• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.802-804
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• 2002

An analysis of the skeleton type BLDC motor is presented. The single phase skeleton type BLDC motor consists of the stator, rotor with the permanent magnet, and drive circuit with hall sensors that detect the rotor position. The major factors for the initial starting, efficiency, and torque ripples of the skeleton type BLDC motor are the detent groove of the stator and the lead angle of the phase voltage. The performance characteristics according to the angle and height of the detent groove is analyzed. The optimum lead angles of the phase voltage with the torque ripple and motor efficiency is described using the finite element method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.25-27
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• 1996

Instantaneous thrust control of linear induction motor(LIM) is needed to control its speed and position more accurately. In the vector control of LIM, it is hard to calculate flux angle exactly because of end effects of LIM. So in this paper direct vector control method is utilized to control speed of LIM. The airgap magnetic flux angle measured by hall sensors is transferred directly into coordinate transformer. As a result, some experimental values of direct vector control using DSP are shown.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.702_703
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• 2009

Electric Power Steering(EPS) system is superior to conventional Hydraulic Power Steering(HPS) system in aspect of fuel economy and environmental concerns. The EPS system consists of torque sensor, electric motor, ECU(Electric Control Unit), gears and etc. Among the elements, the torque sensor is one of the core technologies of which output signal is used for main input of EPS controller. Usually, the torque sensor has used torsion bar to transform torsion angle into torque. The torsion angle of both ends of a torsion bar is measured by a contact variable resistor. In this paper, the sensor is accurately analyzed using 3D finite element method and its characteristics with respect to four different shapes of the stator teeth are compared. The four shapes are rectangular, triangular, trapezoidal and circular type.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.877-879
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• 2001

The switched reluctance motor (SRM) has a simple motor construction with no rotor windings. It also has simple concentrated windings on the stator windings. Thus it is expected to be a lower cost machine to manufacture than other motors. This paper has computed an optimal parameters asking for SRM drives using by PC-SRD that was programmed by T. J. E. Miller/M. Mcgilp. According to advanced angle and dwell angle, the output, efficiency, currents and torque were computed. The experiments with 8/6 SRM have tested.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.402-402
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• 2011

이번 연구에서는 DC magnetron sputtering을 이용하여 타겟의 각도 변화를 주어 각도 변화에 따른 원자의 거동분석에 대해 수행하였다. 타겟의 각도가 증가할수록 비저항이 증가하고 있으며 40도의 각도의 약 600 nm의 두께에서 $5.5{\times}10^{-4}{\Omega}cm$로 나타났으며, 가시광선 영역에서 88%의 투과도를 보이는데 이는 타겟 각도에 따라 Ar 이온으로부터 나온 입자들에 의해서 플라즈마가 형성되면서 플라즈마 산란이 발생한 것으로 보며, 특히 비저항 감소와 달리 이동도 및 농도가 감소하는 형태를 보이는데 이는 Hall 측정을 통해 알 수 있다. 타겟 각도 변화는 결정 성장 방해에 영향을 주어 결정 크기는 감소하면서 스트레스로 인한 FWHM 증가가 이를 입증해 주고 있다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.404-405
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• 2007

Tin-doped indium thin film is outstanding material among transparent Conductive Oxide (TCO) materials. ITO thin films show a low electrical resistance(<$10^{-4}\;[{\Omega}{\cdot}m]$) and high transmittance(>80%) in the visible range. ITO thin films usually have been deposited on the glass substrate. In order to apply flexible display, the substrate should have the ability to bend and be deposited without substrate heat. Also properties of ITO thin film depend on what kind of substrate. In this study, we prepared ITO thin film on the polycarbonate (PC) substrate by using Facing Target Sputtering (FTS) system. Before deposition of ITO thin film, PC substrate took plasma surface treatment. The electrical and surface properties of as-deposited thin films were investigated by Hall Effect measurement, UV/VIS spectrometer and the surface property of substrate is investigated by Contact angle measurement.

