• Title/Summary/Keyword: gauss-newton

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Linear and Nonlinear Analysis of Initially Stressed Elastic Solid (초기응력이 있는 탄성체의 선형 및 비선형해석 -플레이트 스트립을 중심으로)

  • 권영두;최진민
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.12 no.4
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    • pp.642-651
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    • 1988
  • The present paper develops finite element procedures to calculate displacements, strains and stresses in initially stressed elastic solids subjected to static or time-dependent loading conditions. As a point of departure, we employ Hamilton's principle to obtain nonlinear equations of motion characterizing the displacement in a solid. The equations of motion reduce to linear equations of motion if incremental stresses are assumed to be infinitesimal. In the case of linear problem, finite element solutions are obtained by Newmark's direct integration method and by modal analysis. An analytic solution is referred to compare with the linear finite element solution. In the case of nonlinear problem, finite element solutions are obtained by Newton-Raphson iteration method and compared with the linear solution. Finally, the effect of the order of Gauss-Legendre numerical integration on the nonlinear finite element solution, has been investigated.

Unit Root Test for Temporally Aggregated Autoregressive Process

  • Shin, Dong-Wan;Kim, Sung-Chul
    • Journal of the Korean Statistical Society
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    • v.22 no.2
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    • pp.271-282
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    • 1993
  • Unit root test for temporally aggregated first order autoregressive process is considered. The temporal aggregate of fist order autoregression is an autoregressive moving average of order (1,1) with moving average parameter being function of the autoregressive parameter. One-step Gauss-Newton estimators are proposed and are shown to have the same limiting distribution as the ordinary least squares estimator for unit root when complete observations are available. A Monte-Carlo simulation shows that the temporal aggregation have no effect on the size. The power of the suggested test are nearly the same as the powers of the test based on complete observations.

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A Study on the SPICE Model Parameter Extraction Method for the DC Model of the High Voltage MOSFET (High Voltage MOSFET의 DC 해석 용 SPICE 모델 파라미터 추출 방법에 관한 연구)

  • Lee, Un-Gu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.12
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    • pp.2281-2285
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    • 2011
  • An algorithm for extracting SPICE MOS level 2 model parameters for the high voltage MOSFET DC model is proposed. The optimization method for analyzing the nonlinear data of the current-voltage curve using the Gauss-Newton algorithm is proposed and the pre-process step for calculating the threshold voltage and the mobility is proposed. The drain current obtained from the proposed method shows the maximum relative error of 5.6% compared with the drain current of 2-dimensional device simulation for the high voltage MOSFET.

LEAST-SQUARES METHOD FOR THE BUBBLE STABILIZATION BY THE GAUSS-NEWTON METHOD

  • Kim, Seung Soo;Lee, Yong Hun;Oh, Eun Jung
    • Honam Mathematical Journal
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    • v.38 no.1
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    • pp.47-57
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    • 2016
  • In the discrete formulation of the bubble stabilized Legendre Galerkin methods, the system of equations includes the artificial viscosity term as the parameter. We investigate the estimation of this parameter to get the least-squares solution which minimizes the sum of the squares of errors at each node points. Some numerical results are reported.

Nondestructive Imaging of Subspace Objects by 2D Electrical Resistance Tomography (2차원 전기비저항토모그래피를 이용한 지하물체의 비파괴 영상화)

  • Kim, Ho-Chan;Boo, Chang-Jin;Kim, Se-Ho;Jwa, Chong-Keun;Oh, Seong-Bo;Ko, Bong-Woon;Kim, Moon-Chan;Kim, Yong-Seok
    • Proceedings of the KIEE Conference
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    • 2005.07d
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    • pp.2619-2621
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    • 2005
  • Electrical resistance tomography(ERT) maps resistivity values of the soil subsurface and characterizes buried objects. The characterization includes location, size, and resistivity of buried objects. In this paper, Gauss-Newton and truncated least squares(TLS) are presented for the solution of the ERT image reconstruction. Computer simulations show that the spatial resolution of the reconstructed images by the TLS approach is improved as compared to that obtained by the Gauss-Newton method.

