• The Journal of the Acoustical Society of Korea
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• v.22 no.1E
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• pp.43-48
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• 2003

The effects of linear acoustic channels have been analyzed and compensated at mel-frequency feature domain. Unlike popular RASTA filtering our approach incorporates separate filters for each mel-frequency band, which results in better recognition performance for heavy-reverberated speeches.

• Journal of electromagnetic engineering and science
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• v.16 no.3
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• pp.191-193
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• 2016

This paper proposes a voltage-controlled oscillator (VCO) that has broadband turning and low-level of phase noise characteristics. Due to the micro-strip line resonant circuit with a low Q value, which is applied to the broadband tuning range, the depreciated phase noise performance is compensated by restraining the harmonics of the oscillating frequency. The VCO was designed according to the proposed structure as well as the conventional structure, and the superiority of the proposed structure was verified through its simulation, fabrication, and measurement.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.50-55
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• 2002

The transient numerical analysis was performed for vapor cooled current leads. The present numerical modeling considered that there is temperature difference between the copper lead and the helium vapor flow. This numerical modeling was compensated and validated by the experiment with commercially available 100 A current leads. The numerical modeling in this paper described thermal characteristics of overloaded current leads more accurately than the conventional steady state analysis. Proper design of overloaded current leads was suggested by indicating the appropriate overloading factor in the pulse mode operation.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.209-212
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• 2004

A navel fast-switching LCD with dual-domain bend (DDB) mode is described DDB alignment is achieved using antiparallel-rubbed cell filled with chiral-doped LC. Initial alignment is mono-domain 180-degree twist. Tilt direction is controlled by oblique electric field to be counter direction in each domain Twist-to-DDB deformation occurs continuously so that DDB mode does not require high-voltage initialization which is inevitable in Optically Compensated Bend (OCB) mode. DDB gives wide and symmetric viewing angle in contrast to mono-domain bend formed from 180-degree twist showing strong asymmetry.

• Proceedings of the IEEK Conference
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• 2001.09a
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• pp.371-374
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• 2001

본 논문에서는 움직임 보상을 이용한 Motion-Adaptive De-interlacing Method를 제안 한다. 정확한 움직임 추정을 위해서 Pre-filter로서 EBMF(Edge Based Median Filter)를 사용하며 새로운 Block Matching Method를 제안한다. Temporal Filter로서 Motion Missing Error를 제거하기 위해 입력 영상의 움직임 영역에 따라 각각 다른 임계 값을 적용하는 AMPDF(Adaptive Minimum Pixel Difference Filter)를 적용하였으며 MMD(Maximum Motion Detection)와 SAD(Sum of Difference)를 이용하여 빠른 움직임 영역에서 화질을 향상시켰다. 최종적으로 잘못된 움직임 보상에 기인하는 화질의 열화를 방지하기 위한 Motion Correction Filter를 제안한다.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.1247-1250
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• 1998

In speech synthesis, LF model is widely used for excitation signal for voice source coding system. But LF model does not represent the harmonic frequencies of excitation signal. We propose an effective method which use sinusoidal functions for representing the harmonics of voice source signal. The proposed method could achieve more exact voice source waveform and better synthesized speech quality than LF model.

• Journal of Technologic Dentistry
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• v.9 no.1
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• pp.79-88
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• 1987

According as the density of prosthetic by casting among the prosthetic restorations is increasing now, the definition and the bounds as to the casting, the method of making the right casting and the establishment of concepts about a minute report and so on, the establishment of the basic principles like those are unavoidable, and then the casting shrinkage must be compensated by setting expansion thermal expansion. Hygroscopic expansion in making the good casting types as we demonstrated that already asbestos lining. We confirmed the fact that the considerable concern about the surface tension and the gas inspiration? Is necessary in making better the casting.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.7
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• pp.1342-1348
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• 2009

DSTATCOM(distribution static compensator) is one of the custom power devices, and protects a distribution line from unbalanced and harmonic current caused by non-linear and unbalanced loads. Researches about DSTATCOM are mainly divided two parts, one is the calculation of compensated current and the other part is the current control. This paper proposes a proportional-resonant-repetitive current controller. Improved performance of instantaneous power compensation has been shown by simulations and experiments.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.111-114
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• 2000

Harmonics and fundamental reactive power of nonlinear loads in serious unbalanced power condition are compensated by current synchronous detection(CSD) theory which is also acceptable for single phase power system, but the CSD theory is not suitable any more in case of controlled independently harmonics and reactive component. Therefore a new algorithm the extended current synchronous detection (ECSD)theory for a three phase active power filter based on decomposition of fundamental reactive distorted components is proposed in this paper. The proposed ECSD theory is simulated and tested comparison with a few power theories under asymmtrical condition in power system.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1996.10a
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• pp.195-201
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• 1996

The dynamic characteristics of externally pressurized journal bearing have been studied theoretically. The Reynolds' equation has been solved by FDM, and the dynamic coefficients have been calculated by using perturbation method. The bearing is compensated by orifice or double-pad diaphragm control valve. The effects of diaphragm initial gap and stiffness are considered. As the results of analysis, it is shown that a control valve has better performance than orifice.