• Wind and Structures
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• v.27 no.2
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• pp.111-121
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• 2018

Experiments were conducted in a large-scale Ward-type tornado simulator to study tornado-like vortices. Both flow velocities and the pressures at the surface beneath the vortices were measured. An interpretation of these measurements enabled an assessment of the mean flow field as well as the mean and fluctuating characteristics of the surface pressure deficit, which is a manifestation of the flow fluctuation aloft. An emphasis was placed on the effect of the aspect ratio of the tornado simulator on the characteristics of the simulated flow and the corresponding surface pressure deficit, especially the evolution of these characteristics due to the transition of the flow from a single-celled vortex to a two-celled vortex with increasing swirl ratio.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.262-267
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• 2008

The long-term wind data are reconstructed from the short-term meteorological data to design the 4 MW offshore wind park which will be constructed at Woljeong-ri, Jeju island, Korea. Using two MCP (Measure-Correlate-Predict) models, the relative deviation of wind speed and direction from two neighboring reference weather stations can be regressed at each azimuth sector. The validation of the present method is checked about linear and matrix MCP models for the sets of measured data, and the characteristic wind turbulence is estimated from the ninety-percent percentile of standard deviation in the probability distribution. Using the Gumbel's model, the extreme wind speed of fifty-year return period is predicted by the reconstructed long-term data. The predicted results of this analysis concerning turbulence intensity and extreme wind speed are used for the calculation of fatigue life and extreme load in the design procedure of wind turbine structures at offshore wind farms.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.504-511
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• 2010

After facing the fact such as fossil-fuel depletion, global warming, the Kyoto Protocol coming into force of mandatory reductions of carbon dioxide, the world is actively promoting the spread of the solar, wind, tidal, geothermal and other clean renewable energy technology development. Among them, wind power is the only alternative energy to secure a comparable price competition with fossil fuels because cheaper price power generation than other renewable energy when creating large-scale wind farm, thus wind power is the fastest growing industries in the world in the renewable energy field. Especially the offshore wind power is showing rapid growth as most of the wind power sector because of less changes of wind speed, no restrictions of land use, and large-scale development of offshore wind power. In this paper, the field of site selection and spatial location analysis techniques for development of large-scale offshore wind farm are discussed primarily. This paper shows overview of offshore wind power and establishment procedure for development of offshore wind farm.

• Journal of the Korean Solar Energy Society
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• v.32 no.1
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• pp.1-7
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• 2012

Predictions of wind speed for six different near-shore sites were made using the NCAR (National Center for Atmospheric Research) wind data. The distances between the NCAR sites and prediction sites were varied between 40km and 150km. A well-known wind energy prediction program, WindPRO, was used. The prediction results were compared with the measured data from the AWS(Automated Weather Stations). Although the NCAR wind data were located far away from the AWS sites, the prediction errors were within 9% for all the cases. In terms of sector-wise wind energy distributions, the predictions were fairly close to the measurements, and the error in predicting main wind direction was less than $30^{\circ}$. This proves that the NCAR wind data are very useful in roughly estimating wind energy in offshore or near-shore sites where offshore wind farm might be constructed in Korea.

• 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.

• International Journal of Contents
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• v.10 no.4
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• pp.75-82
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• 2014

The purpose of this paper was to identify suitable variables for financial distress prediction models and to compare the accuracy of MDA and LA for early warning signals for wind energy companies in Korea. The research methods, discriminant analysis and logit analysis have been widely used. The data set consisted of 15 wind energy SMEs in KOSDAQ with financial statements in 2012 from KIS-Value. We found that five financial ratio variables were statistically significant and the accuracy of MDA was 86%, while that of LA is 100%. The importance of this study is that it demonstrates empirically that financial distress prediction models are applicable to the wind energy industry in Korea as an early warning signs of impending bankruptcy.

