• 한국항공운항학회지
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• 제28권4호
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• pp.117-124
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• 2020

This study empirically analyzed air transport trade patterns using data for 30 years between Korea and its trading partners in order to identify specific factors that determine the size of Korea's air transport trade. Independent variables were GDP per capita, capital distance between countries, country area data and number of airports. In addition, it reflected whether it is a landlocked country and whether it has joined the OECD, APEC and ASEAN+3. According to the results of the analysis, it was found that the air cargo trade pattern in Korea is proportional to GDP per capita, and the scale increases as the distance is closer. In addition, the national area and the airport capital acted as a factor in increasing air transport trade. However, whether a country is a landlocked country did not show significant results in terms of trade, exports, and imports. The OECD, APEC, and ASEAN+3 variables were found to generally increase air transport trade.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권2호
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• pp.103-110
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• 2000

In order to understand the wintertime intermittent characteristics of the trans-boundary air pollutant transport observed in East Asia, a numerical simulation of the long-range transport of pollutants was applied using an atmospheric transport model(STEM-II). The numerical simulation was carried out for the entire month of January 1997 and specific atmospheric aerosol (including sulfate, nitrate, and other ion compounds0 observation data were compared from four observation sites(Cheju Island, Kanghwa Island, Dazaifu, and Fukue Island). The observation data revealed that concentration peaks were intermittently observed at 3 to 4-day intervals plus the four observation sites exhibited a very similar spatial variation. The horizontal and spatial scale of the heavily polluted air masses was analyzed based on numerical results. The mechanism of the intermittent transport of air pollutants was clearly explained by a comparison of the observed data with the numerical output. It was found that the wind pattern variations associated with the synoptic scale pressure system changes play an extremely important role in the transport of pollutants in this region.

• 한국농공학회지
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• 제34권E호
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• pp.30-44
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• 1992

A modification of the TEACH-like computer program based on the k-$\varepsilon$ turbulence transport was applied for predicting air mixing patterns and temperature distributions in a rectangular, slot-ventilated enclosure having obstructions ; a rectangular obstacle with heat flux, solid walls separates the passage and the pig pens, and purlins beneath the ceiling. Air flow patterns were calculated for the cases with and without the purlin, extending 300mm beneath the ceiling. Comparisons of prediction data of Randall & Battams(1976) showed air flow pattern predicted well for the case without the purlin. Heat was accumulated at the corner of the left side of the solid wall and the right-upper region of the simulated pigs. However the air distribution pattern was completely different from data for the case with the purlin. The deviation from the observation may be attributed to the difference of the geometric configuation. Exploring the cause of the deviation should be conducted in a further study. Temperature stratification was also observed due to incomplete mixing. The obstruction in the route of the inlet air jet at inlet should be avoided since most of kinetic energy dissipates at the abstacle duet to impingement.

• 한국대기환경학회지
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• 제9권4호
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• pp.329-339
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• 1993

Due to the global-convection currents, transboundary transport of air pollutants is widely observed in many regions of the world. This study was carried out to investigate the pattern of long-range transport of air pollutants in North East Asia, especially the impact of air pollutants originated in China and Japan on the air quality in Korea. From the meteorological data at the 850 mb surface from May 1986 through April 1987 at 54 obsevation stations in the North East Asia region, the backward and forward trajectories were calculated using interpolation method. And the contributions of pollution sources in neighbor countries to the air quality in Korea were analyzed. It was concluded that air pollution in China had a great influence on the air quality in Korea throughout the year : it could be transported to Korea just within 2 or 3 days most of the time. The trajectory analysis showed that pollution sources in Beijing. Liaoning Province, and Shandong Province, the most heavily industrialized areas in China., were the most influential for the air quality in Korea except for summer season. Durnig summer season, the air pollution in Shanhai and Japan could have moer influence on Korea. Such transboundary transport of air pollutants necessitate international cowork and cooperation in the region of North East Asia.

• 한국대기환경학회지
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• 제28권2호
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• pp.142-158
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• 2012

This paper investigates the physical and chemical characteristics of long-range transport (LRT) process of air pollutants by employing the MM5-CMAQ and its comparison with local emission dominant (LED) case over northeast Asia. We first classified high air pollution days into LRT and LED cases based on the synoptic meteorological variables of vorticity and geostrophic wind speed/direction at a geopotential level of over 850hPa. LRT cases are further categorized into three types of transport patterns (LRT-I-III) according to the air mass pathways from source regions. LRT-I-III are originated from northern, central, and southern China, respectively, identified by back trajectory analysis. Three LRT-I-III groups have different and unique locations of high pressure and transport pathways. The chemical characteristics showed that the simulated spatial distributions varied in terms of locations of maximum concentrations and the temporal variation of surface concentrations. The primary air pollutants such as $NO_x$, $PM_{10}$ and $SO_2$ of all of three LRT cases are well transported into Korea peninsula with different concentration levels. Of LRT cases, LRT-II has the greatest effect on air quality of Korea peninsula, followed by LRT-I and LRT-III. In comparison with LRT, the LED case shows relatively higher air pollution concentrations in general, but showed a variety of different air quality levels following the emission strength pattern. These widely varying patterns are impling the case dependent multi-directional approach for the development of indicators of long-range transport process over northeast Asia.

