• Title/Summary/Keyword: invariant convergence

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Camera Motion Parameter Estimation Technique using 2D Homography and LM Method based on Invariant Features

  • Cha, Jeong-Hee
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.5 no.4
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    • pp.297-301
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    • 2005
  • In this paper, we propose a method to estimate camera motion parameter based on invariant point features. Typically, feature information of image has drawbacks, it is variable to camera viewpoint, and therefore information quantity increases after time. The LM(Levenberg-Marquardt) method using nonlinear minimum square evaluation for camera extrinsic parameter estimation also has a weak point, which has different iteration number for approaching the minimal point according to the initial values and convergence time increases if the process run into a local minimum. In order to complement these shortfalls, we, first propose constructing feature models using invariant vector of geometry. Secondly, we propose a two-stage calculation method to improve accuracy and convergence by using homography and LM method. In the experiment, we compare and analyze the proposed method with existing method to demonstrate the superiority of the proposed algorithms.

ALMOST PRETOPOLOGICAL CONVERGENCE SPACES

  • Park, Sang-Ho
    • East Asian mathematical journal
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    • v.18 no.2
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    • pp.211-218
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    • 2002
  • In this paper, we introduce the notion of almost topological convergence spaces and almost pretopological convergence spaces, and prove that these are product invariant.

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IMPROVING THE ORDER AND RATES OF CONVERGENCE FOR THE SUPER-HALLEY METHOD IN BANACH SPACES

  • Argyros, Ioannis-K.
    • Journal of applied mathematics & informatics
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    • v.5 no.2
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    • pp.507-516
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    • 1998
  • In this study we are concerned with the problem of ap-proximating a locally unique solution of an equation on a Banach space. A semilocal convergence theorem is given for the Super-Halley method in Banach spaces. Earlier results have shown that the order of convergence is four for a certain class of operators [4] [5] [8] These results were not given in affine invariant form and made use of a real quadratic majorizing polynomial. Here we provide our re-sults in affine invariant form showing that the order of convergence is at least four. In cases that it is exactly four the rate of convergence is improved. We achieve these results by using a cubic majorizing polynomial. Some numerical examples are given to show that our error bounds are better than earlier ones.

A Study on the Optimum Convergence Factor for Adaptive Filters (적응필터를 위한 최적수렴일자에 관한 연구)

  • 부인형;강철호
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.7
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    • pp.49-57
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    • 1994
  • An efficient approach for the computationtion of the optimum convergence factor is proposed for the LMS algorithm applied to a transversal FIR structure in this study. The approach automatically leads to an optimum step size algorithm at each weight in every iteration that results in a dramatic reduction in terms of convergence time. The algorithm is evaluated in system identification application where two alternative computer simulations are considered for time-invariant and time-varying system cases. The results show that the proposed algorithm needs not appropriate convergence factor and has better performance than AGC(Automatic Gain Control) algorithm and Karni algorithm, which require the convergence factors controlled arbitrarily in computer simulation for time-invariant system and time-varying systems. Also, itis shown that the proposed algorithm has the excellent adaptability campared with NLMS(Normalized LMS) algorithm and RLS (Recursive least Square) algorithm for time-varying circumstances.

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Texture Classification Using Rotation Invariant Local Directional Pattern (Rotation Invariant Local Directional Pattern을 이용한 텍스처 분류 방법)

  • Lee, Tae Hwan;Chae, Ok Sam
    • Convergence Security Journal
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    • v.17 no.3
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    • pp.21-29
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    • 2017
  • Accurate encoding of local patterns is a very important factor in texture classification. However, LBP based methods w idely studied have fundamental problems that are vulnerable to noise. Recently, LDP method using edge response and dire ction information was proposed in facial expression recognition. LDP is more robust to noise than LBP and can accommod ate more information in it's pattern code, but it has drawbacks that it is sensitive to rotation transforms that are critical to texture classification. In this paper, we propose a new local pattern coding method called Rotation Invariant Local Direc tional Pattern, which combines rotation-invariant transform to LDP. To prove the texture classification performance of the proposed method in this paper, texture classification was performed on the widely used UIUC and CUReT datasets. As a result, the proposed RILDP method showed better performance than the existing methods.

