• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.4
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• pp.183-190
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• 2003

We report the performance of an open-frame type low-voltage high-current DC-DC converter module developed using an active clamp forward converter circuit and current doubler rectifier. The converter module is designed with the specifications of an 1.8V output voltage, 25A output current, and 36-75V input voltage. The synchronous rectifier is used to reduce the conduction fuss at high current level and current-mode control is adapted to enhance the flexibility in the system configuration. A prototype converter module is successfully implemented within 10mm height and half brick size (58${\times}$61mm), and recorded an 84% efficiency and 4% voltage regulation for the entire input voltage range, thereby demonstrating its application potentials to future telecommunication electronics.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.4
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• pp.183-183
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• 2003

We report the performance of an open-frame type low-voltage high-current DC-DC converter module developed using an active clamp forward converter circuit and current doubler rectifier. The converter module is designed with the specifications of an 1.8V output voltage, 25A output current, and 36-75V input voltage. The synchronous rectifier is used to reduce the conduction fuss at high current level and current-mode control is adapted to enhance the flexibility in the system configuration. A prototype converter module is successfully implemented within 10mm height and half brick size (58×61mm), and recorded an 84% efficiency and 4% voltage regulation for the entire input voltage range, thereby demonstrating its application potentials to future telecommunication electronics.

• Proceedings of the KIEE Conference
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• 2002.11b
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• pp.274-276
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• 2002

This paper proposes a current differential relaying algorithm for power transformers using the third difference function of a differential current. The algorithm observes the instants when the wave-shape of the differential current is changed due to the change of the magnetization inductance. If the value of the third difference is bigger than the threshold, the output of a current differential relay is blocked for a cycle. In the cases of magnetic inrush and overexcitation, the blocking signal is maintained: however, for internal faults, reset in a cycle. The test results clearly show that the algorithm successfully distinguishes internal faults from magnetizing inrush.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.286-287
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• 2012

Reset-first resistive switching mechanism based on reduction reaction in HfO2-x with oxygen drift-diffusion was studied. we first report that the indirect evidence of local filamentary conductive path formation in bulk HfO2 film with local TiOx region at Ti top electrode formed during forming process and presence of anion-migration at interface between electrode and HfO2 during resistive switching through high resolution transmission electron microscopy (HRTEM), electron disperse x-ray (EDX), and electron energy loss spectroscopy (EELS) mapping. Based on forming process mechanism, we expected that redox reaction from Ti/HfO2 to TiOx/HfO2-x was responsible for an increase of initial current with increasing the post-annealing process. First-reset resistive switching in above $350^{\circ}C$ annealed Ti/HfO2 film was exhibited and the redox phenomenon from Ti/HfO2 to TiOx/HfO2-x was observed with high angle annular dark field (HAADF) - scanning transmission electron microscopy (STEM), EDX and x-ray photoelectron spectroscopy. Therefore, we demonstrated that the migration of oxygen ions at interface region under external electrical bias contributed to bipolar resistive switching behavior.

• Journal of Korean Library and Information Science Society
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• v.23
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• pp.439-469
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• 1995

The purpose of this study is to develop a new domestic (national) law classification scheme with universality. An underlying reason for the development of this scheme reset upon the fact that Civil law system, Common law system, Socialistic law system have had difficulties each other and that current classification scheme covering three law systems have not been still in existence. From the comparative discussion of classification schemes that are the representative of each law system, a new national law classification scheme with universality was designed. If law classification scheme have been completeness, this new scheme must be combined with jurisprudence and international law classification scheme which was developed already.

• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.319-322
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• 1998

In this paper we further propose to add a very simple regenerative clamping circuit to SSIPP to reduce the voltage stress and to recycle the energy trapped in the leakage inductance of the isolation transformer, thus eliminating the need for a lossy snubber circuit. In addition, this proposed clamping circuit also provides a mechanism to reset the magnetizing current of the output transformer of SSIPP employing a Forward converter as the output stage. Simulations and experimental results are reported to verify the operation and performance of the SSIPP with regenerative clamping.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.200-200
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• 2000

AC-PDP의 구동은 인가되는 Pulse의 파형에 의하여 결정된다. 이번 실험은 AC-PDP의 Subfield 파형중 Sustain 부분 첫 번째 Pulse의 폭(Width)에 변화를 주어 다음 Suatain Pulse 기간동안의 전기 광학적 특성을 구속 카메라와 전류의 변화를 통하여 측정하였으며 Sustain Pulse의 Rising Time을 변화 시켜 방전특성을 측정하였다. 이를 통하여 적합한 Sustain 구간의 초기조건을 예측하였으며, 적합한 Sustain Pulse를 찾아가는 실험 방법을 찾고자 하였다.

• Journal of the Korean Society of Safety
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• v.26 no.4
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• pp.120-126
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• 2011

Under the current law or system, the range of traffic accident on the crosswalk does not reflect the characteristics of traffic accident and the pedestrian's walking pattern. Thus, this study conducted a video recording survey on the 250 spots which are high to traffic accident rate of pedestrian-vehicle to reset the range of traffic accident on or near the crosswalk considering the characteristics of traffic accident and the pedestrian's walking pattern. Based on the collected data through a video recording survey, this study analyzed the pattern of pedestrians and extracted the variables influenced in the pedestrian's walking pattern. After conducting the regression analysis, this study made the model of measuring the range of traffic accident on the crosswalk. Through all processes these, this study reset the range of traffic accident on the crosswalk which could minimize the disadvantages of pedestrian when they have an accident on the crosswalk and ensure the right of way of pedestrian.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1391-1394
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• 2007

In this work, the discharge characteristics and temporal distribution of surface charges on the Sidoped MgO have been investigated and elucidated with the results of photon-induced surface current. Even though the Si doped MgO shows lower static voltage margin, higher luminous efficacy, and shorter statistical delay time, its discharge characteristics become deteriorated as the timing of scanning is delayed from the ramp type reset pulse down. Overall features of Si-doped MgO in discharge characteristics are well correlated with surface current characteristics.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.926-927
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• 2008

This paper presents the ZVZCS(Zero- Voltage and Zero-Current-Switching) Full-Bridge converter using the secondary coupled inductor and auxiliary capacitor. The converter with phase-shift control is proposed to reduce the circulating loss in primary and the voltage stress in secondary side. Using a coupled winding of the output inductor, two auxiliary capacitors are generated to reset the primary current at circulating interval.