• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.1
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• pp.1-10
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• 2008

A transient 3-D numerical simulation was performed to analyze the fire safety in a railway tunnel equipped with a mechanical ventilation system. The behavior of pollutants was studied for the emergency operation mode of ventilation system in case of fire in the center of the rescue station and near the escape route. Various schemes of escape route construction for connection angle($45^{\circ}$, $90^{\circ}$, 135^{\circ}$) and slope($10^{\circ}$) were evaluated for the ventilation efficiency in the fire near the escape route. From the results, it was shown that the mode of the ventilation fan operation which pressurizes the tunnel not under the fire and ventilates the smoke from the tunnel under the fire is most effective for the smoke control in the tunnel in case of the fire occurrence. It was also shown that the blowing of jet fan from the rescue tunnel to the main tunnel should be in the same direction as the flow direction in the main tunnel arising from the traffic and the buoyancy.

• Journal of Cadastre & Land InformatiX
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• v.51 no.2
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• pp.141-150
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• 2021

Fine dust is a substance that greatly affects human health, and various studies have been conducted in this regard. Due to the human influence of particulate matter, various studies are being conducted to predict particulate matter grade using past data measured in the monitoring network of Seoul city. In this paper, predictive model have focused on particulate matter concentration in May, 2019, Seoul. The air pollutant variables were used to training such as SO₂, CO, NO₂, O₃. The predictive model based on Adaboost, and training model was dividing PM₁₀ and PM_2.5. As a result of the prediction performance comparison through confusion matrix, the Adaboost model was more conformable for predicting the particulate matter concentration grade. Although air pollutant variables have a higher correlation with PM2.5, training model need to train a lot of data and to use additional variables such as traffic volume to predict more effective PM₁₀ and PM_2.5 distribution grade.

• 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.

• Journal of Korean Society of Forest Science
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• v.81 no.2
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• pp.117-123
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• 1992

In this study, the water soluble sulfur, lead and cadmium contents of Prunus yedoerais leaves were analysed. The water soluble sulfur content considered as a main pollution indicator was extracted by the conventional barium sulfate method and the concentrations were calculated. The results obtained are as follows ; 1. The water soluble sulfur contents of the leaves collected from the heavy traffic roadside trees were two time higher than that of control materials on average. It was presumed those trees has been under meaningful pollutants impact. The water soluble sulfur contents of leaves between Cheonju and Iri was higher than that between Iri and Kunsan. 2. The range of Pb contents from roadside trees was 11.9-34.5 ppm for exceeding the control. The trees grown on the right roadside were more heavliy Pb-contaminated. 3. The range of Cd contents from roadside trees grown between Iri and Kunsan, the site-to-site variations of Cd concentration was not significant.

• Journal of Korean Society for Atmospheric Environment
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• v.26 no.5
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• pp.543-553
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• 2010

Almost five million citizens a day are using subways as a means of traffic communication in the Seoul metropolitan. As the subway system is typically a closed environment, indoor air pollution problems frequently occurs and passengers complain of mal-health impact. Especially $PM_{10}$ is well known as one of the major pollutants in subway indoor environments. The purpose of this study was to compare the indoor air quality in terms of $PM_{10}$ and to quantitatively compare its source contributions in a Seoul subway platform before and after installing platform screen doors (PSD). $PM_{10}$ samples were collected on the J station platform of Subway Line 7 in Seoul metropolitan area from Jun. 12, 2008 to Jan. 12, 2009. The samples collected on membrane filters using $PM_{10}$ mini-volume portable samplers were then analyzed for trace metals and soluble ions. A total of 18 chemical species (Ba, Mn, Cr, Cd, Si, Fe, Ni, Al, Cu, Pb, Ti, $Na^+$, $NH_4^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, and ${SO_4}^{2-}$) were analyzed by using an ICP-AES and an IC after performing proper pre-treatments of each sample filter. Based on the chemical information, positive matrix factorization (PMF) model was applied to identify the source of particulate matters. $PM_{10}$ for the station was characterized by three sources such as ferrous related source, soil and road dust related source, and fine secondary aerosol source. After installing PSD, the average $PM_{10}$ concentration was decreased by 20.5% during the study periods. Especially the contribution of the ferrous related source emitted during train service in a tunnel route was decreased from 59.1% to 43.8% since both platform and tunnel areas were completely blocked by screen doors. However, the contribution of the fine secondary aerosol source emitted from various outside combustion activities was increased from 14.8% to 29.9% presumably due to ill-managed ventilation system and confined platform space.

