• Title/Summary/Keyword: hierarchical estimation

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Multi-resolution hierarchical motion estimation in the wavelet transform domain (웨이브렛 변환된 다해상도 영상을 이용한 계층적 움직임 추정)

  • 김진태;장준필;김동욱;최종수
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.8
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    • pp.50-59
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    • 1996
  • In this paper, a new hierarchical motion estiamtion scheme using the wavelet transformed multi-resolution image layers is proposed. Compared with the full search motion estimation method, the existing hierarchical methods remarkably reduce the amount of the computation but their efficiencies are depreciated by the local minima problem. In order to solve the local minima problem, the multi-resolution image layers are composed using the wavelet transform and the number of layers participated in the motion estimation for a block is determined by considering of its low band energy and higher band energy on the first wavelet transformed layer. The ratio between higher band energy and low band energy of each block is evaluated and in the case of the blocks which include relatively large higher band energy, the motion estimation is carried out in the high resolution layer. Otherwise, all layers are used. The final motion vectors are obtained in the first wavelet transformed layer. So less bits for motion vectors are transmitted, and the decomposition of received image using inverse wavelet transform decreases the blocking effect.

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Hierarchical State Estimation in Power System by Modified Fast Decoupled State Estimation Method and System Decomposition (전력계통에서의 수정고속분할 추정법과 계통분할에 의한 계산적 장웅추정에 관한 연구)

  • 김준현;이종범
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.34 no.5
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    • pp.201-209
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    • 1985
  • This paper describes a method for the state estimation by a modified fast decoupled estimation method and system decomposition. The state values are gained by using the weighted least square estimation method, fast decoupled estimation method, and modified fast decoupled estimation method. The estimated values of each method were compared about effectiveness of state values, respectively. This paper investigated the effects of impedance of well-condition or ill-condition into lines. The characteristics of state estimation were gained through hierarchical state estimation. Each method was applied to three model power systems, and, the results of test for the proposed method are given.

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Bayesian Estimation of the Normal Means under Model Perturbation

  • Kim, Dal-Ho;Han, Seung-Cheol
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.3
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    • pp.1009-1019
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    • 2006
  • In this paper, we consider the simultaneous estimation problem for the normal means. We set up the model structure using the several different distributions of the errors for observing their effects of model perturbation for the error terms in obtaining the empirical Bayes and hierarchical Bayes estimators. We compare the performance of those estimators under model perturbation based on a simulation study.

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Bayes Estimation in a Hierarchical Linear Model

  • Park, Kuey-Chung;Chang, In-Hong;Kim, Byung-Hwee
    • Journal of the Korean Statistical Society
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    • v.27 no.1
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    • pp.1-10
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    • 1998
  • In the problem of estimating a vector of unknown regression coefficients under the sum of squared error losses in a hierarchical linear model, we propose the hierarchical Bayes estimator of a vector of unknown regression coefficients in a hierarchical linear model, and then prove the admissibility of this estimator using Blyth's (196\51) method.

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A Study on New Hierarchical Motion Compensation Pyramid Coding (새로운 계층적 이동 보상 피라미드 부호화 방식 연구)

  • 전준현
    • Journal of Broadcast Engineering
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    • v.8 no.2
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    • pp.181-197
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    • 2003
  • Notion Compensation(MC) technique using Sub-Band Coding with the hierarchical structure is efficient to estimate real motion. In the hierarchical pyramid method, low-band MC pyramid method is popular, where the upper layer estimate the glover motion and next lower layer estimate the local motion. The low-band MC pyramid scheme has two problems. First, because the quantization errors at lower layer are accumulated when using coding and quantizing, it is impossible to search the exact Motion Vector(MV) Second, because of the top-down search problem in the hierarchical structure, MV mismatch in upper layer causes serious MV in lower layer So. we propose new hierarchical MC pyramid method based on edge classification. In this Paper, we show that the performance of proposed Pass-band motion compensation pyramid technique is better than low-band motion compensation pyramid. Also, in the pyramid motion estimation, we propose initial MV estimation scheme based on the edge-pattern classification. As a result, we find that PSNR was increased.

