• Title/Summary/Keyword: wind resources

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Studies on the Desertification and Sand Industry Development(II) - Analysis of Silvicultural Techniques and Effects of Landscape-Eco Shelterbelt Establishment - (사막화방지(沙漠化防止) 및 방사기술개발(防沙技術開發)에 관한 연구(硏究)(II) - 중국(中國)의 경관(景觀)-생태(生態) 방호림조성기술(防護林造成技術) 및 효과분석(效果分析) -)

  • Woo, Bo-Myeong;Lee, Kyung-Joon;Jeon, Gi-Seong;Kim, Kyung-Hoon;Choi, Hyung-Tae;Lee, Seung-Hyun;Lee, Byung-Kwon;Kim, So-Yeon;Lee, Sang-Ho;Jeon, Jeong-Ill
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.3 no.3
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    • pp.81-99
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    • 2000
  • The shelterbelts are very important to conserve and protect the sandy land, vegetation coverage, farmland, livestock and human life in the desertified land. The shelterbelts are constructed by the several row-plantings of high-adaptable species in the desertified land. The shelterbelts have various kind of type, and there are shelterbelts for conservation of farmland in dry the region, the protective shelterbelts (windbreaks for blowing-sand, artificial sanddune fixation by revegetation, and construction of farmland shelterbelts to protect farmland and pasture from wind erosion, etc.) in the semi-dry steppe, shelterbelts around the villages and oasis for sanddune fixation, shelterbelts for protection of railroads, and so on. The shelterbelts consist of main she1terbelts and minor shelterbelts. The main shelterbelts were constructed by being perpendicular to main wind direction, and the minor shelterbelts were constructed by being perpendicular to the main shelterbelts. Generally, the width of shelterbelts is 8~20m, and the number of row-planting is 4~10. The grid sizes of shelterbelts networks are $400{\times}400m$, $300{\times}500m$, $100{\times}200m$, and so on, and there are ventilation type and closing type in the type of shelterbelt. The width, number of row-planting, grid size and type of shelterbelt are selected by the local characteristics. The effects of shelterbelts are mainly the climate improvement and mitigation, such as prevention of occurrence of strong wind, cold wind and blowing-sand. And, the other effects of shelterbelts are effect of reforestation, increase of agricultural productions, establishment of greenbelts and green forests, construction of landscape-eco shelterbelts, improvement of life environment of local villages, supply of fuel wood and agricultural wood, land amelioration, effect of revegetation and restoration of desertified land, and so on. The kinds of the tree species mainly used for the construction of shelterbelts have differences between regions, but main species are Populus euphratica, Populus simonii, Populus bolleana, Populus tomentosa, Salix flavida, Salix mongolica, Tamarix chinensis, Hedysarum scoparium, and so on.

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Design of Drag-type Vertical Axis Miniature Wind Turbine Using Arc Shaped Blade (아크형 날개를 이용한 항력식 수직축 소형 풍력 터빈 설계)

  • Kim, Dong-Keon;Kim, Moon-Kyung;Cha, Duk-Keun;Yoon, Soon-Hyun
    • The KSFM Journal of Fluid Machinery
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    • v.9 no.2 s.35
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    • pp.7-12
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    • 2006
  • This study is to develop a system of electric power generation utilizing the wind resources available in the domestic wind environment. We tested drag-type vortical wind turbine models, which have two different types of blades: a flat plate and circular arc shape. Through a performance test, conditions of maximum rotational speed were found by measuring the rpm of wind turbine. The rotational speed was measured by a tachometer in a wind tunnel and the tunnel wind speed was by using a pilot-static tube and a micro manometer. The performance test for a prototype was accomplished by calculating power, power coefficient, torque coefficient from the measurement of torque and rpm by a dynamometer controller From the measurements for miniature turbine models with two different blades, the circular arc shape was found to Produce a maximum rotational speed for the same wind velocity condition. Based on this result, the prototype with the circular arc blade was made and tested. We found that it produces 500W at the wind velocity of 10.8 m/s and the power coefficient was 20%.

