• 한국환경과학회지
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• 제22권8호
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• pp.1043-1052
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• 2013

This study was conducted to investigate the correlations between the $PM_{10}$ concentration trend and meteorological elements in the Gimhae region and analyze the transportation routes of air pollutants through back-trajectory analysis. Among the air quality measuring stations in the Gimhae regions, the $PM_{10}$ concentration of the Sambangdong station was higher than that of the Dongsangdong station. Also, an examination of the relationships between $PM_{10}$ concentration and meteorological elements showed that the greater the number of yellow dust occurrence days was and the lower the temperature and precipitation were, the higher the $PM_{10}$ concentration appeared. Furthermore, a cluster analysis through the HYSPLIT model showed that there were 4 clusters of trajectories that flowed into the Gimhae region and most of them originated in China. The meteorological characteristics of the four clusters were analyzed and they were similar to those of the air masses that influence South Korea. These analyses found that meteorological conditions affect the $PM_{10}$ concentration.

• 한국산업보건학회지
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• 제32권2호
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• pp.111-115
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• 2022

Objectives: The purpose of this study is to verify whether droplet-induced propagation, the main route of infectious diseases such as COVID-19, can occur in semiconductor FAB (Fabrication), based on research results on general droplet propagation. Methods: Through data surveys droplet propagation was modeled through simulation and experimental case analysis according to general (without mask) and mask-wearing conditions, and the risk of droplet propagation was inferred by reflecting semiconductor FAB operation conditions (air current, air conditioning system, humidity, filter conditions). Results: Based on the results investigated to predict the possibility of spreading infectious diseases in semiconductor FAB, the total amount of droplet propagation (concentration), propagation distance, and virus life in FAB were inferred by reflecting the management parameter of semiconductor FAB. Conclusions: The total amount(concentration) of droplet propagation in the semiconductor fab is most affected by the presence or absence of wearing a mask and the line air dilution rate has some influence. when worn it spreads within 0.35~1m, and since the humidity is constant the virus can survive in the air for up to 3 hours. as a result the semiconductor fab is judged to be and effective space to block virus propagation due to the special environmental condition of a clean room.

• 한국항공운항학회지
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• 제30권3호
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• pp.19-27
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• 2022

Urban Air Mobility is expected to resolve some problems in urban transportation such as traffic congestion and air pollution. Various studies for a large-scale commercialization of UAM are being actively conducted. To that end, the UAM Traffic Management system aims at securing a safety and an efficiency of UAM operations. In this study, a risk assessment model is proposed to evaluate the risk of collision between a vehicle and surrounding obstacles. The proposed model is conceived from the past studies for determining a proper separation distance between parallel runways for their independent operations. The model calculates the risk that the surveillance system fails to meet a target level of safety for a given buffer zone size between a designed route and surrounding obstacles. The model is applied to one of the routes proposed in K-UAM roadmap to evaluate its performances.

• 한국항공운항학회지
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• 제29권2호
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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.

• 항공우주정책ㆍ법학회지
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• 제20권1호
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• pp.143-209
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• 2005

1994년 북한이 영공개방의사를 밝힌 후, 1996년 대구-평양 비행정보구역 통과 항공로 개설되었다. 2000년 김대중 대통령의 북한 방문 때 서해안 직항로를 이용하는등 남북한의 항공운송협력이 강화되는 듯하였으나, 여러 주변 환경에 대한 운송부담력이 큰 항공운송은 남북한 협력이 쉽게 이루어지지 못하고 있다. 최근 남북한 교류가 증가됨에 따라 경제협력을 논의하기 자리가 자주 마련되고 있으며, 남북한 경제협력사업을 통해 정치적 신뢰성도 증진되었다. 그에 따라 과거에는 불가능하다도 여겨졌던 철도, 도로, 항만의 연계가 실현되었고, 가까운 장래에 남북이 연계된 직항로로 운송이 가능하게 될 것이다. 본 연구에서 남북한 항공운송협력이 갖는 의미는 단순히 남북한의 항공망이 연계 된 것을 의미하는 것을 넘어서 항공운송을 통한 경제협력과 동북아의 허브화를 지향하는 우리의 항공운송산업에 큰 의미를 부여하게 될 것이다. 이는 그 동한 북한이라는 한계에 부딪혀 항공 허브화에 어려움이 있었던 항공운송산업계의 큰 돌파구가 될 것이다. 즉 남북한의 항공연계의 진정한 의미는 동북하의 허브화, 세계적 경쟁력을 갖춘 항공운송산업을 갖춘 한국이 될 수 있는 좋은 기회가 될 것이다. 남북한 항공운송협력을 위한 전략 개발을 위해 환경 분석과 이를 바탕으로 SWOT 분석을 통하여 전략을 개발하였으며, 주변 환경변화에 따라 적절한 전략의 구사가 필요하다. 연구 결과 항공운송협력을 위해 내부 환경과 외부환경의 분석에 나타난 강점, 약점, 위협, 기회 요소들을 적절히 활용하여 단계별 전략의 구사에 활용하는 것이 바람직 할 것이다.

