• Journal of Preventive Medicine and Public Health
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• 제32권2호
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• pp.191-199
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• 1999

대기오염이 인체에 미치는 영향을 정량적으로 분석하기 위하여 1991년부터 1995년까지의 서울시 사망자료와 대기오염 자료를 general additive Poisson model 을 사용하여 분석하였다. 우리 나라에서도 외국의 연구 결과와 마찬가지로 대기 오염 물질의 증가가 사망자 수의 증가에 유의하게 영향을 미치는 것으로 평가되었다. 특히 본 연구에서 나타난 특성은 일반적으로 많이 알려진 분진에 의한 영향 보다는 오존에 의한 영향이 두드러진다는 것이다. 오존은 100ppb가 증가할 때 마다 사망자 수를 3-10% 증가시키는 것으로 평가되었다. 즉 오존주의보가 발령될 때마다 서울시에서는 많게는 평소보다 10%정도의 추가적인 사망이 발생하는 것으로 추정된다. 이러한 연구결과는 우리 나라의 대기오염 양상이 분진과 $SO_2$ 중심의 '런던스모그'형에서 오존과 $NO_2$ 등에 의한 광화학적 스모그로 바뀌고 있는 사실을 감안할 때 시사하는 바가 매우 크다고 할 수 있다. 따라서 앞으로는 병원입원율, 또는 응급실 내원환자수에 대한 오존의 영향을 평가할 수 있는 연구들이 이어져야 할 것으로 생각되며, 더불어 오존 오염을 감소시킬 수 있는 구체적인 정책들이 시급히 시행되어야 할 것으로 생각된다.

• 한국환경과학회지
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• 제13권7호
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• pp.645-653
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• 2004

Indoor air quality is affected by source strength of pollutants, ventilation rate, decay rate, outdoor level, and so on. Although technologies measuring these factors exist directly, direct measurements of all factors are not always practical in most field studies. The purpose of this study was to develop an alternative method to estimate these factors by application of multiple measurements. For the total duration of 30 days, daily indoor and outdoor $NO_2$ concentrations were measured in 30 houses in Brisbane, Australia, and for 21 days in 40 houses in Seoul, Korea, respectively. Using a box model by mass balance and linear regression analysis, penetration factor (ventilation divided by sum of air exchange rate and deposition constant) and source strength factor (emission rate divided by sum of air exchange rate and deposition constant) were calculated, Sub-sequently, the ventilation and source strength were estimated. In Brisbane, the penetration factors were $0.59\pm0.14$ and they were unaffected by the presence of a gas range. During sampling period, geometric mean of natural ventilation was estimated to be $l.l0\pm1.5l$ ACH, assuming a residential $NO_2$ decay rate of 0.8 hr^{-1}$ in Brisbane. In Seoul, natural ventilation was $1.15\pm1.73$ ACH with residential $NO_2$ decay rate of 0.94 hr^{-1}$ Source strength of $NO_2$ in the houses with gas range $(12.7\pm9.8$ ppb/hr) were significantly higher than those in houses with an electric range $(2.8\pm2,6$ ppb/hr) in Brisbane. In Seoul, source strength in the houses with gas range were $l6.8\pm8.2$ ppb/hr. Conclusively, indoor air quality using box model by mass balance was effectively characterized.

• 대한기계학회논문집B
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• 제37권5호
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• pp.481-488
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• 2013

10 %의 암모니아가 첨가된 메탄 연료의 비예혼합 확산화염에서, 산소/이산화탄소 및 산소/질소의 산화제 내에 산소 비율의 변화에 따른 질소산화물($NO_x$)의 생성 특성을 실험 및 수치해석적으로 조사하였다. 동축류 제트 화염의 실험에서, 산소/이산화탄소의 산화제인 경우, 측정된 $NO_x$은 산소 비율의 증가에 따라 약간 증가하는 경향을 보였다. 반면에, 산소/질소의 산화제인 경우, $NO_x$은 0.7의 산소 비율에서 최대로 측정되었으며, 산소 비율에 따라 비단조적인 경향을 보였다. 결과적으로, 암모니아가 첨가된 메탄 화염에서 배출되는 $NO_x$는 일반 공기의 조건보다 순산소 연소 조건의 경우가 더 크게 측정되었다. 한편, 다양한 산화제의 조건에 대하여 $NO_x$ 생성 특성을 분석하기 위해서, 동일한 화학반응 메커니즘을 적용하여 1 차원 및 2 차원의 수치해석을 수행하였다. 그 결과, 산소/질소의 산화제에서 2 차원의 수치해석 결과가 실험적으로 측정된 $NO_x$의 배출 특성을 비교적 잘 예측하였다.

