• Journal of the Korean Institute of Navigation
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• v.18 no.1
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• pp.23-30
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• 1994

By use of the Climatological Report(1982~1991) and the Marine Casualty Report(1982`1992), marine casualties caused by meteorological factors and climatic characteristics along Korean coast were analysed. Marine casualty by meteorological factors can be classified into three kinds such as collision, aground and sinking. On the whole collision was mainly caused by dense fog and heavy precipitation, and aground and sinking was caused by strong wind and high sea. As results of analysis of the distribution of wind, fog and precipitation at major ports in Korea, climatic characteristics along Korean coast are as follows. in the eastern coast, wind was relatively weak and fog was not so frequently formed, while strong wind blew all the year round and fog appeared from April to August in Ulleung Island. In the southern coast, the wind was strong in both winter and summer, fog formed frequently in late spring through mid-summer and heavy precipitation was in summer. Typhoon affecting Korea was usually passing this area to the East Sea. In the western coast, strong wind was prevailing in winter at southern region and fog was formed very frequently throughout the year.

• Journal of the Korean Solar Energy Society
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• v.23 no.2
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• pp.35-41
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• 2003

In order to investigate the offshore wind resources around Korean peninsula, the "QuikSCAT Level 3" data by ADEOS II satellite was analyzed from Jan 1 2000 to Jan 18 2003. The "SeaWinds" on the satellite is a specialize4 device for microwave scatterometery that measures near-surface wind speed and direction under all weather and cloud conditions. Wind speed are extrapolated from 10m to 60m with the exponent of 1/10 in the power law model. It has been found that the High wind energy potentials are prevailing in the South sea and Southeastern end of Korean peninsula.

• Journal of Environmental Science International
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• v.9 no.6
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• pp.475-482
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• 2000

The purpose of this study is to find out the temporal and spatial characteristics of the diurnal wind variation between coastal and inland areas using the hourly wind data of 58 AWS-stations in the South Korea which are collected during the 10 years from 1980. Diurnal variation is investigated by using the Fast Fourier Transform(FFT), and the wind direction in investigated by comparing C(sub)r with C(sub)v represented the constancy of wind. For the scalar wind speed, the maximum wind speed occurs in the daytime 14h to 16h. The maximum diurnal amplitude at coastal areas occurs from 12h to 16h, and is about 2 hours faster than that at inland areas. Vector mean wind speed is strong at coastal areas and Chupungnyong, Kumi, Taegu of inland areas. The diurnal variation ellipses make a right angle with coastline show that the land and sea breezes are prevailing. The constancy of wind is strong at all observations in January. In the relationship between $C_r and C_v, C_v is higher than C_r$.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.17 no.1
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• pp.39-45
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• 2009

An Analysis of wind is essential for planning runway direction. As a general rule, the principal traffic runway at an airport should be oriented as closely as practicable in the direction of the prevailing wind. Aircraft are able to maneuver on a runway as long as the wind component at right angles to the direction of landing and taking-off, the cross wind component, is not excessive. ICAO recommends that runway be oriented so that aircraft may be landed at least 95% of the time with allowable cross wind components not exceeding specified limits based upon the airport reference field length. Based on the recommendation, the direction of the runway or runways at an airport can be determined through graphical vector analysis on wind rose. This study is to develop the wind-rose software for planning the optimum runway direction at an airport with the raw wind data based on reliable wind distribution statistics that extend over as long as a period as possible, preferably of not less than 5 years.

• Plant Journal
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• v.12 no.3
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• pp.32-38
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• 2016

In this study, the effect of wake on the energy production of a downstream wind turbine was analyzed on the base of operation practices of wind farm in the coastal complex terrain which has 2 row array of wind turbines. And changes in the variation of wind speed and turbulence intensity was analyzed. In case wind turbines are spaced 4-rotor diameter-apart in the prevailing wind direction, reduction in energy production was confirmed due to the decrease of wind speed and the increase of turbulence intensity by wake. Especially a radical change of wind direction caused wind turbine a sudden stop and energy production significantly reduced. It is considered improvement of yaw brake can prevent the sudden stop and increase energy production.

