• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.572-576
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• 2002

Volatile Organic Compounds(VOCs) contribute to the formation of ozone and PAN which are injurious to health through complex photochemical reactions. Growing consumption of fossil fuels results in significant emission of VOCs and other air pollutants into the atmosphere. In this study, Ambient an grab samples of VOCs were collected at the platform and the concourse of six stations in the subway from February 21th to 28th. Among the total contents, Toluene (118.74 ppm) showed the highest concentration in the Indukwon station platform while other contents were measured low concentrations. Also, the platform concentrations were higher than the concourse concentrations through the whole contents.

• 한국대기환경학회지
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• 제16권4호
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• pp.309-316
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• 2000

Chemical compositions of air pollutants with fine particles (<2.5 ${\mu}{\textrm}{m}$, PB2.5) were evaluated at background site. Kangwha. in Korea during the winter season. The data set was obtained for seventeed days with 24-hour sampling from December 11 to 16, 1996 and from January 9 to 1997. The chemical species have been measured {{{{ {SO }`_{4 } ^{2- } }}}}, {{{{ { NO}`_{3 } ^{- } }}}}, {{{{ { NH}`_{4 } ^{+ } }}}}. OC and EC in the particulate phase, NH3 HNO3, HCl and SO2 in the gas phase using the three stage filter pack method. Mean concentration ($\mu\textrm{g}$/m3) of this study were : 35.42 for PM2.5 8.78 for organic carbon (OC) 7.25 for nss {{{{ {SO }`_{4 } ^{2- } }}}}, 4.94 for {{{{ { NO}`_{3 } ^{- } }}}}, 3.58 for {{{{ { NH}`_{4 } ^{+ } }}}} and 1.48 for elemental carbon (EC) respectively. Contributive rates of major particulate components in PM2.5 were OC (25%) nss- {{{{ {SO }`_{4 } ^{2- } }}}}(20%) ,{{{{ { NO}`_{3 } ^{- } }}}}(14%) {{{{ { NH}`_{4 } ^{+ } }}}}(10%) and EC (4%) respectively and these components could be accounted for 73% of PM2.5 mass. Reactive forms of {{{{ { NH}`_{4 } ^{+ } }}}} were considered as NH4HO3 and NH4{{{{ {SO }`_{4 } ^{2- } }}}} during the sampling periods. {{{{ { NO}`_{3 } ^{- } }}}}/({{{{ { NO}`_{3 } ^{- } }}}} + HNO3) and {{{{ {SO }`_{4 } ^{2- } }}}}/({{{{ {SO }`_{4 } ^{2- } }}}} + SO2) were calculated 0.8 and 0.9 respectively. Most of these compounds might be formed in partiiculate phase in the air. Correlation coefficient between OC and EC was 0.866 which might have the same sources during the sampling periods,.

• 한국환경과학회지
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• 제26권9호
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• pp.1045-1055
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• 2017

Characterization of spatio-temporal variations in $PM_{2.5}$ in Gyeongnam (GN) province during 2015-2016 was investigated to assess the air quality in this area in terms of fine particles. Yearly mean concentrations of $PM_{2.5}$ ranged from 19.1 to $29.5{\mu}gm^{-3}$. High concentrations of $PM_{2.5}$ were observed in spring ($21.2-30.3{\mu}gm^{-3}$) and winter ($20.2-30.3{\mu}gm^{-3}$). Low concentrations of $PM_{2.5}$ were generally observed in fall ($16.2-23.2{\mu}gm^{-3}$). $PM_{2.5}$ concentration was highest in the morning (10 AM). The fractions of $PM_{2.5}$ in $PM_{10}$ were 0.51-0.62 and two were significantly correlated (r=0.779-0.830), suggesting common sources (fossil fuel combustion, mobile sources, etc). CO was significantly correlated with $PM_{2.5}$ in highly urbanized areas such as the city of Changwon (CW, r=0.711), compared to other air pollutants ($SO_2$, $NO_2$, and $O_3$), suggesting dominance of industrial combustion sources.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.81-86
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• 2005