• 한국환경보건학회지
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• 제35권1호
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• pp.11-20
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• 2009

This study was conducted in industrial area. The level of nitrogen dioxide was measured indoor, outdoor, work and personal in an study area within 5 km from source of pollution and control area 15 km farther from August, 2006 to September. The followings are the summary of this research. The concentration of the indoor and the outdoor $NO_2$ levels in the industrial area are 18.41$\pm$6.35 ppb, 18.51$\pm$3.26 ppb each, and the indoor/outdoor concentration rate is 0.99. The concentration of $NO_2$ in the workplace is 18.59$\pm$10.16 ppb, and the individual exposure rate is 18.80$\pm$5.71 ppb. The concentration of the indoor and the outdoor $NO_2$ levels control area are 12.57$\pm$3.82 ppb, 9.68$\pm$2.16 ppb each, and the indoor/outdoor concentration rate is 1.33. The personal exposure rate is 14.49$\pm$10.06 ppb. The residents of the each area and those of the comparative area spend 80.9% and 76.9% each their time in the indoor. It shows they spend most of their time in indoor. The predictions of the individual exposure rates in the industrial area and the comparative area are 15.10$\pm$6.14 ppb and 10.52$\pm$3.82 ppb each, The concentration levels measured by passive sampler are 18.80$\pm$5.71 ppb and 14.49$\pm$10.34 ppb each. The result of the research is the analysis of the personal exposure rate in indoor, outdoor and workplace of industrial area. This research may bo used as a basic data to manage and to establish the plan for $NO_2$ gas of the industrial area.

• Journal of Preventive Medicine and Public Health
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• 제51권3호
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• pp.130-139
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• 2018

Objectives: Air pollution is a growing concern in Korea because of transboundary air pollution from mainland China. A panel study was conducted to clarify the effects of air pollution on respiratory symptoms and health-related quality of life (HR-QoL) in outpatients with and without chronic obstructive pulmonary disease (COPD) in Korea. Methods: Patients filled out a questionnaire including self-reported HR-QoL in February and were followed up in May and July. The study was conducted from 2013 to 2015, with different participants each year. Air quality parameters were applied in a generalized estimating equation as independent variables to predict factors affecting HR-QoL. Results: Lower physical fitness scores were associated with Asian sand dust events. Daily activity scores were worse when there were high concentrations of particulate matter (PM) less than $10{\mu}m$ in diameter ($PM_{10}$). Lower social functioning scores were associated with high PM less than $2.5{\mu}m$ in diameter and nitrogen dioxide ($NO_2$) concentrations. High $NO_2$ concentrations also showed a significant association with mental health scores. Weather-related cough was prevalent when $PM_{10}$, $NO_2$, or ozone ($O_3$) concentrations were high, regardless of COPD severity. High $PM_{10}$ concentrations were associated with worsened wheezing, particularly in COPD patients. Conclusions: The results suggest that PM, $NO_2$, and $O_3$ cause respiratory symptoms leading to HR-QoL deterioration. While some adverse effects of air pollution appeared to occur regardless of COPD, others occurred more often and more intensely in COPD patients. The public sector, therefore, needs to consider tailoring air pollution countermeasures to people with different conditions to minimize adverse health effects.

• 환경위생공학
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• 제14권2호
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• pp.68-74
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• 1999

The atmospheric concentrations of Nitrogen Dioxide ($NO_2$) and Total Suspended Particulates (TSP) at the traffic road side were measured n Asan area, Choongchumg-namdo during May 1998 and January, 1999.The results of the study are as follows;1. The aversge value of airbone $NO_2$ and TSP levels were 28.5ppb and 5.9mg/me in Asan area. 2. The concentration distribution of NO2 and TSP is high for the season of winter. On a daily pattern, somewhat high value is appeared in the afternoon. 3. For the station, terminal, and Shinchang, the average value of $NO_2$ is 33.6ppb, 27.9ppb and 24.1ppb in sequence, and the ones of TSP is 6.3mg/m3, 6.0mg/m3 and 5.3mg/m3 in order.4. The high levels of $NO_2$ and TSP were positively related to traffic volume.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.374-377
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• 2005