• Journal of Environmental Science International
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• v.20 no.7
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• pp.799-809
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• 2011

Objectives: This study is aimed at identifying the influential factors on the pulmonary function of ordinary residents in the surrounding areas of Yeosu Industrial Complex. Methods: The PFT (Pulmonary Function Test) was conducted on the target residents numbering 989 people (male 361, female 628). The exposed group (813 people) resided within the radius of 5km from Yeosu Industrial Complex and the control group (176 people) resided in the radius of more than 15 km from May 2007 to November 2007. The survey also took into account other factors including personal characteristics, life habits, respiratory diseases and allergic symptoms, medical histories, and the living environments of the residents in order to further identify influential factors on pulmonary function. Result: When comparing the PFT values of the exposure groups to the control group of the same city, values of the exposure groups were meaningfully lower with an %$FEV_1$ of 107.05% and %FVC of 100.28%. Conversely, the control group reported an %$FEV_1$ and %FVC of 107.26% and 102.85% respectively, indicating that ambient air pollutants reduce lung function. The odds ratio of asthma diagnosis history increased when a subjects residence was close to a heavily trafficked road, traffic amount was huge, a bed was used, and the family had less than four members. However the results were not statistically meaningful. The odds ratios of abnormal pulmonary function were statistically higher among those with asthma(OR=4.29, CI=1.75-10.56), wheezing (OR=2.59, CI=1.24-5.41), and nasal congestion (OR=2.87, CI=1.36-6.08) (p<0.01). The factors affecting $FEV_1$ were symptoms including asthma, passive smoking and allergic eye disease ($R^2$=0.049, p<0.001). For the FVC symptoms including asthma ($R^2$=0.014, p<0.001) were measured. The analysis showed that FVC decreased with increases in $O_3$ and CO(p<0.01). Furthermore, $FEV_1$ decreased with increases in $O_3$(p<0.01). Conclusions: These results will provide preliminary data for establishing responsive measures to protect the health of residents in industrial complexes from air pollution, and to develop lasting environmental health policies.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.5
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• pp.483-492
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• 2020

In this study, we compared and analyzed the Revealed Comparative Advantage (RCA) and Trade Specialization Index (TSI) based on ballast water management systems (BWMS) trade data, which are related to the International Maritime Organization (IMO) Ballast Water Management Convention to suggest the current status of Korea's industrial competitiveness and suggest future development directions for the BWMS industry. As international interest in eco-friendly vessels is expanding, the IMO is engaged in dramatic discussions and agreement-making related to marine emissions of pollutants from ships. IMO member states that must implement this convention are striving to develop technology and secure industrial competitiveness as major industries in the eco-friendly shipping sector, with the BWMS industry experiencing a high market entry barrier and the possibility of the leading market entrants gaining leadership. The Republic of Korea accounts for 17 (approximately 38 %) of the 45 BWMS that received final approval as of October 2019. Based on trade data relating to product codes HS842219, HS84212, and HS89, the RCA index and TSI were calculated and compared. The findings revealed that the Republic of Korea has relative inferiority compared to countries such as Germany and Denmark. Despite this, Korea's favorable industrial environment, which includes several IMO-approved BWMS technologies and the possession of domestic certification institutions, is likely to strengthen its competitiveness in the BWMS market.

