• Title/Summary/Keyword: Aerosol measurement

Search Result 239, Processing Time 0.023 seconds

Validation for SOC Estimation from OC and EC concentration in PM2.5 measured at Seoul (서울 대기 중 PM2.5 내 OC와 EC로부터 SOC 추정방법의 비교 평가)

  • Yoo, Ha Young;Kim, Ki Ae;Kim, Yong Pyo;Jung, Chang Hoon;Shin, Hye Jung;Moon, Kwang Ju;Park, Seung Myung;Lee, Ji Yi
    • Particle and aerosol research
    • /
    • v.16 no.1
    • /
    • pp.19-30
    • /
    • 2020
  • The organic carbon in the ambient particulate matter (PM) is divided into primary organic carbon (POC) and secondary organic carbon (SOC) by their formation way. To regulate PM effectively, the estimation of the amount of POC and SOC separately is one of important consideration. Since SOC cannot be measured directly, previous studies have evaluated determination of SOC by the EC tracer method. The EC tracer method is a method of estimating the SOC value from calculating the POC by determining (OC/EC)pri which is the ratio of the measured values of OC and EC from the primary combustion source. In this study, three different ways were applied to OC and EC concentrations in PM2.5 measured at Seoul for determining (OC/EC)pri: 1) the minimum value of OC/EC ratio during the measurement period; 2) regression analysis of OC vs. EC to select the lower 5-20% OC/EC ratio; 3) determining the OC/EC ratio which has lowest correlation coefficient value (R2) between EC and SOC which is reported as minimum R squared method (MRS). Each (OC/EC)pri ratio of three ways are 0.35, 1.22, and 1.77, respectively from the 1 hourly data. We compared the (OC/EC)pri ratio from 1hourly data with 24 hourly data and revealed that (OC/EC)pri estimated from 24 hourly data had twice larger than 1hourly data due to the low time resolution of sampling. We finally confirmed that the most appropriate value of (OC/EC)pri is that calculated by a regression analysis of 1 hourly data and estimated SOC amounts at PM2.5 of the Seoul atmosphere.

A study on the monitoring of high-density fine particulate matters using W-station: Case of Jeju island (W-Station을 활용한 고밀도 초미세먼지 모니터링 연구: 제주도 사례)

  • Lee, Jong-Won;Park, Moon-Soo;Won, Wan-Sik;Son, Seok-Woo
    • Particle and aerosol research
    • /
    • v.16 no.2
    • /
    • pp.31-47
    • /
    • 2020
  • Although interest in air quality has increased due to the frequent occurrence of high-concentration fine particulate matter recently, the official fine particulate matter measuring network has failed to provide spatial detailed air quality information. This is because current measurement equipment has a high cost of installation and maintenance, which limits the composition of the measuring network at high resolution. To compensate for the limitations of the current official measuring network, this study constructed a spatial high density measuring network using the fine particulate matter simple measuring device developed by Observer, W-Station. W-Station installed 48 units on Jeju Island and measured PM2.5 for six months. The data collected in W-Station were corrected by applying the first regression equation for each section, and these measurements were compared and analyzed based on the official measurements installed in Jeju Island. As a result, the time series of PM2.5 concentrations measured in W-Station showed concentration characteristics similar to those of the environmental pollution measuring network. In particular, the results of comparing the measurements of W-Station within a 2 km radius of the reference station and the reference station showed that the coefficient of determination (R2) was 0.79, 0.81, 0.67, respectively. In addition, for W-Station within a 1 km radius, the coefficient of determination was 0.85, 0.82, 0.68, respectively, showing slightly higher correlation. In addition, the local concentration deviation of some regions could be confirmed through 48 high density measuring networks. These results show that if a network of measurements is constructed with adequate spatial distribution using a number of simple meters with a certain degree of proven performance, the measurements are effective in monitoring local air quality and can be fully utilized to supplement or replace formal measurements.

