• 전기의세계
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• 제29권2호
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• pp.118-128
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• 1980

The properties of plasmas produced by high power glass laser were investigated with various methods of diagnostics. Electron temperature was estimated by measurement of soft X-ray, and ion temperature was estimated by measurement of the time-of-flight of ion. The measurement of incident and reflected laser light, and Schlieren and shadowgragh methods were also used. No influence of laser pulse duration on the temperature was observed in the case of durations 2, 4 and 10 nsecs. The effective heating of plasma occurred in about 2 nsec of beginning of incident laser pulse. The experimental results for fast rising laser pulse were discussed and the influence of resetime of laser pulse on the heating of plasma was described. Neutrons produced by irradiating laser beam to solid deuterium target were detected.

• 대한전기학회논문지
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• 제41권5호
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• pp.474-482
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• 1992

This paper describes the speed control system of an induction type ac servomotor drive on the vector control basis of slip frequency and constant secondary flux control for a quick torque response. The system is composed of a digital controller using a SCB-V50 microprocessor and a PWM inverter with power MOSFETs for high speed switching. And, for the measurement of actual instantaneous currents, MDCS A070-051 hall sensors are employed. The rising time of step responce by this system through the test of a 600[W] ac servomotor is 30[ms]. Overall experimental result shows that the drive performance of the system is similar to that of a separately excited armature current control of a dc motior.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 B
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• pp.348-351
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• 2000

There have been significant advances in thyratron performance in recent years. these advanced waveforms have increased the complexity and cost of drive circuits. Thyratrons can reliably switch anode voltages up to 40kV and conduct peak currents up to 10kA or more. So stable thyratron drivers are essential for reliable high voltage pulse modulators. In order to operate thyratron well, thyratron driver need high repetition rate, fast rising time and low jitter. In this paper, used power MOSFET/transformer combinations. Designed thyratron driver is satisfied requirements and experimental results are presented to confirm.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 1999년도 추계학술대회 논문집
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• pp.396-400
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• 1999

인간의 감성은 다차원적 감정으로 이루어져 있다. 본 연구는 감성의 2차원 구조를 근거로 쾌-불쾌, 각성-이완 2차원적 감성을 생리신호로 분류하고자 하였다. 20명 남녀 대학생을 참가시켜 자극을 2차원 감성자극(쾌(펜디향수), 불쾌(에탄올), 각성(싸이렌), 이완(가요))으로 정의하고, 2*2 자극제시로 감성을 유발하였다. 26명의 남녀대학생을 실험에 참가시켜 4가지 감성을 유발하여, 측정한 생리신호로는 중추신경계의 활동을 나타내는 EEG(f3, p3, f4, p4)를 측정하였으며, 자율신경계의 활동을 나타내는 ECG(lead II), GSR, SKT를 측정하였다. 각각의 측정한 신호들에 대한 t-test를 실시하여 유의성 있는 변수를 추출하였으며 추출된 변수는 EEG의 f3(beta), p3(delta, beta), f4(delta), p4(alpha), HRV의 HF, HF/LF, GSR의 rising time이었으며 2차원 감성을 분류하였다.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1996년도 추계학술대회
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• pp.18-21
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• 1996

This research is the basical experiment for designing kVp meter using the photo-conductive property of Amorphous Selenium. At first, we charged the surface with A re discharge method, and changed the formed surface potential voltage by x-raying on that surface. As a result the variations of the surface charge increased by the rising kVp, while maintaining a constant exposure time and mA. We become to know that we can apply the photoconductive property of Amorphous Selenium in designing kVp meter.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 춘계학술대회 논문집
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• pp.328-331
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• 2009

This paper presents the behaviors of transient and conventional grounding impedances of a 30m counterpoise according to the injection point of lightning impulse currents. As a result, the trend of the conventional grounding impedances measured as a function of risetime of impulse current is similar to the transient grounding impedance of counterpoise. The injection point of impulse current greatly influences on the transient grounding impedance characteristics of counterpoise. The transient grounding impedances strongly depend on the injection point and the rising time of impulse current and the soil characteristics.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2005년도 추계학술발표대회 논문집
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• pp.71-75
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• 2005

For last century, our country fast changed by development of industry but we justly looked away that cultural and natural environment that must preserve inside the change, and we sought quantitative growth. But consciousness about culture is rising now; thereby social request becomes strong that is improved cultural environment; and viewpoint is appearing which is thought heftily cultural environment of city. Important thing of them is the modern age architecture, but serious discord is happening in the current society that allows conservation and destruction of the modern age architecture. But, visible cultural asset such as the modern age architecture is value when it protected as the first time, When it was broken! , restoration or age architecture really necessary to us.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.481-484
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• 2004

A form of measured temperature distribution to estimate condition of a electrical apparatus is a absolute reference for condition of the apparatus, time rate of transition, and difference between reference and currently temperature. Because passive thermography which has not injection of external thermal stimulation shows difference of temperature being on surface of a structure and temperature difference between the structure and back ground, the result could apply only to estimation or monitor for condition of terminal relaxation and overload related with temperature rising. However, a thermal flow in active thermography is differently generated by structure and condition of surface and subsurface. This paper presents the nondestructive testing using the properties and includes the results by heat injection and cooling to the apparatus. The buried discontinuity of subsurface could be detected by these techniques.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1570-1572
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• 2005

Is changed from ground signal way to Onboard signal way serving speed elevation of railroad worldwide. Therefore, importance of Onboard signal equipment is rising. Onboard signal equipment value of first time construction important. Domestic railroad and city railroad are built without standard current. Therefore, much expense is paid in maintenance and alternate of equipment. Therefore, establish standard for devices of childhood. Therefore, can have curtailment of operational expenses and specialization of skill human strength.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 A
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• pp.209-211
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• 1995

This paper is concerned with High Frequency, High Voltage Generator for X-ray using zero-voltage soft-switching PWM DC-DC high-power converter by Resonant method, which makes the most of the parastic LC parameters of high-voltage transformer link, for diagnostic X-ray power generator. The converter circuit basically utilizes phase-shift pulse width modulated series Resonant full-bridge PWM DC-DC high-power converter operating at a constant frequency;25kHz. The converter output regulation is digitally controlled using DSP (Digital Signal Processor) for obtaining a fast rising time and adjust output voltage within a wide load range.