• 한국입자에어로졸학회지
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• 제10권2호
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• pp.61-75
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• 2014

Five on-road measurements were made using a mobile laboratory (ML) to characterize spatial and temporal air pollutant distributions over roads around a day-care center in urban area on 30 August 2013. Fixed monitoring was also done near the day-care center using the ML during the periods between on-road measurements. On-road air pollution monitoring route was classified into seven sections and three zones to identify severe polluted roads among many roads having different traffic volumes and directions. Typical pollutants emitted from vehicles such as $NO_x$, black carbon, particle-bound polycyclic aromatic hydrocarbons, and submicron particles including nanoparticles were monitored using real-time instruments. Peak concentration episodes were frequently observed during the on-road measurements and most peaks were simultaneously monitored at four pollutants. Colored on-road air pollution map for each pollutant provides an insight on spatial air pollution distribution, showing heavily polluted roads and sections. Average on-road $NO_x$ concentration of each run was similar to that monitored at the nearest roadside air monitoring station.

• 대한교통학회지
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• 제35권2호
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• pp.143-159
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• 2017

본 연구는 2003년 1사분기부터 2016년 2사분기 까지 인천국제공항에서 미주노선을 통하여 미주 내 공항에 도착하는 항공화물의 시계열 자료를 통하여 SARIMA 모형을 활용하여 항공화물 수요예측을 시행하였다. 또한 SARIMA 모형을 활용하여 만들어진 수요예측 모형과 기존 연구에 주로 활용되어졌던 ARIMA 모형을 활용하여 만들어진 수요예측 모형과 비교분석함으로써, 주기적인 특성 및 계절성을 가진 시계열 자료에 대한 SARIMA 모형의 상대적으로 우수한 예측 정확성을 입증하였다. 기존의 항공 관련 연구는 주로 여객에 관한 연구가 상대적으로 많았다. 또한 화물과 관련된 연구에서도 특정노선이 아닌 공항이나 전체에 대한 연구가 대부분이었다. 이러한 상황에서, SARIMA 모형을 활용하여 미주지역이라는 특정 노선에 대한 항공화물의 수요를 예측한 본 연구는 큰 의의가 있다고 생각된다.

• 한국연소학회지
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• 제18권4호
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• pp.29-36
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• 2013

Numerical study was conducted to clarify effects of added $CO_2$ for the downstream interaction between $H_2$-air and CO-air premixed flames in counterflow configuration. The reaction mechanism adopted was Davis model which had been known to be well in agreement with reliable experimental data. The results showed that both lean and rich flammable limits were reduced. The most discernible difference between the two with and without having $CO_2$ addition into $H_2$-air and CO-air premixtures was two flammable islands for the former and one island for the latter at high strain flame conditions. Even a small amount of $H_2$, in which $H_2$-air premixed flame cannot be sustained by itself, participates in CO oxidation, thereby altering the CO-oxidation reaction path from the main reaction route $CO+O_2{\rightarrow}CO_2+O$ with a very long chemical time in CO-air flame to the (H, O, OH)-related reaction routes including $CO+OH{\rightarrow}CO_2+H$ with relatively short chemical times. This intrinsic nature alters flame stability maps appreciably. The results also showed that chemical effects of added $CO_2$ suppressed flame stabilization. Particularly this phenomenon was appreciable at flame conditions which lean and rich extinction boundary was merged. The detailed discussion of chemical effects of added $CO_2$ was addressed to the present downstream interaction.

• 한국항행학회논문지
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• 제22권5호
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• pp.367-374
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• 2018

차세대 통신링크를 활용한 항공로 교통 관리를 위해 궤적 기반의 관제 지원 스케줄링 시스템을 제안하였다. 차세대 ATS (air traffic services) 데이터링크인 Baseline 2를 사용하는 4DTRAD (4-dimensional trajectory data link) 서비스 내용을 기반으로 항공로 상을 비행 중인 항공기를 대상으로 하는 궤적기반운용 수행 절차를 수립하고 기술하였다. 이러한 절차를 바탕으로, 다양하고 복잡한 데이터 활용으로 인한 관제사의 업무 부담을 완화하기 위해 지상 시스템이 수신한 항공기 데이터를 처리하여 궤적을 예측하고 관제 조언 정보를 제공하는 스케줄링 시스템의 프로토타입을 개발하였다. 또한, 궤적 기반 항행을 위한 시뮬레이션 환경을 구성하여 개발 시스템에 대한 스케줄링 기능을 확인하였다.

• 한국연소학회지
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• 제20권1호
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• pp.6-14
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• 2015

Numerical study was conducted to clarify effects of added $H_2O$ for the downstream interaction between $H_2$-air and CO-air premixed flames in counterflow configuration. The reaction mechanism adopted was Davis model which had been known to be well in agreement with reliable experimental data. The results showed that both lean and rich flammable limits were reduced in increase of strain rate. The most discernible difference between the two with and without having $H_2O$ and/or $H_2$ addition into $H_2$-air and CO-air premixtures was two flammable islands for the former and one island for the latter at high strain flame conditions. Even a small amount of $H_2$, in which $H_2$-air premixed flame cannot be sustained by itself, participates in CO oxidation, thereby altering the CO-oxidation reaction path from the main reaction route $CO+O_2{\rightarrow}CO_2+O$ with a very long chemical time in CO-air flame to the OH-related reaction routes including $CO+OH{\rightarrow}CO_2+H$ with very short chemical times. This intrinsic nature alters flame stability maps appreciably. The results also showed that chemical effects of added $H_2O$ help lean flames at relatively low strain rate be sustained, and suppress the flame stabilization at high strain rates.