• 한국항행학회논문지
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• 제22권1호
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• pp.13-19
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• 2018

본 논문에서는 저고도 무인기 교통관리 체계에서 운용될 무인기의 사용 용도별로 비행패턴을 분석하였고, 시뮬레이션 모형을 개발하였다. 무인기 비행패턴은 감시형, 선회형, 배송형 패턴으로 분류하였으며, 무인기 사용 용도별로는 농업, 시설 점검, 공공안전 및 보안, 물품 배송으로 총 네 가지 경우를 고려하였다. 또한 저고도 무인기 교통관리 체계에 적용할 공역 운용방식을 검증하기 위한 도구로써 시뮬레이션 모형을 개발하였다. 개발된 시뮬레이션 모형을 감시형 비행패턴에 적용해 보았으며, 그 결과 정해진 입력을 받아 주어진 비행패턴을 그리며 비행하는 것을 확인 및 검증하였다. 본 시뮬레이션 모형은 향후 무인기가 다양한 비행패턴을 그리며 해당 용도에 맞게 안전하고 효율적으로 운항할 수 있는지 검증하는데 사용될 예정이다.

• 한국항공운항학회지
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• 제15권2호
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• pp.32-39
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• 2007

Air Transportation industry becomes more competitive that the restriction on new access to market were eased and relaxed. Liberalization of international air transport will continue, via bilateral and multilateral process. Korea, Japan, and China have expanded enormously the economic trade and cultural exchange bilaterally in the Northeast Asia, they are acknowledging the importance and necessity of improved connection, it order to face effectively other regional blocks of US-Canada, NAFTA, ASEAN, CLMV. In particular, nobody denies that it is urgent to liberalize bilaterally the air transport in Northeast Asia for promoting reciprocal benefits and prosperity. Recently while open skies bilateral agreements was signed between Korea-China in June, 2006. The agreements processes are too heavily influenced by flag carriers; leading to capacity/market sharing between the bilateral carriers in most markets, against the interest of consumers and overall economic interest of the nation. For successful operation of Northeast Air Market, it is need to set up development strategy paradigm by creating cross-border sub-regional (Northeast Asian) open skies bloc as well as preparing and creating of LCCs operations.

• 한국항만경제학회지
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• 제27권1호
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• pp.1-11
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• 2011

글로벌 여객의 해상운송과 항공운송에 대한 수요패턴은 교통수단에 따라 다르게 나타나고 있다. 국제여객선 이용은 1998년 54만 명에서 2008년 253만 명으로 4.7배 증가하였으며, 국제선 항공여객은 1998년 1411만 명에서 2008년 3,534만 명으로 2,124만 명 증가하여 국제선 항공여객보다 여객선에 대한 수요가 더 크게 증가하고 있다. 이에 따라 국제여객 항공운송이 차지하는 비중은 1990년 97.6%에서 2008년 93.3%로 하락하였으나 여전히 대단히 높은 비중을 차지하고 있다. 이러한 점은 국제여객선에 대한 수요를 창출할 수 있는 기회가 그만큼 크다는 것을 의미하는 것이기도 하다. 글로벌 여객은 환율과 경기에 어떠한 형태로든 영향을 받을 수밖에 없기 때문에 본고는 두 운송수단에 대한 수요패턴의 차이를 보이는데 목적을 두었다. 그 결과 환율변동에 대해 항공여객이 여객선여객보다 훨씬 민감한 반응을 보이며 경기상승에 대해 여객선수요가 훨씬 더 크게 나타났다. 경기회복과 더불어 국제여객선에 대한 수요가 크게 증가할 것임을 보여주는 것이다. 환율과 경기충격이 운송에 미치는 효과는 상당히 오랫동안 지속되었다. 항공수요는 경기상승충격에 의한 양의 효과가 환율상승 충격에 의한 음의 효과에 의해 어느 정도 상쇄되는 데 비해, 여객선 수요는 경기충격과 환율충격이 같은 방향으로 작용하여 환율과 경기가 여객선 이용에 대한 수요를 크게 증가시킬 것으로 나타났다.

• 한국대기환경학회지
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• 제20권5호
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• pp.671-683
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• 2004

This study was carried out to understand long-range transport of $SO_2$ using aircraft measurements for the identification of it's horizontal and vertical concentration and distribution pattern. Thirteen missions of aircraft measurements have been done around 37$^{\circ}$00'/124$^{\circ}$30' from October 1997 to November 2001. Concentrations of $SO_2$ was 1.5~2.0 ppb in the below mixing layer, 0.6~1.1 ppb in the above mixing layer. $SO_2$ was found to be relatively higher than marine background level, 0.08~0.2ppb, indicating the western coast being influenced by long-range transport except for the summer season. The vertical distribution of $SO_2$ was classified into 3 groups using its vertical sounding and meteorology pattern; the first is linear decay pattern, the second is exponential decay pattern, and the last is gaussian distribution pattern in the below mixing layer, 2 patterns of linear decay and gaussian distribution patterns in the upper layer. It is founded that vertical distribution pattern is strongly dependent on meteorological condition, for example atmospheric stability and predominant air flow.

• 환경영향평가
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• 제8권1호
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• pp.1-16
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• 1999

The acid deposition and photochemical modeling study was performed on the Eastern Asia using Regional Acid Deposition Model(RADM). The results of this study show that horizontal distribution of $SO_2$, concentration and dry deposition flux was higher in Beking, Shanghai and central part of Korea. However distribution pattern of sulfate and $O_3$ concentration calculated by RADM were not similar to emission pattern. In daytime, $SO_2$, sulfate and $O_3$ were mixed to whole PBL but in nighttime because of inversion layer these pollutants were suppressed to lower level.