A Study on Partial Pattern Estimation for Sequential Agglomerative Hierarchical Nested Model (SAHN 모델의 부분적 패턴 추정 방법에 대한 연구)

  • Jang, Kyung-Won;Ahn, Tae-Chon
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.143-145
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    • 2005
  • In this paper, an empirical study result on pattern estimation method is devoted to reveal underlying data patterns with a relatively reduced computational cost. Presented method performs crisp type clustering with given n number of data samples by means of the sequential agglomerative hierarchical nested model (SAHN). Conventional SAHN based clustering requires large computation time in the initial step of algorithm. To deal with this concern, we modified overall process with a partial approach. In the beginning of this method, we divide given data set to several sub groups with uniform sampling and then each divided sub data group is applied to SAHN based method. The advantage of this method reduces computation time of original process and gives similar results. Proposed is applied to several test data set and simulation result with conceptual analysis is presented.

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Design and Verification of Algorithms for the Motion Detection of Vehicles using Hierarchical Motion Estimation and Parallel Processing (계층화 모션 추정법과 병렬처리 기반의 차량 움직임 측정 알고리즘 개발 및 검증1))

  • 강경훈;심현진;이은숙;정성태;남궁문;금기정;이상설
    • Proceedings of the IEEK Conference
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    • 2002.06d
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    • pp.21-24
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    • 2002
  • This paper presents a new method for the motion detection of vehicles using hierarchical motion estimation and parallel processing. It captures the road image by using a CMOS sensor. It divides the captured image into small blocks and detects the motion of each block by using a block-matching method which is based on a hierarchical motion estimation and parallel processing for the real-time processing. The parallelism is achieved by using the pipeline and the data flow technique. The proposed method has been implemented with an embedded system. Experimental results show that the proposed method detects the motion of vehicles in real-time.

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A Fast Hierarchical Motion Vector Estimation Using Mean Pyramids (평균 피라미드를 이용한 계층적 고속 이동벡터 추정)

  • 남권문;김준식;박래홍;심영석
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.6
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    • pp.35-48
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    • 1993
  • In this paper, a hierarchical motion vector estimation algorithm using pyramidal structure is proposed. Using a smaller measurement window at each level of a pyramid than that of the conventional scheme, the proposed algorithm, based on the TSS(three step search), reduces the computational complexity greatly with its performance comparable to that of the TSS. By increasing the number of cnadidate motion vectors which are to be used as the initial search points for motion vector estimation at the next level, the performance improves further. Then the computational complexity of the proposed hierarchical algorithm depends on the number of candidate motion vectors, with its PSNR (peak signal to noise ratio) ranging between those of the TSS and the full search method. The simulation results with two different block sizes and various test sequences are given and its hardware implementation is also sketched.

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A Hierarchical Motion Estimation Algorithm Using Correlation of Motion Fields

  • Song, B.C.;Lim, K.W.;J.B.Ra
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1996.06b
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    • pp.41-44
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    • 1996
  • A new three step hierarchical search algorithm for motion estimation is proposed. The proposed algorithm exploits the motion correlation of spatially neighboring blocks and the motion continuity of temporally neighboring blocks to alleviate the local minimum problem in the first step of the three step hierarchical search algorithm (3SHS). Simulation results show that the proposed scheme achieves significant improvements in both estimation accuracy and performance reliability compared with the existing fast block matching algorithm including 3SHS, while maintaining almost the same computational complexity as 3SHS. The proposed scheme also possesses the regularity and simplicity of hardware-oriented features.

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Hierarchical Bayes Estimators of the Error Variance in Two-Way ANOVA Models

  • Chang, In Hong;Kim, Byung Hwee
    • Communications for Statistical Applications and Methods
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    • v.9 no.2
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    • pp.315-324
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    • 2002
  • For estimating the error variance under the relative squared error loss in two-way analysis of variance models, we provide a class of hierarchical Bayes estimators and then derive a subclass of the hierarchical Bayes estimators, each member of which dominates the best multiple of the error sum of squares which is known to be minimax. We also identify a subclass of non-minimax hierarchical Bayes estimators.