Distribution of Surface Solar Radiation by Radiative Model in South Korea (복사 모델에 의한 남한의 지표면 태양광 분포)

  • Zo, Il-Sung;Jee, Joon-Bum;Lee, Won-Hak;Lee, Kyu-Tae;Choi, Young-Jean
    • Journal of Climate Change Research
    • /
    • v.1 no.2
    • /
    • pp.147-161
    • /
    • 2010
  • The temporal and spatial distributions of surface solar radiation were calculated by the one layer solar radiative transfer model(GWNU) which was corrected by multi layer Line-by-Line(LBL) model during 2009 in South Korea. The aerosol optical thickness, ozone amount, cloud fraction and total precipitable water were used as the input data for GWNU model run and they were retrieved from Moderate Resolution Imaging Spectrometer(MODIS), Ozone Monitoring Instrument(OMI), MTSAT-1R satellite data and the Regional Data Assimilation Prediction System(RDAPS) model result, respectively. The surface solar radiation was calculated with 4 km spatial resolution in South Korea region using the GWNU model and the results were compared with surface measurement(by pyranometer) data of 22 KMA solar sites. The maximum values(more than $5,400MJ/m^2$) of model calculated annual solar radiation were found in Andong, Daegu and Jinju regions and these results were corresponded with the MTSAT-1R cloud amount data. However, the spatial distribution of surface measurement data was comparatively different from the model calculation because of the insufficient correction and management problems for the sites instruments(pyranometer).

Distribution of Culturable Bacteria of Bioaerosol according to Land Type in Winter in the City Center (도심지 겨울철 토지피복 유형별 바이오에어로졸 중 배양성 세균 분포)

  • Kim, Jeong-Ho;Yun, Yong-Han;Kim, Hak-Gi;Lee, Myeong-Hun;Park, Yeong-jin;Lee, Dong-Jae;Sin, Yong-jin
    • Korean Journal of Environment and Ecology
    • /
    • v.35 no.6
    • /
    • pp.669-678
    • /
    • 2021
  • This study surveyed three land cover types in Chungju City in Chungcheongbuk Province to check the distribution of cultured bacteria in bio-aerosols according to land cover type. It was possible to compare and analyze the distribution of bacteria according to microclimatic changes at each measurement point by examining meteorological factors and bio-aerosols according to land cover. The microclimate temperature in each measurement point was 8.7℃ for the urban forest, 10.8℃ for the waterside green area, and 10.2℃ for the urban area, indicating the urban forest had the lowest temperature among the measurement points. The relative humanity was 61.8% fin the urban forest, 59.3% in the waterside green area, and 55.7% in the urban area, indicating that the urban forest was the most humid among the measurement points. The identified bacteria were found to be 43 genera and 99 species. In terms of species diversity of cultured bacteria, 22 genera were found in the waterside green area, 21 genera in the urban forest, and 17 genera in the urban area, 37 species were found in the waterside green area, 31 species in the urban area, and 31 species in the urban forest. Bacillus toyonensis and Pseudarthrobacter oxydan were the species present in all three types of measurement sites, and Herbiconiux flava was confirmed to inhabit green areas such as urban forests and waterside green areas. The analysis result of the bacterial concentration according to the microclimatic environment in each measurement point was 333 CFU/m3 in the urban forest, 287 CFU/m3, in the waterside green area, and 173 CFU/m3 in the downtown area. The relative humidity and wind speed were analyzed to show a similar trend as the concentration. This study is expected to provide basic data for healthy urban management and green area creation by identifying the distribution of cultured bacteria in bio-aerosols according to land cover type and comparing and analyzing the traits of bio-aerosol in each measurement point.

Properties of Roadway Particles from the Interaction between Tire and Road Pavement (차량 주행 과정에서 타이어와 도로의 마찰에 의해서 발생하는 도로입자의 특성연구)

