• Title/Summary/Keyword: Roadside air

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모바일 오피스 서비스 지원을 위한 ADSRC 패킷 통신 시스템

  • Lee, Hyun;An, Dong-Hyun;Shin, Chang-Sub;Im, Chun-Sik;Park, Se-Ho;Cho, Kyung-Rok
    • Information and Communications Magazine
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    • v.19 no.9
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    • pp.77-85
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    • 2002
  • In this paper, we introduce an ADSRC(hdvanced DSRC) OFDM packet communication system which has been developed by ETRI. The ADSRC system is targeted to provide high terminal mobility, high data rate and seamless service in roadside environment for mobile office services. We discuss the requirements of the ADSRC communication system for mobile office services, and the system design specification to meet them with regard to air interface. The ADSRC packet communication systems consist of the MAC processor block, the OFDM packet modem block and the RF block. The MAC processor block handles medium access control and the test. The OFDM packet modem transmits data packets at up to 24Mbps adaptively and recovers the data from RF block. We describe the ADSRC packet communication system architecture and the ADSRC system protocol.

A Study on the Airborne Concentration of Heavy Metals by INAA at the Roadside (INAA를 이용한 도로변의 중금속 농도에 관한 연구)

  • 임종명;구부미;장미숙;이진홍
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.11a
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    • pp.35-36
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    • 2000
  • 교통수단의 발달과 경제활동이 활발해짐에 따라 많은 오염문제가 발생하였는데, 특히 대도시를 중심으로 증가한 차량과 경제활동에 필요한 에너지 소비의 증대로 대기오염의 심각성은 더욱 커지게 되었다. 일반적으로 대기중 부유 분진의 발생원은 토사의 재 비산이나 해염 입자, 화분 등과 같은 자연적인 발생원과 산업시설, 소각시설, 가정난방, 수송수단의 이용 등의 인간활동에 의한 인위적인 배출원으로 대별되며 인위적인 배출원의 영향은 자연적 발생원에 비해 그 영향이 보다 폭넓고 중요하게 다루어지고 있으며, 특히 화석연료의 연소와 관련 있는 각종 산업시설의 증가 및 대형 디젤 자동차의 급격한 증가는 대기 중 부유분진의 농도를 증가시키는 중요한 요인이 되고 있다. (중략)

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A Study on Heavy Metal Levels of PM 2.5 and Source Identification in Roadside Area (도로변 미세분진중 중금속의 농도특성과 오염원확인에 관한 연구)

  • 임종명;이현석;장미숙;이진홍;문종화;정용삼
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2002.04a
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    • pp.53-54
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    • 2002
  • 도시대기중의 분진은 입경 분포에 따라 공기 역학적 직경 2.5$\mu\textrm{m}$를 기준으로 미세 입자(fine particles)와 거대 입자(coarse particles)로 나누어지는 쌍극분포를 보인다. 미세 입자는 주로 화석연료의 연소, 자동차의 배기가스 등과 같은 인위적 발생원에 의한 것이며, 거대입자는 토사의 재 비산, 해염 통과 같은 자연적 발생원에 의한 것이다. 미세 입자는 오염된 도심지역 분진수의 90-99%에 이르는 높은 비율을 보이고 있고, 폐 깊숙히 침투하여 폐 질환을 일으킬 수 있다. (중략)

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PM3.5/NO$_2$ Concentration Ratio in Roadside and Exposure Assessment of Shoes Repairmen (도로변의 PM3.5/NO$_2$ 농도비 및 구두수선대 근로자의 노출평가)

  • 양원호;배현주;김나리;정문호
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2001.11a
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    • pp.273-274
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    • 2001
  • 세계 여러 나라에서는 구두를 닦거나 수선하는 직업에 종사하는 사람들이 있고 우리 나라 역시 그렇다. 그러나 우리 나라 구두기능 미화원들의 작업환경은 독특한 형태로서, 우리 나라는 1991년 8월부터 서울시내 도로변(人道)에 구두수선대라는 명칭으로 구두수선박스가 곳곳에 점유하고 있다. 본 연구는 도시지역 대기오염의 주 요인이 차량임을 고려하여 도로변 구두수선대 실내 및 실외의 PM3.5와 이산화질소(NO$_2$)를 측정하였고, PM3.5/NO$_2$ 농도비를 계산하였다. (중략)

