• 제목/요약/키워드: Gaussian elimination

검색결과 48건 처리시간 0.033초

Low Complexity Ordered Successive Cancellation Algorithm for Multi-user STBC Systems

  • Le, Van-Hien;Yang, Qing-Hai;Kwak, Kyung-Sup
    • 한국통신학회논문지
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    • 제32권2A호
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    • pp.162-168
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    • 2007
  • This paper proposes two detection algorithms for Multi-user Space Time Block Code systems. The first one is linear detection Gaussian Elimination algorithm, and then it combined with Ordered Successive Cancellation to get better performance. The comparisons between receiver and other popular receivers, including linear receivers are provided. It will be shown that the performance of Gaussian Elimination receiver is similar but more simplicity than linear detection algorithms and performance of Gaussian Elimination Ordered Successive Cancellation superior as compared to other linear detection method.

Direct Methods for Linear System on Distributed Memory Parallel Computers

  • Nishimura, S.;Shigehara, T.;Mizoguchi, H.;Mishima, T.;Kobayashi, H.
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 ITC-CSCC -1
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    • pp.333-336
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    • 2000
  • We discuss the direct methods (Gauss-Jordan and Gaussian eliminations) to solve linear systems on distributed memory parallel computers. It will be shown that the so-called row-cyclic storage gives rise to the best performance among the standard three (row-cyclic, column-cyclic and cyclic-cyclic) data storages. We also show that Gauss-Jordan elimination, rather than Gaussian elimination, is highly efficient for the direct solution of linear systems in parallel processing, though Gauss-Jordan elimination requires a larger number of arithmetic operations than Gaussian elimination. Numerical experiment is performed on HITACHI SR12201 with the standard libraries MPI and BLAS.

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신경망을 이용한 차량 객체의 그림자 제거 (Cast-Shadow Elimination of Vehicle Objects Using Backpropagation Neural Network)

  • 정성환;이준환
    • 한국ITS학회 논문지
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    • 제7권1호
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    • pp.32-41
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    • 2008
  • 비디오를 이용한 비전기반 감시에서 움직이는 객체의 추적은 GMM (Gaussian Mixture Model)을 사용한 배경영상과 현재영상의 차이법을 이용한다. 문턱치를 통해 생성된 이진영상을 이용하여 객체 추적을 할 경우 객체 정보가 아닌 그림자에 의하여 객체가 병합되는 현상이 나타난다. 본 논문에서는 신경망(Backpropagation Neural Network)을 이용하여 그림자를 제거하는 방법을 제안하였다. 10개의 동영상에서 객체영역과 캐스트그림자(Cast-Shadow)영역의 훈련용 이미지에서 특징 값을 추출하여 신경망을 훈련시켰다. 캐스트그림자를 제거하는 방법은 이진영상의 객체로 추정되는 영역에서 그림자를 분리하는 방법을 기초로 하며 기존의 그림자 제거 알고리즘 (SNP, SP, DNM1, DNM2, CNCC)보다 그림자 제거 성능이 (16.2%, 38.2%, 28.1%, 22.3%, 44.4%)로 높게 나타났다.

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고응력 분포에 새로운 광탄성실험 하이브릿법 적용 (Application of the Photoelastic Experimental Hybrid Method with New Numerical Method to the High Stress Distribution)

  • 황재석;;이동훈;이동하
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.73-78
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    • 2004
  • In this research, the photoelastic experimental hybrid method with Hook-Jeeves numerical method has been developed: This method is more precise and stable than the photoelastic experimental hybrid method with Newton-Rapson numerical method with Gaussian elimination method. Using the photoelastic experimental hybrid method with Hook-Jeeves numerical method, we can separate stress components from isochromatics only and stress intensity factors and stress concentration factors can be determined. The photoelastic experimental hybrid method with Hook-Jeeves had better be used in the full field experiment than the photoelastic experimental hybrid method with Newton-Rapson with Gaussian elimination method.

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An Algorithm for Computing the Fundamental Matrix of a Markov Chain

  • Park, Jeong-Soo;Gho, Geon
    • 한국경영과학회지
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    • 제22권1호
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    • pp.75-85
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    • 1997
  • A stable algorithm for computing the fundamental matrix (I-Q)$^{-1}$ of a Markov chain is proposed, where Q is a substochastic matrix. The proposed algorithm utilizes the GTH algorithm (Grassmann, Taskar and Heyman, 1985) which is turned out to be stable for finding the steady state distribution of a finite Markov chain. Our algorithm involves no subtractions and therefore loss of significant digits due to concellation is ruled out completely while Gaussian elimination involves subtractions and thus may lead to loss of accuracy due to cancellation. We present numerical evidence to show that our algorithm achieves higher accuracy than the ordinagy Gaussian elimination.