  • Lee, Seok-Hwan;Kim, Hong-Seok;Park, Jun-Hyuk;Woo, Se-Jong;Kwak, Ji-Hyun
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.20 no.6
    • /
    • pp.24-32
    • /
    • 2012
  • A large fraction of urban $PM_{10}$ concentrations is due to non-exhaust traffic emissions including road dust, tire wear particles, and brake lining particles. Although potential health and environmental impacts associated with tire wear debris have been increased, few environmentally and biologically relevant studies of actual tire wear debris have been conducted. Tire wear particles (TWP) are released from the tire tread as a result of the interaction between the tire and the pavement. Roadway particles (RP), meanwhile, are particles on roads composed of a mixture of elements from tires, pavements, fuels, brakes, and environmental dust. The main objective of present study is to identify the contribution of tires to the generation of RP and to assess the potential environmental and health impacts of this contribution. First, a mobile measurement system was constructed and used to measure the roadway particles on asphalt road according to vehicle speed. The equipment of the mobile system provides $PM_{10}$ concentrations by Dusttrak DRX and number density & size distribution measurements of fine and ultra-fine particles by a fast mobility particle sizer (FMPS) and an aerosol particle sizer (APS). When traveling on an asphalt road at constant speed, there is a clear tendency for PM10 concentration to increase slightly in accordance with an increase in the vehicle speed. It was also found that considerable brake wear particles and particles from tire/road interface were generated by rapid deceleration of the vehicle. The morphology and elements of the roadway particles were also analyzed using SEM-EDX technique.

Characteristics of TSP Concentrations Measured at Gosan: Statistical Analysis (고산에서 측정한 TSP 농도 특성: 통계적 해석)

  • 박민하;김용표;강창희;김원형
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.19 no.1
    • /
    • pp.93-100
    • /
    • 2003
  • In this technical information, the long-term measurement data at Gosan between 1992 and 2001 are analyzed with various statistical methods. First. it was confirmed that the basic assumption of t-test is important to classify data correctly. Second, it was founded that the difference of the number of data per month can affect the averaged concentration. Third, by using a non-parametric statistical method long term trend of aerosol composition free from seasonal effects is obtained.

Effects of Asian Dust (KOSA) Deposition Event on Bacterial and Microalgal Communities in the Pacific Ocean

  • Maki, Teruya;Ishikawa, Akira;Kobayashi, Fumihisa;Kakikawa, Makiko;Aoki, Kazuma;Mastunaga, Tomoki;Hasegawa, Hiroshi;Iwasaka, Yasunobu
    • Asian Journal of Atmospheric Environment
    • /
    • v.5 no.3
    • /
    • pp.157-163
    • /
    • 2011
  • Atmospheric aerosol deposition caused by Asian dust (KOSA) events provide nutrients, trace metals, and organic compounds over the Pacific Ocean that enhance ocean productivity and carbon sequestration and, thus, influence the atmospheric carbon dioxide concentrations and climate. Using dust particles obtained from the snow layers on Mt. Tateyama and the surface sand of Loess Plateau in incubation experiments with natural seawater samples on a shipboard, we demonstrate that dust-particle additions enhanced the bacterial growth on the first day of incubation. Gram-positive bacterial group and alpha-proteobacteria were specifically detected form seawater samples including the mineral particles. Although the remarkable dynamics of trace elements and nutrients depend on dust-particle additions, it is possible that organic compounds present in the mineral particles or transported microbial cells could also contribute to an increase in the quantities of bacteria. The chlorophyll concentrations at fractions of every size indicated a similar pattern of change between the seawater samples with and without the dust-particle additions. In contrast, the chlorophyll measurement using submersible fluorometer revealed that the dynamics of phytoplankton composition were influenced by the dust-particles treatments. We conclude that the phytoplankton that uses the bacterial products would increase their biomass. We show that KOSA deposition can potentially alter the structures of bacterial communities and indirectly influence the patterns of marine primary production in the Pacific Ocean.

Measurement and Analysis of Dust Concentration in a Fattening Pig House Considering Respiratory Welfare of Pig Farmers (비육돈사 작업 종사자의 호흡기 관련 공기 중 분진 농도 측정 및 분석)

