• Title/Summary/Keyword: Noise Elimination

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Dedicated hardware implementation for real time noise elimination of 2-valued image (실시간 처리를 위한 2차 화상의 잡음 제거 전용 하드웨어 구성)

  • Park, In-Jung;Lee, Dong-Chan
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.243-246
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    • 1988
  • A lot of time is required in order to the process of loop repeating the preprocessing operated in the software. Specially in the preprocessing, most of the time is used for the noise elimination such a software algorithm component of a noise elimination hardware, this can operate quickly the process.

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Transmission Matrix Noise Elimination for an Optical Disordered Medium

  • Wang, Lin;Li, Yangyan;Xin, Yu;Wang, Jue;Chen, Yanru
    • Current Optics and Photonics
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    • v.3 no.6
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    • pp.496-501
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    • 2019
  • We propose a method to eliminate the noise of a disordered medium optical transmission matrix. Gaussian noise exists whenever light passes through the medium, during the measurement of the transmission matrix and thus cannot be ignored. Experiments and comparison of noise eliminating before and after are performed to illustrate the effectiveness and advance presented by our method. After noise elimination, the results of focusing and imaging are better than the effect before noise elimination, and the measurement of the transmission matrix is more consistent with the theoretical analysis as well.

Design of a Cascade Adaptive Filter for the Performance sn Detection of Segment (ST세그먼트 검출성능향상을 종속 적응필터의 세계)

  • 박광리;이경중
    • Journal of Biomedical Engineering Research
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    • v.16 no.4
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    • pp.517-524
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    • 1995
  • This paper is a study on the design of the cascade adaptive filter (CAF) for baseline wandering elimination in order to enhance the performance of the detection of ST segments in ECG. The CAF using Least Mean Square (LMS) algorithm consists of two filters. The primary adaptive filter which has the cutoff frequency of 0.3Hz eliminates the baseline wandering in raw ECG The secondary adaptive filter removes the remnant baseline wandering which is not eliminated by the primary adaptive filter. The performance of the CAF was compared with the standard filter, the recursive filter, and the adaptive impulse correlated filter (AICF). As a result, the CAF showed a lower signal distortion than the standard filter and the AICF. Also, the CAF showed a better perf'ormance in noise elimination than the standard filter and the recursive filter. In conclusion, considering the characteristics of the noise elimination and the signal distortion, the CAF shows a better performance in the removal of the baseline wandering than the other three Otters and suggests the high performance in the detection of ST segment.

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A Study on the Development of a Resonator to Reduce the Ship Engine Room Noise (선박기관실의 소음 저감을 위한 차폐공명기의 개발에 관한 연구)

  • Yu, Y.H.
    • Journal of Power System Engineering
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    • v.11 no.4
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    • pp.72-77
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    • 2007
  • It is known that elimination of ship engine room noise is impossible thing, so the working environment in the engine room is getting worse because ships are recently built with huge engines to take higher sailing power. In the yacht and cruise yacht, the engine room noise is more serious because they have bigger engines relative to their hull sizes. The noise generated from the main engine makes the employee to hearing loss and the transmitted noise make the uncomfortable conditions in the cabins of ship. The noise generated by ship engine must be attenuate for the employee and passenger. In yacht and cruise yacht, the noise levels in cabines are the most important criterions to the value of commodities. In this study, the noise absorbtion barrier which have resonators is experimentally studied by the 1/3 octave band noise elimination rates(%).

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Modified Weighted Filter Algorithm for Noise Elimination In Mixed Noise Environments

  • Gao, Yinyu;Kim, Nam-Ho
    • Journal of the Institute of Convergence Signal Processing
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    • v.13 no.2
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    • pp.63-69
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    • 2012
  • Noise is regarded as an unwanted component of the image because it significantly reduces image quality. And image is often corrupted by mixed noise. In this paper an efficient modified weighted filter algorithm which combines spatial weight and intensity weight is proposed for removing mixed noise. In the proposed method, the filtering mask is separated into the four sub-windows and the parameters of the weights are confirmed by calculating local standard deviation and the mean of four sub-windows' standard deviations. Considering the spatial information and intensity information, the proposed method has good performance on not only noise elimination but also preservation of details. Simulation results demonstrate that the proposed method performs better than conventional algorithms.

