• 한국통신학회논문지
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• 제37B권11호
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• pp.1033-1040
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• 2012

최근 제한된 주파수자원을 효율적으로 활용하기 위해 주파수 공유와 사용 자유화 방안에 대한 연구가 진행되고 있다. 전투요소의 충분한 상호운용성과 실시간 작전속도를 요구하는 네트워크 중심전이 현대전의 중요한 특징으로 부각되고 있는 가운데 무선통신환경에서 제한된 주파수자원의 효과적 관리방안이 군사적으로 연구되고 활용되고 있다. 본 논문에서는 공군 전장 환경에서 효과적 주파수 관리를 위한 주파수 공통상황도 설계를 제안한다. 공군의 주파수 공통상황도를 구축하기 위하여 요구사항을 분석하고 EA(Enterprise Architecture) 프레임워크를 사용하여 주파수 관리 모델을 설계한다. 설계 결과는 공군의 통합방공작전분석모델을 활용하여 그 실효성을 입증한다.

• 한국항행학회논문지
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• 제20권2호
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• pp.141-147
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• 2016

항행안전시설에서 제공되는 항행정보의 서비스를 지속적으로 향상시켜 공항 운영 경쟁력 증진과 항행정보 이용자인 항공기 조종사, 항공교통관제사, 항공사, 및 일반인에게 안정성과 신뢰성 있는 항행정보 서비스 제공이 필요하다. 항행시설 안전성숙도 평가(ASMS; ANSP safety maturity survey)는 항행안전시설 분야의 조직 경영, 안전과 위험관리, 정책 기준 절차관리, 교육훈련 및 근무환경 등 유지관리 및 안전관리 필수요건들이 어느 수준까지 충족하는지를 평가하는 체계이다. 동 평가개발의 추진방침은 국제운영 우수사례 (Eurocontrol, FAA) 등 안전성숙도 평가모델 분석기법을 벤치마킹하여 국내 항행시설 평가체계 분야에 적용하고, 항행시설 유지관리 및 안전도의 계량적인 수준 측정을 위한 핵심 구성요소 발굴을 통해 유지관리(management) 분야의 26개 평가항목 및 안전관리(safety) 분야의 23개 평가항목으로 구성된 평가모델을 개발하였다. 항행시설 안전성숙도평가를 통해 항행안전시설의 성능개선 및 안전사고 예방은 물론 각종 서비스 향상을 유도하여, 이용자에게는 최상의 항행정보를 제공하기 위한 것이다.

• Corrosion Science and Technology
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• 제20권2호
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• pp.94-104
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• 2021

Atmospheric corrosion severity associated with aircraft parking environment was studied using metallic specimens, and temperature and humidity sensors installed at each aircraft operating base. Data were analyzed after a year of exposure. Silver was used to measure chloride deposition by integrating X-ray photoelectron spectroscopy depth profiles. Carbon steel was utilized to determine the corrosion rate by measuring the weight loss. The time of wetness was determined using temperature and humidity sensor data. Analysis of variance followed by Tukey's "honestly significant difference" test indicated that atmospheric environment inside the shelter varied significantly from that of unsheltered parking environment. The corrosion rate of unsheltered area also varies with the roof. Hierarchical clustering analysis of the measured data was used to classify air bases into groups with similar atmospheric corrosion. Bases where aircraft park at a shelter can be grouped together regardless of geographical location. Unsheltered bases located inland can also be grouped together with sheltered bases as long as the aircraft are parked under the roof. Environmental severity index was estimated using collected data and validated using the measured corrosion rate.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.77-82
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• 2005

Recently, people's rising interests toward a 'well-being' lifestyle together with research contributions are accelerating the concerns regarding indoor air pollution making indoor air quality management an emerging environmental challenge of the era. The Ministry of Environment began to regulate the air quality of railway stations last year. The newly established 'Indoor Air Quality Act' covers 17 facilities whereas only underground subway stations and underground markets were regulated by previous 'Underground Air Quality Management Act' of 1996. In this study, we carried out the measurement of temperature, relative humidity, CO(carbon monooxide), $CO_2$(carbon dioxide), HCHO(formaldehyde), PM-10(particulate matters), and VOCs(volatile organic compounds) in underground subway stations. Based on the obtained results, we will suggest a way to improve the indoor air quality of the subway stations.

• 한국대기환경학회지
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• 제33권4호
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• pp.403-410
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• 2017

With the growing importance of GHG reduction, wood pellets are considered as a cheaper renewable energy and carbon neutral. On the other hand, there is a concern that the burning wood pellets may release even more air pollutants such as CO and VOCs. In this study, we analyzed the social costs of burning fuels including wood pellets and coals based on the unit calorific value. The social costs were calculated by sum of the import costs of the fuels and the emission costs of the air pollutants. The results showed that wood pellets are inferior to coals in the aspect of the social costs. It is necessary to improve the quality of the wood pellets and pellet boiler facilities for being used eco-friendly energy sources in the future. We suggest that the control facilities of CO and VOCs should be installed, if the control costs are lower than the pollution costs.