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UAV(Unmanned Aerial Vehicle) image stabilization algorithm based on estimating averaged vehicle motion (기체의 평균 움직임 추정에 기반한 무인항공기 영상 안정화 알고리즘)

  • Lee, Hong-Suk;Ko, Yun-Ho;Kim, Byoung-Soo
    • Proceedings of the IEEK Conference
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    • 2009.05a
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    • pp.216-218
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    • 2009
  • This paper proposes an image processing algorithm to stabilize shaken scenes of UAV(Unmanned Aerial Vehicle) caused by vehicle self-vibration and aerodynamic disturbance. The proposed method stabilizes images by compensating estimated shake motion which is evaluated from global motion. The global motion between two continuous images modeled by 6 parameter warping model is estimated by non-linear square method based on Gauss-Newton algorithm with excluding outlier region. The shake motion is evaluated by subtracting the global motion from aerial vehicle motion obtained by averaging global motion. Experimental results show that the proposed method stabilize shaken scenes effectively.

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Error Analysis of Time-Based and Angle-Based Location Methods (시간기반과 각도기반의 측위방식 성능비교 및 오차 특성 분석)

  • Kim Dong-Hyeok;Song Seung-Hun;Sung Tae-Kyung
    • Journal of Institute of Control, Robotics and Systems
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    • v.12 no.10
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    • pp.962-967
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    • 2006
  • Indoor positioning is highlighted recently, and various kinds of indoor positioning systems are under developments. Since positioning systems have their own characteristics, proper positioning scheme should be chosen according to the required specifications. Positioning methods are classified into time-based and angle-based one. This paper presents the error analysis of time-based and angle-based location methods. Because measurements of these methods are nonlinear, linearizations are needed in both cases to estimate the user position. In the linearization, Gauss-Newton method is used in both cases. To analyze the position error, we investigate the error ellipse parameters that include eccentricity, rotation angle, and the size of ellipse. Simulation results show that the major axes of TOA and AOA method lie in different quadrants at most region of workspace, especially where the geometry is poor. When the TOA/AOA hybrid is employed, it is found that the error ellipse is reduced to the intersection of ellipses of TOA and AOA.

Image Reconstruction of Subspace Object Using Electrical Resistance Tomography

  • Boo Chang-Jin;Kim Ho-Chan;Kang Min-Jae
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.6 no.1
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    • pp.47-51
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    • 2006
  • Electrical resistance tomograpy (ERT) maps resistivity values of the soil subsurface and characterizes buried objects. The characterization includes location, size, and resistivity of buried objects. In this paper, truncated least squares (TLS) is presented for the solution of the ERT image reconstruction. Results of numerical experiments in ERT solved by the TLS approach is presented and compared to that obtained by the Gauss-Newton method.

Development of an AOA Location Method Using Covariance Estimation

  • Lee, Sung-Ho;Roh, Gi-Hong;Sung, Tae-Kyung
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.485-489
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    • 2006
  • In last decades, several linearization methods for the AOA measurements have been proposed, for example, Gauss-Newton method and closed-form solution. Gauss-Newton method can achieve high accuracy, but the convergence of the iterative process is not always ensured if the initial guess is not accurate enough. Closed-form solution provides a non-iterative solution and it is less computational. It does not suffer from convergence problem, but estimation error is somewhat larger. This paper proposes a self-tuning weighted least square AOA algorithm that is a modified version of the conventional closed-form solution. In order to estimate the error covariance matrix as a weight, two-step estimation technique is used. Simulation results show that the proposed method has smaller positioning error compared to the existing methods.

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Parameter Identification for the Tractor Dynamic Model by use of a Forced Vibration Experiment

  • R.Noguchi;O.Kinoshita;E.Inoue;Na, K.kano
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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    • pp.1117-1126
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    • 1993
  • Physical parameters in the forward direction of the tractor , which mainly affects the vibration characteristics of the tractor dynamic model, were able to be identified in a short time by using the Gauss-Newton method with extremum searching based on the data obtained from a forced vibration experiment. It was clarified that a period for the updating of the parameter estimates method has effects on the convergence accuracy of identification for the spring constant in the forward direction of the tractor.

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