• Title/Summary/Keyword: a SVD decomposition

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Improvement of Computational Speed for the SVD Background Clutter Signal Subtraction Algorithm in IR-UWB Radar Systems (IR-UWB Radar 시스템에서 특이값 분해를 이용한 클러터 신호 제거 알고리즘의 연산속도 향상 기법)

  • Baek, In Seok;Jung, Moon Kwun;Cho, Sung Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.1
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    • pp.89-96
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    • 2013
  • This paper presents an improved clutter signal removal algorithm using Singular Value Decomposition(SVD). For indoor positioning system using IR-UWB Radar, the target signal is extracted from received signal. We use clutter signal removal algorithm using SVD for target signal extraction. Clutter signal removal algorithm using SVD has the advantage of operation but the disadvantage of high computational complexity. In this paper, we propose a method to improve computational complexity. As the experimental results, it is confirmed that the method presented in this paper improve the computational complexity of clutter removal algorithm using SVD.

Digital Image Watermarking Scheme in the Singular Vector Domain (특이 벡터 영역에서 디지털 영상 워터마킹 방법)

  • Lee, Juck Sik
    • Journal of the Institute of Convergence Signal Processing
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    • v.16 no.4
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    • pp.122-128
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    • 2015
  • As multimedia information is spread over cyber networks, problems such as protection of legal rights and original proof of an information owner raise recently. Various image transformations of DCT, DFT and DWT have been used to embed a watermark as a token of ownership. Recently, SVD being used in the field of numerical analysis is additionally applied to the watermarking methods. A watermarking method is proposed in this paper using Gabor cosine and sine transform as well as SVD for embedding and extraction of watermarks for digital images. After delivering attacks such as noise addition, space transformation, filtering and compression on watermarked images, watermark extraction algorithm is performed using the proposed GCST-SVD method. Normalized correlation values are calculated to measure the similarity between embedded watermark and extracted one as the index of watermark performance. Also visual inspection for the extracted watermark images has been done. Watermark images are inserted into the lowest vertical ac frequency band. From the experimental results, the proposed watermarking method using the singular vectors of SVD shows large correlation values of 0.9 or more and visual features of an embedded watermark for various attacks.

ANALYSIS OF EIGEN VALUES FOR EFFECTIVE CHOICE OF SNAPSHOT DATA IN PROPER ORTHOGONAL DECOMPOSITION (적합직교분해 기법에서의 효율적인 스냅샷 선정을 위한 고유값 분석)

  • Kang, H.M.;Jun, S.O.;Yee, K.
    • Journal of computational fluids engineering
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    • v.22 no.1
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    • pp.59-66
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    • 2017
  • The guideline of selecting the number of snapshot dataset, $N_s$ in proper orthogonal decomposition(POD) was presented via the analysis of Eigen values based on the singular value decomposition(SVD). In POD, snapshot datasets from the solutions of Euler or Navier-Stokes equations are utilized to SVD and a reduced order model(ROM) is constructed as the combination of Eigen vectors. The ROM is subsequently applied to reconstruct the flowfield data with new set of flow conditions, thereby enhancing the computational efficiency. The overall computational efficiency and accuracy of POD is dependent on the number of snapshot dataset; however, there is no reliable guideline of determining $N_s$. In order to resolve this problem, the order of maximum to minimum Eigen value ratio, O(R) from SVD was analyzed and presented for the decision of $N_s$; in case of steady flow, $N_s$ should be determined to make O(R) be $10^9$. For unsteady flow, $N_s$ should be increased to make O(R) be $10^{11\sim12}$. This strategy of selecting the snapshot dataset was applied to two dimensional NACA0012 airfoil and vortex flow problems including steady and unsteady cases and the numerical accuracies according to $N_s$ and O(R) were discussed.

Mode-SVD-Based Maximum Likelihood Source Localization Using Subspace Approach

  • Park, Chee-Hyun;Hong, Kwang-Seok
    • ETRI Journal
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    • v.34 no.5
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    • pp.684-689
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    • 2012
  • A mode-singular-value-decomposition (SVD) maximum likelihood (ML) estimation procedure is proposed for the source localization problem under an additive measurement error model. In a practical situation, the noise variance is usually unknown. In this paper, we propose an algorithm that does not require the noise covariance matrix as a priori knowledge. In the proposed method, the weight is derived by the inverse of the noise magnitude square in the ML criterion. The performance of the proposed method outperforms that of the existing methods and approximates the Taylor-series ML and Cram$\acute{e}$r-Rao lower bound.

Fault Detection and Isolation using Singular Value Decomposition for Redundant Sensors System (특이치 분해를 이용한 중복 센서의 EDI 기법과 성능 분석)

  • 심덕선;양철관
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.4
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    • pp.364-370
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    • 2004
  • In this paper, we propose a FDI method, which comes from singular value decomposition of measurement matrix fur redundant sensors. We analyze the performance of the proposed FDI method by comparing with the GLT method in two ways such as FDI performance and GN&C performance. Also, we propose a GN&C performance index by combining FDI and GN&C performance.

