• Wind and Structures
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• v.13 no.4
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• pp.375-383
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• 2010

A three-dimensional flow simulation was performed to investigate the wind flow around wind-power generation facilities on mountainous area of complex terrain. A digital map of eastern mountainous area of Korea including a wind farm was used to model actual complex terrain. Rotating wind turbines in the wind farm were also modeled in the computational domain with detailed geometry of blade by using the frozen rotor method. Wind direction and speed to be used as a boundary condition were taken from local meteorological reports. The numerical results showed not only details of flow distribution in the wind farm but also the variation in the performance of the wind turbines due to the installed location of the turbines on complex terrain. The wake effect of the upstream turbine on the performance of the downstream one was also examined. The methodology presented in this study may be used in selecting future wind farm site and wind turbine locations in the selected site for possible maximum power generation.

• Journal of Animal Environmental Science
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• v.9 no.1
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• pp.27-34
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• 2003

This experiment was carried out to investigate the effect of dietary supplementation of fermented microbial complex(Eco-Farm$^{(R)}$) on performance of finishing pigs and indoor air quality in finishing building. A total 135 crossbred [(Landrace ${\times}$ Yorkshire) ${\times}$ Duroc] pigs were randomly arranged into nine groups and assigned to three treatments. Pigs were fed a basal diet supplemented with 0, 0.5 and 1% level of fermented microbial complex(Eco-Farm$^{(R)}$) until the market weight for 40 days of the experimental period. Average daily feed intake and feed conversion ratio were significantly improved (p<0.05) with dietary supplementation of 0.5% fermented microbial complex (Eco-Farm$^{(R)}$): however, average daily gain was not affected by dietary supplementation of fermented microbial complex(Eco-Farm$^{(R)}$). Indoor ammonia and hydrogen sulfide concentrations in the finishing building were significantly(p<0.05) decreased by dietary supplementation of fermented microbial complex(Eco-Farm$^{(R)}$) compared with those of control, however, indoor carbon dioxide concentration was not affected by dietary supplementation of fermented microbial complex(Eco-Farm$^{(R)}$). In conclusion, the results obtained from this experiment suggest that the dietary supplementation of fermented microbial complex(Eco-Farm$^{(R)}$) for finishing pigs improved performance and indoor air quality in the finishing building.hing building.

• Journal of Electrical Engineering and Technology
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• v.9 no.6
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• pp.1891-1899
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• 2014

A reliability model of wind farm located in mountainous land with complex terrain, which considers the cable and wind turbine (WT) failures, is proposed in this paper. Simple wake effect has been developed to be applied to the wind farm in mountainous land. The component failures in the wind farm like the cable and WT failures which contribute to the wind farm power output (WFPO) and reliability is investigated. Combing the wind speed distribution and the characteristic of wind turbine power output (WTPO), Monte Carlo simulation (MCS) is used to obtain the WFPO. Based on clustering algorithm the multi-state model of a wind farm is proposed. The accuracy of the model is analyzed and then applied to IEEE-RTS 79 for adequacy assessment.

• Journal of Wind Energy
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• v.14 no.4
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• pp.57-67
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• 2023

This study aimed to investigate differences in turbulence intensity and turbine loads among onshore wind farms located in various types of terrain. To achieve this, simulations were conducted for two onshore wind farms with identical wind turbines and capacity but situated on complex and flat terrains. The simulations used meteorological data gathered over a 10-year period from automatic weather stations nearest to the wind farms. WindSim and WindPRO software tools were employed for wind field and load analysis, respectively. The simulation results revealed that wind farm A, situated on complex terrain, exhibited significantly higher effective turbulence intensity than wind farm B on flat terrain, as expected. Consequently, the load indices of several wind turbines exceeded 100 % in wind farm A, indicating that the turbines could not reach their design lifespan. From the simulation study, aimed at reducing both the effective turbulence intensity and turbine loads, it became evident that while increasing turbine spacing could decrease effective turbulence intensity to some extent, it couldn't completely resolve the issue due to the inherently high ambient turbulence intensity on complex terrain. The problem with wind turbine loads could only be completely resolved by using wind turbines with a turbine class of A+, corresponding to a reference turbulence intensity of 0.18.

