• 지질공학
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• 제28권3호
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• pp.465-473
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• 2018

육상 탄성파자료에 나타나는 일관성 잡음인 그라운드롤을 제거하기 위해 특이값 분해 필터링의 적용성을 살펴보았다. 상관성이 높은 반사에너지가 요구되는 특이값의 계산을 위해 먼저 자동이득제어로 감쇠된 진폭을 보상하고 송수신점의 높이보정 및 풍화대 보정을 실시하여 장파장 시간차이를 제거한 후, 나머지 정적보정으로 단파장 시간차이를 완화시켜 반사면의 수평적인 연속성을 높였다. 특이값 분해 필터링에 적합한 입력인자(최대 주성분)는 공통중간점 자료에 수직시간차 역보정을 수행하여 얻은 공통발파점 자료에 대한 연속 테스트로 결정하였다. 그라운드롤의 시간에 따른 분산이 뚜렷한 현장자료에서 특이값 분해 필터링은 일반적인 기법인 f-k 필터링에 비해 반사신호의 왜곡없이 그라운드롤의 영향을 최소화하면서 주요 반사면들의 연속성을 향상시키는데, 이것은 진폭 빛띠에서 반사파의 낮은 진동수 성분들이 필터링 후에도 보존되었다는 점과 잘 상관되었다. 특히 특이값 분해 필터링을 거친 후 S/N 비를 높일 수 있는 자료처리(송곳곱풀기, 시간변화 빛띠흰색화) 과정을 함께 수행하여 겹쌓기한 결과 저류층을 포함한 주요 반사면들의 향상된 연속성과 분해능을 확인할 수 있었다.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2015년도 추계학술대회
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• pp.173-175
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• 2015

We proposed a blind watermarking scheme using singular vectors based on Discrete Wavelet Transform (DWT) and Redundant Discrete Wavelet Transform (RDWT) combined with Singular Value Decomposition (SVD) for copyright protection application. We replaced the 1st left and right singular vectors decomposed from cover image with the corresponding ones from watermark image to overcome the false-positive problem in current watermark systems using SVD. The proposed scheme realizes the watermarking system without a false positive problem, and shows high fidelity and robustness.

• 한국항해항만학회지
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• 제38권2호
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• pp.89-96
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• 2014

This paper presents an improvement for calculating method of astronomical ship position based on circle of equal altitude equation. In addition, to enhance the accuracy of ship position achieved from solving equation system, the authors used singular value decomposition (SVD) in least square method instead of normal decomposition. In maths, the SVD was proved more numerically stable than normal decomposition. Therefore, the solution of equation system will be more efficient and the result would be more accurate than previous methods. By proposal algorithm, a computer program have been developed to help the navigators in calculating directly ship position when the modern equipment has failure. Finally, some of experiments are carried out to verify effectiveness of proposed algorithm, the results show that the accuracy of ship position based on new method is better than the intercept method.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.133-138
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• 2006

Singular value decomposition (SDV) approach is applied to the observability analysis of GPS/INS in this paper. A measure of observability for a subspace is introduced. It indicates the minimum size of perturbation in the information matrix that makes the subspace unobservable. It is shown that the measure has direct connections with observability of systems, error covariance, and singular structure of the information matrix. The observability measure given in this paper is applicable to the multi-input/multi-output time-varying systems. An example on the observability analysis of GPS/INS is given. The measure of observability is confirmed to be less sensitive to system model perturbation. It is also shown that the estimation error for the vertical component of gyro bias can be considered unobservable for small initial error covariance for a constant velocity horizontal motion.

• 한국정보통신학회논문지
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• 제11권5호
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• pp.997-1003
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• 2007

이 논문에서는 LCD에 사용되는 편광필름 영상에서 결함을 검출하는 방법을 제안하였다. 제안한 방법은 결함의 지엽적인 특징을 이용하는 것이 아니라 특이값 분해를 이용하여 영상의 전역적인 정보를 반영하는 방법이다. 편광필름 영상을 특이값 분해하고 특이값 중에서 첫 번째 특이값만을 사용하여 영상을 재구성하면 재구성한 영상에서 정상 부분의 화소값과 결함 부분의 화소값들은 서로 다른 특성을 나타낸다. 입력 영상과 재구성한 영상의 화소값 비를 구하고 확률론적 방법을 사용하여 결함을 검출하였다. 제안한 방법을 이용하여 여러 가지 결함을 갖는 편광필름 영상에서 결함을 검출한 결과 검출력이 매우 우수한 것으로 나타났다.

• 유통과학연구
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• 제14권9호
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• pp.25-29
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• 2016

Purpose - Finding top K persuaders in consumer network is an important problem in marketing. Recently, a new method of computing persuasion scores, interpreted as fixed point or stable distribution for given persuasion probabilities, was proposed. Top K persuaders are chosen according to the computed scores. This research proposed a new definition of persuasion scores relaxing some conditions on the matrix of probabilities, and a method to identify top K persuaders based on the defined scores. Research design, data, and methodology - A new method of computing top K persuaders is computed by singular value decomposition (SVD) of the matrix which represents persuasion probabilities between entities. Results - By testing a randomly generated instance, it turns out that the proposed method is essentially different from the previous study sharing a similar idea. Conclusions - The proposed method is shown to be valid with respect to both theoretical analysis and empirical test. However, this method is limited to the category of persuasion scores relying on the matrix-form of persuasion probabilities. In addition, the strength of the method should be evaluated via additional experiments, e.g., using real instances, different benchmark methods, efficient numerical methods for SVD, and other decomposition methods such as NMF.

• Journal of Communications and Networks
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• 제17권5호
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• pp.491-498
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• 2015

Recognition of radar emitter signals is one of core elements in radar reconnaissance systems. A novel method based on singular value decomposition (SVD) and the main ridge slice of ambiguity function (AF) is presented for attaining a higher correct recognition rate of radar emitter signals in case of low signal-to-noise ratio. This method calculates the AF of the sorted signal and ascertains the main ridge slice envelope. To improve the recognition performance, SVD is employed to eliminate the influence of noise on the main ridge slice envelope. The rotation angle and symmetric Holder coefficients of the main ridge slice envelope are extracted as the elements of the feature vector. And kernel fuzzy c-means clustering is adopted to analyze the feature vector and classify different types of radar signals. Simulation results indicate that the feature vector extracted by the proposed method has satisfactory aggregation within class, separability between classes, and stability. Compared to existing methods, the proposed feature recognition method can achieve a higher correct recognition rate.

• Journal of Electrical Engineering and Technology
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• 제13권6호
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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.

• ETRI Journal
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• 제34권5호
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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.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.313-316
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• 1997

Two different issues, design of reduced-order robust model predictive control and input signal design for identification of a MIMO system, are addressed and design techniques based on singular value decomposition(SVD) of the pulse response circulant matrix(PRCM) are proposed. For this, we investigate the properties of the PRCM, which is a periodic approximation of a linear discrete-time system, and show its SVD represents the directional as well as the frequency decomposition of the system. Usefulness of the PRCM and effectiveness of the proposed design techniques are demonstrated through numerical examples.