• 전기학회논문지
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• 제56권1호
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• pp.28-34
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• 2007

Recently, with the rapid growth of industry, environmental condition became worse. In addition to outdoor insulators in seashore are polluted due to salty wind. Also this pollution causes the flashover and failure of electric equipments. Especially the salt contaminant is one of the most representative pollutants, and known as the main source of the accident by contamination. As well known, the pollution has a close relation with meteorological factors such as wind velocity, wind direction, temperature, relative humidity, precipitation and so on. In this paper we have statistically analyzed the correlation between the pollution and the meteorological factors. The multiple regression analysis was used for the statistical analysis; daily measured equivalent salt deposit density(dependent variable) and the weather condition data(independent variable) were used. Also we have developed an expert program to predict the pollution deposit. A new prediction system using this program called SPPP(salt pollution prediction program) has been used to model accurately the relationship between ESDD with the meteorological factors.

• 한국대기환경학회지
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• 제29권6호
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• pp.745-756
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• 2013

The purpose of this study is to evaluate representativeness of fuel-based emission factors. Twelve light-duty diesel vehicles which meet Euro-3 to 5 legislative emission limits were selected for emission tests. Second-by-second modal emission rates of vehicles were measured on a standard laboratory chassis dynamometer system. An off-cycle driving cycle was developed as a representative Korean real-world on-road driving cycle. Fuel-based emission factors were developed for short trip segments that involved in the selected driving cycle. Each segment was defined to have unit travel distance, which is 1 km, and characterized by its average speed and Relative Positive Acceleration (RPA). Fuel-based $NO_x$ emission factors demonstrate relatively good representativeness in terms of vehicle operation conditions. $NO_x$ emission factors are estimated to be within ${\pm}20%$ of area-wide emission factor under more than 40% of total driving situations. This result implies that the fuel-based $NO_x$ emission factor could be practically implemented into the on-road emission management strategies, such as a remote sensing device (RSD). High emitting vehicles as well as high emitting operating conditions heavily affect on the mean values and distributions of CO and THC emission factors. Few high emitting conditions are pulling up the mean value and biasing the distributions, which weaken representativeness of fuel-based CO and THC emission factors.

• 한국대기환경학회지
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• 제33권4호
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• pp.351-360
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• 2017

In this study, we developed emission factors from solid-fuel fired combustors. In order to increase the reliability of emission factors, we conducted a joint research with the Institute of Health and Environment. As a result, PM average concentration was $8.19mg/m^3$. $SO_2$ and $NO_x$ were respectively 8.46 ppm, 50.64 ppm. Hazardous air pollutants such as Cr, Pb and Hg were detected in trace amounts continuously for 2 years in some solid-fuel fired combustors. The emission factors for the three kinds of PM, $SO_x$, $NO_x$ were developed based on the measurement data. For the PM emission factors, that of SRF was 15.93 g/kg and that of Bio-SRF was 14.18 g/kg. Compared with those of US. EPA, emission factors of this study showed the results of low values. $SO_x$ emission factors were 4.42 g/kg for SRF and 1.39 g/kg for Bio-SRF. $NO_x$ emission factors were 13.21 g/kg and 4.43 g/kg, respectively. Through the results of this study, we would support atmospheric administration policies such as the emission factor notification revision.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1802-1804
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• 2004

In seashore, outdoor insulators are polluted due to salty wind and the pollution causes the flashover and failure of electric equipments. As well known, the pollution has a close relation with meteorological factors such as wind velocity, precipitation, wind direction, relative humidity, dew point, etc. In this paper we statistically analyzed the correlation between the pollution and the meteorological factors including snowfall and freezing. The multiple regression analysis was used for the statistical analysis; daily measured equivalent salt deposit density(dependent variable) and the meteorological data(independent variable) were used. From the results of this investigation, we verified the influence of snowfall and freezing on the ESDD, which has been overlooked in the preceding investigation.

• 한국대기환경학회지
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• 제33권2호
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• pp.77-86
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• 2017

Globally, use of affordable fuels such as briquettes, woods and wood pellets has increased. Organic pollutants emitted from non-point sources using solid fuels may have contributed to air pollution in urban environment. In this study, we utilized simulated incinerator proposed by U.S. EPA and investigated concentrations of PM, $PM_{10}$, $PM_{2.5}$, OC/EC, CO, $SO_x$, $NO_x$, VOCs and PAHs emitted while cooking meat and fish using briquettes, woods and wood pellets, and developed emission factors. As a result, wood combustion produced more air pollutants than the others. Particulate matter emission factors for woods and wood pellets were 13.54 g/kg and 9.15 g/kg, respectively. Total VOCs emission factors for briquettes, woods and wood pellets were 36.12mg/kg, 46.13mg/kg and 18.26mg/kg, respectively. Additionally, total PAHs emission factors for briquette, woods and wood pellets were 0.44 mg/kg, 18.84mg/kg and 101.62mg/kg, respectively.

