• Atmosphere
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• v.33 no.4
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• pp.343-354
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• 2023

Turbulence produced on roadways is one of the major factors determining the dilution rates at the initial stage of traffic emissions of air pollutants and, thus, the distribution of air pollutants near the roadways. Field experiments were conducted on Gyeongbu Highway, one of the busiest highways in Korea, for 4~7 days in winter, spring, and summer. Two three-dimensional ultrasonic anemometers were installed on both sides of the highway to estimate turbulence intensities (vertical wind fluctuation and kinetic turbulence energy) induced by the roadway. Roadway-induced turbulence consists of three components: structural road-induced turbulence (S-RIT), thermal road-induced turbulence (T-RIT), and vehicle-induced turbulence (VIT). The contribution of T-RIT to the total RIT was insignificant (less than 10%), and the majority of RIT was S-RIT (by the highway embankment) and VIT. In this study, we propose the empirical relationships of VIT as a function of traffic density and wind speed under free-flow traffic conditions. Although this empirical relationship appears to underestimate the VIT, it can be applied to the air quality models easily because the relationship is simple and only needs readily obtainable input variables (wind speed and traffic information).

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.1
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• pp.97-116
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• 2011

This study analyzed indoor air pollutants from elementary school with different environment. Air sampling and measurement were carried out from classrooms and hallways from three target elementary schools in the fall and winter seasons. The winter average concentrations of $PM_{10}$, $CO_2$, CO, aldehydes and ketones, and benzene were higher than the fall ones. The fall average concentrations of $O_3$ and $NO_2$ were higher than the winter ones. The concentrations of $PM_{10}$ and $CO_2$ at the schools near the heavy traffic areas and having poor ventilation were higher than those from the other elementary school. The average concentration of CO at the school having heavy traffic volume was highest. The concentrations of $O_3$, $NO_2$, aldehydes and ketones, and VOCs at the school near the shipbuilding industries were highest among the three elementary schools.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.29 no.2
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• pp.55-66
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• 2021

ICAO recommended that airspace monitoring and periodic safety assessments in each Contracting State ensure the stability of the airspace, since reducing the aircraft lateral and vertical separation intervals would rather increase the risk of collision. The target level of safety of the AKARA-FUKUE Corridor at the southern end of Jeju was 247×10^-9. In simple comparison, this means that the risk of an aircraft collision in this area (international safety standards, 5.0×10^-9) is about 50 times higher. The scope of this study is to organize the concept of terms, analyze the air traffic volume, the current status of navigational safety facility usage fees, and investigations of an aircraft collision risk in Jeju southern air corridor. Analyzing government policies and overseas evaluations, revising some of the existing contents, presenting some of the additional contents of new routes, and changing the instrument procedure for Korean-Chinese routes, change of arrive/departure route between Incheon Airport and Shanghai Airport, reduce the risk of aircraft collisions. We hope to restore airspace sovereignty, contribute to policies for the government to take the lead in solving this problem, and expect stability and operational efficiency in air traffic.

• 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.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.19 no.3
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• pp.43-53
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• 2011

It is well known some Foreign aircraft used to fly INCHEON FIR(Flight Information Region), especially the island of IEODO without a flight plan, even though foreign aircraft is subject to submitting a flight plan to Flight Information Center(FIC) before its flight. IEODO is a sunken rock 4.6m beneath the sea level, 149km away from Marado. Facing the Yangtze river's sea entrance horizontally and military zones of Korea and China vertically, IEODO is a very important place for national security of North East Asia because it is located at the boundary between China East Sea and Yellow Sea of South Korea. Moreover, JDZ(the 7th mine lot) is just 77NM from IEODO, which possesses natural gas eight times bigger than the gulf region and oil 4.5 times bigger than that of the U.S. In addition, INCHEON FIR, managed by MLTM(Air Traffic Control Center) and Japanese Self-Defense Force's JADIZ(Japanese Air Defense Identification Zone) are overlapping on IEODO whose air space is very complex. This paper focuses on air space, FIR, ADIZ(Air Defense Identification Zone) and related airspace system and suggests strategic implications of how to prevent foreign aircraft from invading INCHEON FIR without permission and of how to utilize the airspace efficiently.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.4
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• pp.378-386
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• 2014

The use of bus stop in the center lane has reduced the emissions of exhaust gas on the road due to the improvement of the traffic speed but has caused a health problem for the citizens who are waiting for the bus in the platform, and thus the air pollution control of bus stop in the center lane is emerging as a more important part. This study was conducted to investigate the air pollution degree for the center lane-bus stops in four regions using mobile air measuring vehicle, and to evaluate the characteristics of air pollution by comparing with the data measured at the urban air monitoring site close to the bus stops. In addition, the correlation analysis was performed to analyze the impact to neighboring region by vehicle exhaust gas. The regional mean concentration of nitrogen dioxide in the center lane-bus stops ranged from 0.025 to 0.043 ppm which shows from 2.5 times to 5.3 times higher than the values of urban air monitoring site selected as a control group. The regional mean concentration of ozone in the center lane-bus stops ranged from 0.023 to 0.034 ppm which shows from 3% to 28% lower than the values of urban air monitoring site selected as a control group. The concentrations of nitrogen dioxide and ozone for the sampling regions did not exceed one hour-air quality environmental standard (0.1 ppm). The mean concentration of particulate matter for four center lane-bus stops was $28{\mu}g/m^3$ which shows about 27% higher than the values of urban air monitoring site selected as a control group, and that of particulate matter did not exceed one day-air quality environmental standard ($100{\mu}g/m^3$). In the results of correlation analysis between data from center lane-bus stops and data from urban air monitoring sites, the correlation coefficient (r) of nitrogen dioxide was relatively low as 0.316 to 0.416, and the correlation coefficient was high as the distance was close and vice versa. However, the correlation coefficient of ozone ranged from 0.167 to 0.658 and the correlation coefficient was high as the distance was far and vice versa.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.153-155
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• 2006

