• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.11
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• pp.1512-1516
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• 2018

The power system and control system constantly reveals surge voltage such as switching surge of lighting devices and power conversion devices, operating and stops surge of rotating devices, charge & discharge surge, opening & closing surge of circuit breakers and the like. Such a surge voltages can cause damage or malfunction of the element such as CPU, Memory, semiconductor etc. In the industry, in order to protect the system from the surge voltage, a surge protector with low discharge starting voltage, fast response time, and low capacitance is required, and technical development research for that is ongoing. In this paper, in order to solve the problem of the existing GDT discharge tube not discharging from the transient voltage which is higher than the commercial voltage and lower than the discharge voltage of the discharge element, we have developed a discharge element having the control electrode & control circuit. The discharge element having the control electrode and the control circuit can control the discharge voltage according to the needs of the consumer and can satisfy the requirement of the discharge element and the technology of the surge protector downsizing technology and the surge protection technology. It is judged to be effective for development.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.3
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• pp.72-78
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• 1999

The frequency characteristics of surface corona discharge from the electrodes on the ceramic substrate ozonator were investigated. The frequency characteristics of dark current were compared with that of corona discharge. Switching frequency which was the fraction of resonant frequency was found to be effective for corona discharge. This is regarded to distort the electric field distribution on the discharge plate which is essential for corona discharge. The measurement showed the efficiency of 28mg/W ozone generation when the switching frequency was 1/5 of the resonant frequency.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.1
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• pp.37-43
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• 2000

In this experimental study we proposed the double dielectric barrier discharge (DDBD) reactor to produce as high an electric field as possible. The experiment are conducted for applied voltage from 15 to 20[kV], $1~4[\ell/min]$ of gas flow rate and 120[Hz] and 240[Hz] of pulse rate. Superposition discharge(SPD) generated in DDBD which combined the surface discharge with the silence discharge was the most effective to reduce the $NO_x$. In the decomposition efficiency per watt, the low pulse rate gave better efficiency than the high pulse rate. However in DeNOx rate, the high pulse rate gave better performance than the low pulse rate. $NO_x$ removal rate and efficiency increased with increasing the applied voltage in all reactors.

• Journal of Korean Critical Care Nursing
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• v.4 no.1
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• pp.25-35
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• 2011

Purpose: The purpose of this study was to evaluate the actual outcomes of early discharge program for extremely low birth weight (ELBW) infants. Methods: Medical records of 122 ELBW infants admitted in the neonatal intensive care unit from January 2000 to June 2006 and those of their 112 mothers were analyzed retrospectively. Results: After being applied early discharge program to ELBW infants' mothers, their infants' lengths of stay, gestational age and body weight at discharge, duration of completion of oral feeding, number of emergency room visits after discharge were decreased and number of breast milk feeding was increased. Conclusion: Early discharge program for ELBW infants can be an effective intervention for parents and their ELBW infants contributing to neonatal nursing practices.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.581-582
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• 2005

In order to apply the discharge plasma processing. to industrial areas, the control of the chemical reaction mechanism is necessary. The hybrid plasma reactor was designed for the effective treatment of wastewater and hazardous volatile organic substances. This plasma reactor was similar to the barrier discharge, and surface discharge on the dielectric surface was propagated to the water surface strongly for the heterogeneous chemical reaction at the interface between the working gas and the water surface. The discharge emission in this discharge reactor was mainly $N_2$ second positive band in the case of $N_2$ or air gas atmosphere, and intensities from OH radicals in Ar gas atmosphere were stronger than in $N_2$ or air gas atmosphere. From this result, it is necessary to apply Ar gas for the effective generation of OH radicals in this plasma reactor.

• Tribology and Lubricants
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• v.16 no.3
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• pp.157-165
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• 2000

A discharge free Electro-Rheological Squeeze Film Damper (ER-SFD) with predetermined-clearances at leakage ends can inherently eliminate electric discharge problems while still supplying stable leakage control. Test results show that the damping force of the slotted-ring ER-SFD is mainly affected by electric voltage, oil supply pressure, position of the damper and ratio of effective surface area of slotted-rings. As the supply voltage is larger, the amplitudes of both slotted ER-SFD and rotor are decreased at first and second critical speeds. The influence of the oil supply pressure and the effective surface area ratio was shown mainly near the first critical speed. The effective surface area ratio of slotted-rings influences the reduction of flexible rotor vibration. As a result, experimental results confirm that the slotted-ring ER-SFD satisfactorily controls the flexible rotor vibration, while eliminates the inherent electric discharge problems in conventional ER-SFDs.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.7 s.184
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• pp.122-129
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• 2006

The linear compressor has lately attracted considerable attention because of its low power consumption and excellent efficiency. For an efficient design, it is necessary to develop an analytical model of the linear compressor. The effective flow and force areas are important parameters to describe the behavior of the linear compressor, which are used to determine the mass flow rates through the valving systems and the forces on the valves, respectively. It is not easy to estimate these parameters because shapes of the valve systems of the linear compressor are so different from those of tile conventional valve systems. In this paper, we suggest method to measure experimentally the effective discharge flow and force areas of the linear compressor and analyze valve characteristic to apply the experimental results to their theoretical model.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.03a
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• pp.35-39
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• 1998

Determination of effective EDM parameters is significant to increase productivity. However, With the complexity of EDM phenomena, a universal selection method of EDM parameters has not been established yet. Moreover, No attempt has been tried before to suggest a logical method in determining essential machining parameters for effective electrical discharge machining. Peak current, one of the most significant factors in EDM, is proportional to EDM area. This paper presents a method that can be Z-map modeling from CMM data, and calculate EDM area using Z-map.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1571-1575
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• 2006

Channel form discharge which determines shape and character of a channel is named as dominant discharge. Assuming that fixed discharge flows in the fluvial plain for a long time, it is channel form discharge of a certain channel if it changes the fluvial plain into shape of the channel. Channel form discharge can be demonstrated by concept of bankfull or effective discharge. 1.01, 1.58, 2, 2.33 and 5 year flood discharge were used in order to determine channel form discharge. Each frequency discharge was determined by 80 year flood discharge by a research result conducted by Kim and Won. 1.01 year frequency discharge was selected as the most similar discharge to bankfull discharge. 1.58 year frequency discharge habitually used in Korea exceeded bankfull discharge.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1107-1111
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• 2006

Channel form discharge which determines shape and character of a channel is named as dominant discharge. Assuming that fixed discharge flows in the fluvial plain for a long time, it is channel form discharge of a certain channel if it changes the fluvial plain into shape of the channel. Channel form discharge can be demonstrated by concept of bankfull or effective discharge. 1.01, 1.58, 2, 2.33 and 5 year flood discharge were used in order to determine channel form discharge. Each frequency discharge was determined by 80 year flood discharge by a research result conducted by Kim and Won. 1.01 year frequency discharge was selected as the most similar discharge to bankfull discharge. 1.58 year frequency discharge habitually used in Korea exceeded bankfull discharge.