• Title/Summary/Keyword: Projection algorithm

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EIT imaging with the projection filter

  • Kim, Bong-Seok;Kim, Min-Chan;Kim, Sin;Kim, Kyung-Youn
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.396-401
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    • 2003
  • Electrical impedance tomography(EIT) is a relatively new imaging modality in which the internal impedivity distribution is reconstructed based on the known sets of injected currents and measured voltages on the surface of the object. In this paper, an effective dynamic EIT imaging scheme is presented based on the projection filtering to estimate the unknown resistivity distribution. In particular, pre-integration (pre-grouping) technique is employed to stabilize the inverse algorithm. We carried out computer simulations with synthetic data to illustrate the reconstruction performance of the proposed algorithm.

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Shape Measurement and Representation of 3-D Curved Objects using Simple Back-Projection algorithm (단순역투영법을 이용한 3차원 곡면물체의 형상계측 및 표현)

  • 최종수;김덕수
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.22 no.1
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    • pp.61-67
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    • 1985
  • The new computer vision system which can reconstruct contours of parallel fault planes with horizon of 3-D curved objects has been developed. With the system, the shape of 3-D objects was measured by Simple Back-Projection algorithm which is a fundamental one in C.T.(Computed Tomography). And, the curvature in differential geometry characterizes any curve. Devising it, the method to represent each contour of 3-D curved objects with the system is described in this paper.

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A Study on the Calibration of Shape Measurement System Using Digital moire (Digital moire 형상측정 시스템의 보정에 관한 연구)

  • 유원재;김도훈;안재웅;강영준;노형민
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.199-202
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    • 2002
  • Moire topography method is a well-known non-contacting 3-D measurement method. Recently, the automatic 3-D measurement by moire topography has been required since the method was frequently applied to the engineering and medical fields. 3-D measurement using digital projection moire topography is very attractive because of its high measuring speed and high sensitivity. In this paper, using different N-bucket algorithm method of digital projection moire topography is tested to measuring object with the 2$\pi$-ambiguity problem. Experimental results prove that the proposed scheme is capable of finding measurement errors that decreased more by using the flour-three step algorithm method than the same step in the phase shifting of different pitchs.

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OPTIMAL ERROR ESTIMATE FOR SEMI-DISCRETE GAUGE-UZAWA METHOD FOR THE NAVIER-STOKES EQUATIONS

  • Pyo, Jae-Hong
    • Bulletin of the Korean Mathematical Society
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    • v.46 no.4
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    • pp.627-644
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    • 2009
  • The gauge-Uzawa method which has been constructed in [11] is a projection type method to solve the evolution Navier-Stokes equations. The method overcomes many shortcomings of projection methods and displays superior numerical performance [11, 12, 15, 16]. However, we have obtained only suboptimal accuracy via the energy estimate in [11]. In this paper, we study semi-discrete gauge-Uzawa method to prove optimal accuracy via energy estimate. The main key in this proof is to construct the intermediate equation which is formed to gauge-Uzawa algorithm. We will estimate velocity errors via comparing with the intermediate equation and then evaluate pressure errors via subtracting gauge-Uzawa algorithm from Navier-Stokes equations.

Utilization of a Gauss-Seidel Fast Affine Projection Algorithm for Active Noise Control of a 2nd-order Volterra system with a noisy secondary path (GS-FAP 알고리즘 적용한 2차 볼테라 시스템의 능동 소음 제거)

  • Seo, Jae-Beom;Kim, Kyoung-Jae;Nam, Sang-Won
    • Proceedings of the KIEE Conference
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    • 2007.04a
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    • pp.395-397
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    • 2007
  • In this paper, a Gauss-Seidel fast affine projection (GS-FAP) algorithm developed for the linear active noise control (ANC) is further utilized for nonlinear ANC of a 2nd-order Volterra systems with a nonlinear primary path and a noisy secondary path. The simulation results, obtained by applying adaptive Volterra filtering, show that the proposed approach yields more stable and faster nonlinear AN.C, compared with the conventional methods for the nonlinear ANC in case of noisy plant models.

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A Moving Target Tracking Algorithm Using Integral Projection (가산 투엽법을 이용한 이동 물체 추적 방법)

  • 김태원;서일홍;양해원;오상록;임달호
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.38 no.7
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    • pp.569-581
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    • 1989
  • This paper deals with a tracking algorithm based on integral projection which tracks moving targets with varying brightness and size. An adaptive windowing technique is employed to reduce the sensitivity of the system to the complex background image and also to reduce the computational load. The threshold value is determined by considering both the size and the threshold value of the brightness intensity of the recognized target obtained in the previous processing step. Window position is estimated by using the information of the velocity and acceleration of the target. And integral projection is applied to find the position of the target in the window accurately. Experimental results show that moving targets with varying brightness and size can be tracked properly in noisy environments.

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RECONSTRUCTION OF LIMITED-ANGLE CT IMAGES BY AN ADAPTIVE RESILIENT BACK-PROPAGATION ALGORITHM

  • Kazunori Matsuo;Zensho Nakao;Chen, Yen-Wei;Fath El Alem F. Ah
    • Proceedings of the IEEK Conference
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    • 2000.07b
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    • pp.839-842
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    • 2000
  • A new and modified neural network model Is proposed for CT image reconstruction from four projection directions only. The model uses the Resilient Back-Propagation (Rprop) algorithm, which is derived from the original Back-Propagation, for adaptation of its weights. In addition to the error in projection directions of the image being reconstructed, the proposed network makes use of errors in pixels between an image which passed the median filter and the reconstructed one. Improved reconstruction was obtained, and the proposed method was found to be very effective in CT image reconstruction when the given number of projection directions is very limited.

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Strong Convergence of a Bregman Projection Method for the Solution of Pseudomonotone Equilibrium Problems in Banach Spaces

  • Olawale Kazeem Oyewole;Lateef Olakunle Jolaoso;Kazeem Olalekan Aremu
    • Kyungpook Mathematical Journal
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    • v.64 no.1
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    • pp.69-94
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    • 2024
  • In this paper, we introduce an inertial self-adaptive projection method using Bregman distance techniques for solving pseudomonotone equilibrium problems in reflexive Banach spaces. The algorithm requires only one projection onto the feasible set without any Lipschitz-like condition on the bifunction. Using this method, a strong convergence theorem is proved under some mild conditions. Furthermore, we include numerical experiments to illustrate the behaviour of the new algorithm with respect to the Bregman function and other algorithms in the literature.

AN ALGORITHM FOR SYMMETRIC INDEFINITE SYSTEMS OF LINEAR EQUATIONS

  • YI, SUCHEOL
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.3 no.2
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    • pp.29-36
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    • 1999
  • It is shown that a new Krylov subspace method for solving symmetric indefinite systems of linear equations can be obtained. We call the method as the projection method in this paper. The residual vector of the projection method is maintained at each iteration, which may be useful in some applications.

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