Text Summarization using PCA and SVD (주성분 분석과 비정칙치 분해를 이용한 문서 요약)

  • Lee, Chang-Beom;Kim, Min-Soo;Baek, Jang-Sun;Park, Hyuk-Ro
    • The KIPS Transactions:PartB
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    • v.10B no.7
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    • pp.725-734
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    • 2003
  • In this paper, we propose the text summarization method using PCA (Principal Component Analysis) and SVD (Singular Value Decomposition). The proposed method presents a summary by extracting significant sentences based on the distances between thematic words and sentences. To extract thematic words, we use both word frequency and co-occurence information that result from performing PCA. To extract significant sentences, we exploit Euclidean distances between thematic word vectors and sentence vectors that result from carrying out SVD. Experimental results using newspaper articles show that the proposed method is superior to the method using either word frequency or only PCA.

A New Method for Robust and Secure Image Hash Improved FJLT

  • Xiu, Anna;Kim, Hyoung-Joong
    • 한국정보통신설비학회:학술대회논문집
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    • 2009.08a
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    • pp.143-146
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    • 2009
  • There are some image hash methods, in the paper four image hash methods have been compared: FJLT (Fast Johnson- Lindenstrauss Transform), SVD (Singular Value Decomposition), NMF (Non-Negative Matrix Factorization), FP (Feature Point). From the compared result, FJLT method can't be used in the online. the search time is very slow because of the KNN algorithm. So FJLT method has been improved in the paper.

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A Coupled Recursive Total Least Squares-Based Online Parameter Estimation for PMSM

  • Wang, Yangding;Xu, Shen;Huang, Hai;Guo, Yiping;Jin, Hai
    • Journal of Electrical Engineering and Technology
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    • v.13 no.6
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    • pp.2344-2353
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    • 2018
  • A coupled recursive total least squares (CRTLS) algorithm is proposed for parameter estimation of permanent magnet synchronous machines (PMSMs). TLS considers the errors of both input variables and output ones, and thus achieves more accurate estimates than standard least squares method does. The proposed algorithm consists of two recursive total least squares (RTLS) algorithms for the d-axis subsystem and q-axis subsystem respectively. The incremental singular value decomposition (SVD) for the RTLS obtained by an approximate calculation with less computation. The performance of the CRTLS is demonstrated by simulation and experimental results.

A study on convergence and stabilization of SVD damped least squares method in the triplet camera lens-system design (카메라 렌즈 설계에서 직교화 방법에 관한 연구)

  • Jung, Jung Bok;Lee, Won Gin;Kim, Kyung Chan
    • Journal of Korean Ophthalmic Optics Society
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    • v.1 no.1
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    • pp.29-39
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    • 1996
  • We studied the method which would determine the appropriate additive damping factor for the damped least sequres(DLS) optimization. We calculated eigenvalues of the product of the Jacobian matrix of error function by using the singular value decomposition(SVD) method. While suitable damping factor was appiled to the additive DLS by using SVD and Gaussian elimination method, the convergence and stability of the optimization process were examined in a triplet-type camera lens-system where the condition number is well conditioned. We compared the convergence and stability of merit function when median, maximum and minimum of eigenvalues were used as a damping factor in the optimization process. When damping factor is median of eigenvalue, the convergence and stability of merit function are more excellent than in the case of two other eigenvalues. Thus, we adopt the median of eigenvalues as an appropriate damping factor. Next, by using SVD and Gaussian elimination method, we compound the convergence and stability of optimization process for triplet-type camera lens-system design. In these two method; triplet-type camera lens-system in which condition number is well conditioned, has little improvement with the combination of DLS and SVD.

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A Space Division Multiple Access Technique for Downlink MIMO Systems (하향링크 MIMO 시스템을 위한 공간분할 다중접속 기술)

  • Rim, Min-Joong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.9A
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    • pp.1022-1030
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    • 2004
  • The next generation cellular radio systems require high data rate transmission and large system capacity In order to meet these requirements, multiple antennas can be used at the base and mobile stations, forming MIMO(multiple-input, multiple-output) channels This paper considers a downlink MIMO system assuming a large number of base station antennas, a small number of mobile station antennas, and rich-scattering, quasi-stationary, and flat-fading channel environments When the channel state information is given at the base station in a single user system, a MIMO technique with SVD(singular value decomposition) and water-filling can achieve the maximal downlink channel capacity. In multi-user environments, however, SDMA(space division multiple acces) technique can be used to further increase the total channel capacity supported by the base station This paper proposes a MIMO SDMA technique which can transmit parallel data streams to each of multiple users. The proposed method. can achieve higher total channel capacity than SVD-based MIMO techniques or conventional SDMA using smart antennas.