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SATURATION-VALUE TOTAL VARIATION BASED COLOR IMAGE DENOISING UNDER MIXED MULTIPLICATIVE AND GAUSSIAN NOISE

  • JUNG, MIYOUN
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제26권3호
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    • pp.156-184
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    • 2022
  • In this article, we propose a novel variational model for restoring color images corrupted by mixed multiplicative Gamma noise and additive Gaussian noise. The model involves a data-fidelity term that characterizes the mixed noise as an infimal convolution of two noise distributions and the saturation-value total variation (SVTV) regularization. The data-fidelity term facilitates suitable separation of the multiplicative Gamma and Gaussian noise components, promoting simultaneous elimination of the mixed noise. Furthermore, the SVTV regularization enables adequate denoising of homogeneous regions, while maintaining edges and details and diminishing the color artifacts induced by noise. To solve the proposed nonconvex model, we exploit an alternating minimization approach, and then the alternating direction method of multipliers is adopted for solving subproblems. This contributes to an efficient iterative algorithm. The experimental results demonstrate the superior performance of the proposed model compared to other existing or related models, with regard to visual inspection and image quality measurements.

저전력 영상 특징 추출 하드웨어 설계를 위한 공통 부분식 제거 기법 기반 이미지 필터 하드웨어 최적화 (Image Filter Optimization Method based on common sub-expression elimination for Low Power Image Feature Extraction Hardware Design)

  • 김우석;이주성;안호명;김병철
    • 한국정보전자통신기술학회논문지
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    • 제10권2호
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    • pp.192-197
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    • 2017
  • 본 논문은 저전력 영상 특징 추출 하드웨어 설계를 위한 공통 부분식 제거 기법 기반 이미지 필터 하드웨어 최적화 기법을 제안한다. 저전력 및 고성능 물체인식 하드웨어는 공장 자동화를 위한 산업용 로봇에 필수 모듈로 채택되고 있다. 따라서 물체인식 하드웨어의 영상 특징 추출 알고리즘에 다양하게 적용되는 Gaussian gradient 필터 하드웨어의 저면적 설계가 필수적이다. Gaussian gradient 필터의 하드웨어 복잡도를 줄이기 위해 필터에 사용되는 계수의 Symmetric한 특징과 Transposed form FIR 필터 하드웨어 구조를 이용했다. 제안된 이미지 필터의 하드웨어 구조는 알고리즘에 적용된 계수의 변형 없이 구현되었기 때문에 윤곽선 검출 알고리즘에 적용했을 때 검출 데이터의 열화 없이 구현될 수 있다. 제안된 이미지 필터 하드웨어 구조는 기존 구조와 비교했을 때 곱셈기의 수를 50% 절감할 수 있음을 확인했다.

Transmission Matrix Noise Elimination for an Optical Disordered Medium

  • Wang, Lin;Li, Yangyan;Xin, Yu;Wang, Jue;Chen, Yanru
    • Current Optics and Photonics
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    • 제3권6호
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    • pp.496-501
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    • 2019
  • We propose a method to eliminate the noise of a disordered medium optical transmission matrix. Gaussian noise exists whenever light passes through the medium, during the measurement of the transmission matrix and thus cannot be ignored. Experiments and comparison of noise eliminating before and after are performed to illustrate the effectiveness and advance presented by our method. After noise elimination, the results of focusing and imaging are better than the effect before noise elimination, and the measurement of the transmission matrix is more consistent with the theoretical analysis as well.

암호 해독 응용을 위한 공유 메모리 모델상에서의 병렬처리 (Parallel Gaussian elimination on Shared Memory Model with Application to Cryptoanalysis)

  • 정창성;최윤희
    • 정보보호학회지
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    • 제2권2호
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    • pp.47-55
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    • 1992
  • 암호응용분야에 있어서의 이산대수 문제나 인수분해 문제는 방대한 양의 데이타를 다루는 문제로 많은 계산시간이 소요되므로 이들 문제들에 대한 고속 병렬처리는 매우 중요하다. 본 논문에서는 역행렬 문제나 이산대수 문제와 인수분해 문제의 중요한 과정인 선형시스템을 푸는데 효율적인 고속 병렬 알고리즘들을 소개한다.

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Large Solvent and Noise Peak Suppression by Combined SVD-Harr Wavelet Transform

  • Kim, Dae-Sung;Kim, Dai-Gyoung;Lee, Yong-Woo;Won, Ho-Shik
    • Bulletin of the Korean Chemical Society
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    • 제24권7호
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    • pp.971-974
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    • 2003
  • By utilizing singular value decomposition (SVD) and shift averaged Harr wavelet transform (WT) with a set of Daubechies wavelet coefficients (1/2, -1/2), a method that can simultaneously eliminate an unwanted large solvent peak and noise peaks from NMR data has been developed. Noise elimination was accomplished by shift-averaging the time domain NMR data after a large solvent peak was suppressed by SVD. The algorithms took advantage of the WT, giving excellent results for the noise elimination in the Gaussian type NMR spectral lines of NMR data pretreated with SVD, providing superb results in the adjustment of phase and magnitude of the spectrum. SVD and shift averaged Haar wavelet methods were quantitatively evaluated in terms of threshold values and signal to noise (S/N) ratio values.