• 대한전기학회논문지
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• 제36권4호
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• pp.259-266
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• 1987

In order to drive motor control system precisely, the motor is to be controlled by mmfs and current with sinusoidal waveforms. In this paper the Delta Modulation (DM) Technique is used for generating PWM pulse with sinusoidal waveform. However the motor currents yet contain odd harmonics due to leakage inductances, speed and exitation. To reduce harmonics, the parameter adaptive control method is introduced. That is, Req.C parameter of Delta Modulator is controlled adaptively by parameter adaptor. The adaptive signal is achieved by the difference between motor current and reference waveform, and this signal is converted to the voltage commend signal by adaptive mechanism. The test reslts show that this system is operated smoothly over a wide range of motor speed and motor current is controlled to be sinusoidal waveform adaptively.

• 대한전기학회논문지:전력기술부문A
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• 제54권3호
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• pp.122-132
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• 2005

This paper presents a novel approach based on Prony method to analysis of small signal stability in power system. Prony method is a valuable tool in identifying transfer function and estimating the modal parameter of power system oscillation from measured or computed discrete time signal. This paper define the relative residue of time signal and propose the condition to select low frequency oscillation in each generator. This paper describes the application results of proposed algorithm with respect to KEPCO systems. Simulation results show that the proposed algorithm can be used as another tools of power systems analysis.

• 품질경영학회지
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• 제26권2호
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• pp.17-26
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• 1998

Taguchi's parameter design is a method for quality improvement by making the performance fo a system robust to noise. Parameter design with dynamic characteristics has been recently the subject of much interest. This paper is concerned with a review and a generalization of the Signal-to-Noise (SN) ratio, a quality measure for parameter design with dynamic characteristics, proposed by Taguchi. We present a method for determination and analysis of the generalized SN ratio and illustrate its implementation by example.

• 융합신호처리학회 학술대회논문집
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• 한국신호처리시스템학회 2003년도 하계학술대회 논문집
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• pp.256-261
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• 2003

A memory industry is developing rapidly according to the period of the ubiquitous to approach. According to the development of a memory industry, the efficiency of the manufacture is becoming the serious consideration. DC parameter test system was a development low in this research for an efficiency increase of the manufacture. DC parameter test system increase of the manufacture. In the method to measure the output after permit volt and current at element.

• 한국식품저장유통학회지
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• 제16권3호
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• pp.371-375
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• 2009

ESR spectroscopy에 의한 방사선 조사 건조향신료의 조사여부의 정확한 판별에 필요한 기초자료를 얻고자 방사선 조사 유래의 cellulose radical에 대한 parameter를 분석하였다. 건조향신료 분말 4종(고추, 마늘, 양파, 후추)에 대하여 0, 1, 5, 10 kGy의 $^{60}Co$ 감마선을 조사한 후 ESR signal을 분석하였다. 방사선 조사된 4종의 건조향신료는 모두 방사선 조사 유래의 triplet signal인 cellulose radical을 나타내면서 center signal($g_2=2.00673$)은 좌우 3.0455 mT 간격의 특이적인 signal을 보였다. 조사시료에서 나타난 hyperfine triplet signal(cellulose radical)의 g-value, center field 및 저-고자장 signal의 간격은 조사선량이 변화하여도 일정하였으므로 이들 parameter들은 cellulose radical의 고유 특성임을 확인 하였다. 이로써 감마선 조사시료와 비조사 시료 간의 구별이 분명하였다. ESR signal intensity는 조사선량이 증가함에 따라 유의적으로 증가하였다($R^2=0.8452{\sim}0.9854$). 이상의 결과에서 cellulose radical의 parameter 분석은 건조향신료의 ESR 분석에서 조사여부의 판별에 대한 신뢰성을 뒷받침 해 주었다.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2003년도 10월 학술대회지
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• pp.25-28
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• 2003

The aim of this paper is to analyze the pathological voice by separating signal into periodic and aperiodic part. Separation was peformed recursively from the residual signal of voice signal. Based on initial estimation of aperiodic part of spectrum, aperiodic part is decided from the extrapolation method. Periodic part is decided by subtracting aperiodic part from the original spectrum. A parameter HNR is derived based on the separation. Parameter value statistics are compared with those of Jitter and Shimmer for normal, benign and malignant cases.

• 전자공학회논문지
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• 제51권11호
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• pp.47-53
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• 2014

레이더 신호 능동 상쇄를 위하여 기존의 MLE 기법에 비해 매우 적은 수신 신호 샘플만을 이용하여 신호의 파라미터 추정이 가능한 Pade approximation 기반의 적응적 파라미터 추정 알고리즘을 제안한다. 또한 제안하는 알고리즘이 레이더 신호의 중심 주파수를 갱신함으로써 시간에 따라 변하는 중심 주파수를 갖는 신호에 대한 능동적인 추정이 가능함을 보인다. 레이더 신호 능동 상쇄 모의실험을 통해 위협 레이더 신호의 크기에 대한 추정된 신호의 RMSE의 비를 계산함으로써 제안하는 알고리즘의 추정 정확도를 보인다.

• IEIE Transactions on Smart Processing and Computing
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• 제3권6호
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• pp.372-381
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• 2014

This study examined a radar signal active cancelation technique, which is a theoretical way of achieving stealth by employing a baseband process that involves sampling the incoming hostile radar signal, analyzing its characteristics, and generating countermeasure signals to cancel out the linear-FM signal of the hostile radar signal reflected from the airborne target. To successfully perform an active cancelation, the effects of errors in the countermeasure signal were first analyzed. To generate the countermeasure signal that requires very fast and accurate processing, the down-sampling technique with the suboptimal maximum likelihood estimation (sMLE) scheme was proposed to improve the speed of the estimation process while preserving the estimation accuracy. The simulation results showed that the proposed down-sampling technique using a 2048 FFT size yields substantial power reduction despite its small FFT size and exhibits similar performance to the sMLE scheme using the 32768 FFT size.

• Journal of Power Electronics
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• 제12권3호
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• pp.399-409
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• 2012

In DC-DC Buck converters with average current mode control, the current loop compensator provides additional design freedom to enhance the converter current loop performance. On the other hand, the current loop circuit elements append substantial amount of complexity to not only the inner current loop but also the outer voltage loop, which makes it demanding to quantify circuit and operating parameter effects on the small-signal dynamics of such converters. Despite the difficulty, it is shown in this paper that parameter effects can be analyzed satisfactorily by using an existing small-signal model in conjunction with a newly proposed simplified alternative. As a result of the study, new insight into average current mode control is uncovered and discussed quantitatively. Measurable experimental results on a prototype averaged-current-mode-controlled Buck converter are provided to facilitate the analytical study with good correlation.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
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• pp.610-621
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• 1998

In parameter design introduced by Taguchi, we analyze a signal-to-noise(SN) ratio. The SN ratio is a function of the expected loss due to the variation of quality characteristic. In this paper, an easy way for developing SN ratios is presented, which can be used to several quality characteristics simultaneously in parameter design. To develop such multivariate SN ratios, the transformation method of the expected loss and combining techniques are employed. And the analysis of real empirical data for an application of the proposed method is also presented.