• 한국산업융합학회 논문집
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• 제3권2호
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• pp.131-139
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• 2000

Gear train in the automobile to be used for controlling gas flow in automobiles consists of spur gears with involute tooth type in multiple stages. This spur gear is designed considering to the high power transfer efficiency, bending stress and contact stress in the static and dynamic analysis. The torque has been increased simultaneously the angular velocity has been decreased through the stages after being supplied by AC synchronous motor. This apparatus is controlled by electrical devices such as the PIC microprocessor, hall sensor and other electric components. By comparing the preset data of PIC microcomputer which is supplied by external DC electric power with the value set of hall sensor which detects the rotation angle position, PIC microcomputer thus controls AC motor and gear train according to the program algorithm which includes the on-off control and PWM motor driving method. As the result of the experiment such as performance, fatigue, torque test, we can conclude that this system is superior to the same and familiar foreign systems.

• 한국진공학회지
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• 제5권1호
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• pp.54-61
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• 1996

Indium-tin oxide (ITO) films were deposited on the glass substrate by the reactive -ionized cluster beam deposition(ICBD) method. In the oxygen atmosphere, indium cluster formed through the nozzle is ionized by the electron bombardment and is accelerated to be deposited on the substrate. And tin is simultaneoulsy evaporated from the boron-nitride crucible. The chracteristics of films were examined by the X-ray photoelectron spectroscopy(XPS), glancing angle X-ray diffractrion(GXRD) and the electrical properties. were measured by 4-point-probe and Hall effect measurement system . From the XPS spectrum , it was found that indium and tin atoms combined with the oxygen to form oxide$(In_2O_3, SnO_2)$. In the case of films with high tin-concentration, the GXRD spectra show that the main $In_2O_3$ peak of (222) plane, but also sub peaks((440) peak etc.) and $SnO_2$ peaks were detected. From that results, itis concluded that the heavily dopped tin component (more than 14 at. %) disturbs to form $In_2O_3$(222) phase. Four-point-probe and Hall effect measurement show that, in the most desirable case, the transmittance of the films is more then 90% in visible range and its resistivity is $$\rho$=3.55 \times10^{-4}\Omega$cm and its mobility is $\mu$=42.8 $\textrm{cm}^2$/Vsec.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 추계학술대회
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• pp.652-654
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• 2016

본 논문에서는 FPGA를 활용하여 SVPWM (Space Vector Pulse Width Modulation)방식의 정현파 BLDC 모터 구동 로직을 설계 및 구현하였다. Hall sensor를 이용한 BLDC 모터 구동 회로는 정현파 PWM 생성회로, 데드타임 회로 및 리드 앵글 생성 회로 등으로 구성 된다. 특히 PWM 생성 회로는 SVPWM방식을 이용하여 기존 정현파 PWM 대비 선형구간이 15.5% 증가된다. 설계한 회로는 VHDL을 이용하여 모의실험 하였으며 Xilinx Spartan-6 FPGA보드를 통하여 회로의 동작 및 성능을 검증하였다. 검증 결과 모터구동 전류의 THD (Total Harmonic Distortion)은 19.32% 로 기존 정현파 구동 회로 대비 우수한 특성을 보였으며 회전자 분해능은 $1.6^{\circ}$로 정밀 제어가 가능함을 확인하였다.

• 건축역사연구
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• 제26권2호
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• pp.43-52
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• 2017

While going into troops for writing in the vignette style(小品文) in opposition to the Classical Chinese(古文), Yi Ok stopped by Songgwangsa Temple in Wanju. The things he felt during this stop were recorded in the Temple Chapter("寺觀") written in 1795. Therefore, the present dissertation evaluates the Songgwangsa Temple of the time based on this Temple Chapter. Data in the Temple Chapter draws attention to the fact that it records the layout of the temple in detail. Thus the study was able to confirm the change in layout by reviewing relevant records about repair. This reveals that the form of layout in general has been maintained although there were changes involving the relocation of the buildings and their names. Furthermore, the original Buddhist building was changed to a quarter for the monks. Also, in terms of layout after the 18th century, there are frequent name changes of the Myeongbujeon(冥府殿) and Nahanjeon(羅漢殿). After two repairs, in order to find the appearance of a Daeungjeon(Main Buddhist hall) with a two-storied structure of five bays at the front, the study evaluated the Geugnakjeon at Muryangsa Temple and the Daeungbojeon at Magoksa Temple. The evaluation revealed that the 'Jeol' used in the Temple Chapter were small pillars erected on a ridgepole just like the Geugnakjeon at Muryangsa Temple, and that the angle rafters were installed to corner bays in rectangular form. The intellectual Yi Ok left behind invaluable architectural data that reveals the Songgwangsa Temple of the 18th century.