• Title/Summary/Keyword: descriptor analysis

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A Survey of Shape Descriptors in Computer Vision (컴퓨터비전에서 사용되는 모양표시자의 현황)

  • 유헌우;장동식
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.2
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    • pp.131-139
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    • 2003
  • Shape descriptors play an important role in systems for object recognition, retrieval, registration, and analysis. Seven well-known descriptors including MPEG-7 visual descriptors arebriefly reviewed and a new robust pattern recognition descriptor is proposed. Performance comparison among descriptors are presented. Experiments show that the newly proposed descriptor yields better performance results than Fourier, invariant moment, and edge histogram descriptors.

Stability Analysis of Descriptor System Using Generalized Lyapunov Equation (일반화된 Lyapunov 방정식을 이용한 descriptor 시스템의 안정석 해석)

  • Oh, Do-Chang;Lee, Dong-Gi
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.46 no.4
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    • pp.49-57
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    • 2009
  • In this paper we consider the specific types of the generalized continuous-time Lyapunov equation and the existence of solution. This is motivated to analyze the system stability in situations where descriptor system has infinite eigenvalue. As main results, firstly the necessary and sufficient condition for stability of the descriptor system with index one or two will be proposed. Secondly, for the general case of any index, the similar condition for stability of descriptor system will be proposed with the specific type of the generalized Lyapunov equation. Finally some examples are used to show the validity of proposed methods.

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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Hybrid Facial Representations for Emotion Recognition

  • Yun, Woo-Han;Kim, DoHyung;Park, Chankyu;Kim, Jaehong
    • ETRI Journal
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    • v.35 no.6
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    • pp.1021-1028
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    • 2013
  • Automatic facial expression recognition is a widely studied problem in computer vision and human-robot interaction. There has been a range of studies for representing facial descriptors for facial expression recognition. Some prominent descriptors were presented in the first facial expression recognition and analysis challenge (FERA2011). In that competition, the Local Gabor Binary Pattern Histogram Sequence descriptor showed the most powerful description capability. In this paper, we introduce hybrid facial representations for facial expression recognition, which have more powerful description capability with lower dimensionality. Our descriptors consist of a block-based descriptor and a pixel-based descriptor. The block-based descriptor represents the micro-orientation and micro-geometric structure information. The pixel-based descriptor represents texture information. We validate our descriptors on two public databases, and the results show that our descriptors perform well with a relatively low dimensionality.

A study of optimal MPEG-7 descriptor composite in database searching using PCA (PCA를 이용한 데이터베이스 검색에 있어서의 최적 MPEG-7 디스크립터 조합에 관한 연구)

  • 김현민;최윤식
    • Proceedings of the IEEK Conference
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    • 2003.11a
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    • pp.437-440
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    • 2003
  • When we search database with a query image, the retrieval efficiency will vary from each kind of descriptor. Even the best representative descriptor, it results a few useless images that don't match with query image. This type of error can be reduced by adopting another descriptor which extracts features in different way. At present, the choice of descriptors is base on intuitive and experimental method. By theoretic accessing to the problem of descriptor choice, we can solve the given problem in the objective and rational way. In this study, we intend to make a composite of descriptors that can reduce retrieval error by adopting principal component analysis.

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Efficient Representation and Matching of Object Movement using Shape Sequence Descriptor (모양 시퀀스 기술자를 이용한 효과적인 동작 표현 및 검색 방법)

  • Choi, Min-Seok
    • The KIPS Transactions:PartB
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    • v.15B no.5
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    • pp.391-396
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    • 2008
  • Motion of object in a video clip often plays an important role in characterizing the content of the clip. A number of methods have been developed to analyze and retrieve video contents using motion information. However, most of these methods focused more on the analysis of direction or trajectory of motion but less on the analysis of the movement of an object itself. In this paper, we propose the shape sequence descriptor to describe and compare the movement based on the shape deformation caused by object motion along the time. A movement information is first represented a sequence of 2D shape of object extracted from input image sequence, and then 2D shape information is converted 1D shape feature using the shape descriptor. The shape sequence descriptor is obtained from the shape descriptor sequence by frequency transform along the time. Our experiment results show that the proposed method can be very simple and effective to describe the object movement and can be applicable to semantic applications such as content-based video retrieval and human movement recognition.