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A Study on Water Soluble Ion Components of PM 10 in the Roadside Area of Daejeon City (대전시 도로변 대기중 수용성 이온성분에 관한 연구)

  • Jeon, Ryong;Lee, Jin-Hong;Lee, Jong-Hae;Min, Byung-Hun;Kim, Tae-Ho
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2002.04a
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    • pp.33-34
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    • 2002
  • 교통수단의 발달과 경제활동이 활발해짐에 따라 많은 오염문제가 발생하였는데, 특히 대도시를 중심으로 차량과 경제활동에 필요한 에너지 소비의 증대로 대기오염의 심각성은 더욱 커지게 되었다. 일반적으로 대기중 분진의 발생원은 토사의 재비산이나 해염입자, 화분 등과 같은 자연적인 발생인과 산업시설, 소각시설, 가정난방, 수송수단 이용 등의 인간활동에 의한 인위적인 배출원으로 대별된다. 그런데 환경오염 측면에서 보면 인위적인 배출원의 영향은 자연적 발생원에 비해 그 영향이 보다 폭넓고 중요하게 다뤄지고 있다. (중략)

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The Absorption and Purification of Air Pollutants and Heavy Metals by Selected Trees in Kwangju (광주지역(光州地域)에서 주요(主要) 수목(樹木)의 대기오염물질(大氣汚染物質)과 중금속(重金屬) 흡수(吸收) 정화기능(淨化機能)에 관(關)한 연구(硏究))

  • Cho, Hi Doo
    • Journal of Korean Society of Forest Science
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    • v.88 no.4
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    • pp.510-522
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    • 1999
  • The air pollutants ; $SO_2$, $SO{_4}^{-2}$, $NO{_3}^-$, $Cl^-$ are absorbed into soils through falling with dusts and rain from the atmosphere. The sources of heavy metal contaminants in the environments are agricultural and horticultural materials, sewage sludges, fossil fuel combustion, metallurgical industries, electronics and waste disposal etc.. The soils and hydrosphere can be polluted on the way of the circulation of these heavy metals. Studied pollutant anions are $SO{_4}^{-2}$, $NO{_3}^-$ and $Cl^-$ and heavy metals are Se, Mo, Zn, Cd, Pb, Mn, Cr, Co, V, As, Cu and Ni which are the elements to be concerned with the essentials for plants, with animal and human health. This study is with the aim of selecting the species of roadside trees and green space trees which have excellent absorption of air pollutants and heavy metals from the atmosphere and the soils in the urban area. Two areas are designated to carry out this study : urban area ; Kwangju city and rural area ; the yard of Forest Environment Institute of Chollanam-do, at Sanje-ri, Sampo-myum, Naju city, Chollanam-do (23km away from Kwangju). This study is carried out to understand the movement of anions and heavy metals from the soils to the trees in both areas, the absorption of anions and heavy metals from atmosphere into leaves and the amounts of anions and heavy metals in leaves and fine roots(< 1mm dia.) of roadside trees and green space trees in Kwangju and trees in the yard of Forest Environment Institute of Chollanam-do. The tree species selected for this study in both areas are Ginkgo biloba, Quercus acutissima, Cedrus deodara, Platanus occidentalis, Robinia pseudoacacia, Alnus japonica. Metasequoia glyptostroboides. Zekova serrata. Prunus serrulata var. spontanea, and Pinus densiflora. The results of the study are as follows : 1. $SO{_4}^{-2}$, $NO{_3}^-$ and $Cl^-$ concentrations are higher in the soils of the urban area than in those of the rural area, and $NO{_3}^-$ and $SO{_4}^{-2}$ are higher in the leaves than in the roots due to the absorption of the these pollutants through the stomata. 2. Ginkgo biloba, Robinia pseudoacacia. Zekova serrata, Quercus acutissima, and Platanus occidentalis can be adequated to the roadside trees and the environmental trees due to their good absorption of $NO{_3}^-$ and $SO{_4}^{-2}$. 3. Heavy metals in the soils of both areas are in the order of Mn > Zn > V > Cr > Pb > Ni > Cu > Mo> Cd, and in the leaves and roots of the trees in the both areas are in the order of Mn>Zn>Cr>Cu>V>Ni. Both orders are similar ones except V. There are more in the urban soils than in the rural soils in amount of Mn, Zn, Pb, V, Cu. 4. It is supposed that there is no antagonism between Mn and Zn in this study. 5. Se, Co and As are not detected in the soils, the leaves and the roots in both areas. Sn, Mo, Cd and Pb are also not detected in the leaves and roots in spite of considerable amount in the soils of both areas.

