• Asian Journal of Atmospheric Environment
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• v.4 no.1
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• pp.26-32
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• 2010

Concentrations of carbon monoxide (CO) in air were analyzed from seven urban roadside (U-RS) stations in Seoul, Korea over an 11-year period (1998-2008). As noticeable changes in CO levels coincided with the Natural Gas Vehicle Supply (NGVS) program in the year 2000, its concentration data were examined between 1998-2000 (period I) and 2001-2008 (period II). The mean values of CO from all 7 stations for the whole study period were recorded as $1.19{\pm}0.22$ ppm with large drops in its mean from $1.83{\pm}0.43$ ppm in period I to $0.94{\pm}0.21$ ppm in period II. As such, CO levels between the two periods undertook the mean reduction rate of $46.9{\pm}16.2%$ (range of 18.3 to 59.9%). According to the analysis of longterm trends of CO, its concentrations in the U-RS stations decreased very rapidly with the annual mean reduction rate of 9.5% $yr^{-1}$. A line of evidence collected in this study suggests that the implementation of the NGVS program has been quite effective to induce the alterations in CO levels in all urban roadside locations throughout the city of Seoul.

• International Journal of Highway Engineering
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• v.13 no.4
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• pp.9-17
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• 2011

It is possible to set up the Roadside Barrier which is suitable for Performance Evaluation Criteria by domestic standard. But a number of section of expressway roadside have old guardrail that was installed before reform the guideline. These poor performance guardrails threaten driver's life. There is lots of difficult problem to change old guardrails that are installed 2,777km in expressway of whole road side at the same time. Especially budget problem. The purpose of study is to develop performance improvement guardrails by the minimum reinforcement. In this study, guardrail improvement method(SB1, 3, 5 grade) is developed through crash simulation using LS-DYNA 3D and vehicle crash test. And it's expected not only to decrease of collision accident but to increase safe level. Of course one thing that can't be missing is to reduce a lot of budget of guardrail change.

• International Journal of Highway Engineering
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• v.19 no.6
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• pp.1-11
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• 2017

PURPOSES : The purpose of this study is to compare noise reduction quantities between before/after two-layer low noise pavement implementation using equivalent noise level analysis and to analyze the noise reduction effects of the two layer low noise pavement with a statistical method such as the Anderson-Darling Test. METHODS : In order to compare and to analyze noise reduction effects between before/after two-layer low noise pavement implementation, data acquisition as noise levels on a roadside and an apartment rooftop was conducted in the study area. The equivalent noise level was estimated in order to compare noise reduction quantities and the Anderson-Darling Test was carried out for estimating noise reduction effects of the two-layer low noise pavement. RESULTS : The equivalent noise levels of before/after two-layer low noise pavement implementation for the roadside during the daytime are 65.355 dB and 63.520 dB and during the nighttime are 62.463 dB and 59.088 dB. The equivalent noise levels for the apartment rooftop during daytime are 57.301 dB and 59.088 dB and during the nighttime are 54.616 dB and 52.464 dB. Also two-layer low noise pavement decreased the noise reduction effects estimated with the statistical method as the Anderson-Darling test for the roadside during the daytime by around 66.68% and decreased noise reduction effects on the roadside during the nighttime by 0.70%. Moreover it reduced noise reduction effects in the apartment rooftop during the daytime and nighttime by 0% and 96.32%, respectively. CONCLUSIONS : Based on the result of this study, two-layer low noise pavement can positively affect noise reduction during both the daytime and nighttime according to the results of estimating the equivalent noise levels and the Anderson-Darling test.

• The Journal of Natural Sciences
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• v.19 no.1
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• pp.65-75
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• 2008

This research was conducted to determine heavy metal contents of soil and tree in pear orchard located near national road with heavy traffics. Topsoil (0-15 cm depth) and subsoil (15-30 cm) samples in pear orchard located within 40 m from national road had higher Pb, Cu, and Zn contents than background orchard (BG) and these heavy metal contents decreased with distance from road. Topsoil samples taken at 10 m from national road had 4 times higher level in Pb, 3 times in Cu, and 2.5 times in Zn compare to BG. The Cd contents of topsoil in orchard were higher than those of BG but were not in subsoil. Highest heavy metal contents of pear leaves in roadside orchard were 20.08 in Pb, 7.02 in Cu, 30.83 in Zn, and $1.68\;mm.kg^{-1}$ in Cd and these heavy metal contents in roadside orchard were higher than BG. Cd contents of fruit and Pb contents of fruit stalk in roadside orchard were higher than BG and these heavy metal contents decreased with distance up to 40 m from the road.