• Environmental Engineering Research
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• 제20권3호
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• pp.260-267
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• 2015

The $PM_{10}$, $SO_2$ and $NO_2$ mass concentrations were obtained over five years from monitoring stations across Nanchong, a southwest city in China. Changes in urban air quality over time, as well as the factors influencing that change, were evaluated based on air pollutant concentrations, the Air Pollution Index (API), and the Comprehensive Pollution Index (P). The results showed that the total annual mean $PM_{10}$, $SO_2$ and $NO_2$ concentrations over the five years studied were $61.1{\pm}1.1$, $45.0{\pm}3.9$ and $34.9{\pm}4.9{\mu}g{\cdot}m^{-3}$, respectively. The annual mean concentrations displayed a generally decreasing trend; lower than the annual mean second-level air quality limit. Meanwhile, the annual mean API values were in a small range of 52-53, the air quality levels were grade II, and P values were 1.06-1.21 less than the slight level ($P{\leq}1.31$). Total monthly mean $PM_{10}$, $SO_2$, $NO_2$ concentrations, and API and P values were consistently higher in winter and spring than during autumn and summer. The results of a correlation analysis showed that temperature and pressure were the major meteorological factors influencing pollution levels. Pollution sources included industrial coal and straw burning, automobiles exhaust and road dust, fireworks, and dust storms.

• 한국물환경학회지
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• 제32권3호
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• pp.281-290
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• 2016

In the northernmost basin of the Bukhan River, pollution sources can have a concentrated distribution. In these basins, small streams show low flow with various and rapid water quality change in low pollutants load. Therefore, a water quality improvement plan of small streams and main stem will be necessary to establish the characteristics of small streams. This study selected a representative Hwacheon-gun in the northernmost basin of the Bukhan River. Hydro analysis was performed with GIS tools using DEM. A total of 152 small streams were listed. A total of 51 survey locations were selected after applying the selection criteria. Flow rate and water qualities were investigated. Pollution sources and pollutants loads were calculated for each basin. Pollution grade and typological classification were performed by cluster analysis using standardized environmental condition factors. As a result, G04, G01, H01 locations were found to have the worst pollution grades whereas J01, P01, and P02 had less pollution. Typological analyses were able to classify six types for the surveyed small streams. An effective water quality improvement plan was obtained based on the results of pollution grade and typological analysis using environmental condition factors of this study.

• 한국과학교육학회지
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• 제13권2호
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• pp.272-281
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• 1993

The purpose of this study was. to develop a valid and reliable Likert-type scale to assess middle school students' attitude toward environmental pollution. The evaluation categories of this instrument were cognition and conaction levels. Initially, 42 statements (29 statements for cognition level and 13 statements for conaction level) were framed. This pilot instrument was administered to 1015 middle school students. To select valid and reliable statements, the 42 initial statements were analyzed by item mean, standard deviation, and response distribution. In addition, the emotional intensity: of each statement was judged. As a result, 22 final statements (14 statements for cognition level and 8 statements for conaction level) were developed. Cronbach alpha coefficient of the instrument was 0.76 with a range of item-total correlation from 0.229 to 0.488. Factor analysis was done to explore the potential constructs of this instrument. As a result, six factors were extracted. Those factors were identified as "Conaction to prevent environmental pollution", "Confrontation with the enterprise which causes environmental pollution", "Voluntary inclination to participate in the group which prevents environmental pollution", "Discussion on environmental pollution", "Environmental pollution and interests", and "Everyday sources of environmental pollution".

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2018년도 공동국제학술발표회
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• pp.51-51
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• 2018

• 한국대기환경학회지
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• 제25권3호
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• pp.188-195
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• 2009

Generally. mobile sources of air pollution were classified in on-road and non-road. Due to increased registration number of construction equipment in Korea. updated emission factors for non-road mobile sources, such as construction machinery. should be developed. NONROAD model of U.S. EPA already has introduced transient adjustment factors and sulfur adjustment factors for emission factors of diesel powered engine. In addition to this. European Environment Agency (EEA) has proposed emission factors for off-road machinery including several types of construction equipment. In this study. six types of construction equipment, such as excavator. forklift, loader, crane, roller and bulldozer, were studied to estimate emission factors based on total registration status in Korea. Total 445 construction equipments between 2004 and 2007 model year were tested with KC1-8 mode and air pollutants (CO, THC, $NO_x$, and PM) were measured. After statistical estimation and calculation, emission factors for CO, THC, $NO_x$, and PM for excavator, forklift, loader, crane, roller and bulldozer were provided and compared with previous emission factors. Moreover, updated emission factors for six types of construction equipment in this study were verified after comparison with emission factors of U.S. EPA. Finally, estimated emission amounts of four air pollutants were suggested according to six types of construction equipment.