• Title/Summary/Keyword: Air transport

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Assessment of Ventilation System for Ro/Ro Ship Using CFD (전산 유체 해석에 의한 자동차 운반선 내부 환기 시스템 평가)

  • Lee, Sung-Su;Kim, Hak-Sun;Chun, Seung-Hyun
    • Journal of the Society of Naval Architects of Korea
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    • v.42 no.1 s.139
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    • pp.10-17
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    • 2005
  • Due to emission of vehicles during loading/unloading, ventilation system in Roll-on/Roll-off ship is inevitable; however it is very difficult to predict the ventilation performance before it is finally built in. Although the requirements for the ventilation system include air change rate and maximum allowable concentration of CO in the cargo holds, even prototype tests are hardly able to quantify the ventilation performance. In the present paper, a new method to assess the ventilation performance of Roll-on/Roll-off ship is proposed by using computational fluid dynamics. The air exchange is modeled by introducing multi-species transport of existing air In the holds and new air from the ventilation system. Conservation of multi-species as well as 3D Navier-Stokes equation are solved numerically in time dependent manner. Several cases of different configuration are considered. The results include predicted mass fraction of new air in the holds. It is also presented that CO concentration can be estimated based on the predicted air change performance. Due to the lack of experimental data, the computed results are not verified; however the proposed method can be applied as au assessment tool.

A comparative study on the Air Traffic Controller's performance and cognitive imbalance (관제사 수행의 인지적 균형과 불균형의 관계고찰)

  • Shin, H.-Sam
    • The Korean Journal of Air & Space Law and Policy
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    • v.18
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    • pp.105-134
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    • 2003
  • This paper describes generic cognitive aspects of the air traffic controller's performance and perceptive activities unveiled through the past literature study. which underlines mental modelling and mental picture presented in the middle of complicated situational awareness and decision making process when air traffic controller comes to determine the distance between aircraft under control to maintain air traffic in a safe, orderly and expeditious way. It also describes human limit in terms of human memory in conjunction with relative workloads and environmental factor. In conclusion, It suggest that ATC authority will take into account the qualitatiive adjustment of training requirement necessary for ATC facility rating and refresher training to allow them more preparedness for better situational awareness and optimal decision making. In this paper controller's behavioral activators affecting their job performance are addressed in perspective of aviation safety.

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Development of a remote monitoring system for gas detection at the subway station (지하철 역내 가스 검출 원격 모니터링 시스템 구현)

  • Park, Yong-Man;Kim, Hei-Sik;Kim, Gyu-Sik;Lee, Moon-Gyu
    • Proceedings of the KIEE Conference
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    • 2007.04a
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    • pp.439-441
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    • 2007
  • The seoul metropolitan subway has installed 8 lines and about 500 stations to transport 5 million passengers everyday. The underground air pollution level in the subway stations is very severe status, which is very harmful to the commutators and its personals. Although subway roles as such a massive and huge transportation system, the subway doesn't adapt yet any real-time air monitoring system. They have only some hand-held type detector equipments for monitoring air pollution. Therefore subway passengers are exposed to the harmful air pollution environment. The most harmful environmental parameters among the air pollution are known as the dust and sound noise dB level in the subway station. Because the dust is consisted of very small particles, we can't see them easily in dark condition on the platform, but it is very harmful. The monitoring system for air pollution is developed using embedded system attached with 6 different environmental sensors. This system monitors air pollution of dust sound noise, gas, temperature, humidity, inflammable gas, toxic gas in the subway ?station. The sensor unit of the ARM-CPU board and sensor transmits real time environmental data to the main server using Zigbee wireless communication module and TCP/IP network. The main control server receives and displays the real-time environmental data, and it send alarms to the personals when high level value.

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Transport of Ozone in Downwind Area from Seoul Metropolitan (수도권 풍하 지역으로의 오존의 수송에 관한 연구)

  • 이종범;송은영
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.05b
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    • pp.351-352
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    • 2003
  • 오존은 1차 오염물질과는 다르게 광화학 반응에 의한 2차 오염물질이기 때문에 전구물질이 배출되는 지역에서 풍하측으로 수송되어 발생하는 특징이 있다. 따라서 본 연구에서는 수도권 및 강원, 충북의 오존농도자료를 이용하여 대도시에서 풍하지역으로 오존이 수송되는 현상을 분석하고자 한다. (중략)

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