• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 춘계학술대회논문집; 경주코오롱호텔; 22-23 May 1997
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• pp.102-109
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• 1997

A study to determine a proper sensor placement was developed to improve force identification. Improper selection of response position cause erroneous result in force identification problem. This paper presents two methods to improve the conditioning of the system's FRM(Frequency Response Matrix) which affects the accuracy of result. The basic strategy of the two methods in selecting the response position is to let the smallest singular value be as large as possible by maximizing the orthogonality of FRM. The suggested methods are tested numerically with a fixed-fixed beam model. The test results show that the proposed methods are very effective in dealing with the force identification problem.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권7호
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• pp.2879-2890
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• 2020

In this paper, we study the estimation of angle, range and polarization parameters of a bistatic polarization sensitive frequency diverse array multiple-input multiple-output (PSFDA-MIMO) radar system. The application of polarization sensitive array in receiver is explored. A signal model of bistatic PSFDA-MIMO radar system is established. In order to utilize the multi-dimensional structure of array signals, the matched filtering radar data can be represented by a third-order tensor model. A joint estimation of the direction-of-departure (DOD), direction-of-arrival (DOA), range and polarization parameters based on parallel factor (PARAFAC) algorithm is proposed. The proposed algorithm does not need to search spectral peaks and singular value decomposition, and can obtain automatic pairing estimation. The method was compared with the existing methods, and the results show that the performance of the method is better. Therefore, the accuracy of the parameter estimation is further improved.

• 대기
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• 제18권2호
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• pp.83-95
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• 2008

In this study we have investigated the preceding eighteen large-scale climate indices with a lead time from zero to twelve months that have an influence on the variability of temperature and precipitation in Korea in order to understand which climate indices are overall available as predictors for long-range forecasting. We also have studied the dynamic link between preceding large-scale climate indices and regional climate using singular value decomposition analysis (SVDA) and correlation analysis (CA). Based on the coupled mode between large-scale circulation and regional climate, and correlation pattern between the preceding large-scale climate indices and large-scale circulation, the level of significance on climate indices as a predictor for monthly mean temperature and precipitation was evaluated for 5 and 1% level.

• Structural Engineering and Mechanics
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• 제21권3호
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• pp.237-254
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• 2005

This article deals with the reconstruction of an impact force. This requires to take measurements from the impacted structures and then to deconvolve those signals from the impulse response function. More precisely, the purpose of the work described here is to analyse the method of deconvolution and the problems that it implies. Thus, it is highlighted that the associated deconvolution problem depends on the location of the measurement points: it is possible or not to reconstruct the force of impact in function of the location of this point. Then, the role of the antiresonances is linked up with this problem. The singular value decomposition is used to understand these difficulties. Numerical predictions are compared and validated with experiments.

• Geomechanics and Engineering
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• 제9권2호
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• pp.207-218
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• 2015

In this paper, forming of fully clamped circular plate by using low velocity impact system has been investigated. This system consists of liquid shock tube and gravity drop hammer. A series of test on mild steel and aluminum alloy plates has been done. The effect of varying both impact load and the plate material on the deflection are described. This paper also presents a simple model to prediction of mid-point deflection of circular plate by using input-output experimental data. In this way, singular value decomposition (SVD) method is used in conjunction with dimensionless number incorporated in such complex process. The results of obtained model have very good agreement with experimental data and it provides a way of studying and understanding the plastic deformation of impact loads.

• 한국기계연구소 소보
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• 통권19호
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• pp.81-92
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• 1989

This paper presents a simple identification method of the actual kinematic parameters for the robot with parallel joints. It is known that Denavit-Hartenberg's coordinate system is not useful for nearly parallel joints. In this paper, the coordinate frames are reassigned to model the kinematic parameter between nearly parallel joints by four parameters. The proposed identification method uses a straight ruler about 1m long. A robot hand is placed by using a teaching pendant at the prescribed points on the ruler, and corresponding error function is defined. The identified kinematic parameters which make the error function zero are obtained by iterative least square error method based on the singular value decomposition. In the compensation of joint angles, only the position is considered because the usual applications of robot do not require a precise orientation control.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.53-54
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• 2007

이 논문에서는 구동기 용량제한을 갖는 선형시스템에 대한 저이득 추종 제어기 설계 문제를 다룬다. 주어진 시스템에 대한 추종 기준입력은 크기와 변화율에 제한을 갖는 시간에 따라 변화하는 일반적인 입력을 고려하며 제어기 설계 과정은 추종성능을 향상시키기 위한 2단계의 시스템 등가변환으로 구성된다. 먼저 제1단계에서는 잘 알려진 SVD(Singular Value Decomposition)의 원리를 활용하여 추종출력과 관련된 상태를 효율적으로 분리한 후 추종에러를 상태방정식 내에 포함하는 제2단계의 시스템 변환을 통하여 추종성능의 향상을 꾀한다. 제안된 추종 제어기의 설계 조건은 모두 LMI 형태로 표현 가능하며 잘 알려진 수치예제를 통하여 제안된 설계 기법의 효용성을 예시한다.

• Steel and Composite Structures
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• 제7권5호
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• pp.355-376
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• 2007

The purpose of this study is to predict and investigate the time-dependent creep behavior of composite materials. For this, firstly the evaluation method for the modulus of elasticity of whole fiber and matrix is presented from the limited information on fiber volume fraction using the singular value decomposition method. Then, the effects of fiber volume fraction on modulus of elasticity of GFRP are verified. Also, as a creep model, the nonlinear curve fitting method based on the Marquardt algorithm is proposed. Using the existing Findley's power creep model and the proposed creep model, the effect of fiber volume fraction on the nonlinear creep behavior of composite materials is verified. Then, for the time-dependent analysis of a composite material subjected to uniaxial tension and simple shear loadings, a user-provided subroutine UMAT is developed to run within ABAQUS. Finally, the creep behavior of center loaded beam structure is investigated using the Hermitian beam elements with shear deformation effect and with time-dependent elastic and shear moduli.

• 제어로봇시스템학회논문지
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• 제3권6호
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• pp.582-587
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• 1997

This paper deals with the control problem under nonlinear boiler systems with noise, and input constraints. MCMBPC(Multivariable Constrained Model-Based Predictive Controller) proposed by Wilkinson et al.[10,11] is used and nominal model is modified in this paper in order to applied to nonlinear boiler systems with feed-forward terms. The solution of the cost function optimization constrained on input and/or output variables is achieved using quadratic programming, via singular value decomposition(SVD). The controller designed is shown to satisfy the constraints and to have excellent tracking performance via simulation applied to nonlinear dynamic drum boiler turbine model for 16OMW unit.

• 대한전자공학회논문지SP
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• 제46권5호
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• pp.15-24
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• 2009

Compressed sensing은 소수의 선형 관측으로부터 sparse 신호를 복원하는 문제를 언급하고 있다. 최근 벡터 경우에서의 성공적인 연구 결과가 행렬의 경우로 확장되었다. Low-rank 행렬의 compressed sensing은 ill-posed inverse problem을 low-rank 정보를 이용하여 해결한다. 본 문제는 rank 최소화 혹은 low-rank 근사의 형태로 나타내질 수 있다. 본 논문에서는 최근 제안된 여러 가지 효율적인 알고리즘에 대한 survey를 제공한다.