Application of Molecular Descriptor for Prediction and Analysis of the Affinity between Alkyl Substituted Super Hydrophobic Dyes and Polypropylene Fibers (폴리프로필렌 섬유용 알킬치환 초소수성 염료의 친화력 분석과 예측을 위한 Molecular Descriptor의 활용)

  • Jang, Gyeong-Jin;Jeong, Jong-Seok;Kim, Tae-Gyeong
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2008.10a
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    • pp.77-78
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    • 2008
  • Affinity between alkyl substituted super hydrophobic dyes and polypropylene fiber has been analyzed by using the molecular descriptor as a method to predict chemical and physical characteristics of compounds. Hydrophobicity of synthesized dyes calculated by LogP which is one of molecular descriptors was increased continuously as the length of alkyl substituents increased.

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Delay-Dependent Control for Time-Delayed T-S Fuzzy Systems Using Descriptor Representation

  • Jeung, Eun-Tae;Oh, Do-Chang;Park, Hong-Bae
    • International Journal of Control, Automation, and Systems
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    • v.2 no.2
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    • pp.182-188
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    • 2004
  • This paper presents a design method of delay-dependent control for T-S fuzzy systems with time delays. Based on parallel distributed compensation (PDC) and a descriptor model transformation of the system, a delay-dependent control is utilized. An appropriate Lyapunov-Krasovskii functional is chosen for delay-dependent stability analysis. A sufficient condition for delay-dependent control is represented in terms of linear matrix inequalities (LMIs).

Analysis on Particle Shape Characteristics of Jumunjin Sand using Fourier Descriptor (Fourier descriptor를 이용한 주문진표준사의 형상특성분석)

  • Min, Tuk-Ki;Kim, Seong-Gon
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09a
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    • pp.1182-1189
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    • 2010
  • The mechanical behavior of a granular material is governed by the applying effective stresses and its skeletal structure which is considered to be the packing of particles giving overall density and degree of anisotropic. Factors that affect soil packing are the particle size, size distribution and shape, and the arrangement of grain contact. Soil particle size and shape are the most important factor, but difficult to quantify. In this study, 2D Fourier analysis is applied to quantify the shape of granular particles. Jumunjin sand was used in the experiment and particle images are captured using an optical microscope. The results showed that three lower order Fourier descriptor are closely related with roundness, sphericity of the granular particle. Also statistical approach is used to determine roundness, form factor, elongation ratio, roughness of Jumunjin sand.

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Content-Based Retrieval using MPEG-7 Visual Descriptor and Hippocampal Neural Network (MPEG-7 시각 기술자와 해마 신경망을 이용한 내용기반 검색)

  • Kim Young Ho;Kang Dae-Seong
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.12
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    • pp.1083-1087
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    • 2005
  • As development of digital technology, many kinds of multimedia data are used variously and requirements for effective use by user are increasing. In order to transfer information fast and precisely what user wants, effective retrieval method is required. As existing multimedia data are impossible to apply the MPEG-1, MPEG-2 and MPEG-4 technologies which are aimed at compression, store and transmission. So MPEG-7 is introduced as a new technology for effective management and retrieval of multimedia data. In this paper, we extract content-based features using color descriptor among the MPEG-7 standardization visual descriptor, and reduce feature data applying PCA(Principal Components Analysis) technique. We model the cerebral cortex and hippocampal neural network in engineering domain, and team content-based feature vectors fast and apply the hippocampal neural network algorithm to compose of optimized feature. And then we present fast and precise retrieval effect when indexing and retrieving.