• The Korean Journal of Physiology and Pharmacology
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• 제16권2호
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• pp.139-144
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• 2012

It has been reported that activation of metabotropic glutamate receptor 1 (mGluR1) can mediate endocannabinoid-induced short-term depression of synaptic transmission in cerebellar parallel fiber (PF)-Purkinje cell (PC) synapse. mGluR1 has signaling pathways involved in intracellular calcium increase which may contribute to endocannabinoid release. Two major mGluR1-evoked calcium signaling pathways are known: (1) slow-kinetic inward current carried by transient receptor potential canonical (TRPC) channel which is permeable to $Ca^{2+}$; (2) $IP_3$-induced calcium release from intracellular calcium store. However, it is unclear how much each calcium source contributes to endocannabinoid signaling. Here, we investigated whether calcium influx through mGluR1-evoked TRPC channel contributes to endocannabinoid signaling in cerebellar Purkinje cells. At first, we applied SKF96365 to inhibit TRPC, which blocked endocannabinoid-induced short-term depression completely. However, an alternative TRP channel inhibitor, BTP2 did not affect endocannabinoid-induced short-term depression although it blocked mGluR1-evoked TRPC currents. Endocannabinoid signaling occurred normally even though the TRPC current was mostly blocked by BTP2. Our data imply that TRPC current does not play an important role in endocannabinoid signaling. We also suggest precaution in applying SKF96365 to inhibit TRP channels and propose BTP2 as an alternative TRPC inhibitor.

• 전기학회논문지
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• 제60권2호
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• pp.301-308
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• 2011

This paper deals with the coupled electromagnetic-mechanical field analysis for short-circuit electromagnetic force of the dry-type transformer. The short-circuit currents are calculated using external circuit in accordance with short-circuit test equipment. According to short-circuit current, the generated magnetic leakage flux density in dry-type transformer model is calculated by finite element method. The radially-directed electromagnetic forces in windings are calculated using electromagnetic field analysis and then axially-directed electromagnetic forces in windings are calculated using electromagnetic-mechanical field analysis. The calculated axially-directed electromagnetic forces in high voltage winding are compared to those of measured ones and showed good agreement with experimental results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.915-916
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• 2007

There are many equipments for the Short Circuit Test, for example Short Circuit Generator, Induction Motor, Sequence Timer, Exciter, CLR, Back Up Breaker, Making Switch and TRV etc. Especially Back up Breaker and Making Switch are very important equipments to test the short circuit test. A role of a Back up Breaker is to break high-voltage and high-current for short circuit test and a Making Switch should be operated always same speed/time and kept electrical-mechanical characteristics to make the voltage and current of short circuit test. This study introduces to the short circuit test also to kinds, principal movements and compare them of Back up Breaker and Making Switch.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.695-696
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• 2006

The inrush current of transformer cause saturation effects of recovery voltage for short-circuit power testing. the inrush current depends on the residual flux of the transformer core. when inrush current occurs, it is contains a d.c. component and the high harmonic content of the current are of importance to relay protection of testing circuit. this paper describes of decrease method of inrush current for high power short-circuit testing transformer.

• 한국정보통신학회논문지
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• 제20권5호
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• pp.992-997
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• 2016

본 논문에서는 단채널 비대칭 이중게이트 MOSFET의 상하단 산화막 두께비에 대한 터널링 전류의 변화에 대하여 분석하고자 한다. 채널길이가 5 nm까지 감소하면 차단전류에서 터널링 전류의 비율이 크게 증가하게 된다. 이와 같은 단채널효과는 상하단 게이트 산화막 구조를 달리 제작할 수 있는 비대칭 이중게이트 MOSFET에서도 발생하고 있다. 본 논문에서는 상하단 게이트 산화막 두께비 변화에 대하여 차단전류 중에 터널링 전류의 비율 변화를 채널길이, 채널두께, 도핑농도 및 상하단 게이트 전압을 파라미터로 계산함으로써 단채널에서 발생하는 터널링 전류의 영향을 관찰하고자 한다. 이를 위하여 포아송방정식으로부터 해석학적 전위분포를 구하였으며 WKB(Wentzel-Kramers-Brillouin)근사를 이용하여 터널링 전류를 구하였다. 결과적으로 단채널 비대칭 이중게이트 MOSFET에서는 상하단 산화막 두께비에 의하여 터널링 전류가 크게 변화하는 것을 알 수 있었다. 특히 채널길이, 채널두께, 도핑농도 및 상하단 게이트 전압 등의 파라미터에 따라 매우 큰 변화를 보이고 있었다.