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Ambient Air Concentrations of Benzene, Toluene, Ethylbenzene and Xylene in Bangkok, Thailand during April-August in 2007

  • Laowagul, Wanna;Garivait, Hathairatana;Limpaseni, Wongpun;Yoshizumi, Kunio
    • Asian Journal of Atmospheric Environment
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    • v.2 no.1
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    • pp.14-25
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    • 2008
  • Benzene, toluene, ethyl benzene and m-, p-, and o-xylene, the most influential aromatic volatile organic compounds (VOCs), were measured in Bangkok, Thailand, one of the most rapidly developing urban areas in Southern East Asia. The purpose of this study is to characterize the ambient air quality with respect to above mentioned aromatic compounds. The data were monitored in ten sites which cover roadside area, residential area and background area. Canister technique was used to obtain air sample at 24 hour interval per a month during April-August in 2007. GC/MS with three stage preconcentrator was used to analyze these samples. The average concentrations of benzene, toluene, ethyl benzene m-, p-xylene and o-xylene are 5.8, 36.1, 4.1, 11.0 and $3.7{\mu}g/m^3$, respectively. They were observed to be distributed in a log-normal form. Moreover, o-xylene and m, p-xylene exhibited a very good correlation (r=0.976). The slope of the regression equation between them was 3.07 which consisted with a previous reported value. The average ratio of toluene to benzene was 6.4 in April, May June and August. This value was comparable to the ones measured in other Asian cities. Two types of statistical analyses, cluster and factor analyses, were applied to the data in this study. Well characterization was made to understand the air quality of Bangkok area.

Air Pollution Trends in Japan between 1970 and 2012 and Impact of Urban Air Pollution Countermeasures

  • Wakamatsu, Shinji;Morikawa, Tazuko;Ito, Akiyoshi
    • Asian Journal of Atmospheric Environment
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    • v.7 no.4
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    • pp.177-190
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    • 2013
  • Air pollution trends in Japan between 1970 and 2012 were analyzed, and the impact of air pollution countermeasures was evaluated. Concentrations of CO decreased from 1970 to 2012, and in 2012, the Japanese environmental quality standard (EQS) for CO was satisfied. Concentrations of $SO_2$ dropped markedly in the 1970s, owing to use of desulfurization technologies and low-sulfur heavy oil. Major reductions in the sulfur content of diesel fuel in the 1990s resulted in further decreases of $SO_2$ levels. In 2012, the EQS for $SO_2$ was satisfied at most air quality monitoring stations. Concentrations of $NO_2$ decreased from 1970 to 1985, but increased from 1985 to 1995. After 1995, $NO_2$ concentrations decreased, especially after 2006. In 2012, the EQS for $NO_2$ was satisfied at most air quality monitoring stations, except those alongside roads. The annual mean for the daily maximum concentrations of photochemical oxidants (OX) increased from 1980 to 2010, but after 2006, the $98^{th}$ percentile values of the OX concentrations decreased. In 2012, the EQS for OX was not satisfied at most air quality monitoring stations. Non-methane hydrocarbon (NMHC) concentrations generally decreased from 1976 to 2012. In 2011, NMHC concentrations near roads and in the general environment were nearly the same. The concentration of suspended particulate matter (SPM) generally decreased. In 2011, the EQS for SPM was satisfied at 69.2% of ambient air monitoring stations, and 72.9% of roadside air-monitoring stations. Impacts from mineral dust from continental Asia were especially pronounced in the western part of Japan in spring, and year-round variation was large. The concentration of $PM_{2.5}$ generally decreased, but the EQS for $PM_{2.5}$ is still not satisfied. The air pollution trends were closely synchronized with promulgation of regulations designed to limit pollutant emissions. Trans-boundary OX and $PM_{2.5}$ has become a big issue which contains global warming chemical species such as ozone and black carbon (so called SLCP: Short Lived Climate Pollutants). Cobeneficial reduction approach for these pollutants will be important to improve both in regional and global atmospheric environmental conditions.

