• 대한의용생체공학회:의공학회지
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• 제25권6호
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• pp.589-598
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• 2004

산모의 흉부와 복부로부터 측정된 다채널 심전도에서 태아 심전도를 추출하는 새로운 알고리듬을 제안한다. 산모의 복부 심전도로부터 태아 심전도를 추출하기 위하여, 시간 영역에서 특이값 분해를 근간으로한 방법이 일반적으로 사용되었다. 그러나 이 방법은 산모와 태아의 심전도 벡터 방향이 서로 직교해야 하는 가정과 많은 연산량을 요구하는 단점이 있다. 제안한 알고리듬은 이산연현변환 영역에서 특이값 분해를 이용하여 이러한 단점을 극복한다. 적은 연산량으로 특이값 분해를 하기 위하여 이산여현변환 계수의 특성과 태아 심전도의 주파수 특성에 기초하여 고주파 수 성분에 해당하는 이산여현변환 계수를 제거하였다. 또한 산모와 태아의 심전도 벡터 방향에 의한 영향을 덜 받으면서 순수한 태아 심전도를 추출하기 위하여, 산모 복부 심전도에서 산모 심전도가 억압된 새로운 세 개의 채널을 만들고 이들을 다채널 심전도에 추가하였다. 모의 신호와 실제 신호를 이용하여 기존의 시간 영역에서 특이값 분해를 근간으로한 방법과 제안한 알고리듬의 성능을 비교하였다. 제안한 알고리듬은 기존 방법보다 적은 연산량으로 순수한 태아 심전도를 얻을 수 있음을 실험적으로 확인되었다.

• 대한전기학회논문지:시스템및제어부문D
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• 제50권6호
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• pp.302-308
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• 2001

SVD(Singular Value Decomposition) filter for the suppression of EMG in multi-lead stress ECG is studied. SVD filter consists of two parts. In the first part, the basis vectors were chosen from the averaged singular vectors obtained from the decomposed noise-free ECG. The singular vector is computed from the stress ECG and is compared itself with basis vectors to know whether the noise exist in stress ECG. In the second part, the existing elimination method is used, when one(or two) channels is(or are) contaminated by noise. But the proposed enhanced SVD filter is used in case of having the noise in the many channels. During signal decomposition and reconstruction, the noise-free channel or the least noisy channel have the weight of 1, the next less noisy channel has the weight of 0.8. In this way, every channel was weighted by decreased of 0.2 in proportion to the amount of the added noise. For the evaluation of the proposed enhanced SVD filter, we compared the SNR computed by the enhanced SVD filter with the standard average filter for the noise-free signal added with artificial noise and the patient data. The proposed SVD filter showed better in the SNR than the standard average filter. In conclusion, we could find that the enhanced SVD filter is more proper in processing multi-lead stress ECG.

• Journal of applied mathematics & informatics
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• 제25권1_2호
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• pp.329-337
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• 2007

In the paper, we obtain the existence of positive solutions and establish a corresponding iterative scheme for BVPs $$\{^{\;(\phi_p(u'))'\;+\;q(t)f(t,u)=0,\;0\;<\;t\;<\;1,}_{\;u(0)\;-\;B(u'({\eta}))\;=\;0,\;u'(1)\;=\;0}$$ and $$\{^{\;(\phi_p(u'))'\;+\;q(t)f(t,u)=0,\;0\;<\;t\;<\;1,}_{\;u'(0)\;=\;0,\;u(1)+B(u'(\eta))\;=\;0.}$$. The main tool is the monotone iterative technique. Here, the coefficient q(t) may be singular at t = 0, 1.

• Journal of information and communication convergence engineering
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• 제4권4호
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• pp.136-140
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• 2006

In this paper, we consider the detection of orthogonal space-time block codes (OSTBCs) without channel state information (CSI) at the receiver. Based on the conventional blind cyclic decoder, we propose an enhanced blind cyclic decoder which has higher system performance than the conventional one. Furthermore, the proposed decoder offers low complexity since it does not require the computation of singular value decomposition.

• 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.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2654-2659
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• 2003

In this paper, we present biomimetic hopping strategy which is more human-like for legged robot through stiffness modulation. Stiffness value is calculated from the motion of body center of gravity. This method enable to reduce impact force on touch-down, adaption on ground stiffness change and height modulation. Simple selected models will be used to validate this method. For general model, singular perturbation is used for control and simulation using stiffness modulation is presented.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(3)
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• pp.47-50
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• 2001

This paper took advantage of SVD (Singular value Decomposition) techniques of LSI(Latent Semantic Indexing) to grasp easily terminology distribution. Existent LSI did to static database, propose that apply to dynamic database in this paper. But, if dynamic applies LSI to database, updating problem happens. Existent updating way is Recomputing method, Folding-in method, SVD-updating method. Proposed QR decomposition method to show performance improvement than existent three methods in this paper.

• Journal of applied mathematics & informatics
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• 제10권1_2호
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• pp.101-109
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• 2002

We extend two inequalities involving Hadamard Products of Positive definite Hermitian matrices to positive semi-definite Hermitian matrices. Simultaneously, we also show the sufficient conditions for equalities to hold. Moreover, some other matrix inequalities are also obtained. Our results and methods we different from those which are obtained by S. Liu in [J. Math. Anal. Appl. 243:458-463(2000)] and B.-Y Wang et al in [Lin. Alg. Appl. 302-303: 163-172(1999)] .

• Communications for Statistical Applications and Methods
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• 제12권3호
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• pp.705-712
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• 2005

Biplot is a graphical display of the rows and columns of an n${\times}$p data matrix. In particular, Gabriel (1995) suggested the MANOVA biplot using singular value decomposition (SVD) with the averages of response variables according to treatment groups. But his biplot may cause wrong results by disregarding them when there exist covariate effects. In this paper, we will provide the MANCOA biplot based on the SVD with the parameter estimates for MANCOVA model when there exist covariate effects.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 A
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• pp.135-138
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• 2003

In this paper, we provide a reliable few controller design method for descriptor systems satisfying asymptotic stability with $H_\infty$ norm bound and all actuator failures occurred within the pre-specified subset. The proper condition for the existence of a reliable $H_\infty$ controller and the controller design method are proposed by linear matrix inequality(LMI), Schur complements, and singular value decomposition. All solutions can be obtained simultaneously because the presented sufficient condition can be expressed as an LMI form.