• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.1190-1192
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• 2002

These days, electromagnetic radiation noise and switching losses of static converter become harmful. Many resonant inverters with radiation techniques solve their such problems. Auxiliary Resonant Commutated Pole Inverter (ARCP) was proposed. but it has two demerits. In circuit configuration. It isn't constructed by 2 in 1 IGET modules. Besides, control is complicated because of neutral point voltage control and boost current control. This paper proposes a new auxiliary resonant inverter which solved two demerits. In addition, it deals efficiency which compared with hard switching inverter and result of separation of power loss

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 추계학술대회 논문집 학회본부
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• pp.164-166
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• 1991

This paper achieved by Pulse-Withed Modulation of the inverter switchs. But Conventional PWM inverter is employed hard switching by means a switching device. Moreover, this paper presents resonant DC link Voltage type inverter thet it was not necessary snubber circuit and dead time and modeling of motor drive control system and simulating analysis are discussed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.523-525
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• 2004

Over the last few years, the control of bipedal robot has been considered a promising research field in the community of robotics. But the problems we encounter make the control of a bipedal robot a hard task. The complicated link connection of the bipedal robot makes it impossible to achieve its exact model. In addition, the joint velocity is needed to accomplish good control performance. In this paper a control method using ANFIS as an system approximator is purposed. First a model biped robot of a biped robot with switching leg influence is presented. Unlike classical method, ANFIS approximation error estimator is inserted in the system for tuning the ANFIS. In the entire system, only ANFIS is used to approximate the uncertain system. ANFIS tuning rule is given combining the observation error, control error and ANFIS approximation error. But this needs velocity information which is not available. So a practical method is newly presented. Finally, computer simulation results is presented to show this control method has good position tracking performance and robustness without need for leg switching acknowledgement.

• 경영과학
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• 제12권2호
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• pp.43-62
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• 1995

For a complex scheduling system like time table construction, its optimal solution, if exists, is hard to obtain. In this paper, the scheduling environment is reasonably confined as where objects have their own events competing for better slots on boards, and objects have their own board slot preferences and belong to one or more classes of the society which globally constrains them. Here, two phase method is suggested, where the first phase is human-like preference driven and the second phase is for fine tuning by considering all the factors given. Designed and implemented in our system HI-SCHED are dynamic object switching, temporal-constraint-driven intelligent backtracking, case-based revisions, object-based approach, and so on. Some satisfaction degrees are also defined to measure the usefulness of our method. In addition, look-ahead dynamic object switching is considered, and additional global constraints are introduced and processed. A simple scheme is also used to verify the usefulness of the post processing scheme.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.168-171
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• 2005

The conception of the passive lossless snubber with the simpler is presented. Thus a necessity condition of the passive lossless soft switching converter with the simplest topology is directed. A novel passive regenerative snubber called soft snubber applied to a hard switching converter is proposed. The passive snubber consists of a snubber inductor, two snubber rectifiers, and a snubber capacitor. The losses are reduced by inserting a snubber inductor in the series path of the rectifier during it's turn off. It is so simple that can make energy reset or capacitor discharged directly without producing any current circulation. To show the superiority of this converter is verified through the experiment with a 640W, 100kHz prototype converter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.172-175
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• 2005

Recently international regulations governing the amount of harmonic currents(e.g IEC 61000-3-2) became mandatory and active Power factor correction (PFC) pre-regulator circuit became inevitable for the AC/DC converters. Among these topologies, the boost topology represents an optimum solution for a PFC pre-regulation in a high power application. This paper propose improved ZVT(Zero Voltage Transition) AC/DC PFC Boost using the average current control employing a soft-switching technique of the auxiliary switch with a minimum number of components. The conventional ZVT PFC Boost Converter has a disadvantage that the auxiliary switch turns off hard, which influences the overall efficiency and the EMI problem. In this paper, an improved ZVT PFC Boost converter using active snubber is proposed to minimize the switching loss of the auxiliary. The prototype of 100kHz, 640W system was implemented to show the improved performance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 학술대회 논문집 전문대학교육위원
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• pp.9-11
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• 2002

These days, electromagnetic radiation noise and switching losses of static converter become harmful. Many resonant inverters with radiation techniques solve their such problems. Auxiliary Resonant Commutated Pole Inverter (ARCP) was proposed. but it has two demerits. In circuit configuration. It isn't constructed by 2 in 1 IGBT modules, Besides, control is complicated because of neutral point voltage control and boost. current control. This paper proposes a new auxiliary resonant inverter which solved two demerits. In addition, it deals efficiency which compared with hard switching inverter and result of separation of power loss

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.1847-1849
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• 2005

Unclamped Inductive Switching (UIS) 능력을 향상시키기 위하여 Floating p- well을 적용한 IGBT의 단락 회로 상태에서 과전압을 감지하는 새로운 보호회로를 제안하고 제작하였다. 실험 결과 제안된 회로는 fault 상황에서 fault 신호를 감지하고 즉시 게이트 전압을 낮추어 컬렉터 전류를 감소시켰다. 또한 Hard Switching Fault (HSF)와 Fault Under Load (FUL) 상황에서의 측정 및 2차원 Mixed-Mode 시뮬레이션을 통해 제안된 회로와 소자의 동작을 확인하였다.

• 한국통신학회논문지
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• 제22권12호
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• pp.2828-2833
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• 1997

본 논문에서는 시분할 다중화와 파장분할 다중화방식이 혼합된 광 ATM 스위치의 구조를 제안하였다. 제안된 구조의 광 ATM 스위치는 파장분할 다중화를 위한 도파로일 격자와 시분할 다중화를 위한 광압축기와 광파이버 지연선의 기본적인 모듈로 구성되어 있다. 다른 교환기 구조와 비교해 볼 때 제안된 스위치 구조는 하드웨어적으로 간단하고, 비용면에서도 매우 유리할 뿐더러 대 용량의 정보교환도 가능하기 때문에 광대역 종합정보통신망에 적합한 스위칭 시스템이다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2014년도 전력전자학술대회 논문집
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• pp.93-94
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• 2014

Recently, According to increase of power demand, it was increased a demand that switching power supply have characteristic of low-loss and high-efficiency. So increase of using device, the failure rate increases and service life problem arises. Even though normal circuit protection is applied in designing stage, it is often hard to identify the cause of malfunction in certain cases such as fatigued power supply due to over-running, malfunctions of main elements or over heating. This report will cover experimental results with the prototype we made, that monitors the efficiency of switching power supply and that protects a circuit when it drops below the standard value.