• 대한안전경영과학회지
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• 제13권3호
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• pp.199-208
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• 2011

Environment standards can be used as a foundation of environment administration (specific expression of political goals or quantitative evaluation standards of political effects). When environment adminstration improves severe air or water pollution rapidly, the environment standard can work effectively to show the goals specifically and clearly. The environment index which is designed to evaluate environment systems, should be established to express the environment system generally. To realize sustainable development, the sustainable indexes usually consisting of these three areas in that harmony of environment, economy and society are required. In this research, sustainable environmental indicators to understand the characteristics and to compare likes theme of environmental conditions in international and national level indicators, regional environmental management plan to promote the management by objectives are to provide the basic data. It is desirable for the environmental policies to work harmoniously with direct control, use of economic means and voluntary methods. Regarding the evaluation of environmental index, the action results of civilian's or individual's activities are needed to be reflected into the evaluation.

• 한국항공운항학회지
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• 제30권4호
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• pp.1-8
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• 2022

In this study, we propose trajectory-based arrival management using CDO (Continuos Descent Operations). The operational procedures with TBO (Trajectory-Based Operations) concept were established to allow aircraft and ground system to share the trajectories with each other in real time. The proposed operational concept was validated in the air traffic control simulation environment, which consists of controller working position, pseudo pilot system, air traffic generation system, and controllers' decision support system for arrival management using CDO. Simulation results compared with actual flight data indicate that proposed concept could improve the efficiency of traffic flow management in terms of total descending time and fuel consumption. And it was confirmed that if there is a system that can share and utilize the synchronized trajectory, it can be helpful to control arrival aircraft and apply CDO concept.

• 환경위생공학
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• 제7권2호
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• pp.69-82
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• 1992

Air pollution in urban areas of Korea is considered in significantly serious level because of population exceeding the capacity and diversified facilities for the activities in socioeconomic field, education, politics and even cultural society in confined areas. Korea is one of the most populated countries and the largest five cities occupy 2.4% of total area but 45% of total population. Patterns of urban air pollution are also changing due to the change of emission sources and fuel usage. Essential recovery of urban environment in Korea has become extremely difficult and necessitates enormous investment. Accurate understanding of problems should be pursued for the efficient and effective improvement of the environment. In this article, air pollution phenomena in urban areas are analyzed mainly with respect to recent urban air pollution trend and pollution sources and possible control strategies are discussed : 1) source control-stationary and mobile, 2) air quality management strategies, 3) research and development.

• 한국환경생태학회지
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• 제33권3호
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• pp.366-374
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• 2019

본 연구는 폭염 및 미세먼지 저감을 위한 계획요소인 바람길의 활용 가능성을 논의해보고자, 전주시를 대상으로 바람길의 특성을 분석하고, 바람길 활용을 위한 방안을 제안하는 것을 목적으로 한다. 이를 위해, 호남정맥에 위치하는 전주지역 일대의 찬공기 흐름 및 찬공기 층 높이 등 찬공기 특성을 분석하였고, 전주시의 주요한 바람길을 특정하였다. 또한, 이를 바탕으로 전주시 일대의 산림관리 및 도시계획 활용방안을 제안하였다. 찬공기 특성 분석을 위해 독일에서 개발된 모형인 KALM(Kaltluftabflussmodell)을 이용하여 야간 6시간 동안 생성되는 찬공기 흐름 및 찬공기층 높이를 파악하였다. 분석 결과, 시간이 경과함에 따라 전주시 외곽 북동쪽 및 동쪽에 위치한 산림에서 생성된 찬공기의 흐름이 뚜렷해지고, 계곡지역과 농경지 일대에서 찬공기층의 높이가 증가하였다. 특히, 전주시의 찬공기 흐름은 북동쪽과 동쪽에서 생성된 찬공기가 전주시 중심 시가지로 유입되어 남쪽으로 흘러나가는 형태를 가지고 있어, 이상적인 바람길의 구조를 보여주는 사례였다. 찬공기 분석 결과를 바탕으로, 찬공기 생성이 활발한 산림지역 일대를 '찬공기 보전지역'으로 지정하고, 원활한 찬공기 흐름을 위해 관리가 필요한 지역을 '찬공기 관리지역'으로 지정하여, 찬공기 흐름을 유지 및 확대할 수 있는 방안을 제안하였다. 본 연구의 결과는 전주시의 기후변화 적응 정책, 바람길숲 조성 사업 등 폭염과 미세먼지 해결을 위한 정책 수립과 연구의 기초자료로 활용될 수 있을 것으로 기대한다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.163-166
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• 2002

The concurrent injection of cosolvent and air, a cosolvent-air (CA) flood was recently suggested for a dense nonaqueous phase liquid (DNAPL) remediation technology. The objectives of this study were to elucidate the DNAPL removal mechanisms of the CA flood and to quantify mass transfer rate coefficients during CA flooding. DNAPL removal mechanisms were examined by evaluating the effects of air flow rate and DNAPL solubility and visually documented at a pore-scale. Two serial processes, immiscible displacement and dissolution, were experimentally and visually documented during CA flooding. Mass transfer rate coefficients (K) were computed from the data showing PCE saturation versus time. Results showed that CA floods exhibited higher K values than cosolvent floods without concurrent air injection. (This document has not been subjected to Agency review and therefore does not necessarily reflect the views of the Agency, and no official endorsement should be inferred.)