• Journal of the Korean Solar Energy Society
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• v.30 no.2
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• pp.46-53
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• 2010

In this paper the feasibility of wind power forecasting from MOS(Model Output Statistics) was evaluated at Gosan area in Jeju during February to Octoberin 2008. The observed wind data from wind turbine was compared with 24 hours and 48 hours forecasting wind data from MOS predicting. Coefficient of determination of measured wind speed from wind turbine and 24 hours forecasting from MOS was around 0.53 and 48 hours was around 0.30. These determination factors were increased to 0.65 from 0.53 and 0.35 from 0.30, respectively, when it comes to the prevailing wind direction($300^{\circ}\sim60^{\circ}$). Wind power forecasting ratio in 24 hours of MOS showed a value of 0.81 within 70% confidence interval and it also showed 0.65 in 80% confidence interval. It is suggested that the additional study of weather conditions be carried out when large error happened in MOS forecasting.

• Wind and Structures
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• v.15 no.2
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• pp.147-162
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• 2012

Argentina is a large country with several areas dominated by different climate mechanisms. Since 2008, damage to civil structures caused by strong winds has been surveyed in Chaco and the neighbouring areas. Chaco is a province of NEA, the north-east region of the Argentina, which also includes the provinces of Formosa, Corrientes and Misiones. The strong wind events in NEA are related to severe convective storms. In this work, we present findings about wind-induced damage in NEA and the prevailing meteorological conditions. We emphasise seven particular cases for which the conditions of the atmosphere were reconstructed through reanalysis.

• Journal of the Korean Institute of Navigation
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• v.20 no.3
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• pp.13-30
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• 1996

It is general that large ships entering or leaving a port located in the East coast of Korean peninsular are often exposed athwart to swell while maneuvering in the vicinity of breakwater at harbor enterance or to prevailing wind inside the port in winter. Particulary, Many VLCCs laden with ore coal are calling at Pohang Port, on account of which it is likely that one of those VLCCs block the port if they were to run aground in fairway due to adverse circumstance of swell, prevailing winds or improper shiphandling. This accident may result in delay of delivery of raw material for Pohang Steel Mill which will bring about shortcomings of steel products for nationwide relevant industries causing national economic shock. Therefore, This study basically aims at establishment of certain criteria for safe unberthing of VLCC in this port to prevent such unexpected disaster because any VLLC is highly affected by external forces when in ballast condition. Computer simulations are unavoidable to fulfull this study successfuly and many simulations have been carried out repeatedly to find a model of safe unberthing under various unfavourable wind conditions. The "PC-based ship maneuvering simulator for training purpose" was used to perform numerous simulations at the least economic burden and to verify its availability that it can be used not only for training but also some other purposes. purposes.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.571-574
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• 2010

Large-eddy simulation has been conducted to simulate turbulent boundary-layer flows over an array of regularly distributed obstacles considering various cases of a wind incident angle. The effect of wind direction was investigated in the square cube array that periodic boundary condition was imposed. Characteristics of the turbulent flow over the obstacle array have been found to be very sensitive to the direction of prevailing wind or of mean wind or of mean pressure gradient but varied with height, specially below the urban canopy. Turbulent statistics are changed sensitively with the direction of mean pressure gradient around 10 degree.

• Journal of Environmental Science International
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• v.13 no.4
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• pp.367-376
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• 2004

In urban area, thermal pollution associated with heat island phenomena is generally regarded to make urban life uncomfortable. To overcome this urban thermal pollution problem, urban planning with consideration of urban climate, represented by the concept of urban ventilation lane, is widely practiced in many countries. In this study, the prevailing wind ventilation lane of a local winds in Daegu during the warm climate season was investigated by using surface wind data and RAMS(Reasonal Atmospheric Model System) simulation. The domain of interest is the vicinity of Daegu metropolitan city(about 900 $km^{2})$ and its horizontal scale is about 30km. The simulations were conducted under the synoptic condition of late spring with the weak gradient wind and mostly clear sky. From the numerical simulations, the following two major conclusions were obtained: (1)The major wind passages of the local circulation wind generated by radiative cooling over the mountains(Mt. Palgong and Mt. Ap) are found. The winds blow down along the valley axis over the eastern part of the Daegu area as a gravity flow during nighttime. (2)After that time, the winds blow toward the western part of Daegu through the city center. As the result, the higher temperature region appears over the western part of Daegu metropolitan area.