• Title/Summary/Keyword: interpolation function

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Modified Raised-Cosine Interpolation and Application to Image Processing (변형된 상승여현 보간법의 제안과 영상처리에의 응용)

  • 하영호;김원호;김수중
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.4
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    • pp.453-459
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    • 1988
  • A new interpolation function, named modified raised-cosine interpolation, is proposed. This function is derived from the linear combination of weighted triangular and raised-cosine functions to reduce the effect of side lobes which incur the interpolation error. Interpolation error reduces significantly for higher-order convolutional interpolation functions of linear operators, but at the expense of resolution error due to the attenuation of main lobe. However, the proposed interpolation function enables us to reduce the side lobes as well as to preserve the main lobe. To prove practicality, this function is applied in image reconstruction and enlargement.

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A Study on Fuzzy Wavelet Basis Function for Image Interpolation

  • Byun, Oh-Sung;Moon, Sung-Ryong
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.4 no.3
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    • pp.266-270
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    • 2004
  • The image interpolation is one of an image preprocessing process to heighten a resolution. The conventional image interpolation used much to concept that it put in other pixel to select the nearest value in a pixel simply, and use much the temporal object interpolation techniques to do the image interpolation by detecting motion in a moving picture presently. In this paper, it is proposed the image interpolation techniques using the fuzzy wavelet base function. This is applied to embody a correct edge image and a natural image when expand part of the still image by applying the fuzzy wavelet base function coefficient to the conventional B-spline function. And the proposal algorithm in this paper is confirmed to improve about 1.2831 than the image applying the conventional B-spline function through the computer simulation.

CONSTRUCTION OF POSITIVE INTERPOLATION FUNCTIONS FOR DIFFUSION TENSOR

  • Shim, Hong-Tae
    • Journal of applied mathematics & informatics
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    • v.23 no.1_2
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    • pp.563-570
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    • 2007
  • There has been a considerable research interest in medical communities for neuronal fiber tracking with magnetic resonance diffusion tensor imaging(DTI). DTI data have abundant structural boundaries that need to be preserved during interpolation to facilitate fiber tracking. Sigmoid function has been used in recent papers but the sigmoid function still is not good enough to be served as an positive interpolation in mathematical point of view. In this paper, we construct and provide two families positive cardinal interpolation functions.

A NON-RECURSIVE APPROACH TO NEVANLINNA-PICK INTERPOLATION PROBLEM

  • Kim, Jeongook
    • Honam Mathematical Journal
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    • v.41 no.4
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    • pp.823-835
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    • 2019
  • A solution for Nevanlinna-Pick interpolation problem with low complexity is constructed via non-recursive method. More precisely, a stable rational function satifying the given interpolation data in the complex right half plane is found by solving a homogeneous interpolation problem related to a minial interpolation problem for the given data in the right half plane together with its mirror-image data.

Sliding Mode Control with Nonlinear Interpolation in Variable Boundary Layer

  • Kim, Yookyung;Jeon, Gijoon
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.35.1-35
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    • 2002
  • $\textbullet$ Sliding mode control (SMC) with nonlinear interpolation in variable boundary layer (VBL) is proposed $\textbullet$ A sigmoid function is used for nonlinear interpolation in VBL. $\textbullet$ The Parameter of the sigmoid function is tuned by fuzzy controller $\textbullet$ The choice of parameter for the sigmoid function is guided by FC. $\textbullet$ The parameter is continuously updated as boundary layer thickness varies. $\textbullet$ The proposed method hasbetter tracking performance than the conventional linear interpolation $\textbullet$ To demonstrate its performance the proposed control algorithm is applied to a nonlinear system.

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IMPROVED STATIONARY $L_p$-APPROXIMATION ORDER OF INTERPOLATION BY CONDITIONALLY POSITIVE DEFINITE FUNCTIONS

  • Yoon, Jung-Ho
    • Journal of applied mathematics & informatics
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    • v.14 no.1_2
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    • pp.365-376
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    • 2004
  • The purpose of this study is to show that the accuracy of the interpolation method can be at least doubled when additional smoothness requirements and boundary conditions are met. In particular, as a basis function, we are interested in using a conditionally positive definite function $\Phi$ whose generalized Fourier transform is of the form $\Phi(\theta)\;=\;F(\theta)$\mid$\theta$\mid$^{-2m}$ with a bounded function F > 0.

Space-Variant B-Spline Functions for Image Interpolation (영상보간을 위한 공간변화(Space-Variant) B-Splin 함수)

  • 이병길;김순자;하영호
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.40 no.4
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    • pp.394-401
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    • 1991
  • B-spline function is generally used for an image interpolation because of its smoothness and continuity, but it accompanies a large amount of blurring effect. In this paper, a space-variant B-spline interpolation function is proposed through deblurring process followed by de-aliasing process. The proposed function has parametric expression and performs smoothing and edge-enhancement adaptively in the interpolation process according to local property of the image. Application of this function to image enlargement, rotation, and curve representation producted good results. Even in the presence of noise, noise smoothing effect as well as edge-enhancement were observed in the image interpolation process.

A Study on Wave Transformation Analysis using Higher-Order Finite Element (고차유한요소의 파랑변형해석에의 적용에 관한 소고)

  • Jung, Tae-Hwa;Lee, Jong-In;Kim, Young-Taek;Ryu, Yong-Uk
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.21 no.2
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    • pp.108-116
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    • 2009
  • The present study introduces a Legendre interpolation function which is capable of analyzing wave transformation effectively in a finite element method. A Lagrangian interpolation function has been mostly used for a finite element method with a higher-order interpolation function. Although this function has an advantage of giving an accurate result with less number of elements, simulation time increases. Calculation time can be reduced by mass lumping, whereas the accuracy of solution is lowered. In this study, we introduce a modified Lagrangian interpolation function, Legendre cardinal interpolation, which can reduce simulation time with keeping up favorable accuracy. Through various numerical simulations using a Boussinesq equations model, the superiority of the Legendre cardinal interpolation function to a Lagrangian interpolation function was shown.