Characteristics of Efficient Radius of Meteorological Observation Data to Estimate Regional Wind Energy (국지규모 풍력에너지 평가를 위한 기상 관측 자료의 영향 반경 특성)

  • Lee, Soon-Hwan;Kim, Min-Jung;Lee, Hwa-Woon
    • Journal of Korean Society for Atmospheric Environment
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    • v.23 no.5
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    • pp.585-595
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    • 2007
  • Representative impacts and effectiveness of surface meteorological observation data assimilation were examined in order to use wind resources estimation around southern coastal area of the Korean Peninsula. The data used in study are observational wind and temperature data at 5 and 41 sites of Regional Meteorological Offices and Automatical Weather Systems, respectively. Observation wind speed data tends to show small effective radius with limited area. Especially assimilation impacts of data observed at peninsula type sites like Yeosu play only around the inside of the peninsula. This limited effective radius for wind speed is caused by the strong correlation between topography and wind speed. And the efficient radius for surface air temperature is larger than that of wind. Data assimilation for observational air temperature is useful to increase the accuracy of wind energy estimation. However assimilation of wind data requires special care in its application due to high sensitivity of topographical complexity.

Field Testing and Performance Evaluation of 1.5 kW Darrieus Wind Turbine (1.5 kW 다리우스 풍력터빈 현장 실증 및 성능분석)

  • ALI, SAJID;JANG, CHOON-MAN
    • Transactions of the Korean hydrogen and new energy society
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    • v.30 no.6
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    • pp.608-613
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    • 2019
  • The purpose of the present study is to analyze and evaluate the performance of a small Darrieus wind turbine installed at the Urumsil region of Deokjeok-do Island in the west of South Korea 50 km away from Incheon. This place has no government electricity so alternate resources of energy needed to be installed there. For this purpose a small Darrieus wind turbine with the capacity of 1.5 kW was developed and installed at the site. The experimental power output of the wind turbine is less than the designed power at the same values of wind speed. This power loss is mainly due to the highly unsteady nature wind of sudden changes in magnitude of wind speed and wind angle. The results of current study can be used to make a future power generation plan for Deokjeok-do and other nearby small islands.

A Study of Improvement of a Prediction Accuracy about Wind Resources based on Training Period of Bayesian Kalman Filter Technique (베이지안 칼만 필터 기법의 훈련 기간에 따른 풍력 자원 예측 정확도 향상성 연구)

  • Lee, Soon-Hwan
    • Journal of the Korean earth science society
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    • v.38 no.1
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    • pp.11-23
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    • 2017
  • The short term predictability of wind resources is an important factor in evaluating the economic feasibility of a wind power plant. As a method of improving the predictability, a Bayesian Kalman filter is applied as the model data postprocessing. At this time, a statistical training period is needed to evaluate the correlation between estimated model and observation data for several Kalman training periods. This study was quantitatively analyzes for the prediction characteristics according to different training periods. The prediction of the temperature and wind speed with 3-day short term Bayesian Kalman training at Taebaek area is more reasonable than that in applying the other training periods. In contrast, it may produce a good prediction result in Ieodo when applying the training period for more than six days. The prediction performance of a Bayesian Kalman filter is clearly improved in the case in which the Weather Research Forecast (WRF) model prediction performance is poor. On the other hand, the performance improvement of the WRF prediction is weak at the accurate point.

Estimation Method of Potential Biomass Resources in Korea (국내 바이오매스 자원 잠재량 산정방법)

  • Lee, Joon-Pyo;Hwang, Kyung-Ran;Park, Soon-Chul
    • 한국태양에너지학회:학술대회논문집
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    • 2008.11a
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    • pp.332-336
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    • 2008
  • The resource potentials biomass resources of South Korea are estimated as Preliminary stage using relevant National statistics. Biomass resources possibly be collected, used and converted to bioenergy in Korea are forest biomass, agricultural residue, livestock manure and municipal solid wastes. The potential biomass resources are classifying into total potential, available potential and technically feasible biomass resources, Total potential biomass resources in Korea are estimated to be around 140million tons of oil equivalent (toe). Available potentials are estimated to be around 11million annually. The technically feasible biomass resources with current technologies are estimated to be 2.3million toe annually. These estimated values are the minimum of all potentials since they are all estimated from explicit statistics. Although actually there exist huge amount of biomass on the land as well as in the sea, potential resources for bioenergy are believed to be limited. The potentials are to be inclosed with the improvement of bioenergy technologies.

