• Title/Summary/Keyword: HydroKorea

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A Framework for Investment Justification and Economic Operation- (한국의 다목적댐 수력발전 체계-투자의 정당화와 경제적 운영-)

  • 이승규;박용삼
    • Journal of the Korean Operations Research and Management Science Society
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    • v.12 no.1
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    • pp.157-157
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    • 1987

  • Hydro-electric power generation from multi-purpose dams has been playing important roles in the electric power supply network in Korea. Although the total share of hydro power in national electricity supply now becomes very small, the peak-shaving and frequency control capability of hydro power helps the power company enormously in maintaining the quality of power. But since the company that builds and operates the multi-purpose dams in Korea has to sell all the electricity produced to the monopolistic utility, there have been various problems in justifying the investment, designing pricing mechanism, and controlling operations of the power plants. In addition, economic evaluation of the hydro power has been distorted by a variety of reasons and hence it has been very difficult to encourage effective development and utilization of national water resources. To make the problem worse, both parties are public companies with X-inefficiency problems. Thus, changing environment requires to reengineer the system that governs hydro power generation. We address the problems of Korean hydro-electric power generation system in four areas: the investment justification process, the operations decison right of the hydro power plants, the pricing of the purchased-power, and the negotiation of contract revision. Then we propose improvement directions of new hydro-electric power system in view of static and dynamic efficiency, X-inefficiency and equity.

Runner Design and Internal Flow Characteristics Analysis for an Ns=200 Francis Hydro Turbine Model

  • Hwang, Yeong-Cheol;Chen, Zhenmu;Choi, Young-Do;Lee, Young-Ho
    • Journal of Advanced Marine Engineering and Technology
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    • v.40 no.8
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    • pp.698-703
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    • 2016

  • Francis hydro turbines have been most widely used throughout the world because of their wide range of head and flow rate applications. In most applications, they are used for high heads and flow rates. Currently, Korea is developing technology for Francis hydro turbine design and manufacture. In order to understand the internal details of Francis hydro turbines further, a new Francis turbine model runner is designed and model internal flow characteristics are investigated. The specific speed of the Francis hydro turbine model runner is $Ns=200m-kW-min^{-1}$. The runner blade is designed successfully according to the port area and one-dimensional loss analysis. The best efficiency point of the Francis hydro turbine model achieves 90% at the design condition. CFD analysis yields a hill chart of the Francis hydro turbine model for use in predicting performance.

  • https://doi.org/10.5916/jkosme.2016.40.8.698 인용 PDF KSCI

The potential impact of low dose ionizing ${\gamma}$-radiation on immune response activity up-regulated by Ikaros in IM-9 B lymphocytes

  • Kim, Sung-Jin;Jang, Seon-A;Yang, Kwang-Hee;Kim, Ji-Young;Kim, Cha-Soon;Nam, Seon-Young;Jeong, Mee-Seon;Jin, Young-Woo
    • 대한방사선방어학회:학술대회논문집
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    • 2011.11a
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    • pp.212-213
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    • 2011

  • The biological effects of low dose ionizing radiation (LDIR) remain insufficiently understood. We examined for the scientific evidence to show the biological effects of LDIR using radiation-sensitive immune cells. We found that Ikaros protein was responsed to low dose-dependent effects of gamma radiation in IM-9 B lymphocytes. Ikaros encodes zinc finger transcription factors that is important regulators of a hematopoietic stem cells (HSCs) progression to the B lymphoid lineage development, differentiation and proliferation. In this study, we observed that cell proliferation was enhanced from 10% to 20% by LDIR (0.05 Gy) in IM-9 B lymphocytes. The Ikaros protein was phosphorylated in its serine/threonine (S/T) region and decreased its DNA binding activity in the cells exposed to LDIR. We found that Ikaros phosphorylation was up-regulated by CK2/AKT pathway and the residues of ser-304 and ser-306 in Ikaros was phosphorylated by LDIR. We also observed that Ikaros protein was localized from the nucleus to the cytoplasm after LDIR and bound with Autotaxin (ENPP2, ATX) protein, stimulating proliferation, migration and survival of immune cells. In addition, we found that the lysoPLD activity of ATX was dependent on Ikaros-ATX binding activity. These results indicate that the Ikaros is an important regulator of immune activation. Therefore, we suggest that low dose ionizing radiation can be considered as a beneficial effects, stimulating the activation of immune cells.

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