• Title/Summary/Keyword: Laplacian Operator

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QUANTUM CONTROL OF PARTICLES AT MATTER SURFACE OUTSIDE THE DOMAIN

  • Quan-Fang Wang
    • Nonlinear Functional Analysis and Applications
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    • v.28 no.1
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    • pp.11-36
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    • 2023
  • In this presentation, the particles at the matter surface (metal, crystal, nano) will be considered as the control target outside the physical domain. As is well known that control problems of quantum particles at surface had been investigated in various aspects in last couple of years, but the realization of control would become rather difficult than theoretical results. Especially, whether surface control would be valid? what kind of particles at what kind of matter surfaces can be controlled? so many questions still left as the mystery in the current research literature and papers. It means that the direct control sometime does not easy. On the other hands, control outside the physical domain is quite a interest consideration in mathematics, physics and chemistry. The main plan is to take the quantum systems operator (such as Laplacian ∆) in the form of fractional operator (∆s , 0 < s < 1), then to consider the control outside of physical domain. Fortunately, there are many published articles in the field of applied mathematics can be referred for the achievement of control outside of domain. The external quantum control would be a fresh concept to do the physical control, first in the theoretic, second in the computational, final in the experimental issues.

A Statistical Analysis of Edge Enhancing Filters and Their Effects on Edge Detection (에지개선 필터들의 통계적 분석과 에지검출에 대한 영향)

  • 박순영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.11
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    • pp.1635-1644
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    • 1993
  • In this paper, we examine the statistical characteristics of edge enhancing filters and their efficacy as preprocessing operator before edge detection. In particular, edge enhancing filters called the Comparison and Selection(CS), Hachimura-kuwahara(HK), and Selective Average(SA) filters are considered. These filters can reduce noise while producing step-type edges, thus seem to be effective for preprocessing noisy images prior to applying edge detecors. The ability of edge enhancing filters to suppress white Gaussian noise and the error probabilities occured during the edge detection following SA prefiltering are evaluated statistically through numerical analysis. The effect of prefiltering on edge detection is assessed by applying the edge enhancing fitters to a noise image degraded by additive white noise prior to applying the Sobel operator and the Laplacian of Gaussian( LoG ) operator, respectively. It is shown that the edge enhancing filters tend to produce ideal step-type edges while reducing the noise reasonably well, and the use of edge enhancing filters prior to edge detection can improve the performance of subsequent edge detector.

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Wavelet-Based Noise Estimation in Image (웨이브릿에 기반한 영상의 잡음추정)

  • 안태경;우동헌;김재호
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.747-750
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    • 2001
  • The paper presents an algorithm for estimating the variance of additive zero mean Gaussian noise in an image. The algorithm uses the wavelet transform which is a good tool for energy compaction. The algorithm consists of three steps. At first, high frequency components, wavelet coefficients in HH band, are generated from a noisy image by the wavelet transform. In a second step, high frequency components which are out of the noise range ate eliminated. Finally, if the image has many components eliminated in the previous step, then its noise estimated value is reduced. Experimental results show that the wavelet filter has better performance than the other high pass filters such as a Laplacian filter, residual from a median filter, residual from a mean filter, and a difference operator. In various images, the algorithm reduces 50% of estimated error on an average.

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CLIFFORD $L^2$-COHOMOLOGY ON THE COMPLETE KAHLER MANIFOLDS II

  • Bang, Eun-Sook;Jung, Seoung-Dal;Pak, Jin-Suk
    • Bulletin of the Korean Mathematical Society
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    • v.35 no.4
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    • pp.669-681
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    • 1998
  • In this paper, we prove that on the complete Kahler manifold, if ${\rho}(x){\geq}-\frac{1}{2}{\lambda}_0$ and either ${\rho}(x_0)>-\frac{1}{2}{lambda}_0$ at some point $x_0$ or Vol(M)=${\infty}$, then the Clifford $L^2$ cohomology group $L^2{\mathcal H}^{\ast}(M,S)$ is trivial, where $\rho(x)$ is the least eigenvalue of ${\mathcal R}_x + \bar{{\mathcal R}}(x)\;and\;{\lambda}_0$ is the infimum of the spectrum of the Laplacian acting on $L^2$-functions on M.

