• 제목/요약/키워드: A. affine

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영상 전송을 위한 어핀변환 부호화 (Affine Transform Coding for Image Transmission)

  • 김정일
    • 한국컴퓨터정보학회논문지
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    • 제4권2호
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    • pp.135-140
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    • 1999
  • 본 논문은 영상 부호화시에 걸리는 오랜 시간을 줄이기 위해 스케일링 방식과 탐색영역 제한방식을 이용한 어핀변환 부호화 방식을 제안한다. 제안한 방법의 성능을 평가하기 위해, 제안한 알고리즘과 전통적인 어핀변환 부호화 방식을 사용하는 Jacquin의 방법과 비교하였다. 시뮬레이션 결과, 제안한 알고리즘은 스케일링 방식과 탐색영역 제한 방식을 사용하므로써, 부호화 시간을 상당히 줄일 수 있었다. Jacquin의 방식과 비교해, 복원된 영상의 화질은 약간 저하되었지만 부호화 시간을 많이 단축하였다.

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Novel View Generation Using Affine Coordinates

  • Sengupta, Kuntal;Ohya, Jun
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 1997년도 Proceedings International Workshop on New Video Media Technology
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    • pp.125-130
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    • 1997
  • In this paper we present an algorithm to generate new views of a scene, starting with images from weakly calibrated cameras. Errors in 3D scene reconstruction usually gets reflected in the quality of the new scene generated, so we seek a direct method for reprojection. In this paper, we use the knowledge of dense point matches and their affine coordinate values to estimate the corresponding affine coordinate values in the new scene. We borrow ideas from the object recognition literature, and extend them significantly to solve the problem of reprojection. Unlike the epipolar line intersection algorithms for reprojection which requires at least eight matched points across three images, we need only five matched points. The theory of reprojection is used with hardware based rendering to achieve fast rendering. We demonstrate our results of novel view generation from stereopairs for arbitrary locations of the virtual camera.

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FIR MIMO 시스템을 위한 부밴드 적응 블라인드 등화 알고리즘 (A Subband Adaptive Blind Equalization Algorithm for FIR MIMO Systems)

  • 손상욱;임영빈;최훈;배현덕
    • 전기학회논문지
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    • 제59권2호
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    • pp.476-483
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    • 2010
  • If the data are pre-whitened, then gradient adaptive algorithms which are simpler than higher order statistics algorithms can be used in adaptive blind signal estimation. In this paper, we propose a blind subband affine projection algorithm for multiple-input multiple-output adaptive equalization in the blind environments. All of the adaptive filters in subband affine projection equalization are decomposed to polyphase components, and the coefficients of the decomposed adaptive sub-filters are updated by defining the multiple cost functions. An infinite impulse response filter bank is designed for the data pre-whitening. Pre-whitening procedure through subband filtering can speed up the convergence rate of the algorithm without additional computation. Simulation results are presented showing the proposed algorithm's convergence rate, blind equalization and blind signal separation performances.

Piecewise Affine Control Design for Power Factor Correction Rectifiers

  • Tahami, Farzad;Poshtkouhi, Shahab;Ahmadian, Hamed Molla
    • Journal of Power Electronics
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    • 제11권3호
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    • pp.327-334
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    • 2011
  • Single-phase power factor correction (PFC) converter circuits are non-linear systems due to the contribution of their multiplier. This non-linearity causes difficulties in analysis and design. Models that reduce the system to a linear system involve considerable approximation, and produce results that are susceptible to instability problems. In this paper a piecewise affine (PWA) system is introduced for describing the nonlinear averaged model. Then robust output feedback controllers are established in terms of the linear matrix inequality (LMI). Simulation and experiments results show the effectiveness of the proposed control method.

