• Title/Summary/Keyword: invariant

Search Result 2,151, Processing Time 0.031 seconds

Face Recognition Robust to Pose Variations (포즈 변화에 강인한 얼굴 인식)

  • 노진우;문인혁;고한석
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.41 no.5
    • /
    • pp.63-69
    • /
    • 2004
  • This paper proposes a novel method for achieving pose-invariant face recognition using cylindrical model. On the assumption that a face is shaped like that of a cylinder, we estimate the object's pose and then extract the frontal face image via a pose transform with previously estimated pose angle. By employing the proposed pose transform technique we can increase the face recognition performance using the frontal face images. Through representative experiments, we achieved an increased recognition rate from 61.43% to 94.76% by the pose transform. Additionally, the recognition rate with the proposed method achieves as good as that of the more complicated 3D face model.

Object-based Image Restoration Method for Enhancing Motion Blurred Images (움직임열화를 갖는 영상의 화질개선을 위한 객체기반 영상복원기법)

  • Choung, Yoo-Chan;Paik, Joon-Ki
    • Journal of the Korean Institute of Telematics and Electronics S
    • /
    • v.35S no.12
    • /
    • pp.77-83
    • /
    • 1998
  • Generally a moving picture suffers from motion blur, due to relative motion between moving objects and the image formation system. The purpose of this paper is to propose teh model for the motion blur and the restoration method using the regularized iterative technique. In the proposed model, the boundary effect between moving objects and background is analyzed mathematically to overcome the limit of the spatially invariant model. And we present the motion-based image segmentation technique for the object-based image restoration, which is the modified version of the conventional segmentation method. Based on the proposed model, the restoration technique removes the motion blur by using the estimated motion parameter from the result of the segmentation.

  • PDF

The Design of Multi-Objective $H_2/H_{\infty}$ Controllers for multiple linear Time-invariant models (다중 선형 시불변 모델에 대한 다목적 $H_2/H_{\infty}$ 제어기 설계)

  • Cho, Do-Hyeoun;Won, Young-Jin;Lee, Jong-Yong
    • Journal of the Institute of Electronics Engineers of Korea TE
    • /
    • v.42 no.3
    • /
    • pp.13-18
    • /
    • 2005
  • This paper presents a design of a multi-objective $H_2/H_{\infty}$ controller of an inverted pendulum with polytopic model by the stabilizing regulator and tracking performances. Multi-objective controllers are designed for polytopic models by the LMI design technique with convex algorithms. It is observed that the inverted pendulum controlled by any controller designed for each polytopic model is stably restored to the vertical angle position for initial values of larger tilt angles.

Realistic Reliability Analysis of Reinforced Concrete Structures (철근콘크리트 구조물의 합리적인 신뢰성해석연구)

  • Oh, Byung Hwan;Koh, Chae Koon;Baik, Shin Won;Lee, Hyung Joon;Han, Seung Hwan
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.13 no.2
    • /
    • pp.121-133
    • /
    • 1993
  • Presented is a study on the establishment of a method of advanced reliability analysis for the realistic analysis and design of reinforced concrete(RC) structures. Considerable variabilities exist in concrete structures due to random nature of concrete materials and member dimensions. The present study analyzes first the uncertainties in concrete, reinforcements and member dimensions and then a method is proposed to determine the probability uncertainties of basic variables. The limit state equations are also proposed for the RC members with axial compression and bending and RC footings. The advanced invariant second-moment method is applied to analyze those structures. The present study provides an important base for realistic reliability analysis of RC structures.

  • PDF

Prediction of the Radiated Noise from the Vehicle Intake System (자동차 흡기계의 방사소음 예측에 대한 연구)

  • Kim, Hoi-Jeon;Ih, Jeong-Guon;Lee, Seong-Hyun;Shinoda, K.;Kitahara, S.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2005.11b
    • /
    • pp.105-108
    • /
    • 2005
  • The radiated noise from the automotive intake system should be predicted at the design stage. To this end, the precise measurement of in-duct acoustic source parameters of the intake system, i.e., the source strength and source impedance, is essential. Most of previous works on the measurement of acoustic source parameters were performed under a fixed engine speed condition. However, the requirement of vehicle manufacturer is the noise radiation pattern as a function of engine speed. In this study, the direct method was employed to measure the source parameters of engine intake system under a fixed engine speed and engine run-up condition. It was noted that the frequency spectra of source impedance hardly changes with varying the engine speed. Thus, it is reasonable to calculate the source strength under the engine run-up condition by assuming that source impedance is invariant with engine speed. Measured and conventional source models, i.e., constant pressure source, constant velocity source, and non-reflective source, were utilized to predict insertion loss and radiated sound pressure level. A reasonable prediction accuracy of radiated sound pressure level spectra from the intake system was given in the test vehicle when using the measured source characteristics which were acquired under the operating condition.

  • PDF

RINGS WITH REFLEXIVE IDEALS

  • Han, Juncheol;Park, Sangwon
    • East Asian mathematical journal
    • /
    • v.34 no.3
    • /
    • pp.305-316
    • /
    • 2018
  • Let R be a ring with identity. A right ideal ideal I of a ring R is called ref lexive (resp. completely ref lexive) if $aRb{\subseteq}I$ implies that $bRa{\subseteq}I$ (resp. if $ab{\subseteq}I$ implies that $ba{\subseteq}I$) for any $a,\;b{\in}R$. R is called ref lexive (resp. completely ref lexive) if the zero ideal of R is a reflexive ideal (resp. a completely reflexive ideal). Let K(R) (called the ref lexive radical of R) be the intersection of all reflexive ideals of R. In this paper, the following are investigated: (1) Some equivalent conditions on an reflexive ideal of a ring are obtained; (2) reflexive (resp. completely reflexive) property is Morita invariant; (3) For any ring R, we have $K(M_n(R))=M_n(K(R))$ where $M_n(R)$ is the ring of all n by n matrices over R; (4) For a ring R, we have $K(R)[x]{\subseteq}K(R[x])$; in particular, if R is quasi-Armendaritz, then R is reflexive if and only if R[x] is reflexive.