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Friable Test and Risk Assessment for Asbestos in Soils using the Releasable Asbestos Sampler (RAS) (석면 비산 장비를 이용한 토양 중 석면 비산 특성 및 위해성 평가)

  • Kim, In Ja;Kim, Jeong-Wook;Ryu, Hyun Sik;Jung, Myung Chae
    • Journal of Soil and Groundwater Environment
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    • v.17 no.5
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    • pp.68-74
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    • 2012
  • The objective of this study is to examine a releasable asbestos sampler developed for measuring friable asbestos from soil to air controlled by wind velocity and water contents. Asbestos contaminated soil with 3.75% at the Sinsuk-asbestos mine was sampled, air-dried and sieved to 100 mesh, then homogenized during 24 hours' agitation. Various wind velocities, 1 m/s, 2 m/s, 3 m/s, and 5 m/s, were applied to evaluate releasable characteristics of the releasable asbestos sampler. In addition, soils with 1.0%, 3.4%, 4.4%, 11.0%, 16.2%, and 20.0% of water contents were also examined the amount of friable asbestos by the releasable asbestos sampler. Collected soil and air samples were analyzed by polarized light microscopy (PLM) and phase contrast microscopy (PCM), respectively. Those contents were applied to calculate an excess life cancer risk (ELCR). This study also discussed the relationship with risk assessment by a weeding scenario of activity based sampling (ABS) and field applied releasable asbestos sampler. The result was shown that friability of asbestos in soil increased with wind velocity and decreased with water content. In comparison with ELCR results, over 10E-4 of cancer risk was found in condition on < 5% water content and > 3m/s wind velocity.

Current Status and Prospects of Ukrainian Wind Energy (우크라이나 풍력발전 현황 및 전망)

  • Kim, Hyun-Goo;Park, Hi-Chun
    • New & Renewable Energy
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    • v.7 no.1
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    • pp.8-14
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    • 2011
  • As is the case in Korea, the expansion of renewable energy dissemination is an essential matter in Ukraine when considering its energy consumption and dependence on energy import. While Korea has set about promoting the new and renewable energy industry on the back of the national policy on green growth, Ukraine expects a virtuous circle of renewable energy industry with green tariffs and the attraction of foreign capital in association with carbon emission trade. Utilizing its well-developed heavy industrial sector including the shipbuilding and automobile industries, Korea expects wind turbine manufacturing to become one of its next-generation growth engines. Ukraine is also trying to enter the wind turbine system or parts manufacturing industry based on its automobile industry and advanced aerospace technology. Although the Crimean region in Ukraine seems to have excellent wind resources, and thus shows great potential as a location for wind farm development, political instability has been a major obstacle to the attraction of foreign capital, leading to delayed investment.

A Study on the Development of Cross-flow Type Vertical Axis Wind Turbine (횡류형 수직축 풍력터빈 개발에 관한 연구)

  • Hwang, Yeong-Cheol;Choi, Young-Do;Kim, Ill-Soo;Lee, Young-Ho
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.493-493
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    • 2009
  • Recently, small vertical axis wind turbine attracts attention because of its clean, renewable and abundant energy resources to develop. Therefore, a cross-flow type wind turbine is proposed for small wind turbine development in this study because the turbine has relatively simple structure and high possibility of applying to small wind turbine. The purpose of this study is to investigate the effect of the turbine‘s structural configuration on the performance and internal flow characteristics of the cross-flow turbine model using CFD analysis. The results show that guide nozzle should be adopted to improve the performance of the turbine. Optimization of the nozzle shape will be key-importance for the high performance of the turbine.

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Comparison between Expected and Actual Capacity Factors of a Wind Farm (풍력발전단지의 예측이용율과 실제이용율 비교분석에 관한 연구)

  • Koh, Byung-Euk;Moon, Seung-Jae;Yoo, Hoseon
    • Plant Journal
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    • v.7 no.1
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    • pp.40-48
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    • 2011
  • This study shows the comparison between expected and actual capacity factors of a wind farm through wind resource analyzation. The expected capacity factor comes from an 'automatic weather system' run by the Korean national weather service and a 'meteorological mast' run by a project owner. Based on this comparison and analysis, the importance of meteorological mast micro-siting and selection of wind turbine class and type, will be studied along with presenting important implications for wind farm expansion and development.

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