• 제목/요약/키워드: Laplacian operator

검색결과 123건 처리시간 0.019초

영상복원에서의 정칙화 연산자 분석 (Analysis on the Regularization Parameter in Image Restoration)

  • 전우상;이태홍
    • 한국멀티미디어학회논문지
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    • 제2권3호
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    • pp.320-328
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    • 1999
  • 정칙화 반복복원 과정에 사용되는 정칙화 연산자는 Laplacian 연산자를 주로 사용하고 있으나, 일반적으로 미분 연산자를사용하게 되어있다. 본 논문에서는 정칙화 연산자로서의 일반적인 미분연산자틀과 본 연구실에서 사용 되어 온 I-H 연산자의 성능을 비교, 검토하여 분석하였다. 선형적인 움직임에 의한 훼손된 영상에서는, 평면부분은 I-H 연산자가 Laplacian 연산자보다 복원효과와 MSE의 수렴성이 안정된 것을 알 수 있었으며 윤곽부분은 Laplacian 연산자가 I-H 연산자보다 MSE의 수렴성 및 복원효과가 뛰어남을 알 수 있었다. 가우시안에 의해 훼손된 영상에서는, 융곽부분은 I-H 연산자가 Laplacian 연산자보다 MSE의 수렴성 및 복원효과가뛰어나며 평변부분에서는Laplacian 연산자가 I-H 연산자보다 MSE 변에서 안정적으로 F수렴함을 알 수 있었다. 정칙화 이론은 잡음의 평활화와 윤곽의 복원을 동시에 고려하여 처리하기 때문에 영역을 평면부분과 중간 부분 그리고 윤곽부분으로 나누어서 처리결과에 대한 MSE를 비교하였다. Laplacian 연산자와 I-H 연산자는 정칙화 연산자로 사용하기에 적합하였고 다른 미분 연산자들은 반복횟수에 따라 발산하는 것으로 나타났다.

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수리형태학적 Laplacian 연산을 이용한 새로운 동영상 Detail 추출 방법 (A NEW DETAIL EXTRACTION TECHNIQUE FOR VIDEO SEQUENCE CODING USING MORPHOLOGICAL LAPLACIAN OPERATOR)

  • 어진우;김희준
    • 전기전자학회논문지
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    • 제4권2호
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    • pp.288-294
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    • 2000
  • 본 논문에서는 동영상 압축 기법을 향상시키기 위하여 효율적인 detail 추출 기법을 제안한다. 기존의 top-hat 변환을 이용한 기법은 고립되어 있고 시각적으로 중요한 detail의 추출에는 효율적이지만, 영역의 경계에서는 비효율적이다. 제안된 기법은 수리형태학적 Laplacian 연산의 영역경계 정보추출의 성질을 이용하여 압축을 향상시키고 저비트율을 제공한다. 실험결과를 통해서 제안된 기법이 기존 기법보다 효율적임을 보이고 수리형태학적 Laplacian 연산 적용의 타당성을 설명한다.

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SOME RESULTS OF EVOLUTION OF THE FIRST EIGENVALUE OF WEIGHTED p-LAPLACIAN ALONG THE EXTENDED RICCI FLOW

  • Azami, Shahroud
    • 대한수학회논문집
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    • 제35권3호
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    • pp.953-966
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    • 2020
  • In this article we study the evolution and monotonicity of the first non-zero eigenvalue of weighted p-Laplacian operator which it acting on the space of functions on closed oriented Riemannian n-manifolds along the extended Ricci flow and normalized extended Ricci flow. We show that the first eigenvalue of weighted p-Laplacian operator diverges as t approaches to maximal existence time. Also, we obtain evolution formulas of the first eigenvalue of weighted p-Laplacian operator along the normalized extended Ricci flow and using it we find some monotone quantities along the normalized extended Ricci flow under the certain geometric conditions.

