• Title/Summary/Keyword: SVD(singular value decomposition)

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Application of SVD on Suppression of IEEE 802.11a Interference in TH-PAM UWB Systems

  • Xu, Shaoyi;Bai, Zhiquan;Yang, Qinghai;Kwak, Kyung-Sup
    • ETRI Journal
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    • v.29 no.2
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    • pp.237-239
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    • 2007
  • Interference from IEEE 802.11a systems affects ultra-wideband (UWB) systems significantly. In this letter, we suggest a novel narrow-band interference (NBI) suppression technique based on the singular value decomposition (SVD) algorithm in time-hopping pulse amplitude modulation (TH-PAM) UWB systems. The SVD algorithm is used to approximate the interference which then is subtracted from the received signals. In contrast to the conventional notch filter and rake receiver, our method is more effective and the receiver complexity can be greatly reduced.

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On-line Monitoring Using SVD in a Electron Beam Welding (전자빔 용접에서 SVD을 이용한 온라인 모니터링)

    • Journal of Welding and Joining
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    • v.18 no.1
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    • pp.97-103
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    • 2000
  • Time series analysis results show the SVD is a candidate of on-line monitoring of welding penetration when the covariance matrix of a full penetration is used as a mapping function. As the reconstructed embedding vectors from the chaotic scalar time series are manipulated by the covariance matrix, the mapped tim series lie on a hyper-ellipsoid which the lengths of semi-axes are the squared eigenvalues of the covariance matrix in the case of full penetration. These visualize by two dimensional stroboscope views. The other cases like partial penetration, are different in the sense of sizes and shapes. Here we test two types of time series; the ion current and the X-ray. The ion current is better than the X-ray as an on-line monitoring signal, because the difference of the eigenvalue spectrum of the ion(between the pull penetration and partial penetration) is bigger than those of the X-ray.

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Texture Image Retrieval Using DTCWT-SVD and Local Binary Pattern Features

  • Jiang, Dayou;Kim, Jongweon
    • Journal of Information Processing Systems
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    • v.13 no.6
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    • pp.1628-1639
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    • 2017
  • The combination texture feature extraction approach for texture image retrieval is proposed in this paper. Two kinds of low level texture features were combined in the approach. One of them was extracted from singular value decomposition (SVD) based dual-tree complex wavelet transform (DTCWT) coefficients, and the other one was extracted from multi-scale local binary patterns (LBPs). The fusion features of SVD based multi-directional wavelet features and multi-scale LBP features have short dimensions of feature vector. The comparing experiments are conducted on Brodatz and Vistex datasets. According to the experimental results, the proposed method has a relatively better performance in aspect of retrieval accuracy and time complexity upon the existing methods.

A New Algorithm for Extracting Fetal ECG from Multi-Channel ECG using Singular Value Decomposition in a Discrete Cosine Transform Domain (산모의 다채널 심전도 신호로부터 이산여현변환영역에서 특이값 분해를 이용한 태아 심전도 분리 알고리듬)

  • Song In-Ho;Lee Sang-Min;Kim In-Young;Lee Doo-Soo;Kim Sun I.
    • Journal of Biomedical Engineering Research
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    • v.25 no.6
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    • pp.589-598
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    • 2004
  • We propose a new algorithm to extract the fetal electrocardiogram (FECG) from a multi-channel electrocardiogram (ECG) recorded at the chest and abdomen of a pregnant woman. To extract the FECG from the composite abdominal ECG, the classical time-domain method based on singular value decomposition (SVD) has been generally used. However, this method has some disadvantages, such as its high degree of computational complexity and the necessary assumption that vectors between the FECG and the maternal electrocardiogram (MECG) should be orthogonal. The proposed algorithm, which uses SVD in a discrete cosine transform (DCT) domain, compensates for these disadvantages. To perform SVD with lower computational complexity, DCT coefficients corresponding to high-frequency components were eliminated on the basis of the properties of the DCT coefficients and the frequency characteristics of the FECG. Moreover, to extract the pure FECG with little influence of the direction of the vectors between the FECG and MECG, three new channels were made out of the MECG suppressed in the composite abdominal ECG, and the new channels were appended to the original multi-channel ECG. The performance of the proposed algorithm and the classical time-domain method based on SVD were compared using simulated and real data. It was experimentally verified that the proposed algorithm can extract the pure FECG with reduced computational complexity.

