• 전기의세계
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• 제28권1호
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• pp.67-72
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• 1979

The most difficult problem encountered in the DC Chopper is the improvement in it's output waveforms and the commutation failure. Thus, this paper deals with the Load Insensitive DC Chopper that produces a quasi-pure square wave over the entire load range, and doesn't fail the commutation. The authors compared voltage and current waveforms from the laboratory model with those from the computer simulation, and it's characteristics is discussed.

• 대한전기학회논문지
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• 제38권3호
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• pp.166-172
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• 1989

The model reference adaptive control algorithm (MRAC), which is one of the methods for controlling the speed of a permanent magnet synchronous motor (PMSM), has been developed using the autoregressive (ARMAX) method. Applying this algorithm to a microprocessor which is used in driving PMSM with PI controller, it has been proved that the response speed of the reference input follows closely that of the reference model. It has also been proved by experiments that the quick speed response without over-shoot could be obtained for the motor system with variable parameters.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.101-103
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• 2001

Suspension effect has been studied by using superconductor of BiPbSrCaCuO ceramics containing Ag$_2$O It has been cleared that Ag$_2$O acts as pinning center which plays an important role to the suspension effect. Magnetic repulsive force which affects a superconductor located in magnetic flux from toroidal magnet has been investigated. It has been concluded that the suspension effect arises from the interaction between the pinning effect and the diamagnetic effect.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.489-492
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• 1997

Partial discharge characteristics of normal butyl acrylate grafted low density polyethylenes were investigated by an ultrasonic sensor made of ceramic piezoelectric material. It was found that the partial discharging activities in normal butyl acrylate grafted low density polyethylenes were considerably suppressed compared to those in plain low density polyethylene. It was found that acrylic acid grafted polyethylene was more effective than normal butyl acrylate grafted low density polyethylene.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계합동학술대회 논문집
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• pp.68-72
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• 2002

Power steering of a car plays a role that reduce driver's handle control power. Lately, it is operated using oil pressure by most engine power. However, it is tendency that electrically power steering (EPS) is used recently instead of oil pressure type more for environmental and economical reason. In this paper is SRM designed and analyzed for EPS application.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.1039-1041
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• 2003

There are many advantages of the Magnetic Bearing system, compared with conventional contacting bearing systems. Since the spindle in the Magnetic Bearing system is levitated by electro-magnetic forces and rotates without mechanical friction, it can run without lubrication. So, it can run in the extreme circumstances, e.g. a vacuum condition in the space.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
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• pp.33-35
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• 2004

The size of a PLS 300w's lighting source is smaller than the size of other's. It makes the reflector design of pls 300w more efficient. We designed it and analyzed the result of the reflector design in this paper.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.125-126
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• 2007

This paper presents a CHP Heat Exchange Mechanism considering Economic Load Dispatch with Dynamic Programming. It calculates CHP heat generation cost and Heat load pattern. Also It presents CHP optimal operation through appliance of Heat Exchange Mechanism and investigates CHP optimal operation effects about connected two regions.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2003년도 학술대회논문집
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• pp.3-8
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• 2003

Platforms of many railroad stations are crowded with passengers regardless of the time throughout day. But the intensity of illumination of the existing lightening systems are so low enough to make passengers feel inconvenience in using platforms. Consequently there exists high possibility of accidents in platforms of low illumination. Hence, for the safety and convenience of passengers, it is necessary to improve the luminous intensity of lightening system for platforms. This paper points out the problems of existing system and presents the method to improve it.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.1035-1037
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• 1993

Thermo motor that uses driving part as heating part is different from general fan heater. As it uses energy that drives rotor and generate heat at the same coil, it is simpler and cheaper than general fan heater. In this study, shaded-pole motor was used that is low cost and simple in spite of low efficiency.