• Title/Summary/Keyword: Fast Wavelet Transform

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A Study on Frequency Estimation using Recursive Discrete Wavelet Transform (Fast Recursive Discrete Wavelet Transform 에 의한 주파수 추정)

  • Park, Chul-Won;Ban, Yu-Hyeon
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.172-173
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    • 2011
  • 전력시스템 주파수는 주파수 계전기용도 이외에 전력시스템에 대용량 집중전원 및 소규모 분산전원이 연계될 때 동기 검정 계전기와 발전기 및 소내 변압기의 과여자 상태를 감지하는 V/F 계전기에서도 사용된다. 주파수 계측장치는 주파수 및 주파수 편이를 실시간으로 정확하고 신속하게 측정함으로서 정규 주파수를 유지시키고 더 나아가 사고파급방지에 대한 책무를 수행해야 한다. DFT필터는 광범위하게 사용되었으나 주파수가 편이하게 되면 오차가 발생된다. 근래 웨이브릿 변환이 새로운 주목을 받고 것은 지속적인 연구 결과, 단일 반복 방정식 형태로 연산 부담이 적어 실시간 신호 처리에 적당한 고속 반복 이산 웨이브릿 변환이 제시되었기 때문으로 생각된다. 본 논문에서는 FRDWT에 의한 주파수 추정 기법을 제시하고자 한다. 제시된 기법의 성능 평가는 발전기 내부사고와 외부사고 데이터에 의해 이루어졌다.

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Implementation of Fingerprint Recognition System Based on the Embedded LINUX

  • Bae, Eun-Dae;Kim, Jeong-Ha;Nam, Boo-Hee
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1550-1552
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    • 2005
  • In this paper, we have designed a Fingerprint Recognition System based on the Embedded LINUX. The fingerprint is captured using the AS-S2 semiconductor sensor. To extract a feature vector we transform the image of the fingerprint into a column vector. The image is row-wise filtered with the low-pass filter of the Haar wavelet. The feature vectors of the different fingerprints are compared by computing with the probabilistic neural network the distance between the target feature vector and the stored feature vectors in advance. The system implemented consists of a server PC based on the LINUX and a client based on the Embedded LINUX. The client is a Tynux box-x board using a PXA-255 CPU. The algorithm is simple and fast in computing and comparing the fingerprints.

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Progressive Wavelet Transform Coding for Image Communication (영상통신을 위한 점진적 웨이브렛 변환 부호화)

  • 김정일;유재휘
    • Journal of the Korea Society of Computer and Information
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    • v.3 no.3
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    • pp.89-98
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    • 1998
  • In this paper, we propose new image coding using wavelet transform. The new method constructs hierarchical bit plane and progressively transports each bit plane. The proposed algorithm not only supports multi-resolution, dividing original image into special band and various resolution but also reduces blocking effects that come into JPEG In encoding time, this algorithm considers each band characters and priority of transport order, and applies to fast search of image.

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Fault Location in Combined Transmission Systems Using Wavelet Transform (웨이브렛 변환을 이용한 혼합송전계통에서의 Fault Location)

  • Jung, Chae-Kyun;Hong, Dong-Suk;Lee, Jong-Beom
    • Proceedings of the KIEE Conference
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    • 2001.05a
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    • pp.226-229
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    • 2001
  • The combined transmission lines with the underground power cables are continuously expanded in power systems. So the fault of combined transmission line is increased every year as the complication of underground transmission line. In this paper. traveling wave theory and DWT wavelet transform are used for fast and accurate detection of fault location at the combined transmission line. Traveling wave travels to each bus like surge and repeats reflection and transmission till transient signal is completely disappeared. When fault is occurred on overhead and underground tine, the fault location detecting algorithm was performed with using continuous peak value time-delay of traveling wave reflected from A bus.