• Journal of the Korean Solar Energy Society
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• v.32 no.6
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• pp.1-10
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• 2012

The annual energy production of Gangwon wind farm was predicted for three consecutive years of 2007, 2008 and 2009 using commercial programs, WindPRO and WindSim which are known to be used the most for wind resource prediction in the world. The predictions from the linear code, WindPRO, were compared with both the actual energy prediction presented in the CDM (Clean Development Mechanism) monitoring report of the wind farm and also the predictions from the CFD code, WindSim. The results from WindPRO were close to the actual energy productions and the errors were within 11.8% unlike the expectation. The reason for the low prediction errors was found to be due to the fact that although the wind farm is located in highly complex terrain, the terrain steepness was smaller than a critical angle($21.8^{\circ}$) in front of the wind farm in the main wind direction. Therefore no flow separation was found to occur within the wind farm. The flow separation of the main wind was found to occur mostly behind the wind farm.

• Journal of the Korean Solar Energy Society
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• v.33 no.6
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• pp.1-11
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• 2013

The investigation on wind farm design using CFD technique was carried out to reduce turbulence intensity in a wind farm. A potential wind farm in Gasiri of Jeju Island was selected for the design and the commercial S/W of Meteodyn WT was used for applying CFD technique. The initial layout of wind turbines was derived using WindPRO which is mainly used for wind farm design in Korea. Then, the distribution of turbulence intensity on complex terrain was calculated and visible by Meteodyn WT. Based on the distribution, wind turbines were positioned properly. As a result, wind turbines could be deployed at positions with minimum turbulence intensity as well as maximum Annual Energy Production, AEP, using Meteodyn WT. It is necessary to take into account turbulence intensity in wind farm design to avoid wind turbine failure.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.6
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• pp.745-756
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• 2003

An analysis of wind environments using computational fluid dynamics and an evaluation of wind resources using measurement data obtained from meteorological observation sites at Homi-Cape, Pohang have been carrid out for siting a wind farm. It was shown that a numerical simulation using computational fluid dynamics would provide reliable wind resource map in complex terrain with land-sea breeze condition. As a result of this investigation, Homi-Cape wind farm with 11.25 ㎿ capacity has been designed for maximum power generation and 25.7 GWh electricity production is predicted.

• Korean Journal of Agricultural Science
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• v.39 no.2
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• pp.263-270
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• 2012

The vitalization of Agro-industrial complex could be an alternative to enhance farmers off-farm income and overcome FTA's impacts on the import of agricultural products. However, it is evaluated the governmental policy on the Agro-industrial complex has not been successfully done as expected. The Agro-industrial complex started to be composed in 1984 and the 427 Agro-industrial complex have been composed nationwide by 2011. Meanwhile, three Agro-industrial complex where 61 factories are running have been composed and two Agro-industrial complex are being under construction in Seocheongun as of 2011. It is investigated that there are constraints in the government supporting systems for Agro-industrial complex. They are; Aged and poor infrastructure facilities, Weak marketing competition, Scattered supporting agencies, and Poor loan system, etc. In this respect, the policy of supporting system was suggested and recommended to vitalize Agro-industrial complex in the study. They are; Better loan system, Improving aged facilities, Marketing support, Assisting technology, Suppling labor power, and Forming factory-network, etc.

• Journal of Environmental Science International
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• v.25 no.3
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• pp.457-464
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• 2016

The most wind farm development process in Korea still have not been defined since the history of the wind farm development experiences are very short compared to EU and other developed countries. Therefore, most wind farm development company and researchers have a lot of trouble to implement the wind farm development and need a guideline for the process. Establishing the wind farm needs a complex processes such as transportation system, construction conditions, natural environment and wind conditions etc. Specially, for the restricted development area, the social negotiation and legal minds are necessary. In the case, the decision making process of suitable wind farm area using GIS tool is very useful. However, before using GIS technique, we should understand the development processes and the items for surveying tools. Recently, suitability analysis of selecting Onshore Wind Farm has been studied to consider exclusion analysis to solve the limited develop condition problem. This paper proposed the onshore wind farm development process which can suitable to Korea wind farm environment based on European guideline with GIS tool. To estimate the processes, the processes are divided into two parts, the basic design and wind farm planning. Next, the planning stages are classified into five stages in which the factors for each step were considered.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.123-126
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• 2011

To investigate the forecasting of plant disease and insect for an agricultural complex and farm in environment-friendly cultivation of Rice, environment-friendly agricultural five complexs and five farms were selected in Youngam and Naju area, Jonnam, Korea. Preventation objects of plant disease and insect were leaf blast, neck blast, sheath blight, bacterial leaf blight, and hopper. Factors of sheath blight occurrence in environment-friendly agricultural complex were a fast transplanting time and a narrow planting density. Bacterial leaf blight in rice occurred severely in the area under water. Rice growth in environment-friendly agricultural complex was decreased heavy drying by hopper appearance.