• 제목/요약/키워드: generalized least squares method

검색결과 98건 처리시간 0.023초

일반화된 이동최소자승법과 이를 이용한 얇은 보의 무요소 해석 (Generalized Moving Least Squares Method and its use in Meshless Analysis of Thin Beam)

  • 조진연
    • 한국전산구조공학회:학술대회논문집
    • /
    • 한국전산구조공학회 2002년도 봄 학술발표회 논문집
    • /
    • pp.497-504
    • /
    • 2002
  • In meshless methods, the moving least squares approximation technique is widely used to approximate a solution space because of its useful numerical characters such as non-element approximation, easily controllable smoothness, and others. In this work, a generalized version of the moving least squares method Is introduced to enhance the approximation performance through the Information converning to the derivative of the field variable. The results of numerical tests for approximation verify the improved accuracy of the generalized meshless approximation procedure compared to the conventional moving least squares method. By using this generalized moving least squares method, meshless analysis of thin beam is carried out, and its performance is investigated.

  • PDF

On the generalized truncated least squares adaptive algorithm and two-stage design method with application to adaptive control

  • Yamamoto, Yoshihiro;Nikiforuk, Peter-N.;Gupta, Madam-M.
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
    • /
    • pp.7-12
    • /
    • 1993
  • This paper presents a generalized truncated least, squares adaptive algorithm and a two-stage design method. The proposed algorithm is directly derived from the normal equation of the generalized truncated least squares method (GTLSM). The special case of the GTLSM, the truncated least squares (TLS) adaptive algorithm, has a distinct features which includes the case of minimum steps estimator. This algorithm seemed to be best in the deterministic case. For real applications in the presence of disturbances, the GTLS adaptive algorithm is more effective. The two-stage design method proposed here combines the adaptive control system design with a conventional control design method and each can be treated independently. Using this method, the validity of the presented algorithms are examined by the simulation studies of an indirect adaptive control.

  • PDF

Estimation of Seasonal Cointegration under Conditional Heteroskedasticity

  • Seong, Byeongchan
    • Communications for Statistical Applications and Methods
    • /
    • 제22권6호
    • /
    • pp.615-624
    • /
    • 2015
  • We consider the estimation of seasonal cointegration in the presence of conditional heteroskedasticity (CH) using a feasible generalized least squares method. We capture cointegrating relationships and time-varying volatility for long-run and short-run dynamics in the same model. This procedure can be easily implemented using common methods such as ordinary least squares and generalized least squares. The maximum likelihood (ML) estimation method is computationally difficult and may not be feasible for larger models. The simulation results indicate that the proposed method is superior to the ML method when CH exists. In order to illustrate the proposed method, an empirical example is presented to model a seasonally cointegrated times series under CH.

A Method of Obtaning Least Squares Estimators of Estimable Functions in Classification Linear Models

  • Kim, Byung-Hwee;Chang, In-Hong;Dong, Kyung-Hwa
    • Journal of the Korean Statistical Society
    • /
    • 제28권2호
    • /
    • pp.183-193
    • /
    • 1999
  • In the problem of estimating estimable functions in classification linear models, we propose a method of obtaining least squares estimators of estimable functions. This method is based on the hierarchical Bayesian approach for estimating a vector of unknown parameters. Also, we verify that estimators obtained by our method are identical to least squares estimators of estimable functions obtained by using either generalized inverses or full rank reparametrization of the models. Some examples are given which illustrate our results.

  • PDF

A transductive least squares support vector machine with the difference convex algorithm

  • Shim, Jooyong;Seok, Kyungha
    • Journal of the Korean Data and Information Science Society
    • /
    • 제25권2호
    • /
    • pp.455-464
    • /
    • 2014
  • Unlabeled examples are easier and less expensive to obtain than labeled examples. Semisupervised approaches are used to utilize such examples in an eort to boost the predictive performance. This paper proposes a novel semisupervised classication method named transductive least squares support vector machine (TLS-SVM), which is based on the least squares support vector machine. The proposed method utilizes the dierence convex algorithm to derive nonconvex minimization solutions for the TLS-SVM. A generalized cross validation method is also developed to choose the hyperparameters that aect the performance of the TLS-SVM. The experimental results conrm the successful performance of the proposed TLS-SVM.

