• Title/Summary/Keyword: 총먼지

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Constraining Dust Properties of high-z Lyα Emitters using the ALMA Archive

  • Moon, Byeongha;Yang, Yujin;Oh, Suyeon
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.73.2-73.2
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    • 2017
  • 고적색편이의 $Ly{\alpha}$ 방출은하($Ly{\alpha}$ emitter; LAE)는 UV 연속복사에 비해 강한 $Ly{\alpha}$ 방출선을 내는 천체로서 매우 젊고, 낮은 금속함량을 가진 원시은하이다. LAE의 강한 $Ly{\alpha}$ 방출선은 먼지가 매우 적기 때문에 소광이 거의 없이 은하에서 탈출하거나, 먼지의 국지적인 분포 때문에 나타나는 것으로 추정된다. 그러나 기존 전파관측 시설의 낮은 감도 때문에 LAE의 먼지성분은 잘 알려져 있지 않다. 우리는 Atacama Large Millimeter/Submillimeter Array (ALMA)에 의해 우연히 관측된 LAE을 찾아 먼지연속복사를 직접적으로 검출하는 시도를 해 보았다. COSMOS와 ECDFS 영역에서 발견된 약 954개의 LAE 중에서 총 38개가 ALMA로 관측된 영역에 우연히 위치한다는 것을 발견하였고, 이 중 18개의 LAE에 대해 ALMA 관측영상을 모두 더하는 방법(image stacking)을 이용하여, LAE에서 방출되는 먼지연속복사의 상한선을 결정하였다: S(0.50-0.67mm) < $63.2{\mu}Jy$, S(0.21-0.38mm) < $46.7{\mu}Jy$. 본 연구에서는 비록 직접적인 검출에는 실패하였으나, 주어진 LAE 샘플에 대한 ALMA archive 검색, 원자료 다운로드, 영상 만들기, 이미지 합침 과정을 자동화하는 Python 파이프라인을 완성하였다. 이 자동화된 과정을 이용하면, 앞으로 ALMA archive가 늘어남에 따라 감도가 높아진 실험을 쉽게 반복할 수 있을 것으로 기대된다.

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자동차 배기가스와 대기오염

  • Lee, Yeong-Ju
    • Defense and Technology
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    • no.7 s.281
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    • pp.66-75
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    • 2002
  • 과거 10년전만해도 산업, 난방, 발전 등이 대기오염의 주된 원인이었으나 자동차의 증가로 말미암아 최근에는 자동차의 배기가스 즉 질산화물질(NOx), 일산화탄소(CO), 탄화수소(HC), 총먼지(TSP : Total Solid Particlate), 아황산가스(SO2) 등이 대기를 오염시키는 주요 물질이 되었다. 인구의 증가, 산업의 발달, 경제수준의 향상은 자동차 증가를 촉진시키는데 촉매제 역할을 해왔으며 대도시에서의 자동차에 의한 오염물질 배출량은 앞으로도 차량의 증가와 더불어 가속화할 전망이다.

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A Topic Analysis of Fine Particle Matter by Using Newspaper Articles (신문기사를 이용한 미세먼지 이슈의 토픽 분석)

  • Yang, Ji-Yeon
    • The Journal of the Korea Contents Association
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    • v.22 no.6
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    • pp.1-14
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    • 2022
  • This study aims to identify topics in newspaper articles related to fine particle matter and to investigate the characteristics and time series trend of each topic. Related national newspaper articles during 1990 and 2021 were collected from Bigkinds. A total of 18 topics have been discovered using LDA, and 11 clusters deduced from clustering. Hot topics include related products/residence, overseas cause(China), power plant as a domestic cause, nationwide emergency reduction measures, international cooperation, political issues, current situation & countermeasure in other countries, and consumption patterns. Cold topics include the concentration standard and indoor air quality improvement. These findings would be useful in inferring the political direction and strategies. In particular, the consumer protection policy should be expanded as the related market is growing. It will also be necessary to pursue policies that will promote public safety and health, and that will enhance public consensus and international cooperation.

Contamination Characteristics of Heavy Metals in Indoor, Outdoor and Playground of Schools in the Gochang-Gun, Chonbuk Province of South Korea (전북 고창지역 학교 실내외 환경의 중금속 오염 특성)