A Study on the development of Algorithm for Removing Noise from Road Crack Image (도로면 크랙영상의 노이즈 제거 알고리즘에 관한 연구)

  • Kim Jung-Ryeol;Lee Se-Jun;Choi Hyun-Ha;Kim Young-Suk;Lee Jun-Bok;Cho Moon-Young
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.535-538
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    • 2002
  • Machine vision algorithms, which are composed of noise elimination algorithm, crack detection and mapping algorithm, and path planning algorithm, are required for sealing crack networks effectively and automation of crack sealing.. Noise elimination algorithm is the first step so that computer take cognizance of cracks effectively. Noises should be removed because common road includes a lot of noises(mark of oil, tire, traffic lane, and sealed crack) that make it difficult the computer to acknowledge cracks accurately. The objective of this paper is to propose noise elimination algorithm, prove the efficiency of the algorithm through coding. The result of the coding is represented in this paper as well.

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Elimination of Self Noise & Doppler Effects from the Microphone Array Measurement (마이크로폰 어레이 측정에서의 도플러 효과와 자체소음 제거에 관한 실험적 연구)

  • Rhee, Wook;Park, Sung;Kim, Jai-Moo;Choi, Jong-Soo
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.16 no.7 s.112
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    • pp.677-682
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    • 2006
  • In the case of aeroacoustic test in windtunnel, measurement accuracy is reduced by not only Doppler effects but also by the microphone self noise due to airflow and high turbulence in the wall boundary layer. Microphone array measurements can be easily utilized for the solutions of these problems. In this paper, geometrical optics approach and diagonal term elimination of cross spectral matrix was introduced to the de-dopplerization and self noise reduction methods for the microphone array measurement. For the validation, beamforming tests for sinusoidal point source were performed in the closed type test section of windtunnel, and their performances of beam width and sidelobe rejection were significantly improved.

Noise Suppression in NMR Spectrum by Using Wavelet Transform Analysis

  • Kim, Daesung;Youngdo Won;Hoshik Won
    • Journal of the Korean Magnetic Resonance Society
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    • v.4 no.2
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    • pp.103-115
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    • 2000
  • Wavelet transforms are introduced as a new tool to distinguish real peaks from the noise contaminated NMR data in this paper. New algorithms of two wavelet transforms including Daubechies wavelet transform as a discrete and orthogonal wavelet transform (DWT) and Morlet wavelet transform as a continuous and nonorthogonal wavelet transform(CWT) were developed fer noise elimination. DWT and CWT method were successfully applied to the noise reduction in spectrum. The inevitable distortion of NMR spectral baseline and the imperfection in noise elimination were observed in DWT method while CWT method gives a better baseline ahape and a well noise suppressed spectrum.

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Elimination of Self Noise & Doppler Effects from the Microphone Array Measurement (마이크로폰 어레이 측정에서의 도플러 효과와 자체소음 제거에 관한 실험적 연구)

  • Rhee, Wook;Park, Sung;Choi, Jong-Soo;Kim, Jai-Moo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.822-825
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    • 2005
  • In the case of aeroacoustic test in windtunnel, measurement accuracy is reduced by not only Doppler effects but also by the microphone self noise due to airflow and high turbulence in the wall boundary layer. Microphone array measurements can be easily utilized for the solutions of these problems. In this paper, geometrical optics approach and diagonal term elimination of cross spectral matrix was introduced to the de-dopplerization and self noise reduction methods for the microphone array measurement. For the validation, beamforming tests for sinusoidal point source were performed in the closed type test section of windtunnel, and their performances of beam width and sidelobe rejection were significantly improved.

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An Implementation Of Digital Signal Processing System For The Baseline Elimination (베이스라인 제거를 위한 디지털 신호처리 시스템 구현)

  • 윤승구;박형재;박종억;배의환;김영길
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.7
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    • pp.1287-1294
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    • 2001
  • As size of waveform is very small, ECG(electrocardiogram) signal is difficult to analyze for noise which is occurred when it measures. In order to obtain ECG clearly, it must eliminate that power line interference, baseline wandering, noise of muscle constriction. In ECG, the worst problem which is recorded signal of ECG is the baseline wandering elimination, which is occurred by rhythm of respiration and muscle constriction of part from attaching to an electrode. Such the baseline is roughly irregular wandering and shaking up and down therefore the part of the baseline wandering elimination is very important because it is difficulty of ECG diagnosis. In this study, as implementation of real-time signal processing digital filter it is applicable to analyze patient's heart disease by way of design of the baseline wandering elimination system.

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