An Identification Technique Based on Adaptive Radial Basis Function Network for an Electronic Odor Sensing System

  • Byun, Hyung-Gi
    • Journal of Sensor Science and Technology
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    • v.20 no.3
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    • pp.151-155
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    • 2011
  • A variety of pattern recognition algorithms including neural networks may be applicable to the identification of odors. In this paper, an identification technique for an electronic odor sensing system applicable to wound state monitoring is presented. The performance of the radial basis function(RBF) network is highly dependent on the choice of centers and widths in basis function. For the fine tuning of centers and widths, those parameters are initialized by an ill-conditioned genetic fuzzy c-means algorithm, and the distribution of input patterns in the very first stage, the stochastic gradient(SG), is adapted. The adaptive RBF network with singular value decomposition(SVD), which provides additional adaptation capabilities to the RBF network, is used to process data from array-based gas sensors for early detection of wound infection in burn patients. The primary results indicate that infected patients can be distinguished from uninfected patients.

3-Dimensional Dental Surgery System based on PC using anatomical landmarks (해부학적 계측점을 이용한 PC-기반3차원 치과수술 시스템)

  • 이경상;유선국;김형돈;배현수;김남현
    • Journal of Biomedical Engineering Research
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    • v.20 no.2
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    • pp.139-148
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    • 1999
  • In this paper, we designed the dental surgery system based on PC. This system predict post operated 3-dimensional image, So the patient has no need to take CT after surgery and expose his body to radiological damage. We predict the post operated skull from the patient's CT with pre and post cephalometry X-ray. Our novel procedures, to register X-ray and CT, are based on anatomical landmarks, singular value decomposition. And we display the predicted image 3-dimensionally by surface rendering. We verified this system by dry skull experiment and clinical experiment. When significance level is 0.05, there is on significance.

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An Effective Selection of white Gaussian Noise Sub-band using Singular Value Decomposition (특이값 분해를 이용한 효율적인 백색가우시안 잡음대역 선정 방법)

  • Shin, Seung-Min;Kim, Young-Soo;Kim, Sang-Tae;Suk, Mi-Kyung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.3A
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    • pp.272-280
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    • 2009
  • Measurement of the background radio noise is very important process being used in survey of radio noise environment, calculating the threshold level for the frequency occupancy measurement and so forth. First step of background radio noise measurement is to select the sample sub-band which is mostly dominated by the background white Gaussian noise (WGN) within the target band. The second step is to carry out the main measurement of radio noise on this selected sample sub-band for the representative value of the noise power. In this paper, a method for selection of sample sub-band for the effective background radio noise measurement using SVD is proposed under the assumption that background radio noise is WGN. The performance of the proposed method is compared with that of the APD method which is widely used for the same purpose. Simulation results are shown to demonstrate the high performance of the proposed method in comparison with the existing APD method.

3D Model Construction from Image Scanning without Iteration or SVD (2차원 영상 템플릿으로부터 3차원 모델 템플릿 형성 - SVD가 필요 없는 선형 방법)

  • Han, Youngmo
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.11
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    • pp.165-170
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    • 2013
  • When we build up a 3D model from the given 2D images, linear algorithms are often used to reduce computational cost or for initialization of nonlinear algorithms. However, contemporary linear algorithms have apparently linear structures, but virtually they are implemented using SVD. The SVD is also implemented using numerical analysis algorithms that need initialization. Moreover, solutions using SVD are more difficult to analyze than closed-form solutions. To avoid from such inconvenient numerical analysis algorithms of the contemporary methods and for convenient analysis of solutions, this paper proposes a convenient linear method that produces a closed-form solution.

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.

Digital Watermarking Method for User's Certification of Camera-Phone (카메라 폰 상에서 사용자 인증을 위한 디지털 워터마킹 기법)

  • Lee, Seung-Ik;Sohn, Jae-Sik;Im, Sung-Woon;Kim, Duk-Gyoo
    • Journal of Korea Society of Industrial Information Systems
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    • v.13 no.3
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    • pp.1-8
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    • 2008
  • In the event of a traffic accident, a fire accident, or a criminal act, anyone will be able to capture these important moments and use authentic photographs for evidence purposes. Digital watermarking is able to ensure that the digital photographs taken from a particular camera-phone are authentic and indeed. This paper presents a blind image watermarking technique for digital phone camera. This method is based on singular value decomposition (SVD) and wavelet decomposition. Experimental results show that the proposed technique performs well in security and robustness against JPEG compression.

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