• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 학술대회 논문집
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• pp.309-313
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• 2004

This paper presents an algorithm of detecting changed intervals with step-type shape in motor's speed response data. The proposed method is composed of 4 parts such as noise filtering, decision making of reference value's change, finding entrance point of steady state and detecting changed intervals. According to simulation results for three cases, we see that changed intervals can be found well.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 추계학술대회 논문집
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• pp.21-22
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• 2012

This paper propose initial rotor position detecting algorithm of incremental encoder. The proposed algorithm estimates d-axis initial position of PMSM using 6 step operation. The proposed algorithm is verified by experimentally.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.156-160
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• 1997

This paper introdues the development of hydraulic cylinder with magnetic sensor detecting absolute and precise position for automation of excavator. The system which is developed can detect absolute position witha little displacement by using algorithm for recognizing datum points, 1/4 divider algorithm and high precision algorithm improved position precision and robustness to noise etc. The solenoid valve and PWM control using saw-toothed wave are used for absolute position control of cylinder, respectively

• 한국정밀공학회지
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• 제20권4호
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• pp.68-75
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• 2003

This paper introduces the development of hydraulic cylinder with magnetic sensors detecting absolute and precise position for automation of excavator. The system which is developed can detect absolute position with a little displacement by using algorithm for recognizing datum points, 114 divider algorithm and high precision algorithm improved position precision. We alse evaluate the developed system under the load disturbance and add band pass filter to the previous's signal process circuit for the protecting magnetic sensors's saturation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
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• pp.449-453
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• 1987

This paper presents the detecting algorithm of inrush current which causes protective equipment to maloperate in energizing a power distribution line. This detecting algorithm uses the method which extracts the decay component and energy of 2nd harmonics by Prony Spectral Estimation Method existed AR model to new ARMA model. In this paper, the inrush currents are obtained by model simulations and fild tests. By applying these data to the detecting algorithm, it has been confirmed to discriminate inrush currents from fault currents.

• 한국정보통신학회논문지
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• 제15권4호
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• pp.957-964
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• 2011

영상 안정화(image stabilization)는 흔들림이 있는 영상을 영상처리 기법으로 안정화 시키는 과정을 말한다. PA(projection algorithm)기법을 이용한 디지털 영상 안정화는 쉽게 글로벌 모션을 얻을 수 있어 많이 연구가 되어 왔다. PA기법은 실현이 간단하고 속도가 빠른 장점이 있지만 고정된 탐색범위를 사용함으로 탐색범위를 초과한 떨림을 안정화 시킬 수 없고 또한 큰 떨림을 안정화 하기위하여 탐색범위를 크게 하면 모션 추적에 참여하는 블록이 작아져 적확한 글로벌 모션을 얻지 못하게 된다. 본 논문에서는 기존의 PA기법의 단점을 해결하기 위하여 여러 가지 흔들림의 크기에 절용할 수 있는 IPA(Iterative Projection Algorithm)기법을 제안하여, 차량에서 찍은 연속된 영상 1000프레임에 적용하였을 때 기존의 알고리즘을 사용하고 서로 다른 탐색범위를 사용한 결과보다 PSNR이 최저 6.8%, 최고 28.9% 향상 되었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
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• pp.151-154
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• 2000

We propose a statically motivated scene change detection algorithm. As the difference between the neighboring frames will generate peaks at scene boundaries, the problem of detecting fast scene changes is equivalent to detecting peaks in a given sequence. In this paper, the peak detection is performed via several statistics, namely the sample means and variances. For eliminating flash lights as well as detecting fast scene changes within a small number of frames, we have opted to use a two-stage process for computing the necessary statistics. The results indicate superiority of necessary statistics. The results indicate superiority of the proposed algorithm over the previously reported algorithm.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2000년도 하계학술발표대회 논문집 제19권 1호
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• pp.439-442
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• 2000

When we measure the acoustical properties of a room using multiple microphone system, it is important to grasp exact time delay of the early reflections from impulse response pair. But it is often very difficult to identify the early reflections in natural shape, because a waveform may be deformed due to the characteristics of a sound source loudspeaker, microphone and reflected wall and overlapping of plural waveform. In this paper to obtain more accurate and enough early reflections, we propose the brand-new five-channel sound receiving system and introduce peak-detecting algorithm. The system has microphones mounted at the origin and four points of a regular tetrahedron. The newly introduced peak-detecting algorithm can show exact peak position in each channel, in spite of deformation due to reflected walls, loudspeaker and microphone.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.249-251
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• 2001

This paper presents performance analysis on a low pass filter of a CT saturation detecting algorithm using difference. At the instants of beginning/end of saturation, the shapes of the secondary current are changed significantly though secondary currents are continuous. At the instants, the second-order or third-order difference of the secondary current has big values because of discontinuity of the first order difference. Thus, the third difference of the current is used to detect the beginning/end of CT saturation. An antialiasing low pass filter removes high frequency components and causes phase lag. A CT saturation detecting algorithm using difference of CT secondary currents is affected by the low pass filter. The algorithm is tested with cutoff frequencies of the filter for the two sampling rates of 64[S/C] and 32 [S/C]. The results of various test cases indicate satisfactory performance of the algorithm.

• 환경영향평가
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• 제10권1호
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• pp.1-8
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• 2001

Detection of red tides by satellite remote sensing can be done either by detecting enhanced level of chlorophyll pigment or by detecting changes in the spectral composition of pixels. Using chlorophyll concentration, however, is not effective currently due to the facts: 1) Chlorophyll-a is a universal pigment of phytoplankton, and 2) no accurate algorithm for chlorophyll in case 2 water is available yet. Here, red band algorithm, classification and PCA (Principal Component Analysis) techniques were applied for detecting patches of Cochlodinium polykrikoides red tides which occurred in Korean waters in 1995. This dinoflagellate species appears dark red due to the characteristic pigments absorbing lights in the blue and green wavelength most effectively. In the satellite image, the brightness of red tide pixels in all the three visible bands were low making the detection difficult. Red band algorithm is not good for detecting the red tide because of reflectance of suspended sediments. For supervised classification, selecting training area was difficult, while unsupervised classification was not effective in delineating the patches from surrounding pixels. On the other hand, PCA gave a good qualitative discrimination on the distribution compared with actual observation.