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Implementation of Fingerprint Cognition System Based on the Embedded LINUX (임베디드 리눅스 기반의 지문 인식 시스템 구현)

  • Bae, Eun-Dae;Kim, Jeoung-Ha;Nam, Boo-Hee
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.204-206
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    • 2005
  • In this paper, we have designed a Fingerprint Recognition System based on the Embedded LINUX. The fingerprint is captured using the AS-S2 semiconductor sensor. To extract a feature vector we transform the image of t10he fingerprint into a column vector. The image is row-wise filtered with the low-pass filter of the Haar wavelet. The feature vectors of the different fingerprints are compared by computing with the probabilistic neural network the distance between the target feature vector and the stored feature vectors in advance. The system implemented consists of a server PC based on the LINUX and a client based on the Embedded LINUX. The client is a Tynux box-x board using a PXA-255 CPU. The algorithm is simple and fast in computing and comparing the fingerprints.

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A Novel Image Dehazing Algorithm Based on Dual-tree Complex Wavelet Transform

  • Huang, Changxin;Li, Wei;Han, Songchen;Liang, Binbin;Cheng, Peng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.10
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    • pp.5039-5055
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    • 2018
  • The quality of natural outdoor images captured by visible camera sensors is usually degraded by the haze present in the atmosphere. In this paper, a fast image dehazing method based on visible image and near-infrared fusion is proposed. In the proposed method, a visible and a near-infrared (NIR) image of the same scene is fused based on the dual-tree complex wavelet transform (DT-CWT) to generate a dehazed color image. The color of the fusion image is regulated through haze concentration estimated by dark channel prior (DCP). The experiment results demonstrate that the proposed method outperforms the conventional dehazing methods and effectively solves the color distortion problem in the dehazing process.

Recognition of Power Quality Problems using Neural Network (신경망을 이용한 전력품질 문제 인식)

  • Kim Hong-Kyun;Lee Jin-Mok;Choi Jae-Ho
    • Proceedings of the KIPE Conference
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    • 2006.06a
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    • pp.453-455
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    • 2006
  • This paper presents about recognition power quality problems using neural network. Neural network is a very powerful way to detect and classify power quality problems. But the transient like as very fast problems is difficult event to recognize. Wavelet transform is appropriate method for detecting signal irregularities. So we make features from wavelet transform. Finally we get high efficiency for detecting and classifying almost all power quality problems.

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INTRODUTION TO AN EFFICIENT IMPLEMENTATION OF THE SUBSTITUTE WAVELET INTENSITY METHOD FOR PANSHARPENING

  • Choi, Myung-Jin;Song, Jeong-Heon;Seo, Du-Chun;Lee, Dong-Han;Lim, Hyo-Suk
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.620-624
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    • 2007
  • Recently, Gonzalez-Audicana et al. proposed the substitute wavelet intensity (SWI) method which provided a solution based on the intensity-hue-saturation (IHS) method for the fusing of panchromatic (PAN) and multispectral (MS) images. Although the spectral quality of the fused MS images is enhanced, this method is not efficient enough to quickly merge massive volumes of data from satellite. To overcome this problem, we introduce a new SWI method based on a fast IHS transform to implement efficiently as an alternative procedure. In addition, we show that the method is well applicable for fusing IKONOS PAN with MS images.

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A Gray Image to Pseudocoloring Conversion and Enhancement Using FWT and CIT (FWT-CIT를 적용한 그레이 영상의 의사컬러 변환 및 향상)

  • Ryu Kwang-ryol
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.7
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    • pp.1464-1468
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    • 2004
  • The color conversion and color enhancement on gray image is presented in this paper. The pseudocoloring for RCB color components extraction from gray image is used the 2D U(Fast Wavelet Transform) for fille. bank and re-array. The each post processing is used the median filtering for noise reduction and the discrete color histogram equalization for CIT(Color Intensity Transformation). The experiment result has enhanced pseudocoloring image as PSNR 30dB over compared the processing of normal wavelet transform.

Progressive Image Coding using Wavelet Transform (웨이브렛 변환을 이용한 점진적 영상 부호화)

  • Kim, Jeong-Il;An, Kwang-Tae;Kim, Jae-Cheol;Yoo, Choong-Yeol;Lee, Kwang-Bae;Kim, Hyen-Ug
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.10
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    • pp.2640-2650
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    • 1997
  • In this paper we propose new image coding using wavelet transform. The new method constructs hierarchical bit plane and progressively transports each bit plane. The proposed algorithms not only supports multi-resolution, dividing original image into special band and various resolution but also reduces blocking effects that come int JPEG. In encoding time this algorithm considers each band characters and priority of transport order, and applies to fast search of image.

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