Definition and Analysis of Shadow Features for Shadow Detection in Single Natural Image (단일 자연 영상에서 그림자 검출을 위한 그림자 특징 요소들의 정의와 분석)

  • Park, Ki Hong;Lee, Yang Sun
    • Journal of Digital Contents Society
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    • v.19 no.1
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    • pp.165-171
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    • 2018
  • Shadow is a physical phenomenon observed in natural scenes and has a negative effect on various image processing systems such as intelligent video surveillance, traffic surveillance and aerial imagery analysis. Therefore, shadow detection should be considered as a preprocessing process in all areas of computer vision. In this paper, we define and analyze various feature elements for shadow detection in a single natural image that does not require a reference image. The shadow elements describe the intensity, chromaticity, illuminant-invariant, color invariance, and entropy image, which indicate the uncertainty of the information. The results show that the chromaticity and illuminant-invariant images are effective for shadow detection. In the future, we will define a fusion map of various shadow feature elements, and continue to study shadow detection that can adapt to various lighting levels, and shadow removal using chromaticity and illuminance invariant images.

On the Weak Law of Large Numbers for the Sums of Sign-Invariant Random Variables (대칭확률변수(對稱確率變數)의 대수(對數)의 법칙(法則)에 대하여)

  • Hong, Dug-Hun
    • Journal of the Korean Data and Information Science Society
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    • v.4
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    • pp.53-63
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    • 1993
  • We consider various types of weak convergence for sums of sign-invariant random variables. Some results show a similarity between independence and sign-invariance. As a special case, we obtain a result which strengthens a weak law proved by Rosalsky and Teicher [6] in that some assumptions are deleted.

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INVARIANTS WITH RESPECT TO ALL ADMISSIBLE POLAR TOPOLOGIES

  • Cho, Min-Hyung;Hwang, Hong Taek
    • Korean Journal of Mathematics
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    • v.7 no.1
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    • pp.45-51
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    • 1999
  • Let X and Y be topological vector spaces. For a sequence {$T_j$} of bounded operators from X into Y the $c_0$-multiplier convergence of ${\sum}T_j$ is an invariant on topologies which are stronger (need not strictly) than the topology of pointwise convergence on X but are weaker (need not strictly) than the topology of uniform convergence on bounded subsets of X.

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CONCERNING THE RADIUS OF CONVERGENCE OF NEWTON'S METHOD AND APPLICATIONS

  • Argyros, Ioannis K.
    • Journal of applied mathematics & informatics
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    • v.6 no.3
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    • pp.685-696
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    • 1999
  • We present local and semilocal convergence results for New-ton's method in a Banach space setting. In particular using Lipschitz-type assumptions on the second Frechet-derivative we find results con-cerning the radius of convergence of Newton's method. Such results are useful in the context of predictor-corrector continuation procedures. Finally we provide numerical examples to show that our results can ap-ply where earlier ones using Lipschitz assumption on the first Frechet-derivative fail.

Linear Regression-based 1D Invariant Image for Shadow Detection and Removal in Single Natural Image (단일 자연 영상에서 그림자 검출 및 제거를 위한 선형 회귀 기반의 1D 불변 영상)

  • Park, Ki-Hong
    • Journal of Digital Contents Society
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    • v.19 no.9
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    • pp.1787-1793
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    • 2018
  • Shadow is a common phenomenon observed in natural scenes, but it has a negative influence on image analysis such as object recognition, feature detection and scene analysis. Therefore, the process of detecting and removing shadows included in digital images must be considered as a pre-processing process of image analysis. In this paper, the existing methods for acquiring 1D invariant images, one of the feature elements for detecting and removing shadows contained in a single natural image, are described, and a method for obtaining 1D invariant images based on linear regression has been proposed. The proposed method calculates the log of the band-ratio between each channel of the RGB color image, and obtains the grayscale image line by linear regression. The final 1D invariant images were obtained by projecting the log image of the band-ratio onto the estimated grayscale image line. Experimental results show that the proposed method has lower computational complexity than the existing projection method using entropy minimization, and shadow detection and removal based on 1D invariant images are performed effectively.