A major advantage of the area in and around Braunschweig is its concentration of major research institutes and small to large enterprises dealing with different modes of transportation. For many years, aviation has been a particular focus. The research institutes have aircraft and helicopters equipped especially for research projects, as well as other laboratory equipment, allowing simulation and testing of air traffic application both virtually and on real aircraft. In addition, with the Luftfahrtbundesamt (equivalent organization to FAA) and the Bundesstelle $f{\"{u}}r$ Flugunfalluntersuchung (equivalent to NTSB) both located at the Research Airport, it enables direct contact with two key air-traffic safety authorities. The institutes of DLR and the Technical University of Braunschweig are very active in rail transportation applications. Cooperation with the market leader in rail automation - Siemens Rail Automation, also located in Braunschweig - and with other companies in the Braunschweig region means that safety-critical road applications and mobility research is available due to the activities of a number of institutes. Cooperation with Volkswagen (VW) and other companies in the region ensure access to the market leaders' know-how in this sector. Current European activities within framework of the Galileo project offer particularly good opportunities for the Research Airport to leverage its expertise and position itself internationally as a specialist in safety-critical transport applications - the centre is an initiative of Niedersachsen and the Ministry of Economic Affairs, Labour and Transport Location and navigation plays a central role in all modes of transport - air, road and rail. The market is being revolutionized by the increasing integration of GNSS. The realization of the Galileo system will provide additional opportunities for the Research Airport: Galileo as a civil operated system offers service guarantees especially in the area of safety-critical applications in transportation. Notably standards, processes and authorizations related to the certification of safety-critical applications in the areas of air, road and rail transportation are still to be determined. GAUSS, located at the Research Airport Braunschweig, as an European centre of excellence for simulation, testing and certification of safety-critical applications can offer its expertise to validate the services guaranteed by the Galileo concessionaire.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1238-1243
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• 2009

As Social Overhead Capital(SOC) has been expanded, the highway road construction has been accelerated and city road system has been more complicated. So, long road tunnels have been increased and traffic flow rate also has been raised. Accordingly, the exhausting gas of vehicle cars seriously deteriorates the tunnel inside air quality and driving view. In order to improve tunnel inside air quality, it is needed to introduce a compulsory ventilation system as well as natural ventilation mechanism. The former, that is, a special compulsory ventilation facility is very useful and helpful to prevent a tunnel of being contaminated by traffic in most case. In the case of obtaining clearer and longer driving view, the ventilation systems have to be considered in order to remove floating contaminants or exhaust gas from engines. In this paper, discharge electrode design technology will be discussed.

• Asian Journal of Atmospheric Environment
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• v.12 no.3
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• pp.204-214
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• 2018

Indoor air quality was investigated in homes and daycares located in areas with heavy traffic in Seoul, South Korea from November 2013 to January 2014. Indoor and outdoor air quality measurements were collected for 48 hours in four children's homes and daycare centers. The I/O ratio (Indoor to outdoor ratio) for each major air pollutant ($NO_2$, black carbon, $PM_{10}$, and $PM_{2.5}$) was calculated, and $NO_2$ and $PM_{10}$ concentration profiles were analyzed based on indoor activity diaries recorded during the 48 hours. Most I/O ratios for $NO_2$, black carbon, $PM_{10}$, and $PM_{2.5}$ at daycare centers were less than one. At homes, I/O ratios for black carbon, $PM_{10}$, and $PM_{2.5}$ were less than one; however, most I/O ratios for $NO_2$ were greater than one due to the usage of gas stoves. The children's exposure to indoor air pollutants was calculated using a time-weighted average exposure method, and the daily intake level for each pollutant was determined.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.5
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• pp.506-517
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• 2012

Electronic Toll Collection System (ETCS), so called "Hi-Pass" in Korea, has improved traffic flow at toll gate of highways. It is known that the improvement of traffic flow should reduce air pollutants and $CO_2$ from vehicles. In this study, real driving emission of a light duty truck with Portable Emission Measurement System(PEMS) has been measured to evaluate the emission reduction effect due to ETCS. The correlations between driving variables and emissions have been analyzed to verify its effect on traffic flow improvement and emission reduction at toll gate. We considered average vehicle speed, Relative Positive Acceleration (RPA), and the distance of queue as driving variables. Compared to passing Manual Toll Collection System (MTCS) lane without queue, ETCS was able to reduce 38.7% of $NO_x$, 21.6% of soot, and 27.7% of $CO_2$. The results showed that the higher the average vehicle speed, the lower RPA and no queue in ETCS contributed to the emission reductions. Linear equation models with RPA and queue have been established by the multiple linear regression method. The linear models resulted in the higher coefficient of determination than those with only average vehicle speed used for establishing vehicle emission factors.