리고 부피 변화율, 무게 변화율, 두께 변화율 및 열전도도를 비교 검토하였다. 검토 결과, 요구 한계수명은 모두 만족하였지만 고온촉진노화 결과와 저온촉진노화 결과 간 변화율에서 약간의 격차를 보였다. 이러한 변화율 격차가 일어나는 원인은 고온촉진노화에서는 노화 시 불소고무의 주사슬 분해로 인하여 인장강도, 신장률 감소 및 부피, 무게, 두께 증가가 일어나는데 비해 저온촉진노화에서는 $80^{\circ}C$에서 불소고무의 지속적 경화반응으로 인하여 인장강도, 신장률 및 부피, 무게, 두께 변화가 적게 나타났을 것으로 판단된다.

• 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.

• 한국대기환경학회지
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• 제25권6호
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• pp.550-561
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• 2009

This study is to investigate the air pollution characteristics of an industrialized midsize west-coastal city by comparing air quality to a neighboring inland city. The hourly averaged data of $O_3$, $SO_2$, $NO_2$, CO, and $PM_{10}$ measured from continuous air quality monitoring sites in Gunsan (coastal) and Jeonju (inland) were analyzed. The data set covers the period from 2004 to 2006. The annual average concentrations of the air pollutants in two cities were compared in their abundances and temporal trends as well. $O_3$ and $SO_2$ in Gunsan were relatively higher than those in Jeonju, while vice versa in case of $NO_2$ and $PM_{10}$. It seems that heavy automobile emissions from Jeonju mainly bring on higher $NO_2$ and $PM_{10}$ than those in Gunsan on annual base. $NO_2$ concentrations in both cities showed bimodal diurnal variations with peaks in the morning and in the late evening. These peaks correspond to the coupled effects of rush hour traffic and meteorological conditions (i.e., variation of mixing height and dispersion conditions). Maximum hourly averages of $NO_2$ ranged from 18 ppb to 28 ppb at Jeonju, and from 12 ppb to 20 ppb at Gunsan. $O_3$ showed typical diurnal variation with a maximum in the afternoon between 14:00 and 16:00 LST. Diurnal variations of CO and $PM_{10}$ were similar to $NO_2$ while $SO_2$ was similar to $O_3$. Seasonal variations of $PM_{10}$ in both cities indicated that their concentrations during spring season were significantly high. Asian dust storms occur frequently during spring and seem to affect increase in $PM_{10}$. High $O_3$ and $PM_{10}$ days were selected from both cities. The analyses based on the HYSPLIT trajectory model during the high $O_3$ and $PM_{10}$ showed these episodes (six cases) were mostly coincident with Asian dust storm originated from northern China and Mongolia. However, these high air pollution episodes in the west coastal cities may not only be caused by the Asian dust but also affected by other air pollutants transported from China accompanying the Asian dust.

• 항공우주기술
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• 제13권2호
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• pp.80-86
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• 2014

본 연구에서는 다목적실용위성 3호 영상을 이용하여 지표면 상의 정규식생지수 비교 분석 하고자 한다. 산출된 다목적실용위성 3호의 정규식생지수 비교 분석을 위해 동일 지점 최소 관측 시간 오차를 가지는 고해상도 GeoEye 영상이 사용되었다. 먼저, 각 밴드별 분광 정도 산출을 위해 대기 보정이 수행되었다. 대기 보정 수행을 위한 기하 정보는 다목적실용위성 3호 보조자료에 포함된 태양천정각, 태양방위각, 위성천정각, 위성방위각, 날짜 정보이다. 그리고 대기 요소에 의한 감쇄, 산란, 흡수 정보를 물리적으로 계산하기 위해 수증기량, 오존량, 에어러솔 정보가 적용되었다. 일반적으로 정확한 대기정보를 얻기 위해서는 현장관측자료가 중요하지만, 본 연구에서는 MODIS atmospheric products를 사용하였고, 대기보정 모델에서 산출된 지면 반사도는 식생지수 산출에 사용되었다.

• Korean Chemical Engineering Research
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• 제52권6호
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• pp.755-767
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• 2014

염소(Chlorine)는 지구상에서 가장 많이 생산되고 사용되는 화학물질 중 하나로, 비가연성 물질이지만 독성, 오존층 파괴 및 활발한 반응성을 지닌 물질이며, 현대사회는 염소와 그 유도체의 사용 없이 윤택한 삶을 유지하는 것이 거의 불가능할 정도로 의약품과 세정제, 방취제, 살균제, 제초제, 살충제 및 플라스틱을 비롯하여 공산품의 40% 이상에 사용되고 있는 지구상의 대표적인 화학물질이다. 국내의 경우, 염소는 전국의 다양한 사업장(중소기업, 정수장, 운송회사 등)에서 취급 및 유통되고 있지만 관련 운송위험과 유해성 평가 연구가 부족하여, 국내외 염소누출 관련 사고에 대해 분석 및 염소 취급 및 유통에 대한 유해성 평가를 시도하였다. 특히 화학물질 운송위험지수를 국내 실정에 맞도록 모델화하였고, 액화 염소를 포함한 13종 화학물질의 운송위험성 모사를 통해 유해성 평가를 실시하였다. 이는 염소를 비롯한 다양한 화학물질에 대한 화학물질 운송위험지수 모델을 적용하여 정형화된 유통 유해성평가를 할 수 있을 것으로 판단된다.