• 전자공학회논문지SC
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• 제38권2호
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• pp.38-49
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• 2001

본 논문은 IC chip내에서 전압을 낮추는 목적으로 사용되는 VDC 회로의 주파수 특성을 향상시키기 위한 새로운 회로를 제안한다. 제안된 회로에는 적응 바이어싱 방법을 통해 저전력소모 및 고속동작을 동시에 만족하는 두 개의 센서와 이 센서로 구동되는 3개의 transistor가 부가적으로 첨가되어 구동 transistor의 gate 충.방진 전류를 보상하여 구동회로의 정상동작을 유지시켜준다. 본 연구에 사용된 회로는 $0.62{\mu}m$ N well CMOS 공정을 사용하였으며, H spice simulation 결과, 내부전압의 변화폭은 부하전류가 0에서 $200m{\Lambda}$까지 5ns동안 증가할 경우 약 1.0V로, $200m{\Lambda}$에서 0으로 감소할 경우 약 0.6V로, 내부전압 회복시간은 증가시 7ns, 감소시 10ns로, 일반적인 구동방식에 비해 성능이 향상되었으며 전체 회로에 소모하는 power는 약 1.2mW로 매우 작았다.

• 전기학회논문지
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• 제56권7호
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• pp.1261-1267
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• 2007

Although LEDs have been used in various applications with improving the brightness and luminous efficacy, the electrical and optical characteristics of high power LED varies at different temperature and starting time. In this paper, optimal heat sink and apparatus design were conducted using IR camera and ICEPAK on the LED bulb consisting with fourteen LED array. The temperatures of heat sink and LED device of the designed LED bulb without cooling pan were $74^{\circ}C\;and\;96.8^{\circ}C$, respectively, showing in good themal characteristics. For high efficiency driving circuit of LED array adopted optimal heat sink design, driving circuits of constant voltage and current circuits were suggested and fabricated. As a result the efficacy of all driving circuits showed more than 20 lm/W. Also, the constant current circuits are suitable for signal lamp, hallway lamp, and flash lamp having short operating time(about 30 min). On the other hand, a reading light and indoor lamp having long operating time can be controlled by constant voltage circuit.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권3호
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• pp.111-119
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• 2005

In the magnetic fluid linear pump, the pumping forces and pumping speed mainly depend on the current patterns. In this research, a new design to reduce the discontinuities of the pumping forces of the MFLP was studied. Continuous pumping of the newly designed MFLP by using AC current increases pumping efficiency and reduces the pumping force. Forming shapes of the magnetic fluid at the intermediate state were computed and compared to measurement. Since the back flow of the fluid is reduced remarkably, 4 yoke's AC driving is more efficient than 7 yoke's DC driving. The size, weight and pumping discontinuity are also reduced.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.76-81
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• 1993

This paper presents an Auto-Drive-Guidance System which provides a path to the destination with the shortest driving distance(or time), as well as service information such as the location of gas stations, hospitals, or police stations. This system displays on the monitor screen the best driving path to the destination, points the current car position on the map, informs the driver of current position by voice whenever the car passes well-known places, or displays the map the driver wishes to view. With this system, driving becomes more comfortable, and traffic jams will be greatly reduced. As a result, gasoline consumption will be reduced and so air pollution. The system can also be applied to such areas as communication network, geographic map, and tour information.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 F
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• pp.2166-2168
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• 1998

A PWM inverter using power FET is developed to switch the excitation current of 5 phase hybrid stepping motor for the use of driving X, Y table. A micro processor based controller is also developed to control the excitation current switching of X, Y axis stepping motor as well as synchronizing operation of Z-axis servo motor. The developed driving control system is applied to the industrial embroidery sewing machine.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.887-888
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• 2006

Switched Reluctance Motor(SRM) is rotated by reluctance force generated between rotor pole and stator pole. So SRM must be switched by exciting current according to rotor position. but SRM takes the advantages of high speed driving and very simple structure. The single phase SRM can not be start by itself and torque ripple is generated more than multi-phase SRM. But mechanical structure and driver is simpler than multi-phase SRM. The single phase SRM driver is composed with the absolute encoder and DSP to control exciting section and current, and is supplied by constant voltage. So The paper is intend to measure the speed charactrer of double silent pole type SRM by using the unipolar driving curcuit.

• 산업기술연구
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• 제31권A호
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• pp.95-101
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• 2011

According to recent technological developments in high-power LEDs, the stage lighting is one of most important areas to apply power LED system. Moving light for color rendering of stage uses the RGBW(red, green, blue, white) color mixing method. LED moving light system needs to have a wide range of dimming control as enough to operate at very low power. Also LED dimming system should not be induced color-shift and flicker in camera. This paper is experimentally verified the LED Moving Light driving circuit of 200Watt level designed to satisfy the above characteristics which applied the DC current-controlled and PWM mixed dimming method.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권1호
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• pp.15-19
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• 2000

The main advantages of DSPSRM lie in the simple robust construction, low manufacturing cost and simple driving circuit. Especially, it is possible to make shortly the axial length of DSPSRM. therefore, it is suitable to setup this motor in a narrow space. For practical use, prototype of DSPSRM was already manufactured. In this paper, we explain driving method and design driving circuit of DSPSRM. And then speed, torque and efficiency are measured. As a result of measurement, the torque was constant at normal speed and the speed was linearly increased as the current increase. Therefore, we verify that DSPSRM is suitable for low-speed fan load.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권5호
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• pp.339-343
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• 1999

This paper reports the characteristics of poly-Si TFT unitary CMOS circuits fabricated with various techniques, in order to investigate the optimum process conditions. The active films were deposited by PECVD and LPCVD using $SiH_4\; and\; Si_2H_6$ as source gas, and annealed by SPC and ELA methods. The impurity doping of the oource and drain electrodes was performed by ion implantation and ion shower. In order to investigate the AC characteristics of the poly-Si TFTs processed with various methods, we have examined the current driving characteristics of the polt-Si TFT and the frequency characteristics of 23-stage CMOS ring oscillators. Ithas been observed that the circuits fabricated using $Si_2H_6$ with low-temperature process of ELA exhibit high switching speed and current driving performances, thus suitable for real application of large area electronics.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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• pp.198-200
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• 2001

In this paper, we describe the developed learning tool of expert system for preventive diagnosis of substation power equipments. The expert system was programmed by using the diagnosis methods as like gas analysis in oil and partial discharge, hottest temperature, the current of OLTC driving meter, the current of fan and pump in MTr and driving coil current in GCB and leakage current in LA. The learning tool is composed of the expert system and the explanation of diagnosed examples and the applied rules and it well worked according to the rule.