컴퓨터 연산을 통한 언어형 퍼지 제어 시스템의 새로운 안정도 해석: 1부 - 퍼지 시스템의 어핀 모델링 (A new computational approach to stability analysis of linguistic fuzzy control systems - Part l: Affine modeling of fuzzy system)

  • 김은태;박순형;박민용
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(3)
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    • pp.169-172
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    • 2001
  • In recent years, many studies regarding the modeling of fuzzy system have been conducted. In this paper, a new computational approach to modeling of linguistic fuzzy system is proposed The fuzzy system is modeled as a combination of affine systems, The proposed method can be used in a rigorous stability analysis of fuzzy system including the linguistic fuzzy controller.

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A MODIFIED INEXACT NEWTON METHOD

  • Huang, Pengzhan;Abduwali, Abdurishit
    • Journal of applied mathematics & informatics
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    • 제33권1_2호
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    • pp.127-143
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    • 2015
  • In this paper, we consider a modified inexact Newton method for solving a nonlinear system F(x) = 0 where $F(x):R^n{\rightarrow}R^n$. The basic idea is to accelerate convergence. A semi-local convergence theorem for the modified inexact Newton method is established and an affine invariant version is also given. Moreover, we test three numerical examples which show that the modified inexact scheme is more efficient than the classical inexact Newton strategy.

REPRESENTATIONS OF U3,6 AND AG(2, 3)

  • Ahn, Seung-Ho;Han, Boong-Bi
    • 호남수학학술지
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    • 제33권3호
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    • pp.381-391
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    • 2011
  • One of the main interesting things of a matroid theory is the representability by a matroid from a matrix over some field F. The representability of uniform matroid $U_{m,n}$ over some field are studied by many authors. In this paper we construct a matrix representing $U_{3,6}$ over the field GF(4). Also we find out matrix of the affine matroid AG(2, 3) over the field GF(4).

A NOTE ON THE ROOT SPACES OF AFFINE LIE ALGEBRAS OF TYPE $D_{\iota}^{(1)}$

  • KIM YEONOK
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제12권1호
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    • pp.65-73
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    • 2005
  • Let g = g(A) = (equation omitted) + be a symmetrizable Kac-Moody Lie algebra of type D/sub l//sup (1) with W as its Weyl group. We construct a sequence of root spaces with certain conditions. We also find the number of terms of this sequence is less then or equal to the hight of θ, the highest root.

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애핀법에 있어서 문제 축소를 위한 최적비기저의 결정 방법 (A Method Identifying the Optimal Nonbasic Columns for the Problem Size Reduction in Affine Scaling Algorithm)

  • 주종혁;박순달
    • 한국경영과학회지
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    • 제17권3호
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    • pp.59-65
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    • 1992
  • A modified primal-dual affine scaling algorithm for linear programming is presented. This modified algorithm generates an elipsoid containing all optimal dual solutions at each iteration, then checks whether or not a dual hyperplane intersects this ellipsoid. If the dual hyperplane has no intersection with this ellipsoid, its corresponding column must be optimal nonbasic. By condensing these columns, the size of LP problem can be reduced.

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Performance Improvement of Acoustic Echo Cancellers Using Delayless Subband Adaptive Filters And Fast Affine Projection Algorithm

  • Ahn, Kyung-Seung
    • The Journal of the Acoustical Society of Korea
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    • 제17권2E호
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    • pp.3-9
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    • 1998
  • Since the introduction of hands-free phone set and teleconferencing system, acoustic echo cancellation has been a challenge for engineers. Recently many researches have shown that the best solution for the acoustic echo compensation problem is represented by an adaptive filter which iteratively tries to identify the unknown impulse response of the system from loudspeaker to microphone. In this paper, we apply the delayless subband adaptive filters and fast affine projection algorithm for the identification of room impulse response. Simulation results show 3∼8 dB more enhanced performance than conventional fullband adaptive filters or subband adaptive filters. In addition, fast affine projection algorithm shows better convergence speed at the expense of the low computational complexity than conventional LMS algorithm.

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