• 조명전기설비학회논문지
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• 제19권5호
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• pp.87-93
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• 2005

본 논문에서는 고농도$\cdot$고수율 오존발생기를 개발할 목적으로 망사형 내부전극과 무성방전의 중첩을 이용한 중첩방전형 오존발생기를 설계$\cdot$제작하였다. 중첩방전형 오존발생기는 방전공간에 3개의 전극(중심전극, 내부전극 및 외부전극)과 2개의 gap(중심전극과 내부전극 사이의 gap과 내부전극과 외부전극 사이의 gap)으로 구성되어있다. 중첩방전형 오존발생기의 중심전극을 공통접지하고 내부전극과 외부전극에 $180{[^\circ]}$의 위상차를 가진 역극성의 교류 고전압을 각각 인가하면 각각의 방전 gap에서 발생하는 무성방전이 중첩되면서 오존이 발생된다. 이때, 내부전극의 조밀도가 증가할수록 방전전극의 면적이 확대되고 방전공간의 전력밀도가 억제되어 오존생성특성이 상승하였다. 그 결과 최대 17,720[ppm], 5.4[g/h] 및 250[g/kwh]의 오존을 얻을 수 있었다.

• 한국전기전자재료학회논문지
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• 제14권11호
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• pp.898-903
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• 2001

In this study, we investigated amounts, distributions and sizes of pores of multilayer piezoelectric transformer, and predicted heat emission property and electrical characteristics according to designs of internal electrode. Forming densities of device having MLC, fingered and full filled internal electrode structure were 4.73 g/㎤, 4.80 g/㎤, 4.82 g/㎤ and forming porosities were 17.3737%, 13.1475%, 12.6121%, respectively. And sintered densities of MLC structured, fingered and full filled devices were 7.76 g/㎤, 7.75 g/㎤, 7.84 g/㎤ and sintered porosities were 4.0967%, 2.7132%, 2.5317%, respectively. Therefore, we concluded that fingered and full fi1led internal electrode devices, expecially, fingered internal electrode devices had cost-effective effect and maximum poling effect due to higher sintered density and lower porosity than MLC structured device. Also we can predict that they have an effect on good heat emission and high output properties of multilayer piezoelectric transformer.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권7호
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• pp.533-541
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• 1999

Multi-discharge type ozonizer(MDO) using superposed silent discharge has been designed and manufactured. It consists of three electrodes( central electrode, internal electrode, and external electrode ) and double gaps( gap between central electrode and internal electrode, gap between internal electrode and external electrode ). Therefore, ozone is generated by superposing silent discharges generated between the gaps respectively. And the MDO consists of three types of superposed discharge ozonizers according to voltage appling method for each electrode ; A.C. high voltages are applied two of three electrodes with phase difference of 180[˚], the other electrode is a ground. This paper describes that discharge and ozone generation characteristics of MDO which comprising central electrode and internal electrode applied A.C. high voltages with phase difference of 180[˚] respectively, and the grounded external electrode. As a result, the maximum ozone concentration, generation, and yield can be obtained 10208[ppm], 6.4[g/h], and 280[g/kwh] respectively.

• 전기학회논문지P
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• 제63권3호
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• pp.212-217
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• 2014

The electric power output characteristics of magnesium fuel cell were investigated with regard to internal resistance. A equivalent circuit with the series-connected three internal resistance was introduced to analyze of the response to change of power. The power output analysis was employed in order to investigate the effect of internal resistances for the electrolyte concentration, air electrode area, Mg electrode area and distance between the electrodes. It was confirmed that internal resistance is generated by the electrolyte, air electrode and metal electrode, then those Internal resistances had a significant effect on the power output decrease. The power output was a maximum when the load resistance maches the internal resistance of the magnesium fuel cell. The fuel efficiency was only 50% at maximum power output. Higher fuel efficiency was achieved when the load resistance is greater than the internal resistance.

• 한국세라믹학회지
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• 제35권11호
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• pp.1121-1129
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• 1998

Reactions between Ag-Pd internal electrode materials and{{{{ { {Bi }_{2 }O }_{3 } }} in multilayer chip varistor were in-vestigated. For more than 1 mol%{{{{ { {Bi }_{2 }O }_{3 } }} in varistor composition internal electrode structure was destroyed due to the reaction between internal electrode and{{{{ { {Bi }_{2 }O }_{3 } }} But for typical varistor compositions (below 1 mol% of{{{{ { {Bi }_{2 }O }_{3 } }} content) microstructural changes around the internal electrode were not observed. However SEM-EDS and TEM-EDS analysis showed the uneven distribution of{{{{ { {Bi }_{2 }O }_{3 } }} in the internal electrode which was due to the migration of{{{{ { {Bi }_{2 }O }_{3 } }} to the electorde during sintering. As a results the nonlinear coefficient of multilayer varistor showed very large distribution as well as the breakdown voltage.