• STI Policy Review
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• v.6 no.2
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• pp.146-173
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• 2015

This study explores how to reconcile science and policy in the wind energy sector by providing a conceptual framework for better understanding evidence-based policymaking (EBPM). Regarding this framework, the core issue is to discover how knowledge is formed over time, and which factors affect this knowledge formation. Comparative cases of wind industry emergence in Spain and Britain are examined. This analysis shows that knowledge formation initially starts in the scientific arena in parallel with its formation in the practical, and is followed by political knowledge formation near the beginning of commercial projects. Regarding knowledge formation, three more comparisons are made between wind industry emergence in Spain and Britain: the different approaches to R&D projects, the different adoptions of supporting measures, and the different ways of coping with public opposition. The factors affecting the comparisons are mainly perceptions of energy supply, nuclear power, environment and science and technology. Communication and unfamiliarity are likely to affect the comparisons in EBPM.

• Bulletin of the Korea Photovoltaic Society
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• v.6 no.1
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• pp.69-75
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• 2020

Mongolia is located between Russia and China in Central Asia. In coal-rich corners, both the energy and energy sectors of our country prevail. Mongolia has vast resources of renewable energy and limited hydropower plants, such as wind and solar. In their first iNDC (intended Nationally Determined Contributions) submitted in 2015, Mongolia has pledged to increase the share of renewables capacity to 20% by 2020, and 30% by 2030 while reducing their energy related GHG emissions.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.2
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• pp.95-112
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• 2002

A precision analysis was conducted for the quantification of trace metal levels in airborne particulates using ICP-MS. According to our study the quantitative analysis using Whatman grade 41 filters produces more precise and representative values of metal concentrations than that using EPM 2000 filters. The mean concentration of PM 10 analyzed during 1998 ~ 2000 was 82 $\mu$g/m$^3$. The concentrations of human carcinogens such as As and Cr were 8.65 and 25.87 ng/m$^3$, respectively, while those of probable human carcinogens such as Cd and Pb were 3.13 and 219.46 ng/m$^3$, respectively. Time-weighted mean concentration, calculated using surface wind speed and direction, indicated that there were differences between metals of crustal origin and metals of anthropogenic origin. The rectorial concentrations of anthropogenic metals and PM 10 were higher for north -west sector with calm or low wind speed conditions than for any other sector with high wind speed conditions. On the contrary, the rectorial concentrations of crustal metals were high with high wind speed. In addition, the sectorial concentrations of crustal metals were more affected by south-west wind directions, which were compared with those of anthropogenic metals. The enrichment factor (EF) values of many anthropogenic metals were higher than 50, while those of crustal metals were lower than 3, respectively. The concentrations of Cr and Ni in Daejeon industrial complex area were 11 times higher than those in the background site of Kuopio in Finland, while that of Pb in the complex area was 22 times higher, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.4
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• pp.1931-1938
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• 2012

This study evaluated whether the installed location of air quality monitoring stations is at an optimal level in an effort to improve the health and environmental quality of the surrounding areas of the Pohang Steel Complex. As a result of analyzing the atmospheric flow field, it was found that the location of air quality monitoring stations was acceptable in case of Daesong-myeon(The 1st Division of Local Wind Sector) and Jukdo-dong(The 3rd Division of Local Wind Sector). However, the air quality monitoring stations installed at Daedo-dong and Jukdo-dong is judged to have made an overlapped measurement because the stations existed at the Division of the same Wind Sector. Accordingly, this study suggests that the further air quality monitoring stations should be additionally installed at Buk-gu areas of Pohang where more than 50% of the population of Pohang is living presently. As a result of the analysis of air contaminant concentration distribution, the Jangheung-dong area showed higher concentration distribution than other areas in case of $PM_{10}$ while the Daesong-myeon area showed a comparatively higher concentration distribution in case of $O_3$. Conclusively, this study indicates that it is high time to prepare an aggressive management of $PM_{10}$ and $O_3$ which causes a harmful impact on the life and health of the residents of the target areas.