• 한국방사선학회논문지
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• 제9권3호
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• pp.139-145
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• 2015

SPECT를 이용한 환자의 검사 시 몸 안에서 방출되는 ${\gamma}$-선은 감쇠 또는 산란 등의 현상이 일어나며, 검출기에 도달할 때 조준기의 물리적 특성과 기학적인 모양에 따라 퍼지는 현상이 발생하여 정량분석이 불가능하였다. 체내에서 방출되는 ${\gamma}$-선의 정확한 정량분석을 위해서는 반드시 부분용적효과에 대한 보정이 고려되어야 한다. 본 논문에서는 SPECT의 종합적인 부분용적효과를 해결하기 위하여 Sinogram Filter를 구현하였다. 구현된 Filter를 적용하여 실험을 한 결과, SPECT에서 발생되는 부분용적효과를 제거하였다. 기존방법과 제안한 방법을 비교하기 위하여 PSNR을 시행한 결과 제안한 방법으로 한 경우 PSNR은 7 dB, 기존방법은 14 dB로 나왔다. 제안한 방법의 dB이 낮아진 이유는 산란선 제거를 많이 하여 MSE가 높아지기 때문에 PSNR값이 낮게 나타났다. 따라서 제안한 방법을 적용한다면 SPECT 영상의 부분용적효과를 제거하여 영상의 질이 좋아질 것이다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.531-532
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• 2006

This paper presents our implemented, synthesized and tested on demand and partial reconfiguration approaches for FIR filters using Xilinx Virtex FPGAs. Our scope is to implement a low-power, area-efficient autonomously reconfigurable digital signal processing architecture that is tailored for the realization of arbitrary response FIR filters on Xilinx Virtex4 FPGAs. The implementation of design addresses area efficiency and flexibility allowing dynamically inserting and/or removing the partial modules to implement the partial reconfigurable FIR filters with various taps. This partial reconfigurable FIR filter design shows the configuration time improvement, good area efficiency and flexibility by using the dynamic partial reconfiguration method.

• JSTS:Journal of Semiconductor Technology and Science
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• 제4권3호
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• pp.204-209
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• 2004

A partial matched filter (PMF) for semi-coherent correlation code acquisition of the DSSS-CPFSK signal is proposed. It is a calculation-reduced structure of the hard-limited signal based FIR filter, yet its code acquisition time is equal to that of the hard-limited signal based FIR filter. The PMF eliminates duplicate calculations by utilizing the characteristic that the hard-limited DSSS-CPFSK signal has same value in several consecutive samples. For example, the PMF can achieve about 95% reduction in gate size, as compared to the hard-limited signal based FIR filter, when the modulation index of the DSSS-CPFSK signal is equal to 1.5 and the sample rate is equal to 40 sample/chip.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제12권1호
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• pp.60-65
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• 2012

This paper presents a method for occluded object based motion estimation and tracking system in dynamic image sequences using particle filter with 3D reconstruction. A unique characteristic of this study is its ability to cope with partial occlusion based continuous motion estimation using particle filter inspired from the mirror neuron system in human brain. To update a prior knowledge about the shape or motion of objects, firstly, fundamental 3D reconstruction based occlusion tracing method is applied and object landmarks are determined. And optical flow based motion vector is estimated from the movement of the landmarks. When arbitrary partial occlusions are occurred, the continuous motion of the hidden parts of object can be estimated by particle filter with optical flow. The resistance of the resulting estimation to partial occlusions enables the more accurate detection and handling of more severe occlusions.

• 전기학회논문지
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• 제59권1호
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• pp.176-183
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• 2010

This paper presents some practical design issues that should be carefully considered when a notch filter is included in a linear feedback controller. A notch filter is generally used to compensate the effects of resonant modes that may result in poor performance. It is very common that the practical engineers prefer to add such a notch filter after having previously designed a feedback controller without the filter. It is known that the resulting performance by this approach is not seriously different from when a feedback controller is designed for a plant previously compensated by a notch filter. However, we will point out that there are some cases where both approaches have different performances. In order to show this, a low-order controller design using the partial model matching method has been applied to a linear time invariant (L Tn model. The results suggest that there is a tendency to achieve much better time responses in terms of reducing the overshoot and shortening the settling time, and in the frequency domain characteristics such as the sensitivity function and the stability margins when the design of a feedback controller after including a notch filter is carried out.

• 한국의학물리학회지:의학물리
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• 제4권1호
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• pp.55-71
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• 1993

Measured and calculated the TMR and SMR factors from percent depth dose underpartial attenuators which cover the whole part of the radiation beam with variousfilter thickness from 0 to 50 mm. This study was performed for x-ray beams generated with a 6 MV linear acceleratorat source to surface distance of 100cm in a water phantom for Lipowitz metal. TMR(0,d,t) was derived from non-linear polynomial regression with field sizedifferencies and a given filter thickness. In this experiments, the TMR(0,10,50) of 50mm of filter thickness was showed13.6 % higher than that of open field and SMR(5,10,50) was 38.5% smaller than thatof open field in same depth.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권1호
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• pp.45-50
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• 1999

This paper describes a partial discharge (PD) on-line monitoring system used for large turbine generators. The system consists of a broadband current transducer, a computer-aid PD measurement system. By using a programmable fabricate band pass filter and an adaptive digital filter, the system can suppress the noise and extract PD signal from the intense noise surroundings successfully. Two simulated PD sources, which often exist in the large generators, were simulated and detected. At the end of this paper, some field test results, obtained from a 200MW generating set, were presented and discussed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.215-216
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• 2005

To decrease and remove of much noises that is detected in PD (partial discharge) measuring test. we forced on detection of those. We made W-LC filter for measuring PD. which adapted that to field test. We tested after design laboratory circumstances like field line. and then the phase change properties of detected signal in UHF sensor were measured by Lemke Probe and oscilloscope (TDS-3054. Tektronix). Eventually we checked decrement of noises from experimental result. Also from experimental result at the joint box of 22.9[kV] distribution line. we obtained reasonable data which enable noises to decrease. Hereafter those results will be adapted at ultra-high voltage for trouble prevention and on-line cable watch. diagnosis of those.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 추계학술대회 논문집 전기설비전문위원
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• pp.239-242
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• 2008

In this paper, we developed HPF (high pass filter) consisted of lumped LC components to decrease the noises that are detected in PD (partial discharge) measuring test, and adapted it to field test. We tested under laboratory circumstances like the fields, and measured the phase change properties of detected signal in UHF sensor with Lemke probe and oscilloscope (TDS-3054, Tektronix).

• E2M - 전기 전자와 첨단 소재
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• 제9권9호
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• pp.954-963
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• 1996

Particle displacement distributions of the fundamental thickness shear vibration mode and overtone modes in an energy-trapped single resonator and an energy-trapped double acoustically coupled filter were calculated. The effects of the width of a pair of partial eletrodes and the magnitude of the plate back of the resonator on the particle displacement distributions of its symmetric vibration mode and anti-symmetric vibration mode were investigated. And the effects of the width of a pair of partial eletrodes, the width of the gap between two pairs of partial electrodes and the magnitude of the plate back of the filter on the particle displacement distributions of its symmetric vibration mode and anti-symmetric vibration mode were investigated.