• Title/Summary/Keyword: 환경 풍동

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Study on characteristic of variation wind profile at surface using wind tunnel (풍동을 이용한 지표 바람장 변화 특성에 관한 연구)

  • Jang, Mi;Kim, Jung-Won;Kim, Sin-Do
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.05b
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    • pp.358-361
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    • 2003
  • 우리의 생활 주변에는 자연적으로 배출되는 오염물질과 인간의 사회활동을 통해서 발생하는 인위적인 오염물질이 있다. 배출원에서 발생하는 오염물질은 배출조건이나 주변지역의 장애물, 또는 기상조건 등과 같은 많은 변수들 때문에 오염물질의 확산에 많은 영향을 받는다. 따라서 실제 대기 중의 복잡한 확산특성을 이해하기 위해서는 바람특성에 대한 보다 정확한 정보가 필요하다. 이러한 확산조건을 정확히 파악하기 위해서는 현장에서 장기간의 시간을 가지고 실측 데이터를 얻는 것이 가장 좋으나 이는 경제적 또는 실험적인 한계로 인해 불가능하다. (중략)

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Effects of $CO_2$ concentration and air current speed on the growth and development of plug seedlings under artificial lighting (인공광하에서 플러그묘의 생육에 미치는 $CO_2$ 농도와 기류속도의 영향)

  • 김용현
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1999.04a
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    • pp.54-57
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    • 1999
  • 플러그묘의 생육과 밀접한 관계를 갖는 플러그묘 개체군(이하 '묘개체군'이라 칭함) 내외에서의 미기상 요소는 기류속도의 영향을 크게 받는다. 식물묘공장과 같이 인공광을 이용한 반폐쇄 생태계에서 품질이 균일한 플러그묘 생산 시스템 개발을 목적으로 수행된 기초 연구에서 김과 고재(1996a, 1996b, 1996c, 1997), Kim 등(1996)은 플러그묘 생산용 풍동 설계 및 공기역학적 특성의 구명, 기류속도가 묘개체군 내외에서 기온ㆍ상대습도ㆍ포차ㆍ$CO_2$ 농도 분포에 미치는 영향, 묘개체군의 순광합성 속도 측정 등에 관한 연구 결과를 보고한 바 있다.(중략)

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Wind-Tunnel Simulation on the Wind Fence Effect (방풍망 효과에 대한 풍동 시뮬레이션)

  • Kang, Kun
    • Journal of Environmental Science International
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    • v.7 no.1
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    • pp.20-26
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    • 1998
  • In establishing artificial fences in a certain locality, type of its area or wind blown against them from the front side is primarily considered. Researchers on fences also concentrate on upstream, wand blown against them from the front side In 90$^{\circ}$ angle. In this research, simulations were carried out on the direction of wind changed by each season, and regardless of seasonal wind, on the fences effect of wind direction on fences, throu호 an atmospheric boondary layer wind tunnel. When I compared the velocity distribution of upstream against the fences in 90$^{\circ}$ angle with that of 75$^{\circ}$, 60$^{\circ}$, and 45$^{\circ}$ respectively, the velocity distribution at downstream of the latter cases generally surpassed that of the former one.

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Wind Tunnel Experiments for Studying Atmospheric Dispersion in the Complex Terrain I.Dispersion in a mountainous Area (복잡한 지형내 오염물질의 대기확산 풍동실험: I. 산지지형에서의 확산)

  • 경남호;김영성;손재익
    • Journal of Korean Society for Atmospheric Environment
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    • v.8 no.3
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    • pp.169-178
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    • 1992
  • Dispersion of pollutant in a mountainous area is simulated in a wind tunnel. In the northwest side of the terrain model, the sea level is assumed. Wind from the sea initially confronts hills along the shoreline, a line of large buildings next, and finally a valley between high mountains in the south and in the east. In the northwest wind conditions, severe flow separation occurs in the lee side of hills, even beyond the building area. Pollutant from the buildings is trapped in this region and its concentration is the highest. In the west wind conditions, pollutant from the buildings flows along the hills aslant the main wind direction in this case. Since large valley is located in the downstream, pollutant tends to disperse along the valley.

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Design Guidelines of Elevated Buildings for Antarctic Environment (I)-Wind Load (남극환경을 위한 고상식 건물의 Design Guideline에 관한 연구(I)-풍하중)

  • Kim, D. H.;Kwon, K.C.S.;Rohde H.F.
    • Journal of Ocean Engineering and Technology
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    • v.4 no.2
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    • pp.22-34
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    • 1990
  • 남극환경은 남극의 거센 바람 및 이에 수반되는 적설현상을 피하기 위해 땅에서 띄우는 고상식 및 지하에 설치하는, 두가지의 형태를 취하고 있다. 고상식의 경우 건물밑으로 바람을 통하게 함으로써 적설현상을 피하는데 효과적이기는 하나 남극의 거센 바람에 대응하기 위하여 구조적인 문제를 해결해야 하는 취약점을 지니고 있다. 본 연구는 경계층난류풍하를 이용하여 고상식 남극건물에 가해지는 풍하중을 파악함으로서 남극건물의 design guide line을 제시하였다.

