• Wind and Structures
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• 제5권2_3_4호
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• pp.227-244
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• 2002

Recently, the prediction of wind environment around a building using Computational Fluid Dynamics (CFD) technique comes to be carried out at the practical design stage. However, there have been very few studies which examined the accuracy of CFD prediction of flow around a high-rise building including the velocity distribution at pedestrian level. The working group for CFD prediction of wind environment around building, which consists of researchers from several universities and private companies, was organized in the Architectural Institute of Japan (AIJ) considering such a background. At the first stage of the project, the working group planned to carry out the cross comparison of CFD results of flow around a high rise building by various numerical methods, in order to clarify the major factors which affect prediction accuracy. This paper presents the results of this comparison.

• 한국환경과학회지
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• 제30권7호
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• pp.557-571
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• 2021

This study aimed to classify typhoons using a more objective index based on strong winds and precipitation data from 1904 to 2019 obtained from the Automated Surface Observing System. The Typhoon Type Index (TTI) was calculated by classifying wind speed and precipitation of each typhoon, thereby revealing the rate and characteristics of the wind-type and rain-type typhoons. In addition, the top 10 typhoons for property damage were analyzed by dividing them into three types according to the typhoon course. The analysis showed that typhoons of type 1, heading north to the west coast, were most clearly affected by the wind. In addition, the impact of the wind was reduced and the impact of rain increased in the order of typhoon type 2 that landed on the southern coast and type 6 that affected the Korean Peninsula through China.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.189.1-189.1
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• 2010

The wind farm where the wind velocity condition is excellent and economical can be established to produce power with the multiple wind power turbine. The wind velocity which is suitable to Wind Power Development must be evaluated for searching the economical wind farm on planning the wind farm. In this paper, based on wind speed data at 24 locations in Korea from 1971 through 2009, the basic wind velocity which can be applied to designing wind power development is estimated using the statiscal process. The wind velocity which is measured from observation stations is revised according to wind gauge's height and Circumferential environment. The wind speeds for 200 year's return period in 24 locations are determined using the Gumbel's distribution.

• 한국대기환경학회지
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• 제20권1호
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• pp.1-15
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• 2004

Sea/land circulation system is a representative mesoscale local circulation system in coastal area. In this study, wind fields around coastal area. Pohang, which is affected by this system was investigated and its detailed characteristic analysis was carried out. The following can be found out from the numerical simulation. Generally, at nighttime mountain winds prevail and land breeze toward the coastal area was well simulated During daytime, valley wind and sea breeze was simulated in detail. Especially, as a result of analyzing the land breeze path, it could be found along the coastline as it flows out through low land coastal area. In order to investigate the accuracy of model results. wind speed, temperature and wind direction of continuous typical sea/land breeze occurrence day was compared with observation data. Analyzing the characteristics of local circulation system was very hard because of horizontally sparse observation data but from the above result, a numerical simulation using RAMS, which satisfies the spatial high resolution, will provide more accurate results.

• 한국대기환경학회지
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• 제18권1호
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• pp.1-10
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• 2002

A three-dimensional numerical model which involved the nesting method was developed to reproduce the wind circulation of Kwangyang Bay area which comprises complicated mountains and sea topograph. The calculated results indicated geographical effects of Kwangyang Bay area, sea/land breezes and mount-valley wind which are local circular winds. We also noticed that the northern inland area of Kwangyang Bay formed the very complex wind systems under the influence of such geographic effects when a land breeze was not formed. A good agreement was found between predicted and observed values of temperature. In addition, the calculated results of the wind direction and the wind velocity are in accord with the observed values. They showed only a slight difference in between predicted and the observed values, when the sea breeze and the land breeze are changing.

• 한국대기환경학회지
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• 제8권3호
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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.

• Wind and Structures
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• 제7권3호
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• pp.203-214
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• 2004

This paper describes a method for developing a multi-degree-of freedom aero-elasto-plastic model of a base-isolated mid-rise building. The horizontal stiffness of isolators is modeled by several tension springs and the vertical support is performed by air pressure from a compressor. A lead damper and a steel damper are modeled by a U-shaped lead line and an aluminum line. With this model, the frequency ratio of torsional vibration to sway vibration, and plastic displacements of isolation materials can be changed easily when needed. The results of isolation material tests and free vibration tests show that this model provides the object performance. The peak displacement factors are about 4.5 regardless of wind speed in wind tunnel tests, but their gust response factor decreases with increment of wind speed.

• 한국조경학회지
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• 제31권3호
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• pp.58-73
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• 2003

It is well known that urban environment affects climate, as we can see in the quality of bio-climate. However, climate has not been recognised properly in the urban planning process. The role it flays needs to be examined for better urban environment. The main objective of this study is to investigate the climate-ecological priority area which produces cold fresh air and thermal induced wind circulation between rural and urban areas. The objective is also to improve the quality of bio-climate and wind circulation at blocked urban areas. This paper uses the measurement and analysis method of wind direction and wind speed in order to investigate the climate-ecological priority area and cold fresh air corridor. In this study, local climate conditions i.e. wind speed, wind direction, temperature, humidity etc., were measured at nine fields and analyzed. On the basis of the climate measurement, the climate ecological priority areas were delineated; These will be assigned as climate-ecological conservation areas.

• Journal of Astronomy and Space Sciences
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• 제39권3호
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• pp.79-86
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• 2022

Thermospheric wind observations from high to mid latitudes are compared with the newly developed Multiscale Atmosphere Geospace Environment (MAGE) model for the Nov 3-4 geomagnetic storm. The observation and simulation comparison shows a very good agreement and is better at high latitudes in general. We were able to identify a thermospheric poleward wind reduction possibly linked to a northward turning of the Interplanetary Magnetic Field (IMF) at ~22 UT on Nov 3 and an enhancement of the poleward wind to a southward turning near 10 UT on Nov 4 at high latitudes. An IMF southward turning may have led to an enhancement of equatorward winds at Boulder, Colorado near midnight. Simultaneous occurrence of aurora may be associated with an IMF By turning negative. The MAGE model wind simulations are consistent with observations in these cases. The results show the model can be a very useful tool to further study the magnetosphere and ionosphere coupling on short time scales.

• 한국지구과학회지
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• 제28권7호
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• pp.891-902
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• 2007

실험을 통한 한국형 체감온도지수를 개발하기 위하여 실험을 수행할 경우 필요한 피험자의 선발과정, 실험의 정확도, 피험자의 안전 및 실험에서 발생하게 될 여러 가지 상황을 대비하기 위해서 예비실험을 실시하였다. 예비실험에서는 저온에 의한 인체의 영향을 최소화하기 위해 영상 $5^{\circ}C$에서 풍속을 무풍에서 강풍으로 변화시키면서 실험조건과 인체의 안전에 대해 살펴보았다. 그 결과, 안면부 부위별 피부온도변화의 경우 얼굴의 오른쪽 부위이 기온과 풍속변화에 가장 민감하여 안정적인 변화경향을 나타내었으며 모든 피험자가 얼굴의 오른쪽 부위에서 가장 낮은 온도를 보였다. 성별에 따른 차이에서는 여성이 남성보다 더 민감하게 반응하였으며, 약한 풍속에서 피부온도가 크게 변화함을 알 수 있었으며, 기준풍속에 따른 영향은 체감온도지수 개발시 고려하지 않는 것이 바람직함을 알 수 있었다.