• Journal of Power Electronics
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• 제16권1호
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• pp.362-373
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• 2016

The on-line measurement of high-power IGBT collector current is important for the hierarchical control and short-circuit and overcurrent protection of its driver and the sensorless control of the converter. The conventional on-line measurement methods for IGBT collector current are not suitable for engineering measurement due to their large-size, high-cost, low-efficiency sensors, current transformers or dividers, etc. Based on the gate driver, this paper has proposed a current measuring circuit for IGBT collector current. The circuit is used to conduct non-intervention on-line measurement of IGBT collector current by detecting the voltage drop of the IGBT power emitter and the auxiliary emitter terminals. A theoretical analysis verifies the feasibility of this circuit. The circuit adopts an operational amplifier for impedance isolation to prevent the measuring circuit from affecting the dynamic performance of the IGBT. Due to using the scheme for integration first and amplification afterwards, the difficult problem of achieving high accuracy in the transient-state and on-state measurement of the voltage between the terminals of IGBT power emitter and the auxiliary emitter (u_Ee) has been solved. This is impossible for a conventional detector. On this basis, the adoption of a two-stage operational amplifier can better meet the requirements of high bandwidth measurement under the conditions of a small signal with a large gain. Finally, various experiments have been carried out under the conditions of several typical loads (resistance-inductance load, resistance load and inductance load), different IGBT junction temperatures, soft short-circuits and hard short-circuits for the on-line measurement of IGBT collector current. This is aided by the capacitor voltage which is the integration result of the voltage uEe. The results show that the proposed method of measuring IGBT collector current is feasible and effective.

• Transactions on Electrical and Electronic Materials
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• 제17권5호
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• pp.270-274
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• 2016

This article investigates the use of the Gaussian-channel doping profile for the control of the short-channel effects in the double-gate MOSFET whereby a two-dimensional (2D) quantum simulation was used. The simulations were completed through a self-consistent solving of the 2D Poisson equation and the Schrodinger equation within the non-equilibrium Green’s function (NEGF) formalism. The impacts of the p-type-channel Gaussian-doping profile parameters such as the peak doping concentration and the straggle parameter were studied in terms of the drain current, on-current, off-current, sub-threshold swing (SS), and drain-induced barrier lowering (DIBL). The simulation results show that the short-channel effects were improved in correspondence with incremental changes of the straggle parameter and the peak doping concentration.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.608-611
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• 1989

The full-bridge series resonant converter is analyzed to limit the maximum values of the current and the voltage across resonant capacitor in the case of load short. If the converter is operated in the optimal region derived in this paper, the maximum value of short-circuit current will be smaller or equal to that of the current in steady operation. Since the additional facilities for the protection against load short do not need, converters have advantages in weight, size, and cost.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.31-33
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• 1989

In this paper, a short primary-short secondary single-sided LIM which is used as a driving source for automatic conveyor system, is selected as a analysis model. And with a method for analyzing eddy current distribution and thrust force which are produced according to the relative position of primary and secondary, FEM in which current vector potential is introduced is adopted. Also, analysis results are compared with experimental results, so propriety of this at study is proved.

• 전자공학회논문지D
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• 제34D권9호
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• pp.50-55
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• 1997

In order to improve the electrical performance of ITO/InP solar cells, sulfur passivation technique was employed using (N $H_{4}$)$_{2}$ $S_{x}$ solution. Passivation effects were analyzed by measuring the short circuit current density ( $J_{sc}$ ) of solar cells and photoluminescence (PL) of ITO/InP interfaces. This paper firstly reports the sulfur passivation effects by investigating the correlation between the PL intensity and the short circuit current. Generally, PL intensity and the short circuit current of sulfur passivated sampels wer eincreased, and showed the same trend. Especially, samples prepared at 60.deg. C (N $H_{4}$)$_{2}$ $S_{x}$ solution exhibited the highest $J_{sc}$ and PL intensity. These results demonstrated that the short circuit currents was influenced by the ITO/InP interface states.