• Title/Summary/Keyword: N-transform

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Image Coding Using Bit-Planes of Wavelet Coefficients (웨이블렛 변환 계수의 비트 플레인을 이용한 영상부호화)

  • 김영로;홍원기;고성제
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.4
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    • pp.714-725
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    • 1997
  • This paper proposes an image compression method using the wavelet transform and bit-plane coding of wavelet coefficients. The hierarchical application of wavelet transform to an image produces one low resoluation(the subband with lowest frequency) image and several high frequency subbands. In the proposed method, the low resolution image is compressed by a lossless method at 8 bits per each coefficient. However, the high frequency subbands are decomposed into 8 bit planes. With an adptive block coding method, the decomposed bit planes are effectively compressed using localized edge information in each bit plane. In addition, the propsoed method can control bit rates by selectively eliminating lessimportant subbands of low significant bit planes. Experimental results show that the proposed scheme has better performance in the peak signal to noise ratio (PSNR) and compression rate than conventional image coding methods using the wavelet transform and vector quantization.

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Angle Invariant and Noise Robust Barcode Detection System (기울기와 노이즈에 강인한 바코드 검출 시스템)

  • Park, Dongjin;Jun, Kyungkoo
    • Journal of KIISE
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    • v.42 no.7
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    • pp.868-877
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    • 2015
  • The barcode area extraction from images has been extensively studied, and existing methods exploit frequency characteristics or depend on the Hough transform (HT). However, the slantedness of the images and noise affects the performance of these approaches. Moreover, it is difficult to deal with the case where an image contains multiple barcodes. We therefore propose a barcode detection algorithm that is robust under such unfavorable conditions. The pre-processing step implements a probabilistic Hough transform to determine the areas that contain barcodes with a high probability, regardless of the slantedness, noise, and the number of instances. Then, a frequency component analysis extracts the barcodes. We successfully implemented the proposed system and performed a series of barcode extraction tests.

RADIAL SYMMETRY AND SPHERICAL NODAL SET OF SOLUTIONS OF NONLINEAR ELLIPTIC EQUATIONS

  • Seok, Yong-Jing
    • Communications of the Korean Mathematical Society
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    • v.10 no.1
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    • pp.133-135
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    • 1995
  • In this note, we will investigate the radial symmetry of some kind of solutions of nonlinear ellipitic equations $$ \Delta U = f(U) $$ $$ (1.1) U = 0 in B $$ $$ U \in C^2 (\bar{B}) on \partial B$$ Here f is $C^1$ and B denotes a n-dimensional unit ball in $R^n$.

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A Coherent Algorithm for Noise Revocation of Multispectral Images by Fast HD-NLM and its Method Noise Abatement

  • Hegde, Vijayalaxmi;Jagadale, Basavaraj N.;Naragund, Mukund N.
    • International Journal of Computer Science & Network Security
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    • v.21 no.12spc
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    • pp.556-564
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    • 2021
  • Numerous spatial and transform-domain-based conventional denoising algorithms struggle to keep critical and minute structural features of the image, especially at high noise levels. Although neural network approaches are effective, they are not always reliable since they demand a large quantity of training data, are computationally complicated, and take a long time to construct the model. A new framework of enhanced hybrid filtering is developed for denoising color images tainted by additive white Gaussian Noise with the goal of reducing algorithmic complexity and improving performance. In the first stage of the proposed approach, the noisy image is refined using a high-dimensional non-local means filter based on Principal Component Analysis, followed by the extraction of the method noise. The wavelet transform and SURE Shrink techniques are used to further culture this method noise. The final denoised image is created by combining the results of these two steps. Experiments were carried out on a set of standard color images corrupted by Gaussian noise with multiple standard deviations. Comparative analysis of empirical outcome indicates that the proposed method outperforms leading-edge denoising strategies in terms of consistency and performance while maintaining the visual quality. This algorithm ensures homogeneous noise reduction, which is almost independent of noise variations. The power of both the spatial and transform domains is harnessed in this multi realm consolidation technique. Rather than processing individual colors, it works directly on the multispectral image. Uses minimal resources and produces superior quality output in the optimal execution time.

A METHOD FOR SOLVING A FUZZY LINEAR PROGRAMMING

  • Peraei, E.Yazdany;Maleki, H.R.;Mashinchi, M.
    • Journal of applied mathematics & informatics
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    • v.8 no.2
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    • pp.439-448
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    • 2001
  • In this paper a fuzzy linear programming problem is presented. Then using the concept of comparison of fuzzy numbers, by the aid of the Mellin transform, we introduce a method for solving this problem.

AN ELECTROMAGNETIC FREE CONVECTION FLOW OF A MICROPOLAR FLUID WITH RELAXATION TIME

  • Zakaria, M.
    • Journal of applied mathematics & informatics
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    • v.8 no.2
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    • pp.539-550
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    • 2001
  • In the present investigation, we study the influence of a transverse magnetic field through a porous medium. Laplace transform techniques are used to derive the solution in the Laplace transform domain. The inversion process is carried out using a numerical method based on Fourier series expansions. Numerical computations for the temperature, the microrotation and the velocity distributions as well as for the induced magnetic and electric fields and carried out and represented graphically.

Fast Simulation for Excessive Backlogs in Tandem Networks

  • Lee, Jiyeon
    • Communications for Statistical Applications and Methods
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    • v.7 no.2
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    • pp.499-511
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    • 2000
  • We consider a stable tandem network which consists of two M/M/1 nodes and study the probability that the total backlog exceeds a large level N. Since the excessive backlog is a rare event, it is difficult to estimate this probability efficiently by using the crude Monte Carlo simulation. Instead we perform the ;$h$-transform proposed by McDonald(1999) to obtain the twisted network, in which the node with the larger load is overloaded. Then we use it to run the fast simulation.

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AN APPROXIMATION OF THE HANKEL TRANSFORM FOR ABSOLUTELY CONTINUOUS MAPPINGS

  • DRAGOMIR, N.M.;DRAGOMIR, S.S.;GU, M.;GAN, X.;WHITE, R.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.6 no.1
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    • pp.17-31
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    • 2002
  • Using some techniques developed by Dragomir and Wang in the recent paper [2] in connection to Ostrowski integral inequality, we point out some approximation results for the Henkel's transform of absolutely continuous mapping.

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THE LIMITING SPECTRAL DISTRIBUTION FUNCTION OF LARGE DIMENSIONAL RANDOM MATERICES OF SAMPLE COVARIANCE TYPE

  • Choi, Sang-Il
    • Journal of applied mathematics & informatics
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    • v.5 no.2
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    • pp.465-474
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    • 1998
  • Results on the analytic behavior to the limiting spectral distribution of matrices of sample convariance type. studied in Marcenko and Pastur [2] are derived. using the Stieltjes transform it is shown that the limiting distrbution has a continuous derivative away from zero the derivative being analytic whenever it is positive and the behavior of it resembles the behavior of a square root function near the boundary of its support.

TIME FRACTIONAL ADVECTION-DISPERSION EQUATION

  • Liu, F.;Anh, V.V.;Turner, I.;Zhuang, P.
    • Journal of applied mathematics & informatics
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    • v.13 no.1_2
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    • pp.233-245
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    • 2003
  • A time fractional advection-dispersion equation is Obtained from the standard advection-dispersion equation by replacing the firstorder derivative in time by a fractional derivative in time of order ${\alpha}$(0 < ${\alpha}$ $\leq$ 1). Using variable transformation, Mellin and Laplace transforms, and properties of H-functions, we derive the complete solution of this time fractional advection-dispersion equation.