• Journal of the Korean Society of Industry Convergence
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• v.5 no.1
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• pp.39-43
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• 2002

In present much CMOS devices used in VLSI circuit and Logic circuit. With increasing a number of device in VLSI, the confidence becomes more serious. This paper describe the mechanism of breakdown on CMOS, especially n-MOS, based on Hydro Dynamic model with device self-heating. Additionally, illustrate the CMOS latch-up characteristics on simplified device structure on this paper.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2007.11a
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• pp.175-176
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• 2007

• 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.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.2
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• pp.173-181
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• 2010

This study was conducted to investigate the possible installation of small hydro-power plant at the discharge point of Gumi sewage treatment plant (STP) using treated wastewater. Sufficient amount of water to transfer to electric power and the selection of proper location are two essential elements for the construction of small hydro-power facility. Preliminary analysis based on site visit and existing data in Gumi STP were made. Capacity of the small hydro-power plants and exact location were determined by geomorphological condition and flow duration characteristics. Flow duration characteristics and its duration curve were identified using monthly rainfall data in Gumi STP. Relevant facts of small hydro-power system in other STP were referred to adopt to Gumi STP situation. Flowrate of treated effluents and effective head between flow chamber and the location of hydraulic turbine in Gumi STP are found to be $3.70m^3$/sec and 3.5m respectively. Electric generation rate based on this feasibility study was estimated to be 86.3kW/h. Yearly electric generation rate was expected to be 932.4MMh. Proposed small hydro-power plant construction in Gumi STP is to be reasonable.

• Water Engineering Research
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• v.2 no.1
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• pp.11-19
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• 2001

A performance prediction model for Small Hydro Power(SHP) sites has been studied and developed. Twelve SHP sites were selected and the performance characteristics were analyzed by using the developed model. Also, primary design specifications such as design flowrate, plant capacity, operational rate were suggested and feasibility for small hydro power sites were estimated. It was found that the design flowrate is most important parameter to exploit SHP plant and the methodology developed in this study can be a useful tool to analyze the performance of SHP sites.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2008.05a
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• pp.281-282
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• 2008

• Journal of Wetlands Research
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• v.11 no.2
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• pp.39-46
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• 2009

Garolim Bay is typically a semi-enclosed bay without a significant supply of freshwater and sediments from surrounding drainage area. The bay have a variety of subenvironments including deep tidal channels, tidal flats, sand dunes, islands, and inlet. Because environmental quality of bay strongly depends on the exchange of water over benthic subenvironments, it is necessary to analyze quantitatively exchange of water between sea and bay. Hydro-hypsography is the relative distribution of water-surface areas at different depths. The hydro-hypsographic curve in Garolim bay shows that the tidal flats occupy about 77 % of the bay surface. Hydraulic turn-over time (HTT) is 1.32 tidal cycles which indicate well-flushed bay. Hydro-hypsometric techniques will be useful for assessments of health of bays.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.206.1-206.1
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• 2011

Recently, various developments in the area of small hydropower have being made and small hydro turbines are suitable for domestic use because it is a clean and renewable energy source. A small hydropower generator produces power by using the different water pressure levels in pipe lines and energy which was initially wasted by use of a reducing valve at the end of the pipeline is instead collected by a tubular-type hydro turbine in the generator. In this study, in order to acquire the performance of tubular-type hydro turbine applied, the output power, head, efficiency characteristics due to the different guide vane and runner vane angle are examined in detail. Moreover, influences of pressure and velocity distributions with the variation of guide vane and runner vane angle on turbine performance are investigated by using a commercial CFD code.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.37.1-37.1
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• 2011

A floating wind turbine dynamic simulation program, 'WindHydro', is newly developed. In order to investigate the characteristics of the program, a series of loading cases are simulated such as (1) wind only case, (2) free decay cases with initial displacement, (3) wave only case (4) wind and wave case. The simulations are carried out for the 5-MW OC3-Hywind model which has a spar buoy and catenary mooring lines. As a result, the reliability of WindHydro is verified in most viewpoints although additional study is still necessary to clear out some uncertainty of the program.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.134-137
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• 2008

A methodology to evaluate the performance analysis for small hydropower at existing water treatment facilities has been studied. It consists of two main parts; flow duration function which can describe existing water treatment facilities and performance analysis to estimate the output characteristics of small hydro power plants. The output performance characteristics for Mi-ho reservoir, Sum-kang low dam, Sun-cheon sewage treatment plant and Nam-dong purification plant were analyzed, using developed model. According to the simulation results, the predicted data show that the data were in good agreement with measured results. Also, it was found that the developed model in this study can be used to analyze the output characteristics for small hydro power at existing water treatment facilities.