FRACTIONAL HYBRID DIFFERENTIAL EQUATIONS WITH P-LAPLACIAN OPERATOR

  • CHOUKRI DERBAZI;ABDELKRIM SALIM;HADDA HAMMOUCHE;MOUFFAK BENCHOHRA
    • Journal of Applied and Pure Mathematics
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    • 제6권1_2호
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    • pp.21-36
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    • 2024
  • In this paper, we study the existence of solutions for hybrid fractional differential equations with p-Laplacian operator involving fractional Caputo derivative of arbitrary order. This work can be seen as an extension of earlier research conducted on hybrid differential equations. Notably, the extension encompasses both the fractional aspect and the inclusion of the p-Laplacian operator. We build our analysis on a hybrid fixed point theorem originally established by Dhage. In addition, an example is provided to demonstrate the effectiveness of the main results.

ANTI-PERIODIC SOLUTIONS FOR HIGHER-ORDER LIÉENARD TYPE DIFFERENTIAL EQUATION WITH p-LAPLACIAN OPERATOR

  • Chen, Taiyong;Liu, Wenbin
    • 대한수학회보
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    • 제49권3호
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    • pp.455-463
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    • 2012
  • In this paper, by using degree theory, we consider a kind of higher-order Li$\acute{e}$enard type $p$-Laplacian differential equation as follows $$({\phi}_p(x^{(m)}))^{(m)}+f(x)x^{\prime}+g(t,x)=e(t)$$. Some new results on the existence of anti-periodic solutions for above equation are obtained.

Operator-splitting methods respecting eigenvalue problems for shallow shelf equations with basal drag

  • Geiser, Jurgen;Calov, Reinhard
    • Coupled systems mechanics
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    • 제1권4호
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    • pp.325-343
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    • 2012
  • We present different numerical methods for solving the shallow shelf equations with basal drag (SSAB). An alternative approach of splitting the SSAB equation into a Laplacian and diagonal shift operator is discussed with respect to the underlying eigenvalue problem. First, we solve the equations using standard methods. Then, the coupled equations are decomposed into operators for membranes stresses, basal shear stress and driving stress. Applying reasonable parameter values, we demonstrate that the operator of the membrane stresses is much stiffer than the operator of the basal shear stress. Here, we could apply a new splitting method, which alternates between the iteration on the membrane-stress operator and the basal-shear operator, with a more frequent iteration on the operator of the membrane stresses. We show that this splitting accelerates and stabilize the computational performance of the numerical method, although an appropriate choice of the standard method used to solve for all operators in one step speeds up the scheme as well.

$L^{\infty}$-CONVERGENCE OF MIXED FINITE ELEMENT METHOD FOR LAPLACIAN OPERATOR

  • Chen, Huan-Zhen;Jiang, Zi-Wen
    • Journal of applied mathematics & informatics
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    • 제7권1호
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    • pp.61-82
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    • 2000
  • In this paper two so-called regularized Green's functions are introduced to derive the optimal maximum norm error estimates for the unknown function and the adjoint vector-valued function for mixed finite element methods of Laplacian operator. One contribution of the paper is a demonstration of how the boundedness of $L^1$-norm estimate for the second Green's function ${\lambda}_2$ and the optimal maximum norm error estimate for the adjoint vector-valued function are proved. These results are seemed to be to be new in the literature of the mixed finite element methods.

이미지프로세싱을 이용한 가공면의 표면거칠기 측정에 관한 연구 (A study on the cutting surface roughness measurement by image processing)

  • 소의열;임영호
    • 한국정밀공학회지
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    • 제11권5호
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    • pp.124-133
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    • 1994
  • Many of non-contact measuring systems are used to estimate surface characteristics owing to their advantages of high speed and undanaged test. In this paper, a new measuring system is proposed to acquire image from CCD camera through back light illumination. Lowpass filter is very useful in view of noise removal and optimum binary image can be made through histogram equalization which is one of the histogram technique to maximize brightness intensity between workpiece and background. Laplacian operator is used to detect workpiece edge from binary image. In case of image treatment applying Laplacian operator, surface roughness is calculated by introducing conversion coefficient for coordinate of pixel which edge is composed of. In summary, the work is concerned with the development of a new technique for roughness measurement by the image processing in turning.

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