• Title/Summary/Keyword: descriptor

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MPEG-7 Homogeneous Texture Descriptor

  • Ro, Yong-Man;Kim, Mun-Churl;Kang, Ho-Kyung;Manjunath, B.S.;Kim, Jin-Woong
    • ETRI Journal
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    • v.23 no.2
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    • pp.41-51
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    • 2001
  • MPEG-7 standardization work has started with the aims of providing fundamental tools for describing multimedia contents. MPEG-7 defines the syntax and semantics of descriptors and description schemes so that they may be used as fundamental tools for multimedia content description. In this paper, we introduce a texture based image description and retrieval method, which is adopted as the homogeneous texture descriptor in the visual part of the MPEG-7 final committee draft. The current MPEG-7 homogeneous texture descriptor consists of the mean, the standard deviation value of an image, energy, and energy deviation values of Fourier transform of the image. These are extracted from partitioned frequency channels based on the human visual system (HVS). For reliable extraction of the texture descriptor, Radon transformation is employed. This is suitable for HVS behavior. We also introduce various matching methods; for example, intensity-invariant, rotation-invariant and/or scale-invariant matching. This technique retrieves relevant texture images when the user gives a querying texture image. In order to show the promising performance of the texture descriptor, we take the experimental results with the MPEG-7 test sets. Experimental results show that the MPEG-7 texture descriptor gives an efficient and effective retrieval rate. Furthermore, it gives fast feature extraction time for constructing the texture descriptor.

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The model following control systems for descriptor system

  • Tang, Houjun;Okubo, Shigenori
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.372-375
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    • 1996
  • In this paper, a designing method of model following control system for linear descriptor system with disturbances is proposed. The features of this method are:1) both the physical structure of the system and the physical system variables properties can be preserved because there is no necessary to make transformation of this system. 2) boundedness of internal states are proved by means of coprime factorization of descriptor system.

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Algebraic Observer Design for Descriptor Systems via Block-pulse Function Expansions (블록펄스함수 전개를 이용한 Descriptor 시스템의 대수적 관측기 설계)

  • 안비오
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.50 no.6
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    • pp.259-265
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    • 2001
  • In the last two decades, many researchers proposed various usages of the orthogonal functions such as Walsh, Haar and BPF to solve the system analysis, optimal control, and identification problems from and algebraic form. In this paper, a simple procedure to design and algerbraic observer for the descriptor system is presented by using block pulse function expansions. The main characteristic of this technique is that it converts differential observer equation into an algerbraic equation. And furthermore, a simple recursive algorithm is proposed to obtain BPFs coefficients of the observer equation.

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A Study on Intelligent Decentralized Active Suspension Control System with Descriptor LMI Design Method

  • Park, Jung-Hyen
    • Journal of information and communication convergence engineering
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    • v.6 no.2
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    • pp.198-203
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    • 2008
  • An Intelligent optimal control system design algorithm in active suspension equipment adopting linear matrix inequalities control system design theory with representing by descriptor system form is presented. The validity of the linear matrix inequalities intelligent decentralized control system design with representing by descriptor system form in active suspension system through the numerical examples is also investigated.

Selecting a Composite of MPEG-7 Visual Descriptor by KLT Algorithm (KLT 알고리즘을 사용한 MPEG-7의 최적Descriptor 조합선택에 관한 연구)

  • 김현민;권기상;권혁민;최윤식
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.1831-1834
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    • 2003
  • Due to the increasing of multimedia data quantity, database searching based on image becomes important. For this scheme, MPEG-7 gives a good solution to efficient data searching. MPEG-7 uses Descriptors which are color, texture, and shape to extract features from images. It is obvious that using more than one Descriptor causes more accurate data searching result than using just one. In this paper, selecting a composite of MPEG-7 visual Descriptor using KL-Expansion is proposed.

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THE EXISTENCE OF SOLUTIONS OF LINEAR MULTIVARIABLE SYSTEMS IN DESCRIPTOR FROM FORM

  • AASARAAI, A.
    • Honam Mathematical Journal
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    • v.24 no.1
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    • pp.35-41
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    • 2002
  • The solutions of a homogeneous system in state space form $\dot{x}=Ax$ are to the form $x=e^{At}x_0$ and the solutions of an inhomogeneous system $\dot{x}=Ax(t)+f(t)$ are to the form $x=e^{At}x_0+{{\int}_0^t}\;e^{A(t-{\tau})}f({\tau})d{\tau}$. In this note we show that the solution of descriptor systems under some conditions exists, and is unique, moreover it is interesting to know the solutions of descriptor system are schematically like the solutions as in the state space form. Also we will give some algorithms to compute these solutions.