The distribution and changes of tropospheric nitrogen dioxide ($NO_2$) are analyzed using the satellite measurements data from GOME (Global Ozone Monitoring Experiment) and SCIMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY). We produced global maps of tropospheric $NO_2$ for 4 seasons using GOME measurements from January 1997 to June 2003. The global distribution shows high values in regions with dense population and high industrialization. Tropospheric $NO_2$ shows obvious seasonal changes depending on its emission and lifetime. Based on the good agreement between two instruments in the time period of overlapping measurements (January 2003-June2003), we linked SClAMACHY data to the GOME time series. The combined time series over the past decade indicate that $NO_2$ 1evels over China are rapidly increasing while those over Europe are decreasing. We also discussed potential application of spaceborne instruments in detecting and characterizing long-distance transport of $NO_2$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.233-236
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• 1997

An investigation has been made of the various plasma chemistry reactions that occur in the corona discharge of an electrostatic precipitator operating in a typical flue gas. As the results of investigation, sulphur dioxide is removed principally by reactions with OH radicals to produce sulphuric acid, while nitrogen oxides are removed principally by reduction via the N radical to molecular nitrogen. If electrostatic precipitator\ulcorner used for flue gases are operated with positive voltages instead of negative dc voltages, there are significant reductions in the emission of the undesirable gases SO$_2$, NO, and NO$_2$. Thus, in this paper we design the bidirectional pulse generator for removal of flue gas, where the pulse width is more than 50[nsec] and the maximum output voltage is more than 100[kVl.

• Asian Pacific Journal of Cancer Prevention
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• 제17권1호
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• pp.419-424
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• 2016

Background: The aim of this systematic review was to study the relationship between exposure to nitrogen dioxide ($NO_2$) in the ambient air and breast cancer incidence. Materials and Methods: A systematic review was performed based on the MOOSE guideline for review of observational studies. We searched five online databases (PubMed, Science Direct, Google Scholar, EBSCO, and Scopus) from their conception to June 2014. A pooled estimate of the correlation between $NO_2$ exposure and breast cancer incidence was calculated using Pearson's correlation coefficient. Results: A total of 654 titles were retrieved in the initial search of the databases. Further refinement and screening of the retrieved studies produced a total of five studies from four countries. The studies included three ecological studies (aggregate level) and two individual based studies (one prospective cohort and the other one a case-control study). The ecological studies were pooled and the meta-analysis of correlation coefficient without z transformation showed a pooled estimate of r = 0.89 with 95% CI of 0.84 to 0.95. Using z transformation, the pooled r was 1.38 with 95%CI of 1.11 to 1.59. No significant heterogeneity between studies was observed. Following a sensitivity analysis and the removal of each study from pooled analysis we did not see any significant change in the pooled estimate. Conclusions: It was concluded that there is a tendency toward a weak association between exposure to $NO_2$ in ambient air and breast cancer at the individual level and a significant association at the aggregate level.

• 한국조경학회지
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• 제33권6호
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• pp.90-97
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• 2006

The effects of a green buffer zone to protect a residential area from air pollution from industrial facilities and traffic was examined by analyzing the case of a green buffer zone in the Shiwha industrial complex. The green buffer zone is 175 m wide. The intent was to assess the dispersion patterns of atmospheric air pollutants and the reduction in concentration around the green buffer zone. To measure atmospheric sulfur dioxide$(SO_2)$ and nitrogen dioxide$(NO_2)$ concentration, badge-type passive samplers were used and set up at 76 locations in order to measure the concentration of air pollutants with respect to the spatial dispersion. The weighted mean values of $SO_2\;and\;NO_2$ concentration were $3\~57 ppb\;and\;18\~62 ppb$ and the differences among the green buffer zone, the industrial area and the residential areas were $0.7\~1.1 ppb$. Mean values of atmospheric concentrations of $NO_2$ were similar in industrial and, residential areas and the green buffer zone. Results of the study show that the effect of the green buffer zone on reducing the dispersion of air pollutants was very low. This study also recommends that micro-climate, i.e., wind direction should be considered as a factor for planning and design of green buffer zones.