• Journal of Environmental Science International
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• v.30 no.9
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• pp.727-739
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• 2021

Measurements on mass size distribution of roadside aerosols were obtained in downtown Jeju City from July 2018 to May 2020 using an 8-stage cascade impactor sampler and the compositions of aerosols were analyzed. The mass size distribution of total aerosols was bimodal with aerosols existing in both the fine and coarse modes. The mass size distributions of Na⁺, Mg²⁺, Ca²⁺, Cl^-, NH₄⁺ and SO₄^2- were unimodal, whereas that of K⁺ was bimodal. For NO₃^-, the size distribution in winter and spring was bimodal with the peaks in both fine and coarse modes, whereas for summer and autumn the distribution was unimodal with a peak in the coarse mode. NH₄⁺ was found to co-exist with SO₄^2- in the fine mode with an average molar ratio of [NH₄⁺]/[SO₄^2-] equal to 2.05. Good correlation was observed between NO₃^- and NH₄⁺ in the fine mode particles in spring and winter. Based on the value of the marine enrichment factor for Cl^-, Mg²⁺, K⁺, Ca²⁺ and SO₄^2-, it may be inferred that a major part of the roadside aerosols in downtown Jeju City was largely contributed by terrigenous sources, although the influence of sea salt was normally present.

• Particle and aerosol research
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• v.17 no.1
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• pp.9-20
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• 2021

As a large city advanced, the urban environment is becoming an issue. The contribution of vehicle emissions in air pollutants was very high according to the clean air policy support system (CAPSS). In order to improve the air quality in large cities, it is necessary to establish improvement measures by sources, analyzing the air quality of roadside. We divided Bucheon city into 4 regions to investigate the roadside pollutants of each district using the mobile laboratory (ML) and air quality monitoring station (AQMS). ML was used to measure pollutants emitted from vehicles and AQMS data was used as a comparison group of ML data. As a measurement result of pollutants in the roadside, the concentration of air pollutants in industrial & engineering complex area was the highest and concentration of air pollutants in residential & forest complex area was lower. By street, Bucheon-ro, Sinheung-ro, Sosa-ro, and Gyeongin-ro were identified as high concentrations. Therefore, further researches on preparing management measures for roads in the hot-spot area are needed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.2414-2418
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• 2014

This study carried out three-dimensional finite element analysis and structural safety evaluation of attachable roadside barriers. The effects of diaphragm distance and the number of bolts on displacements and maximum stresses for various parameters are studied using the LS-DYNA finite element program for this study. In this study, the existing finite element analysis of barriers using the LS-DYNA program is further extended to study static behaviors and structural safety of the barrier with module structures connected by anchor bolt inserted through concrete bridge decks. The numerical results for six parameters are verified by comparing different models with displacements and stress distribution occurred in the barrier and shows good structural performance.

• Korean Journal of Environmental Agriculture
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• v.15 no.4
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• pp.494-500
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• 1996

To investigate the relationship between the atmospheric pollution level and the pollution level of soil adjacent to the roadside in Suwon suspended particles and soil samples were collected in August to October 1993, and analyzed by AAS and ICP. The Ca, K, Mg concentration in atmosphere were observed as high level and assumed that it was effected by the acid-rain originated from the erosion of concreate vicinity to the roadside, and the Pb, Zn concentration were higher at outer area than that of central area. Hazardous heavy metal (Cu, Pb, Zn) concentrations in soil were observed as high level at all sampling sites. The relationship between the heavy metal concentrations in the atmosphere and those in the soil were analyzed, by using the correlation coefficient value(r) and the result was appeared similarly. And this study indicated that the atmospheric pollution affect the level of the soil pollution adjacent to the road side.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.4
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• pp.466-477
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• 2007

To understand particle pollution phenomena caused by vehicles, black carbon (BC) concentrations were continuously monitored using an aethalometer at a roadside in Seoul during the period of May 79 to 25, 2005. The BC concentration was highly fluctuated for a short duration, responding to the traffic situation on the road. The lowest BC concentration was observed between 2 and 5 a.m. The local highest BC concentrations were observed during the periods of both morning and evening rush hours. Change in traffic volume accounts for the trend of hourly averaged BC concentrations from the late evening to the morning. Particularly, the slower increase of BC concentration on Sunday seems to respond directly the lower traffic volume in the morning rush hours. From the comparison with a previous work, it is concluded that the BC concentration around midday hours might be dependent on the distance from a road.

• Asian Journal of Atmospheric Environment
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• v.10 no.3
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• pp.137-145
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• 2016

In this study, the contents of dust and associated heavy metals on roadside plants were investigated to assess their foliar transfer. The study was conducted at six different locations (four roadside and two industrial) near an industrial area in Bilaspur (Chhattisgarh), India. Six metals (Fe, Mn, Pb, Cu, Cr, and Cd) were examined in this study. The concentrations of heavy metals in foliar dust were found to be in the order of Fe>Mn>Pb>Cu>Cr>Cd. However, this relative order changed in the case of leaf concentrations to Fe>Mn>Cd>Cu>Pb>Cr. The metal concentrations in the dust and leaves can be attributed mainly to industrial and vehicular emissions. In contrast to other metals, Cd showed significant accumulation in the leaves compared to the respective dust samples. This study showed different patterns in the distributions of heavy metals between the dust deposited on the leaves and the metal accumulated in the leaves. These results suggest that the dust retention and heavy metal accumulation in native plant species should be explored in an attempt to manage these hazardous metallic elements.