The purpose of this study is to develop venturi type after-burner in order to obtain pollutant reduction effect and find the best stable combustion condition. For this purpose, through a flow analysis, the shape of venturi type was made and flame holder locations were also decided by measuring chemical species at before and after the after-burner. Also, various chemical species concentration were measured at changing the induced air rates and the oxygen for oxygen enrichment for the solution the problems of much oxygen flow rate and the flame stability range. As results of this study, a flow distribution and the purification effect was excellent at venturi contraction 0.5 and flame holder location 12mm below the center of Venturi throat. On the purification characteristics, we found that pollutants reduction was effective when area ratio and oxygen are increased. But there are suitable quantities due to the flame shape change and combustion efficiency.

• 한국환경보건학회지
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• 제34권3호
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• pp.219-225
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• 2008

Many building materials may contain high concentrations of volatile organic compounds (VOCs) and other hazardous pollutants(HAPs). Specifically, VOCs discharged by indoor building material may cause "new house" syndrome, atopic dermatitis etc. The diffusion coefficient and initially contained total VOC quantity were determined using microbalance experiments and small chamber tests. Interactions between volatile organic compounds (VOCs) and vinyl flooring (VF), a relatively homogenous, diffusion-controlled building material, were characterized. Rapid determination of the material/air partition coefficient (K) and the material-phase diffusion coefficient (D) for each VOC was achieved by placing thin VF slabs in a dynamic microbalance and subjecting them to controlled sorption/desorption cycles. K and D are shown to be independent of concentration for all of the VOCs and water vapor. This approach can be applied to other diffusion-controlled materials and should facilitate the prediction of their source/sink behavior using physically-based models.

• 한국분무공학회지
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• 제1권2호
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• pp.16-23
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• 1996

In case of a high-speed D.I. diesel engine. the injected fuel spray is unavoidable that the impinging on the wall of piston cavity and in this case the geometry of piston cavity has a great influence on the atomization structure and air flow fields. In the field of combustion and in many other spray applications, there are clear evidence of correlation between spray structure and emission of pollutants. Ordinary, the combustion chamber of driving engine have unsteady turbulent flow be attendant on such as the change of temperature, velocity and pressure. So the analysis of spray behavior is difficult. In this study, a single spray was impinged on each cavity wall at indicated angle in a quiescent atmosphere at room temperature and pressure, as being the simplest case, and 3 types of piston cavity such as Dish, Toroidal and Re-entrant type was tested for analyzing the influence of cavity geometry. And hot wire probe was used for analyze non-steady flow characteristics of impinging spray, and to investigate the behavior of spray, the aspects of concentration c(t), standard deviation $\sigma(t)$ and variation factor (v.f.) was measured with the lapse of time.

• 한국대기환경학회지
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• 제15권6호
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• pp.713-725
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• 1999

Air pollutants($SO_2$, NOx, $O_3$ and aerosol number) were measured using an aircraft to investigate the characteristical features of long-range transport of sulfur compounds over the Yellow Sea for the periods of 26~27 April and 7~10 November in 1998. The mean $SO_2$ concentrations of April 26th~27th and November 7th~10th flight were 0.6~1.8 ppb and 0.5~8.3 ppb, respectively, and the sulfur transport was largely limited to the atmospheric boundary layer. Especially, $SO_2$ increased up to 8.3 ppb altogether with the increase of particle number concentraton especially on November 8, 1998. In addition, $O_3$ was remarkably decreased against the increase of $SO_2$and particle number concentrations. This enhanced $SO_2$ concentration occurred in the low level westerlies in association with the anticyclonic flow over Southern China and the cyclonic circulation over Manchuria. Aerosol analyses at Taean site also showed that sulfate concentration increased 2~3 times higher than those of another sampling days, which could suggest possible interactions between aerosol particels and tropospheric ozone. A rigorous evaluation will be possible after the more intensive measurements and quantitative analyses with detailed chemistry model including the postulated heterogeneous mechanism.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.74-75
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• 2021