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Effects of air current speed on the growth of plug seedlings under artificial light (기류속도가 인공광하의 플러그묘 생장에 미치는 영향)

  • 김용현
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1997.05a
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    • pp.74-79
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    • 1997
  • 플러그묘의 생육과 밀접한 관계를 갖는 플러그묘 개체군(이하 '묘개체군' 이라 칭함) 내외에서의 미기상 요소는 기류속도의 영향을 크게 받는다. 인공광을 이용한 반폐쇄생태계에서 품질이 균일한 플러그묘 생산 시스템 개발을 목적으로 실험을 수행한 금과 고재$^{(1)~(4)}$ , Kim등$^{(5)}$ 은 최근들어 플러그묘 생산용 풍동 설계 및 공기역학적 특성의 구명, 기류속도가 묘개체군내외에서 기온ㆍ상대습도ㆍ포차ㆍ$CO_2$ 농도의 분포에 미치는 영향, 묘개체군의 순광합성 속도 측정 등에 관한 연구 결과를 보고한 바 있다. (중략)

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Wind Tunnel Experiments for Studying Atmospheric Dispersion in the Complex Terrain II. Gaussian Modeling of Experiments in a Moutainous Area (복잡한 지형내 오염물질의 대기확산 풍동실험 I I. 산지지형 실험의 Gaussian 모델링)

  • 김영성;경남호
    • Journal of Korean Society for Atmospheric Environment
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    • v.11 no.2
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    • pp.145-152
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    • 1995
  • Predictability of a Gaussian model, ISCST2 was assessed by scaling up wind tunnel experiments with a 1/3,000 terrain model to the real scale. Concentration profiles obtained from the flat-terrain experiment in the neutral condition were estimated to be in agreement with the calculated ones from ISCST2 in the stability class A, but the difference between the two was still large. Concentration profiles from the mountainous-terrain experiments were better fitted to the calculated ones primarily because in the experiment, concentration behind the source was raised due to the effect of a hill in the upstream side. Model prediction was improved with including the downwash effect of buildings and the hill, but overall concentration profiles were not much different from a typical Gaussian profile. While concentration profiles in the experiments were changed with local flows by varying the wind direction and the topography, those from the Gaussian modeling were mot freely changed together with these variations.

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Wind-Tunnel Simulation of Windbreaks to Control Windblown Dusts in the Atmospheric Boundary layer (대기 경계층내에서 바람에 의해 발생되는 부유 물질 제어를 위한 Windbreaks의 풍동 시뮬레이션)

  • Kang, Kun
    • Journal of Environmental Science International
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    • v.4 no.1
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    • pp.29-40
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    • 1995
  • Transport rate of windblown dusts such as soil, sand, snow is proportionate to $U*_^3 and U_*$, friction velocity, approximately to flow velocity of ink Therefore, through measurement and the flow velocity of wind, it turned out that, considering different velocity distributions caused by downstream distance and porosity percent, windbreaks with appropriate porosity rate to the Protection area should be chosen for the optimal fence effect. In the economic respects better are fences with gap of 20%~30%. Among the windbreaks to have the optimal fence effect.

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Calculating the Mooring Force of a Large LNG Ship based on OCIMF Mooring Equipment Guidelines (OCIMF 계류설비지침 기반 대형 LNG선박 계류력 계산)

  • Wang, Jian;Noh, Jackyou
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.4
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    • pp.594-600
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    • 2022
  • When a large liquefied natural gas (LNG) carrier is anchored at a coastal terminal, calculations on mooring forces of mooring cables induced by environmental loads such as strong winds and currents are needed to secure mooring safety. The advantages and disadvantages of several existing mooring force calculation methods are compared and analyzed with their application conditions. Resultingly, mooring equipment guidelines of the Oil Companies International Marine Forum (OCIMF) are chosen as the computational method for this study. In this paper, the mooring forces of a large LNG carrier with spectrum was calculated using the OCIMF mooring equipment guidelines. The calculation shows similar maximum forces resulted from the calculation using experiment data of a wind tunnel test. To verify the results, OPTIMOOR, a dedicated mooring force calculation software, is used to calculate the same mooring conditions. The results of both calculations show that the computational method recommended by OCIMF is safe and reliable. OPTIMOOR calculates more detailed tensile force of each mooring cable. Thus, the calculation on mooring forces of mooring cables of a large LNG carrier using OCIMF mooring equipment guidelines is verified as an applicable and safe method.

A Study on the Effects of Wind Load of Membrane Roof Structures according to External Form (외형에 따른 지붕 막구조물의 풍하중 영향 고찰)

  • Ko, Kwang-Woong;Jang, Myung-Ho;Lee, Jang-Bog;Sur, Sam-Yeol
    • Proceeding of KASS Symposium
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    • 2008.05a
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    • pp.15-18
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    • 2008
  • A Spatial structure, having a curvature with a curved surface, is an extremely efficient mechanical creation considering the external load. It is resisted the out-of-plane direction load by in-plane forces using the structure's curvature. Spatial Structures include many types of structures, such as: space frames or grids; cable-and-strut and tensegrity; air-supported or air-inflated; self-erecting and deployable; cable net; tension membrane; lightweight geodesic domes; folded plates; and thin shells. Membrane structures, a kind of lightweight soft structural system, are used for spatial structures. It is very important that effects by wind load than seismic and dead load. And, wind load is different by surrounding and shape of building In this study, we analyze the results of design wind load and wind tunnel tests about the 2 stadiums which are constructed on sensitive sites by effect of wind loads.

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