• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
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• pp.283-285
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• 1987

Transient conduction current (I - t characteristics) were measured in thin PPMMA (plasma-polymerized methyl methacrylate) films over the temperature range $60^{\circ}C-140^{\circ}C$ and the applied voltage range 3V - 30V. The current, which increased with temperature rise at constant applied voltage, showed less absorption current (current decay with time) at higher temperature region compared with those at lower temperature region. And the current, which increased with applied voltage rise at the constant temperature, showed less absorption current at higher voltage compared with those at lower voltage. The electric field current density characteristic curves were abtained from the conduction current values were after applying voltage for 30 minutes. And transient conduction currents were analyzed with high field conduction theories.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.103-108
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• 2003

In this paper, the current lead for superconducting device is studied by numerical method. The current lead is cooled by surrounded $N_{2}$ gas by natural convection. The heat conduction equation for current lead and boundary layer equation for $N_{2}$ gas must be solved simultaneously. The boundary layer equation for $N_{2}$ gas is highly nonlinear for varied temperature of current lead. So the linearization method is adopted for simplicity. Numerical results using natural convection cooling are compared with the conventional cooling methods such as conduction cooling and vapor cooling methods. The main difference of natural convection cooing is the non-zero temperature gradient at the top of current lead for the minimum heat dissipation into superconducting devices. For the optimized conduction-cooling and vapor-cooling current leads, the temperature gradient at the top of current lead is zero. Also, the heat flow at the cold end is much smaller than conduction cooling case.

• 전기학회논문지
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• 제60권11호
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• pp.2049-2055
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• 2011

In this paper a new current control method is proposed for the discontinuous conduction mode of boost converter. The proposed method using a current gain feedforward compensation adjusts a measured inductor current value and then, calculated an average current precisely in the discontinuous conduction mode as well as continuous conduction mode. By applying the proposed method, the current measurement error is significantly reduced to 2% regardless of the operating points. The proposed method is analyzed and its performance is investigated in simulation. To verify the feasibility of the proposed scheme, a 10kW 3-phase interleaved boost converter was built and experimental results are matched to the simulation results.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.216-217
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• 2007

In this paper we investigated the volume resistivity and AC conduction current according to the temperature and voltage. As a result, the volume resistivity comes to be small according to the measurement temperature and voltage. AC conduction current of the heat treatment specimen is increased because of the decrease of insulation.

• 한국정보통신학회논문지
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• 제19권3호
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• pp.575-580
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• 2015

비대칭 이중게이트(double gate; DG) MOSFET는 단채널 효과를 감소시킬 수 있는 새로운 구조의 트랜지스터이다. 본 연구에서는 비대칭 DGMOSFET의 전도중심에 따른 차단전류를 분석하고자 한다. 전도중심은 채널 내 캐리어의 이동이 발생하는 상단게이트에서의 평균거리로써 상하단 게이트 산화막 두께를 달리 제작할 수 있는 비대칭 DGMOSFET에서 산화막 두께에 따라 변화하는 요소이며 상단 게이트 전압에 따른 차단전류에 영향을 미치고 있다. 전도중심을 구하고 이를 이용하여 상단 게이트 전압에 따른 차단전류를 계산함으로써 전도중심이 차단전류에 미치는 영향을 산화막 두께 및 채널길이 등을 파라미터로 분석할 것이다. 차단전류를 구하기 위하여 포아송방정식으로부터 급수 형태의 해석학적 전위분포를 유도하였다. 결과적으로 전도중심의 위치에 따라 차단전류는 크게 변화하였으며 이에 따라 문턱전압 및 문턱전압이하 스윙이 변화하는 것을 알 수 있었다.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 1997년도 추계학술대회 발표논문집:21세기를 향한 정보통신 기술의 전망
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• pp.451-462
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• 1997

A 2-dimensional numerical analysis is presented for thermal-electron heat conduction effects upon the electron transport and the drain current-voltage characteristics of submicron GaAs MESFETs, based on the use of a nonstationary hydrodynamic transport model. It is shown that for submicron GaAs MESFETs, electron heat conduction effects are significant on their internal electronic properties and also drain current-voltage characteristics. Due to electron heat conduction effects, the electron energy is greatly one-djmensionalized over the entire device region. Also, the drain current decreases continuously with increasing thermal conductivity in the saturation region of large drain voltages above 1 V. However, the opposite trend is observed in the linear region of small drain voltages below 1 V. Accordingly, for a large thermal conductivity, negative differential resistance drain current characteristics are observed with a pronounced peak of current at the drain voltage of 1 V. On the contrary, for zero thermal conductivity, a Gunn oscillation characteristic is observed at drain voltages above 2 V under a zero gate bias condition.

• 대한전기학회논문지
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• 제40권5호
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• pp.489-495
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• 1991

In this paper, we study the electrical conduction mechanism in Langmuir-Blodgett(LB) ultra thin films for which the LB device has a metal/LB films(TCNQ)/metal sandwich structure. Our experiments show that the current at the LB device does not depend on the temperature at below 0 C. This phenomena confirm that the electrical conduction current is a tunnel current inherent to ultra thin films. However, the current depends upon the temperature near the room temperature. This phenomena indicates the electeical conduction current is a Schottky current inherent to ultra thin films.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권7호
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• pp.322-327
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• 2002

Temperature-dependent current-voltage characteristics of organic light-emitting diodes(OLEDs) were studied in a device structure of ITO/TPD/Alq$_3$/Al to understand conduction mechanism. The current-voltage characteristics were measured in the temperature range of 8K ~ 300K. We analyzed an electrical conduction mechanism of the OLEDS using space-charge-limited current(SCLC) and Fowler-Nordheim tunneling. In the temperature range above 150k, the conduction mechanism could be explained by space charge limited current from the inversely proportional temperature dependence of exponent m. The characteristic trap energy is found to be about 0.15ev. At low temperatures below 150k, the Fowler-Nordheim tunneling conduction mechanism is dominant. We have obtained a zero field barrier height to be about 0.6~0.8eV.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 학술대회 논문집
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• pp.178-181
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• 2003

Intermediate cooling for current lead is used of thermal link in conduction cooling and cooled of itself in liquid cooling because it is put in liquid. If a existing formula for cooling load and optimal diameter-length of current lead is applied, it generate some more cooling load. Therefore, variation of thermal link height and holding depth in liquid is considered. This result is used of reducing cooling load of current lead occupying most of superconducting system load and applying liquid/conduction cooling systems.

• E2M - 전기 전자와 첨단 소재
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• 제8권2호
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• pp.176-183
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• 1995

The present work is concerned with the switching conduction characteristics of PI LB films in metal insulator metal sandwiches. By applying various DC voltage bias to MIM junctions, conduction characteristics of junctions can be changed between the high-voltage low-current(off) condition, the low-voltage high-current (on) condition and the medium(mid) condition. Switching conduction characteristics can be also observed in MIM junctions employing some aromatic compounds as insulators. Switching conduction characteristics is assumed to be owing to the existence of aromatic rings, space charge in films, impurities on metal-insulator interface, and difference in work functions of base and top electrodes metal. To study the conduction process of on, off, and mid conductions, we measured I-V, d$^{2}$V/d I$^{2}$-V characteristics of junctions with several different top electrodes under various temperatures. Small conductance changes of junctions can be measured by observing the second derivative, d$^{2}$V/dI$^{2}$, of I-V curve. A dynamical technique is used to get the second derivatives. That is, a finite modulation of the current is applied to the junctions and the second harmonic of the voltage is detected.