• Title/Summary/Keyword: transform

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Image restoration based on wavelet filter bank (웨이블렛 필터 뱅크를 이용한 영상복원)

  • 김주헌;이종수
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.1387-1390
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    • 1997
  • In this paper we propose a novel way to restore degraded image using wavelet transform & filterbank. First, we devide a degraded image into 4-suband images using UDWT(Undecimated Wavelet Transform), and then use a proper CLS (Constrained Least Square) filter in each subband. Using a proper CLS filter ineach subband, we can save high grequency components of original image. We reconstruct a restored image from the downsampled subband images using wavelet tansform. Even though there is a trade-off between ISNR and calculation loads, we reduce the calculation loads by using wavelet transform in reconstruction with a negligible degradatiion in ISNR.

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A study on application of DCT algorithm with MVP(Multimedia Video Processor) (MVP(Multimedia Video Processor)를 이용한 DCT알고리즘 구현에 관한 연구)

  • 김상기;정진현
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.1383-1386
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    • 1997
  • Discrete cosine transform(DCT) is the most popular block transform coding in lossy mode. DCT is close to statistically optimal transform-the Karhunen Loeve transform. In this paper, a module for DCT encoder is made with TMS320C80 based on JPEG and MPEG, which are intermational standards for image compression. the DCT encoder consists of three parts-a transformer, a vector quantizer and an entropy encoder.

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Measurement of Frequency Response of Giant Magnetostrictive Material by Use of M-transform

  • Harada, Hiroshi;Kashiwagi, Hiroshi;Kndo, Koshi;Yamaguchi, Teruo
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.497-501
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    • 2003
  • In this paper, impulse response of giant magnetostrictive material (GMM) is identified by using M-transform. First, the displacement of GMM was measured by using the dual frequency laser interferometer. The noise included in the measured signal was removed by using M-transform. The impulse response of the GMM was identified from the input current of the driving coil and the displacement.

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Analysis of Heart Sound Using the Wavelet Transform (Wavelet Transform을 이용한 Heart Sound Analysis)

  • 위지영;김중규
    • Proceedings of the IEEK Conference
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    • 2000.09a
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    • pp.959-962
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    • 2000
  • A heart sound algorithm, which separates the heart sound signal into four parts; the first heart sound, the systolic period, the second heart sound, and the diastolic period has been developed. The algorithm uses discrete intensity envelopes of approximations of the wavelet transform analysis method to the phonocard-iogram(PCG)signal. Heart sound a highly nonstation-ary signal, so in the analysis of heart sound, it is important to study the frequency and time information. Further more, Wavelet Transform provides more features and characteristics of the PCG signal that will help physician to obtain qualitative and quantitative measurements of the heart sound.

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An Application of the Undecimated Discrete Wavelet Transform (Undecimated 웨이블릿 변환응용)

  • Lee, Chang-Soo;Yoo, Kyung-Yul
    • Proceedings of the IEEK Conference
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    • 2000.09a
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    • pp.605-608
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    • 2000
  • This paper introduces a new structure for the undecimated discrete wavelet transform (UDWT). This structure combines the stationary wavelet transform with a lifting scheme and its design is based on a polyphase structure .where the downsampling and split stage are removed. The suggested structure inherits the simplicity of the lifting scheme, such that the inverse transform is easily implemented. The performanace of the proposed undecimated lifting is verified on a signal denoising application.

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A new hit-and-miss ratio transform and its application to warning sign segmentation (새로운 hit-and-miss 비변환과 주의 표시분할에의 응용)

  • 오주환;최태영
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.3
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    • pp.120-125
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    • 1996
  • A new hit-and-miss ratio transform is introduced as a modified hit-and-miss transform to be robust to noise, which uses a quasi-matching technique based on the fitting ratio functions. And a new gray-level object segmentation algorithm is proposed, which is based on the hit-and-miss ratio transform and threshold decomposition. The proposed segmentation images, and is similarly applicable to segmentation of an object with specific shapes form natural real images.

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Analysis of the Complementary Clipping Transform technique for the PAPR reduction of OFDM system (OFDM PAPR reduction을 위한 Complementary Clipping Transform 성능 분석)

  • Won, Seong-Ho
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2005.11a
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    • pp.57-62
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    • 2005
  • In spite of many advantages of OFDM, a major drawback for implementation is a non-linear distortion in the HPA due to a high PAPR problem. In this paper, the Complementary Clipping Transform technique (CCT) for the PAPR reduction of OFDM system is analyzed for the QPSK and QAM mapping data. BER performance and PSD in front of HPA and after HPA are analytically demonstrated.

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HEAT EQUATION IN WHITE NOISE ANALYSIS

  • KimLee, Jung-Soon
    • Journal of the Korean Mathematical Society
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    • v.33 no.3
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    • pp.541-555
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    • 1996
  • The Fourier transform plays a central role in the theory of distribution on Euclidean spaces. Although Lebesgue measure does not exist in infinite dimensional spaces, the Fourier transform can be introduced in the space $(S)^*$ of generalized white noise functionals. This has been done in the series of paper by H.-H. Kuo [1, 2, 3], [4] and [5]. The Fourier transform $F$ has many properties similar to the finite dimensional case; e.g., the Fourier transform carries coordinate differentiation into multiplication and vice versa. It plays an essential role in the theory of differential equations in infinite dimensional spaces.

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Study on the Dynamic Analysis of the Continuous System by Digital Modeling (이산화 기법에 의한 연속계의 동적 응답해석에 관한 연구)

  • 이용관;김인수;홍성욱;췌처린
    • Journal of KSNVE
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    • v.7 no.1
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    • pp.135-142
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    • 1997
  • This paper presents a digital modeling technique of the distributed system. The basic idea of the proposed technique is to discretize a continuous system with respect to the spatial coordinates using bilinear method. The response of the discretized system is analyzed by Laplace transform and z-transform. The computational results in torsional shaft and Timoshenko beam using the proposed technique are compared with the exact solutions and the results of finite element method.

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SPECTRAL THEOREMS ASSOCIATED TO THE DUNKL OPERATORS

  • Mejjaoli, Hatem
    • Korean Journal of Mathematics
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    • v.24 no.4
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    • pp.693-722
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    • 2016
  • In this paper, we characterize the support for the Dunkl transform on the generalized Lebesgue spaces via the Dunkl resolvent function. The behavior of the sequence of $L^p_k$-norms of iterated Dunkl potentials is studied depending on the support of their Dunkl transform. We systematically develop real Paley-Wiener theory for the Dunkl transform on ${\mathbb{R}}^d$ for distributions, in an elementary treatment based on the inversion theorem. Next, we improve the Roe's theorem associated to the Dunkl operators.