Least Squares Approach for Structural Reanalysis

  • Kyung-Joon Cha;Ho-Jong Jang;Dal-Sun Yoon
    • Journal of the Korean Statistical Society
    • /
    • 제25권3호
    • /
    • pp.369-379
    • /
    • 1996
  • A study is made of approximate technique for structural reanalysis based on the force method. Perturbntion analysis of generalized least squares problem is adopted to reanalyze a damaged structure, and related results are presented.

  • PDF

A Generalized Partly-Parametric Additive Risk Model

  • Park, Cheol-Yong
    • Journal of the Korean Data and Information Science Society
    • /
    • 제17권2호
    • /
    • pp.401-409
    • /
    • 2006
  • We consider a generalized partly-parametric additive risk model which generalizes the partly parametric additive risk model suggested by McKeague and Sasieni (1994). As an estimation method of this model, we propose to use the weighted least square estimation, suggested by Huffer and McKeague (1991), for Aalen's additive risk model by a piecewise constant risk. We provide an illustrative example as well as a simulation study that compares the performance of our method with the ordinary least squares method.

  • PDF

일반화된 유한차분법을 이용한 균열해석 (A Generalized Finite Difference Method for Crack Analysis)

  • 윤영철;김동조;이상호
    • 한국전산구조공학회:학술대회논문집
    • /
    • 한국전산구조공학회 2007년도 정기 학술대회 논문집
    • /
    • pp.501-506
    • /
    • 2007
  • A generalized finite difference method for solving solid mechanics problems such as elasticity and crack problems is presented. The method is constructed in framework of Taylor polynomial based on the Moving Least Squares method and collocation scheme based on the diffuse derivative approximation. The governing equations are discretized into the difference equations and the nodal solutions are obtained by solving the system of equations. Numerical examples successfully demonstrate the robustness and efficiency of the proposed method.

  • PDF

EXTENSION OF FACTORING LIKELIHOOD APPROACH TO NON-MONOTONE MISSING DATA

  • Kim, Jae-Kwang
    • Journal of the Korean Statistical Society
    • /
    • 제33권4호
    • /
    • pp.401-410
    • /
    • 2004
  • We address the problem of parameter estimation in multivariate distributions under ignorable non-monotone missing data. The factoring likelihood method for monotone missing data, termed by Rubin (1974), is extended to a more general case of non-monotone missing data. The proposed method is algebraically equivalent to the Newton-Raphson method for the observed likelihood, but avoids the burden of computing the first and the second partial derivatives of the observed likelihood. Instead, the maximum likelihood estimates and their information matrices for each partition of the data set are computed separately and combined naturally using the generalized least squares method.

LEAST SQUARES SOLUTIONS OF THE MATRIX EQUATION AXB = D OVER GENERALIZED REFLEXIVE X

  • Yuan, Yongxin
    • Journal of applied mathematics & informatics
    • /
    • 제26권3_4호
    • /
    • pp.471-479
    • /
    • 2008
  • Let $R\;{\in}\;C^{m{\times}m}$ and $S\;{\in}\;C^{n{\times}n}$ be nontrivial unitary involutions, i.e., $R^*\;=\;R\;=\;R^{-1}\;{\neq}\;I_m$ and $S^*\;=\;S\;=\;S^{-1}\;{\neq}\;I_m$. We say that $G\;{\in}\;C^{m{\times}n}$ is a generalized reflexive matrix if RGS = G. The set of all m ${\times}$ n generalized reflexive matrices is denoted by $GRC^{m{\times}n}$. In this paper, an efficient method for the least squares solution $X\;{\in}\;GRC^{m{\times}n}$ of the matrix equation AXB = D with arbitrary coefficient matrices $A\;{\in}\;C^{p{\times}m}$, $B\;{\in}\;C^{n{\times}q}$and the right-hand side $D\;{\in}\;C^{p{\times}q}$ is developed based on the canonical correlation decomposition(CCD) and, an explicit formula for the general solution is presented.

  • PDF