  • Kim, Yong-Hwan;Chung, Duk-Ho;Cho, Kyu-Seong
    • Journal of the Korean earth science society
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    • v.27 no.1
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    • pp.73-82
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    • 2006
  • Dust samples were collected from 10 middle and high schools in the Gochang-Gun, Korea. Heavy metal concentrations were determined for the dry-deposited dusts from indoor and outdoor of classroom and playground of each sampling site. Concentrations of Cd, Cu, Pb and Zn in indoor's dusts were highly concentrated. Also concentrations of Cu, Ni, Pb and Zn in outdoor's dusts were highly concentrated. Concentrations of Cd, Cu and Zn in the dusts were much higher than the world average contents in soil and environmental orientation value. These levels are similar to those of the dust samples at middle schools and high schools located in Jeonju-city, Korea. Compared with concentrations of heavy metals in soils and dusts in Korea, the environment of indoor and outdoor of classroom is highly concentrated except for Cu, Zn. The concentrations of playground is less than that of residential dust and main road dust and playground in Jeonju-city. Playground dusts in 1 school exhibited the enhanced heavy metal pollution with a pollution index (Kloke, 1979) greater than 1.0, but indoor and outdoor dusts in 7 schools exhibited the enhanced heavy metal pollution with a pollution index (by Kloke) yester than 1.0.

An Investigation on the Perception of the Effects of Particulate Matter on Oral Health (미세먼지가 구강건강에 미치는 영향에 관한 인식도 조사)

  • Kim, Jue-young;Son, Hwa-kyung
    • The Journal of the Korea Contents Association
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    • v.21 no.6
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    • pp.620-628
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    • 2021
  • This study was conducted to investigate public's perception of the effects of particulate matter (PM) in oral health and to provide specific motivation to prevent oral disease by PM. A total of 134 adults were selected as final analysis subjects from some people all over the country. The data collected is analyzed using SPSS 21.0 for windows. Frequency analysis was used to identify general characteristics and hygiene habit. For identifying perception of effects of PM on oral health, crossover analysis was used. The largest number of people recognized that the level of PM had deteriorated, compared to five years ago. That perception was highest among those in 30 years of age and service professions. Those who check the concentration of PM are more concerned with oral health care when the PM is occurred in high concentration. People who perceive PM as a threat to the oral health are more concerned about oral health care when the PM is occurred in high concentration. It is concerned those who are aware of the relationship between PM and oral health specifically manage the oral health to protect the oral cavity from PM.

A Study on the Research Topics and Trends in South Korea: Focusing on Particulate Matter (토픽모델링을 이용한 국내 미세먼지 연구 분류 및 연구동향 분석)

  • Park, Hyemin;Kim, Taeyong;Kwon, Daewoong;Heo, Junyong;Lee, Juyeon;Yang, Minjune
    • Korean Journal of Remote Sensing
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    • v.38 no.5_3
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    • pp.873-885
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    • 2022
  • The particulate matter (PM) has emerged as a hot topic around the world as it has been reported that PM is related to an increase in mortality and prevalence rates. In South Korea, the importance of PM has been recognized since the late 1990s, and various studies on PM have been conducted. This study investigated the PM research topics and trends for papers (D=2,764) published in Research Information Sharing Service (RISS) using topic modeling based on Latent Dirichlet Allocation (LDA). As a result, a total of 10 topics were identified in the whole papers, and the PM research topics were classified as 'PM reduction (Topic 1)', 'Government policy and management (Topic 2)', 'Characteristics of PM (Topic 3)', 'PM model (Topic 4)', 'Environmental education (Topic 5)', 'Bio (Topic 6)', 'Traffic (Topic 7)', 'Asian dust (Topic 8)', 'Indoor PM (Topic 9)', 'Human risk (Topic 10)'. In particular, the proportion of papers on topics 'Government policy and management (Topic 2)', 'PM model (Topic 4)', 'Environmental education (Topic 5)', and 'Bio (Topic 6)' to the toal number of papers increased over time (linear slope > 0). The results of this study provide the new literature review methodology related to particulate matter and the history and insight.

Evaluation on the Removel Effect of $PM_{10} and PM_{2.5}$ by Operating the Dust Collection Train and the Washing Train (집진열차 및 살수차운영에 의한 지하철역 미세먼지 농도 저감효과 분석)

  • 김민영;김동일;조기찬;이연수;하광태
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.421-424
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    • 2003
  • 서울지하철은 총연장 286.9km에 1일 4226회의 운행회수 그리고 대중교통수단 중 총 34.1%의 최다 수송분담율을 담당하고 있다. 서울시의 도심교통문제 해결 방안으로 시민들에게 대중교통 이용을 적극적으로 권장하고 있으나, 지하철 역사의 환경문제는 답보 상태를 유지하고 있는 것이 현실이다. 지하철내의 먼지문제는 이미 심각한 사회문제로 대두된 지 오래이며 이를 개선하기 위하여 지하철공사와 도시철도공사에서는 환기시스템의 개선, 환기 및 공기정화시설의 설치 그리고 잦은 물청소실시 등을 시행하여 오고 있어 그간 상당한 효과를 이룬 것도 사실이다. (중략)

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Bigdata Analysis of Fine Dust Theme Stock Price Volatility According to PM10 Concentration Change (PM10 농도변화에 따른 미세먼지 테마주 주가변동 빅데이터 분석)