In the recent 2017 annual average fine dust concentration (PM2.5) statistics released by the Organization for Economic Cooperation and Development (OECD), Korea has a high concentration of 25.14㎍/m3, which is about twice the average of 12.5㎍/m3 in OECD countries. Fine dust (PM2.5) is the main source of secondary pollutant production by the reaction of primary pollutants emitted from automobiles and thermal power plants, mainly composed of sulfates, nitrates, and organic carbon. The permeable block is an eco-friendly product that prevents rainwater from collecting on the surface of the road because it does not penetrate the groundwater properly, and is widely constructed on sidewalks or parking lots to recharge groundwater in case of rain. In addition, the pavement of the permeable block is a fundamental solution to reduce pollution by preventing rainwater from flowing into the stream, and it also has the advantage of easy replacement as well as low replacement costs. Therefore, this study was a basic experiment to produce permeable blocks mixed with TiO2 and diatomite to improve indoor air quality, and intended to analyze the flexural strength and compressive strength of permeable blocks mixed with TiO2.

• Journal of Preventive Medicine and Public Health
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• 제34권3호
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• pp.253-261
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• 2001

Objectives : To evaluate the hypothesis that air pollution could increase emergency room visits for respiratory diseases, and if so, to quantify the strength of association between those. Methods : We compiled daily records of hospital emergency room visits for respiratory diseases in Seoul, from November 1. 1955 to October 31. 1996, by using medical utilization data of unscheduled visits. In addition, air quality and weather data for the same period was collected. And a case-crossover design was applied by adopting conditional logistic regression analysis to determine the relationship between air pollutants and emergency room visits for respiratory diseases. In particular, the control periods were chosen by a bidirectional paired matching technique 7, 14, and 21 days before and after the case periods. Results : Only ozone was associated with the increased number of emergency room visits for respiratory diseases. The relative risk according to a 30ppb increase of ozone concentration (24hr mean, lagged 1day) was 1.91(95% confidence interval = 1.78-2.05). Conclusion : There was a statistically significant association between the ambient ozone and daily emergency room visits for respiratory diseases.

• 토지주택연구
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• 제6권4호
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• pp.231-237
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• 2015

본 연구는 다변화 되는 건설환경에서 모듈러 주택에 대한 관심이 높아지고 있어 모듈러 목업 주택을 대상으로 신축시 실내공기질 현황을 측정하였다. 붙박이 가구가 미설치된 세대(101호)와 붙박이 가구가 설치된 세대(102호), 2세대를 대상으로 시간경과에 따라 3차 측정을 실시하였다. 1차는 마감 및 붙박이 가구 설치 직후 측정하였으며 2차는 베이크아웃 실시 이후, 3차는 약 2.5개월(77일) 이후 측정하였다. 측정결과 1차 측정시 붙박이 가구 설치세대가 오염물질 방출농도가 높았으나 톨루엔의 경우를 제외하고 모두 권고기준 이하로 나타났다. 3차 측정시에는 톨루엔과 스티렌을 제외하고 두세대가 유사한 방출량으로 나타났으며 두세대 모두 미미한 수준으로 방출량이 낮아졌다. 이는 측정세대 모듈이 적어($14.7m^2$) 베이크아웃 및 환기에 의한 영향이 크게 나타난 것으로 판단되며 이를 통해 오염물질이 외부로 방출되어 저감된 것으로 판단된다. 일반 공동주택의 입주시점을 고려한다면 모듈러 주택의 경우도 모두 실내공기질 권고기준 이하로 나타날 것으로 판단되며, 가구에 의한 영향은 톨루엔이 가장 큰 영향을 받는 것으로 나타났다. 향후에는 모듈조합을 통해 중형 이상 규모 모듈러 주택에 있어서 가구설치 여부에 따른 상관관계를 살펴 볼 필요성이 있을 것으로 판단된다.