Scenario-Based Analysis on the Effects of Green Areas on the Improvement of Urban Thermal Environment (녹지 조성 시나리오에 따른 도시 열환경 개선 효과 분석)

  • Min, Jin-Kyu;Eum, Jeong-Hee;Sung, Uk-Je;Son, Jeong-Min;Kim, Ju-Eun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.50 no.6
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    • pp.1-14
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    • 2022
  • To alleviate the urban heat island phenomenon, this study aims to quantitatively analyze the effects of neighborhood green spaces on the improvement of the thermal environment based on detailed scenarios of five types of green spaces, including parks, pocket parks, parking lot greening, roadside planting, and rooftop-wall greening. The ENVI-met 4.4.6v model, a microclimate simulation program, was used to analyze the effects of green spaces. As a result, it was found that the air temperature decreased as the planting density of the park increased, but the thermal comfort index PET, which is the degree of heat sensation felt by humans, was not directly proportional to temperature. The establishment of a pocket park reduced air temperature up to a radius of 56m, while the range of temperature reduction increased by about 12.5% when three additional pocket parks were established at 250m intervals. Unlike the air temperature, PET was only affected in the vicinity of the planted area, so there was no significant difference in the thermal comfort of the surrounding environment due to the construction of pocket parks. Changing the surface pavement from asphalt to lawn blocks and implementing rooftop or wall greening did not directly act as solar shading but positively affected air temperature reduction; PET showed no significant difference. Roadside planting showed a higher air temperature reduction effect as the planting interval was narrower, but PET was not directly proportional to tree density. In the case of shrub planting under trees, it did not significantly affect the air temperature reduction but positively affected the improvement of thermal comfort. This study can outline strategies for constructing neighborhood green spaces to solve the urban heat island phenomena and establish detailed strategies for efficient thermal environment improvements.

Effect of Air Pollution on Cherry Tree (Prunus yedoensis Matsumara) Planted on National Roadsides between Cheonju and Kunsan City(II) - Chlorophyll, Magnesium and Sodium Contents in the Leaves - (대기오염(大氣汚染)이 전주(全州)-군산간(群山間) 국도변(國道邊) 왕벚나무에 미치는 영향(影響)(II) - Chlorophyll, Mg 및 Na 함유량(含有量)을 중심으로 -)

  • Hwang, Yu Chul;Kim, Chang Ho;Yim, Kyong Bin
    • Journal of Korean Society of Forest Science
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    • v.81 no.3
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    • pp.224-233
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    • 1992
  • This report succeds the previous paper, the source of materials and statistical designs used were not altered. Under the hypothesis of maleffect of atmospheric pollutions emitted mainly by traffic automobiles on 20-year-old, Prunus yedoensis roadside trees planted along national road between Cheonju abd Kunsan, chlorophyll a and b contents, magnesium and sodium contents of leaves were analysed on September 15. Besides control sites considered to be a pollution free district, 20 polluted road-side sites, 10 on left roadside and 10 on right roadside, oppositely faced in pairs were selected. The leaves collected from 5 trees at each sampling site were bulked to eliminate the individual tree variation. Chlorophyll were extracted by Mackinney and Arnon method. The results obtained are as follows : 1. The planting belt width between road shoulder and paved road face edge for cherry trees, 160~170cm, was considered too narrow for the growing space. 2. On an average, the total chlorophyll content between Cheonju and Iri($8.60{\sim}9.31ml/cm^2$) was lower than that for between Iri and Kunsan($9.24{\sim}10.74ml/cm^2$). 3. The chlorophyll b content showed the difference, higher on right roadside and lower on left side. However this difference could be confirmed by matched pair T-test at 10% level. 4. Without exception, the chlorophyll contents of control sites were higher than those of road-side trees, implying the maleffect of atmospheric pollutants on cherry tree growth. 5. On the contrary, magnesium and sodium contents of the leaves of road-side trees were higher than that of control site trees.

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