  • Kwon, Kyeong-Seok;Lee, In-Bok;Hwang, Hyun-Seob;Ha, Tae-Hwan;Ha, Jung-Soo;Park, Se-Jun;Jo, Ye-Seul
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.55 no.5
    • /
    • pp.25-35
    • /
    • 2013
  • In swine house, dust generation comes from various sources and is known to be harmful both for the animals and the farmers because the dust contains biological and gaseous matters. When farmers are constantly exposed to the dusts, they can suffer chronic or acute respiratory symptoms and have high probability of manifesting various diseases. To address this problem, understanding of the mechanism of dust generation is very important. In this paper, the dust concentration of inhalable, respirable, TSP and $PM_{10}$ were monitored and analyzed according to the pig-activity level, ventilation quantity and feeding method in fattening pig house. From the measured results, in case of the concentration of TSP, an inverse-linear relation with ventilation rate ($R^2=0.88$) and linear relation with the installation height of feed supply pipe ($R^2=0.73$) were determined. However in case of the concentration of $PM_{10}$, no particular relationship with the variables was observed. Using the concentration of inhalable and respirable dust based on the pig-activity level, multi-variate regression analysis was conducted and results have shown that the movement of pigs can contribute to the dust generation (p<0.05, $R^2=0.71$, 0.61). The relationship determined between dust generation and environmental variables investigated in this study is very significant and useful in conducting dust-reduction researches.

Comparative Evaluation of Gravimetric Measurement Methods for Suspended Particles in Indoor and Outdoor Air (실내.외 공기 중 부유먼지 측정방법 상호간의 비교평가 - 중량법을 대상으로)

  • 백성옥;박지혜;서영교
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.18 no.4
    • /
    • pp.285-295
    • /
    • 2002
  • In this study, several types of gravimetric methods (such as high, medium, low, and ultra low volume sampling methods) were applied to determine suspended particulate matter concentrations in both ambient and indoor environments. Comparative evaluations were undertaken with SPM data obtained using a variety of samplers (TSP, PM10, and PM4.0) at different sampling flow rates. Correlation coefficients between TSP and PM10 concentrations measured at different flow rates fell in the range of 0.73∼0.94 (n=40). In addition, correlation coefficients for PM concentrations measured by different TSP samplers were in the range of 0.90∼0.95 (n=36 or n=38), while 0.77∼0.91 (n=38) for PM10 samplers. Correlation analysis was also conducted on indoor monitoring data that were measured using ultra-low-volume samplers at both different or identical flow rates. The correlation coefficients were in the range of 0.98∼0.99 (n=38) between TSP and TSP and 0.92∼0.94 (n=38) between TSP and PM10. The mean ratio for high volume PM10 to TSP concentration that was monitored at identical flow rates in the ambient air appeared to be 0.72. The mean ratios of PM10 to TSP and PM4.0 to TSP observed with identical flow rates at indoor environments were 0.47 and 0.40. The results of this study may provide empirical information concerning the compatability of aerosol data obtained by gravimetric sampling methods at different flow rates.

The Properties of Roadway Particles from the Interaction between the Tire and the Road Pavement (실제 도로 주행과정에서 타이어와 도로의 마찰에 의해서 발생하는 미세입자의 특성연구)

  • Lee, Seok-Hwan;Kim, Hong-Suk;Park, Jun-Hyuk;Cho, Gyu-Baek
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.28 no.2
    • /
    • pp.131-141
    • /
    • 2012
  • A large fraction of urban $PM_{10}$ concentrations is due to non-exhaust traffic emissions including road dust, tire wear particles, and brake lining particles. Although potential health and environmental impacts associated with tire wear debris have increased, few environmentally and biologically relevant studies of actual tire wear debris have been conducted. Tire wear particles (TWP) are released from the tire tread as a result of the interaction between the tire and the pavement. Roadway particles (RP), meanwhile, are particles on roads composed of a mixture of elements from tires, pavements, fuels, brakes, and environmental dust. The main objective of present study is to identify the contribution of tires to the generation of RP and to assess the potential environmental and health impacts of this contribution. First, a mobile measurement system was constructed and used to measure the RP on asphalt roads according to vehicle speed. The equipment of the mobile system provides $PM_{10}$ concentrations by Dusttrak DRX and number density & size distribution measurements of fine and ultra-fine particles by a fast mobility particle sizer (FMPS) and an aerosol particle sizer (APS). When traveling on an asphalt road at constant speed, there is a clear tendency for $PM_{10}$ concentration to increase slightly in accordance with an increase in the vehicle speed. It was also found that considerable brake wear particles and particles from tire/road interface were generated by rapid deceleration of the vehicle. As a result, the $PM_{10}$ concentration and particle number of ultra-fine particles were measured to be very high.