• Asian Journal of Atmospheric Environment
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• v.12 no.2
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• pp.109-126
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• 2018

This paper presents seasonal variation of $PM_{10}$ over five urban sites in Sabah, Malaysia for the period of January through December 2012. The variability of $PM_{10}$ along with the diurnal and weekly cycles of CO, $NO_2$, $SO_2$, and $O_3$ at Kota Kinabalu site were also discussed to investigate the possible sources for increased $PM_{10}$ concentration at the site. This work is crucial to understand the behaviour and possible sources of $PM_{10}$ in the urban atmosphere of Sabah region. In Malaysia, many air pollution studies in the past focused in west Peninsular, but very few local studies were dedicated for Sabah region. This work aims to fill the gap by presenting the descriptive statistics on the variability of $PM_{10}$ concentration in the urban atmosphere of Sabah. To further examine its diurnal and weekly cycle pattern, its responses towards the variations of CO, $NO_2$, $SO_2$, and ozone were also investigated. The highest mean value of $PM_{10}$ for the whole study period is seen from Tawau ($35.7{\pm}17.8{\mu}g\;m^{-3}$), while the lowest is from Keningau ($31.9{\pm}18.6{\mu}g\;m^{-3}$). The concentrations of $PM_{10}$ in all cities exhibited seasonal variations with the peak values occurred during the south-west monsoons. The $PM_{10}$ data consistently exhibited strong correlations with traffic related gaseous pollutants ($NO_2$, and CO), except for $SO_2$ and $O_3$. The analysis of diurnal cycles of $PM_{10}$ levels indicated that two peaks were associated during the morning and evening rush hours. The bimodal distribution of $PM_{10}$, CO, and $NO_2$ in the front and at the back of ozone peak is a representation of urban air pollution pattern. In the weekly cycle, higher $PM_{10}$, CO, and $NO_2$ concentrations were observed during the weekday when compared to weekend. The characteristics of $NO_2$ concentration rationed to CO and $SO_2$ suggests that mobile sources is the dominant factor for the air pollution in Kota Kinabalu; particularly during weekdays.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.4
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• pp.409-416
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• 2011

A mobile emission laboratory (MEL) was designed to measure the amount of traffic pollutants with high temporal and spatial resolution under real conditions. Equipment for gas-phase measurements of quantity of CO, NOx, $CO_2$, and THC and for the measurement of the number density and size distribution of fine and ultra-fine particles by a FMPS and a CPC were placed in a mini-van. The exhaust of different type of vehicles can be sampled by MEL. This paper describes the construction and technical details of the MEL and presents data from the experiment in which a car chases city buses fuelled by diesel, CNG, and LPG. The diameters of most particles in the exhaust of the diesel city bus were less than 300 nm and most of the particles had a diameter of 30-60 nm. However, most particles in the exhaust of the CNG and LPG city buses were nanoparticles (diameter: less than 50 nm).

• Journal of Wetlands Research
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• v.22 no.2
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• pp.145-152
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• 2020

Highways are characterized by high non-point pollutant emissions due to high traffic volumes and sections that cause abrupt change in driving speed (i.e. rest stations, ticketing office, etc.). Most highways in Korea were constructed with layers that do not allow adequate infiltration. Moreover, non-point pollution reduction facilities were not commonly installed on domestic highways. This study was conducted to evaluate a facility treating highway runoff and develop a cost-effective design for infiltration facilities by using soil amendment techniques. Performing soil amendment increased the hydraulic retention time (HRT) and infiltration rate in the facility by approximately 30% and 20%, respectively. The facility's efficiency of removing non-point pollutants (Total Suspend Soiled (TSS), Chemical Oxygen Demand(COD), Biological Oxygen Demand(BOD), Total Nitrogen (TN) and Total Phosphorus, (TP) were also increased by 20%. Performing soil amendment on areas with low permeability can increase the infiltration rates by improving the storage volume capacity, HRT, and infiltration area. The application of infiltration facilities on areas with low permeability should comply with the guidelines presented in the Ministry of Environment's Standards for installation of non-point pollution reduction facilities. However, soil amendment may be necessary if the soil infiltration rate is less than 13 mm/hr.