• 전기산업
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• 제8권2호
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• pp.14-22
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• 1997

• 전기산업
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• 제7권1호
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• pp.33-42
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• 1996

• 전기산업
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• 제7권3호
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• pp.41-51
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• 1996

• 전기산업
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• 제6권3호
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• pp.22-30
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• 1995

• 보험의학회지
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• 제18권
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• pp.15-20
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• 1999

• 대한전기학회:학술대회논문집
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• 대한전기학회 1982년도 하계학술회의강연논문초록집
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• pp.28-31
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• 1982

• 대한전기학회논문지
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• 제37권8호
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• pp.534-539
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• 1988

The dynamic chatacteristics and stability including steady state characteristic of the currentfed DC-to-DC converter with multiouput, which has a considerable advantage about the multioutut circuit,are analyzed in this paper. It is performed by using the steady state averaging method. As result, we know that the error, which is caused by secondary winding resistance of the transformer, exists between the two outputs in the steady state characteristics. Furthemore, it is verified that the current-fed DC-to-DC converter has also excellent stability in the multioutput application.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
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• pp.530-533
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• 1987

In high-frequency switched mode converters, Series Resonant Converter (SRC) is investigated using state-plane method. Phase plane trajectories of the SRC permit a direct closed form solution of the steady state operation and can make problems easy to solve. This paper describes steady state responses and characteristics of the SRC with respect to various circuit factors. The magnitute of steady state response and the average current through load are clearly related to how such the switching frequency differs from the resonant frequency. The results of the steady state analysis can be used to estimate the device and component stress on the power circuit.

• 한국안전학회지
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• 제3권1호
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• pp.21-29
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• 1988

Conventional pwm switching power supply have the disadvantage some aspects of size, light weight, noise and system stability. High frequency Series Resonant Converter (SRC), described in this paper, almost improve above disadvantages. We use the state plane technique as analysis method. This technique is powerful tool which can clearly analyze the peak stress of the state variables inside the converter, Here, we can define each operation mode from frequency ratio Fsn, switching frequency to resonant frequency, and we analyze the output performance in each operation mode. To verify the theoretical analysis, we compose the actual converter, and the experimental results are compared with analysis.

• 태양에너지
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• 제19권2호
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• pp.37-44
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• 1999

Experimental investigation has been carried out to determine drag reducing effects of polymer additives for a plate type heat exchanger(evaporator or condenser) in OTEC power plant applications, where the pressure drop in the heat exchangers takes up $70{\sim}80%$ of the total pumping power in the existing system. The rate of drag reduction was investigated with various polymer concentrations and mass flow rates. Experiments were undertaken for a test section in Alfa-Laval plate heat exchanger utilizing Poly Ethylene Oxide(Mw $5{\times}10^6$) as polymer additives. Concentrations of polymer additives were 5, 10, 20, 30, 40, 50, 100, 200, 400 wppm at $25^{\circ}C$ and mass flow rates were 0.6kg/s, 0.7kg/s, 0.8kg/s and 0.9kg/s in normal operating ranges for a 15kW Alfa-Laval plate heat exchanger. The maximum effects of drag reductions were found at approximately 0.7kg/s of mass flow rate. The results show that there exists the optimum mass flow rate for the plate heat exchanger to obtain maximum drag reductions. Drag reduction of 20% means considerable savings in pumping power for a large size of OTEC plant.