  • Kim, Mu Jeong;Lim, Gyoo Gun
    • Journal of Service Research and Studies
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    • v.10 no.1
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    • pp.55-67
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    • 2020
  • Fine dust has recently become one of the greatest concerns of Korean people and has been a target of considerable efforts by governments and local governments. In the academic world, many researches have been carried out in relation to fine dust, but the research on the economic field has been relatively few. So we wanted to know how fine dust affects the economy. Big data of PM10 concentration for fine dust and fine dust theme stock price were collected for five years from 2013 to 2017. Regression analysis was performed using the linear regression model, the generalized least squares method. As a result, the change in the fine dust concentration was found to have a effect on the related theme stocks' price. When the fine dust concentration increased compared to the previous day, the fine dust theme stocks' price also showed a tendency to increase. Also, according to the analysis of stock price change from 2013 to 2017 based on fine dust theme stocks, companies with large regression coefficients were changed every year. Among them, the regression coefficients of Monalisa were repeatedly high in 2014, 2015, 2017, Samil Pharmaceutical in 2015, 2016 and 2017, and Welcron in 2016 and 2017, and the companies were judged to be sensitive to the concentration of fine dust. The companies that responded the most in the past 5 years were Wokong, Welcron, Dongsung Pharmaceutical, Samil Pharmaceutical, and Monalisa. If PM2.5 measurement data are accumulated enough, it would be meaningful to compare and analyze PM2.5 concentration with independent variables. In this study, only the fine dust concentration is used as an independent variable. However, it is expected that a more clear and well-explained result can be found by adding appropriate additional variables to increase the explanatory power.

Evaluation of Fine Dust Diffusion and Contamination Degree : Focused on the Operation Status of Donghae Port (항만 인근 미세먼지 노출 영향권 및 오염도 분석 :동해항 운영현황을 중심으로)

  • Hwang, Je-Ho;Kim, Si-Hyun;Kang, Dal-Won
    • Journal of Navigation and Port Research
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    • v.46 no.3
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    • pp.251-258
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    • 2022
  • Donghae Port is adjacently located to a residential area wherein 26,933 generations are creating a living environment. The areas comprise Song-jeong village (5,754 generations) and Bukp-yeong village (21,179 generations). Major cargoes handled in Donghae Port are dusty limestone, cement, anthracite, and bituminous coal, etc. In the process of handling such cargoes, air pollutants including oxide dust and fine dust which adversely impact the living conditions and health of residents are generated, causing air pollution in the vicinity of the port. Currently, Donghae Port is making an effort to improve the operation environment of the infrastructure and equipment in stages, for the purpose of reducing air pollutant emissions caused by the port industries in a long-term perspective. In this study, the sphere of influence of fine dust exposure and the degree of air pollution in the surrounding area were analyzed such as the state of fine dust concentration and diffusion in the vicinity of Donghae Port, fine dust diffusion pattern and spatial distribution of high-concentration considering wind direction and speed characteristics during the day and seasonal cycles. A more effective plan to reduce the concentration of fine dust in nearby areas by combining reduction plan, is being developed in terms of improvement regarding port infrastructure and equipment, and reduction measures considering the characteristics of the atmosphere environment according to the daytime, nighttime and season.

Development of an air purification system using moss and evaluation of air purification capability for each moss (이끼를 활용한 공기정화 시스템 개발 및 이끼별 공기정화 능력 평가)

  • Ahn, DoHyun;Choi, Hyeunwoo;Lee, JongMin;Heo, SungPhil
    • Journal of Korea Society of Industrial Information Systems
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    • v.27 no.3
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    • pp.21-28
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    • 2022
  • Fine dust enters the lungs or blood vessels through the respiratory tract through the air. Recently, due to the fine dust problem, the demand for air purifiers in Korea is also increasing rapidly. Moss is the oldest terrestrial plant, and it is known that it has the property of adsorbing and decomposing heavy metals and fine dust. To compare the effect of reducing fine dust between moss and the existing chemical filter (Hepa), a cube of 1 m3 was manufactured and the amount of fine dust reduction under a controlled environment was compared. Under the fine dust conditions, an umbrella moss filter, rat tail moss filter, feather moss filter, and silk moss filter were inserted for a total of 40 experiments, 10 times each in 4 different situations. The difference between the amount after 30 minutes was statistically significant for all filters. However, as a result of the test, it was confirmed that there was no statistically significant difference between filters for fine dust, mixed gas, CO2, and O2. In particular, it was confirmed that the previously claimed effect of oxygen generation was almost nonexistent. Through this result, it was confirmed that the reduction of fine dust is effective regardless of the species view of moss, and it is expected to replace or supplement the chemical filter of the existing air purifier through future improvement.