A Subsequence Matching Technique that Supports Time Warping Efficiently (타임 워핑을 지원하는 효율적인 서브시퀀스 매칭 기법)

  • Park, Sang-Hyun;Kim, Sang-Wook;Cho, June-Suh;Lee, Hoen-Gil
    • Journal of Industrial Technology
    • /
    • v.21 no.A
    • /
    • pp.167-179
    • /
    • 2001
  • This paper discusses an index-based subsequence matching that supports time warping in large sequence databases. Time warping enables finding sequences with similar patterns even when they are of different lengths. In earlier work, we suggested an efficient method for whole matching under time warping. This method constructs a multidimensional index on a set of feature vectors, which are invariant to time warping, from data sequences. For filtering at feature space, it also applies a lower-bound function, which consistently underestimates the time warping distance as well as satisfies the triangular inequality. In this paper, we incorporate the prefix-querying approach based on sliding windows into the earlier approach. For indexing, we extract a feature vector from every subsequence inside a sliding window and construct a multi-dimensional index using a feature vector as indexing attributes. For query precessing, we perform a series of index searches using the feature vectors of qualifying query prefixes. Our approach provides effective and scalable subsequence matching even with a large volume of a database. We also prove that our approach does not incur false dismissal. To verily the superiority of our method, we perform extensive experiments. The results reseal that our method achieves significant speedup with real-world S&P 500 stock data and with very large synthetic data.

  • PDF

Object Retrieval Using the Corners Area Variability Based on Correlogram (코너영역 분산치 기반 코렐로그램을 이용한 형태검출)

  • An, Young-Eun;Lee, Ji-Min;Yang, Won-Ii;Choi, Young-Il;Chang, Min-Hyuk
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.11 no.6
    • /
    • pp.283-288
    • /
    • 2011
  • This paper have proposed an object retrieval using the corners area variability based on correlogram. The proposed algorithm is processed as follows. First, the corner points of the object in an image are extracted and then the feature vectors are obtained. It are rearranged according to the number dimension and consist of sequence vectors. And the similarity based on the maximum of sequence vectors is measured. The proposed technique is invariant to the rotation or the transfer of the objects and more efficient in case that the objects present simple structure. In simulation that use Wang's database, the method presents that the recall property is improved by 0.03% and more than the standard corner patch histogram.

Some Properties of Complex Grassmann Manifolds

  • Kim, In-Su
    • Honam Mathematical Journal
    • /
    • v.5 no.1
    • /
    • pp.45-69
    • /
    • 1983
  • The hermitian structures on complex manifolds have been studied by several mathematicians ([1], [2], and [3]), and the Kähler structure on hermitian manifolds have been so much too ([6], [12], and [15]). There has been some gradual progress in studying the invariant forms on Grassmann manifolds ([17]). The purpose of this dissertation is to prove the Theorem 3.4 and the Theorem 4.7, with relation to the nature of complex Grassmann manifolds. In $\S$ 2. in order to prove the Theorem 4.7, which will be explicated further in $\S$ 4, the concepts of the hermitian structure, connection and curvature have been defined. and the characteristic nature about these were proved. (Proposition 2.3, 2.4, 2.9, 2.11, and 2.12) Two characteristics were proved in $\S$ 3. They are almost not proved before: particularly. we proved the Theorem 3.3 : $G_{k}(C^{n+k})=\frac{GL(n+k,C)}{GL(k,n,C)}=\frac{U(n+k)}{U(k){\times}U(n)}$ In $\S$ 4. we explained and proved the Theorem 4. 7 : i) Complex Grassmann manifolds are Kahlerian. ii) This Kähler form is $\pi$-fold of curvature form in hyperplane section bundle. Prior to this proof. some propositions and lemmas were proved at the same time. (Proposition 4.2, Lemma 4.3, Corollary 4.4 and Lemma 4.5).

  • PDF

An Efficient Partial Matching System and Region-based Representation for 2D Images (2D 영상의 효과적인 부분 정합 시스템과 영역기반 영상 표현)

  • Kim, Seon-Jong
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.13 no.9
    • /
    • pp.868-874
    • /
    • 2007
  • This paper proposes an efficient partial matching system and representation by using a region-based method for 2D image, and we applied to an extraction of the ROI(Region of Interest) according to its matching score. The matching templates consist of the global pattern and the local one. The global pattern can make it by using region-based relation between center region and its rest regions in an object. And, the local pattern can be obtained appling to the same method as global, except relation between objects. As the templates can be normalized, we use this templates for extraction of ROI with invariant to size and position. And, our system operates only one try to match, due to normalizing of region size. To use our system for searching and examining if it's the ROI by evaluating the matching function, at first, we are searching to find candidate regions with the global template. Then, we try to find the ROI among the candidates, and it works this time by using the local template. We experimented to the binary and the color image respectively, they showed that the proposed system can be used efficiently for representing of the template and the useful applications, such as partially retrievals of 2D image.