• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.6
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• pp.42-48
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• 2011

Generally, the structure without the stator core Axial Field Permanent Magnet (AFPM) generator was simple and there was nearly no cogging toque. And because it had the wide driving rate area, it had been being mainly used in the small wind power generation system. However, AFPM generator with non-slotted stator can't generate high voltage at low wind speed due to long air-gap. It is the reason of output efficiency drop. Therefore, in this paper, the AFPM synchronous generator with internal rotor and dual slotted stators for the small wind turbine is studied, and deal with a cogging torque minimization through the determination of optimum pole-arc ratio.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.8
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• pp.587-590
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• 2013

Release competition and development of eco-friendly vehicles have been conducted violently also automaker, it will be a high growth industry of the charger and battery, which is the driving source of the motor of an electric vehicle. Reduces the on-resistance power elements DC - DC converter for battery charger for electric vehicles, must minimize switching losses. Should have a low on-resistance power than existing products. Compare the Super Junction MOSFET and Planar MOSFET, As a result, super junction MOSFET improve on about 87.4% on-state voltage drop performance than planar MOSFET.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.469-470
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• 2007

In this paper, we propose a simple and relative electrode contact monitoring method. By exploiting the power line interference, which is regarded as one of the worst noise sources for bio-potential measurement, the relative difference in electrode impedance can be measured without a current or voltage source. Substantial benefits, including no extra circuit components, no degradation of the body potential driving circuit, and no electrical safety problem, can be achieved using this method. Furthermore, this method can be applied to multi-channel isolated bio-potential measurement systems and home health care devices under a steady measuring environment.

• The Transactions of the Korean Institute of Power Electronics
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• v.3 no.1
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• pp.46-52
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• 1998

This paper describes a current-shaping method for the production of constant torque of SRM under the nonlinear magnetic saturation condition. A current detection technique in the inductance increasing region and an approximation technique for modeling of nonlinear inductance profile are adopted. In the proposed system, a single switching angle control and voltage control is used to shape the current waveform for the generation of flat torque at any given load condition. Finally the validity of the proposed method was verified using a constructed 3HP 6/4 SRM.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.587-590
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• 2005

In this paper, the PWM inverter-motor drive system including sensor is controlled through the network. The algorithm to compensate for the time delay of ac current and ac voltage sensors due to the network is proposed. The delay time of sensors is kept nearly constant, using the synchronous signal and timers. The error between the real and estimated ac signals can be reduced by using two slopes for estimating the value of at signals. The proposed algorithms are verified with the simulation studies and experiments.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.54-56
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• 2005

The paper proposes the solar photovoltaic power generation system method for photovoltaic system to solve the power shortage due the sudden power demand. So that supplied electric power to system at appearance during surplus electric power minute and unit moment link driving with common use system is available, digital PLL circuit system voltage through composition and phase of solar photovoltatic power generation system to do synchronization do. Feed forward controller was applied to get fast current response Solar cell that is changed by solar radiation always kept the maximum output when it used Step up chopper. The dynamic character had checked through simulation used Matlab Sumulink and confirmed through an experiment.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.364-366
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• 2009

We successfully fabricated flexible electronic paper display (EPD) by using toner particles on plastic (PC) substrate. It has high resolution (WVGA : 800 ${\times}$ 480) and 7 inch diagonal viewable image size. The response time was about 0.25 msec at 90 V, a contrast ratio of about 2, a driving voltage of 60 V which we successfully demonstrated to display several images at.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.728-731
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• 2009

A negative waveform having inverted polarity of conventional waveform during reset and sustain periods was proposed to improve the driving characteristics. In order to control the negative wall-charge distribution, a positive bias on the scan electrode was applied during reset period. Compared to 0 V scan-bias condition, at 8 V scan-bias the formative time lag was improved about 23.95 % and the average time lag was improved about 14.91 %. All experiments were performed with the 42-inch PDP module in XGA resolution.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.672-676
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• 2009

Polymide is widely used alignment material of recent commercial LCD panel structure. Generally, polyimide alignment material is classified soluble polyimide type and polyamic acid type with their main bond structure of solution state. specially, compared to polyamic acid alignment layer, soluble polyimide type alignment layer have excellent reliability during long term LCD driving cause of their high imidazation ratio(%), high voltage holding ratio(%) and low ion density. The other side, this type alignment materials has significant DC image stickicng side effect for using in-plane switching mode lcd structure cause of their slow DC discharging property. we applied inorganic salt to usual soluble polyimide type alignment layer and found out this technique had good DC image sticking property without any loss of reliability property in inplane switching LCD cell structure. This approach leads excellent DC image sticking property with maintaining high reliability property this approach confirmed improves an image sticking and a reliability simultaneously from the horizontality aligned LCD mode whose relatively bad image sticking property.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.687-690
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• 2007

OLED devices with a multilayer structure were fabricated using newly synthesized hole transport materials. We confirmed that ELM229 and ELM339, hole transport materials did not affect the electroluminescence color, and that by adopting this novel hole transport materials, OLEDs with a lower driving voltage but a higher efficiency were developed.