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Region-based Shape Descriptor with Moving a Vision Center for Image Representation (영상표현을 위한 비전 중심점 이동에 따른 영역기반 형태 기술자)

  • Kim Seon-Jong;Kim Young-In
    • Journal of Intelligence and Information Systems
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    • v.12 no.1
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    • pp.95-105
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    • 2006
  • This paper proposes a novel approach to represent the image by using shape descriptor having an information of area. The proposed descriptor is a set of vectors, consists of radius, area and direction parameters in the concentrated center point. Due to the area parameter, we know our descriptor can obtain the information of area. Also, we give an extended shape descriptor to get more detailed representation. To do this, we move the center point of our vision to that point for region of interest. By doing so about all of region of interest, we can get our descriptor for detailed information of the image. From more detailed descriptor, it's natural that it's more efficient fur representation, retrievals and so on. We make it the normalized pattern and expand to improve its quality. The proposed method is invariant to scale, position and rotation. The results show that it can be used efficiently for image representation as we can see in retrievals of silhouette images.

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Fixed-Order $H_{\infty}$ Controller Design for Descriptor Systems

  • Zhai, Guisheng;Yoshida, Masaharu;Koyama, Naoki
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.898-902
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    • 2003
  • For linear descriptor systems, we consider the $H_{INFTY}$ controller design problem via output feedback. Both static output feedback and dynamic one are discussed. First, in the case of static output feedback, we reduce our control problem to solving a bilinear matrix inequality (BMI) with respect to the controller coefficient matrix, a Lyapunov matrix and a matrix related to the descriptor matrix. Under a matching condition between the descriptor matrix and the measured output matrix (or the control input matrix), we propose setting the Lyapunov matrix in the BMI as being block diagonal appropriately so that the BMI is reduced to LMIs. For fixed-order dynamic $H_{INFTY}$ output feedback, we formulate the control problem equivalently as the one of static output feedback design, and thus the same approach can be applied.

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PPD: A Robust Low-computation Local Descriptor for Mobile Image Retrieval

  • Liu, Congxin;Yang, Jie;Feng, Deying
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.3
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    • pp.305-323
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    • 2010
  • This paper proposes an efficient and yet powerful local descriptor called phase-space partition based descriptor (PPD). This descriptor is designed for the mobile image matching and retrieval. PPD, which is inspired from SIFT, also encodes the salient aspects of the image gradient in the neighborhood around an interest point. However, without employing SIFT's smoothed gradient orientation histogram, we apply the region based gradient statistics in phase space to the construction of a feature representation, which allows to reduce much computation requirements. The feature matching experiments demonstrate that PPD achieves favorable performance close to that of SIFT and faster building and matching. We also present results showing that the use of PPD descriptors in a mobile image retrieval application results in a comparable performance to SIFT.

MEGH: A New Affine Invariant Descriptor

  • Dong, Xiaojie;Liu, Erqi;Yang, Jie;Wu, Qiang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.7
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    • pp.1690-1704
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    • 2013
  • An affine invariant descriptor is proposed, which is able to well represent the affine covariant regions. Estimating main orientation is still problematic in many existing method, such as SIFT (scale invariant feature transform) and SURF (speeded up robust features). Instead of aligning the estimated main orientation, in this paper ellipse orientation is directly used. According to ellipse orientation, affine covariant regions are firstly divided into 4 sub-regions with equal angles. Since affine covariant regions are divided from the ellipse orientation, the divided sub-regions are rotation invariant regardless the rotation, if any, of ellipse. Meanwhile, the affine covariant regions are normalized into a circular region. In the end, the gradients of pixels in the circular region are calculated and the partition-based descriptor is created by using the gradients. Compared with the existing descriptors including MROGH, SIFT, GLOH, PCA-SIFT and spin images, the proposed descriptor demonstrates superior performance according to extensive experiments.