• 한국전기전자재료학회논문지
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• 제15권10호
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• pp.896-901
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• 2002

The polarization and strain behavior of multilayer ceramic actuators fabricated by tape casting using a PNN-PZT ceramics were investigated in association with electrode size and internal layer number. Spontaneous polarization and strain decreased with increasing electrode size. In addition, the increase of internal layer number brought reduced spontaneous polarization and increased the field-induced strain. Because the actuators structure is designed to stack ceramic layer and electrode layer alternatively, the ceramic-electrode interfaces may act as a resistance to motion of domain wall. To analyze the effect of ceramic-electrode interface, the diffraction intensity ratio of (002) to (200) planes was calculated from X-ray diffraction patterns of samples subjected to a voltage of 200 V. The diffraction intensity ratio of (002) to (200) planes was decreased with increasing electrode size and internal layer number. The diffraction intensity ratio and straining behavior analyses indicate that the Polarization and strain were affected by the amount of 90°domain decreasing with increasing electrode size and internal layer number. Consequently, the change of polarization and displacement with respect to electrode size and layer number is likely to be caused by readiness of the domain wall movement around the interface.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2259-2261
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• 1999

In this paper, an ozonizer, which can generate individual and superposed silent discharge, using three-phase voltage has been designed and manufactured. The ozonizer consists of 3 electrodes(Central Electrode, Internal Electrode and External Electrode) and 2 gaps(gap between Central Electrode and Internal Electrode, gap between Internal Electrode and External Electrode). Ozone is generated according to voltage supplying method to each electrode by individual silent discharge and three-phase superposed discharge. The characteristics of ozone generation were investigated with variation of discharge power and the quantity of supplied gas($O_2$). In case of individual silent discharge, the maximum values of ozone concentration, ozone generation and ozone yield were obtained between internal electrode and external electrode, and its values were 2300[ppm], 570[mg/h] and 745[g/kWh] respectively. Each maximum values was 5039[ppm], 1773[mg/h] and 851[g/kWh] respectively, when three-phase superposed silent discharge was employed. Therefore, characteristics of ozone generation with three-phase voltage are improved compared with single-phase voltage because silent discharge is generated continuously.

• 조명전기설비학회논문지
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• 제19권5호
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• pp.60-67
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• 2005

본 논문에서는 진공방전관을 이용한 고농도 중첩방전형 오존발생기를 설계$\cdot$제작하였다. 3개의 전극(중심전극, 내부전극 및 외부전극)과 1개의 방전간극(내부전극과 외부전극 사이의 방전간극)으로 구성된 중첩방전형 오존발생기는 진공방전관내에 장착한 중심전극과 내부전극에 $180{[^\circ]}$의 위상차를 가진 2개의 교류고전압을 인가하고 외부전극을 공통접지함으로써 중심전극과 외부전극사이에서 발생되는 무성방전과 내부전극과 외부전극사이에서 발생되는 무성방전이 방전간극에서 중첩되는 구조이다. 이때 방전관의 진공도, 방전전력 및 산소원료가스 유량 변화에 따른 방전특성과 오존생성특성을 연구검토한 결과 최대 8840[ppm]의 고농도 오존을 얻을 수 있었다.

• 조명전기설비학회논문지
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• 제14권2호
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• pp.59-67
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• 2000

본 논문에서는 단목무성방전과 3상 전압을 사용한 중첩무성방전을 인가할 수 있는 오존발생기를 설계.제작하였다. 오존발생기는 3개의 전극(중심천극, 내부천극 및 외부전극)과 2개의 방전갭(중심전극과 내부전극 사이의 갭 및 내부전극과 외부전극 사이의 갭)으로 구성되어 있으며, 단목무성방전과 3상 중접방전이 인가되는 방식에 따라 오존화 가스가 생성된다. 이때 방전전력과 원료가스($O_2$)의 유량의 변화에 따른 오존생성특성을 연구한 결과, 단독무성방전의 경우, 최대 2300[ppm], 570[mg/h] 및 745[g/kWh]의 오존생성특성을 얻을 수 있었으며,3상 전압을 인가한 경우에는 5039[ppm], 1773[mg/h] 및 851[g/kWh]을 각각 얻을 수 있었다. 따라서 3상 중첩무성방전 이 단독무성방전에 비하여 오존생성특성올 향상시킬 수 있음을 확인하였다.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2003년도 학술대회논문집
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• pp.387-391
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• 2003

In this paper, a double cylindrical type superposed silent discharge type ozonizer which internal electrode can be produced a vacuum has been designed and manufactured Discharge and ozone generation characteristics have been investigated in accordance with output voltage of power supply, flow-rate, discharge power and vacuum of internal electrode.