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TRANSLATION SURFACES IN THE 3-DIMENSIONAL GALILEAN SPACE SATISFYING ∆IIxiixi

  • Cakmak, Ali;Karacan, Murat Kemal;Kiziltug, Sezai;Yoon, Dae Won
    • Bulletin of the Korean Mathematical Society
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    • v.54 no.4
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    • pp.1241-1254
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    • 2017
  • In this paper, we classify translation surfaces in the three dimensional Galilean space ${\mathbb{G}}_3$ satisfying some algebraic equations in terms of the coordinate functions and the Laplacian operators with respect to the second fundamental form of the surface. We also give explicit forms of these surfaces.

Raised characters rocognition of rubber tires using neural network (Neural Network를 이용한 고무 타이어의 돌출 문자 인식)

  • 김경민;박중조;김민기;박귀태
    • 제어로봇시스템학회:학술대회논문집
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    • 1993.10a
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    • pp.864-869
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    • 1993
  • This paper presents the problem of automatically recognizing embossed or molded characters which are raised from the side wall on rubber tire. In the tire image objects have approximately the same gray-value as the background and because of the tire geometry, illumination of the surface is nonhomogenous. Therefore it is difficult to recognize the raised tire character. In this paper, for describing the process of processing three steps have been proposed: 1) MIN & MAX smoothing operation filter, 2) edge detection algorithm using modified laplacian operator, 3) noise rejection. Afterwards, segmentation is done to attain characters from tire image by projection method. The recognition of the characters in the segmented image is carried out by using multilayered neural network, which is insensitive to the noise.

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3D Shape Recovery using Line Fitting (Line Fitting 을 이용한 삼차원 형상복원)

  • Shim, Seong-O;Malik, Aamir Saeed;Choi, Tae-Sun
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.905-906
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    • 2008
  • This paper presents a method where the best focues points are calculated using line fitting. Two datasets are selected for each pixel based on the maximum value which is calculated using Laplacian operator. Then linear regression model is used to find lines that approximate these datasets. The best fit lines are found using least squares method. After approximating the two lines, their intersection point is calculated and weights are assigned to calculate the new value for the depth map.

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Development of Pipe-Inspection System Using Computer Vision

  • Park, Chan-ho;Lee, Byungryoung;Soonyoung Yang;Kyungkwan Ahn;Hyunog Oh
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.99.1-99
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    • 2002
  • In this paper, a computer-vision based pipe-inspection algorithm is developed. The algorithm uses the modified Hough transformation and a line-scanning approach to identify the edge line and radius of the pipe image, from which the eccentricity and dimension of the pipe-end is calculated. Line and circle detection was performed using Laplacian operator with input image which are acquired from the front and side cameras. In order to minimize the memory usage and the processing time, a clustering method with the modified Hough transformation for line detection. The dimension of inner and outer radius of pipe is calculated by proposed line-scanning method. The method scans several lines along t...

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Face Tracking Using Skin-Color and Robust Hausdorff Distance in Video Sequences

  • Park, Jungho;Park, Changwoo;Park, Minyong
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.540-543
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    • 1999
  • We propose a face tracking algorithm using skin-color based segmentation and a robust Hausdorff distance. First, we present L*a*b* color model and face segmentation algorithm. A face is segmented from the first frame of input video sequences using skin-color map. Then, we obtain an initial face model with Laplacian operator. For tracking, a robust Hausdorff distance is computed and the best possible displacement t. is selected. Finally, the previous face model is updated using the displacement t. It is robust to some noises and outliers. We provide an example to illustrate the proposed tracking algorithm in video sequences obtained from CCD camera.

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ROBUST CONTROLLER DESIGN FOR THE NUCLEAR REACTOR POWER BY EXTENDED FREQUENCY RESPONSE METHOD

  • Lee, Yoon-Joon;Na, Man-Gyun
    • Nuclear Engineering and Technology
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    • v.38 no.6
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    • pp.551-560
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    • 2006
  • In this study, a controller for a nuclear reactor power is designed. The reactor is modeled using the three dimensional reactor design code MASTER. From the relationship of the input and output of the reactor code, a reactor dynamic model is derived by the system identification method. This model is more realistic than the one based on mathematical theories. With this model, a robust controller is designed by the extended frequency response method. As this method has the same theoretical background as the classical method, all of the existing design techniques of the classical method can be used directly. Furthermore, by introducing the real part of a Laplacian operator into the frequency response, the control design specification can be considered at the initial stage of design. The designed controller is simple, and gives a sufficient robustness with good performance.