• Journal of the Korean Society for Aviation and Aeronautics
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• v.14 no.4
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• pp.66-73
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• 2006

This study focuses on the economies of launching regular air services between capital cities of South Korea and North Korea. The demand for traveling between these two cities is too small to justify scheduled air service. However, it may be possible to provide regular air service by utilizing via flight of incumbent Seoul-Beijing flights. There are numerous flight services between Seoul and Beijing and we may allow some of the Seoul-Beijing flights to stop by Pyung Yang for commercial traffic handling. This study tries to find the optimal discount rate which passengers traveling between Seoul and Beijing via Pyung Yang, the idea is reasonable considering the inconvenience of stopping at Pyung Yang. The Stated Preference Techniques are applied for the study. The required data were collected through interviews of passengers traveling from Seoul to Beijing. The major variables that are considered in flight choice are air fare, flying time, and flight frequency. The relative importance of these major variables is estimated by the logit models calibrated with stated preference data.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.541-545
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• 2008

Particulate matter (PM) is one of the major indoor air pollutants especially in the subway station in Korea. In order to remove PM in the subway station, several kinds of PM removal system such as roll-filter, auto-washable air filter, demister, and electrostatic precipitator re used in the air handling unit (AHU) of subway station. However, those systems are faced to operation and maintenance problems since the filter-regeneration unit consisting of electrical or water jet parts is malfunctioned due to the high load of particulates and the filter material needs periodic replacement. In this study, we surveyed the particle removal systems in order to develop the new system of particle removing can be adopted in the current AHU of subway station.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.4
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• pp.298-304
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• 2021

This study aimed to determine the applicability of drones and air quality sensors in environmental monitoring of air pollutant emissions by developing and testing two new methods. The first method used orthoimagery for precise monitoring of pollutant-emitting facilities. The second method used atmospheric sensors for monitoring air pollutants in emissions. Results showed that ground sample distance could be established within 5 cm during the creation of orthoimagery for monitoring emissions, which allowed for detailed examination of facilities with naked eyes. For air quality monitoring, drones were flown on a fixed course and measured the air quality in point units, thus enabling mapping of air quality through spatial analysis. Sensors that could measure various substances were used during this process. Data on particulate matter were compared with data from the National Air Pollution Measurement Network to determine its future potential to leverage. However, technical development and applications for environmental monitoring of pollution-emitting facilities are still in their early stages. They could be limited by meteorological conditions and sensitivity of the sensor technology. This research is expected to provide guidelines for environmental monitoring of pollutant-emitting facilities using drones.

• The Korean Journal of Air & Space Law and Policy
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• v.9
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• pp.183-197
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• 1997

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.21 no.2
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• pp.100-104
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• 1992

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.17 no.4
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• pp.288-290
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• 1988

• Journal of the Korean Society for Aviation and Aeronautics
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• v.9 no.1
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• pp.31-44
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• 2001

This paper addresses legislation status of air route design standard of Korea. Korea Ministry of Construction and Transportation's Order Number 300 (March 28, 2001) prescribes that firstly, the design of air routes in Korea should be in accord with International Civil Aviation Organization(ICAO)'s recommendations published in Annex 11: Air Traffic Service and Procedures for Air Navigation Services: Aircraft Operations (ICAO Doc 8168-OPS, 1986), and secondly, United States Federal Aviation Administration(FAA)'s Terminal Instrument Procedures (FAA, 1976). An investigation on the current air route specifications of Korea reveals that they are in accord with neither ICAO's recommendations nor FAA's standards in that the width of Korea's air routes are narrower that the international recommendations and standards. As a member state of ICAO, it is imperative for Korea to follow the international standards. In that purposes, Korea should legislate and regulate the detail standard for air route design. For the legislation, FAA regulations are to be followed because FAA rules contains more detail specifications while ICAO recommendations includes allows a range of policy decisions, which may result in a confusion in practice.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.11
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• pp.570-579
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• 2017

In this study, we examined the multi-stage piston-type air compressors typically used in a railroad vehicle, and the heat transfer efficiency was analyzed according to the design conditions of the heat exchanger (a compressor component module for cooling the compressed high temperature air). For the fin-tube heat exchanger used in the most air compressors, numerical analysis was performed to analyze heat transfer by defining the various rectangle tube sizes and the number of fin-per-unit area as design variables under the same flow rate of compressed air. Also, this analysis compared the temperature of the compressed air. Regarding environmental conditions for analysis, the flow rate of the external cooling air was measured and the mean value of the values was applied. And a "turbulence model" was considered in both the external flow of the cooling air and the internal flow inside the tube. From the results of analysis, it was found that the change of the aspect ratio value of the tube greatly influences the heat transfer efficiency of the compressed air, and influences if the fin density is relatively small. As a result, the optimum design specifications of the heat exchanger for air compressors were confirmed based on the analysis of the heat transfer efficiency, according to the design conditions of fin and tube by the operating temperature range of the compressed air.

• Journal of the Korea Institute of Military Science and Technology
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• v.24 no.6
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• pp.664-675
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• 2021

Air force air-to-air combat tactics are occurring at a high speed in three-dimensional space. The specification of the tactics requires dealing with a quite amount of information, which makes it a challenge to accurately describe the maneuvering procedure of the tactics. The specification of air-to-air tactics using natural languages is not suitable because of the intrinsic ambiguity of natural languages. Therefore, this paper proposes an approach of using UML Sequence Diagram to describe air-to-air combat tactics. Since the current Sequence Diagram notation is not sufficient to express all aspects of the tactics, we extend the syntax of the Sequence Diagram to accommodate the required features of air-to-air combat tactics. We evaluate the applicability of the extended Sequence Diagram to air-to-air combat tactics using a case example, that is the manned-unmanned teaming combat tactic. The result shows that Sequence Diagram specification is more advantageous than natural language specification in terms of readability, conciseness, and accuracy. However, the expressiveness of the Sequence Diagram is evaluated to be less powerful than natural language, requiring further study to address this issue.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.4
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• pp.353-368
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• 2013

All Koreans had suffered heavily from municipal and industrial air pollution problems since 1960's to 1980's. However the levels of $SO_2$, CO, and Pb have been dramatically decreased since 1990's due to various air pollutants' reduction policies under the provisions of the 1978 Environmental Preservation Act and the 1990 Air Quality Preservation Act such as increasing the supply of low-sulfur fuel, the use of cleaner fuel, no use of solid fuel, and so on. Even though the national ambient air quality standard has been strengthened to protect public health and welfare, the levels of $NO_2$, $O_3$, and $PM_{10}$ frequently exceed the corresponding standards; for example, only 4 stations (1.7%) out of 239 nationwide monitoring stations satisfied the 24-hr based PM10 standard in 2011. Moreover, upto the present time, since there are serious underlying policies of economism and growth-first which can not be solely solved by the environmental laws, it is difficult to root out undesirable social evils such as public indifference, passive academic activities, complacent government bureaucracy, insufficient social responsibility of enterprise, and radical activities of environmental groups. The paper initially reviewed air pollution history of Korea with surveying various environmental factors affecting in/out-door air pollution in the past Korea. Further this study extensively investigated legal and political changes on air pollution control and management for the last 50 years, and then intensively discussed the present environment-related laws and policies unreasonably enforced in Korea. It is necessary to practically revise many outdated legal policies based on health-oriented thinking and on our current economic levels as well.