• 제목/요약/키워드: linear model

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Kalman Filter 이론에 의한 하천유역의 선형저수지 모델 (A Linear Reservoir Model with Kslman Filter in River Basin)

  • 이영화
    • 한국환경과학회지
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    • 제3권4호
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    • pp.349-356
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    • 1994
  • The purpose of this study is to develop a linear reservoir model with Kalman filter using Kalman filter theory which removes a physical uncertainty of :ainfall-runoff process. A linear reservoir model, which is the basic model of Kalman filter, is used to calculate runoff from rainfall in river basin. A linear reservoir model with Kalman filter is composed of a state-space model using a system model and a observation model. The state-vector of system model in linear. The average value of the ordinate of IUH for a linear reservoir model with Kalman filter is used as the initial value of state-vector. A .linear reservoir model with Kalman filter shows better results than those by linear reserevoir model, and decreases a physical uncertainty of rainfall-runoff process in river basin.

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선형저수지 모형의 매개변수연구 (A study on Parameters of Linear reservoir models)

  • 고재웅;서영제
    • 물과 미래
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    • 제20권3호
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    • pp.229-235
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    • 1987
  • The purpose of this study is to estimate the parameters of linear reservoir models in order to derive the Instantaneous unit hydrograph from a given small experimental watershed. The linear reservoir model is a conceptual model, consisting of cascade or parallel equal linear reservoirs, preceded by a linear channel which involved Nash, SLR(single linear reservoir) and 2-PLR(two-parallel linear Reservoir) model. the Nash model have two parameters N and K, single linear reseroir has one parameter $K_I$ and two-parallel linear reservoirs have two parameters $K_1,\;K_2$; where N denote the number of reservoirs and K is the storage coefficient of each reservoirs.

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Trajectory Following Control Using Cogging Force Model in Linear Positioning System

  • Chung, Myung-Jin;Gweon, Dae-Gab
    • International Journal of Precision Engineering and Manufacturing
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    • 제3권3호
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    • pp.62-68
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    • 2002
  • To satisfy the requirement of the one axis linear positioning system, which is following control of the desired trajectory without following error and is the high positioning accuracy, feed-forward loop having cogging force model is proposed. In the one axis linear positioning system with linear PM motor, cogging force acting as disturbance is modeled analytically. Analytic model of cogging force is verified by result measured from positioning system constructed with linear PM motor. Measured result is very similar with proposed analytic model. Cogging force model is used as feet forward loop in control scheme of linear positioning system. Cogging force feed-forward'loop is obtained from analytic model of cogging farce. Trajectory following error is reduced from 300nm to 100nm by applying the proposed cogging farce feed-forward loop. By using analytic model of cogging force, the control scheme is simplified. Also this analytic model is applicable to calculation of characteristic value of positioning system in design process.

선형 저수지 유형의 parameter 연구

  • 서영재;고재웅
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 1987년도 제29회 수공학연구발표회논문초록집
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    • pp.151-158
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    • 1987
  • The purpose of thes study is to estimate the parameters of linear reservoir models in order to derive the instantaneous unit hydrograph from a given small experimental watershed. The linear reservoir model is a conceptual model, consisting of cascade or parallel equal linear reservoirs, preceded by a linear channel which involved NASH, SLR(single linear reservoir)and 2-PLR(two-parallel linear reservoir)model. The NASH model have two parameters N and K, single linear reservoir has one parameter K1 and two-parallel linear reservoirs have two parameters K1, K2;where N denote the number of reservoirs and K is the storage coefficient of each reservoirs.

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Large Robust Designs for Generalized Linear Model

  • Kim, Young-Il;Kahng, Myung-Wook
    • Journal of the Korean Data and Information Science Society
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    • 제10권2호
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    • pp.289-298
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    • 1999
  • We consider a minimax approach to make a design robust to many types or uncertainty arising in reality when dealing with non-normal linear models. We try to build a design to protect against the worst case, i.e. to improve the "efficiency" of the worst situation that can happen. In this paper, we especially deal with the generalized linear model. It is a known fact that the generalized linear model is a universal approach, an extension of the normal linear regression model to cover other distributions. Therefore, the optimal design for the generalized linear model has very similar properties as the normal linear model except that it has some special characteristics. Uncertainties regarding the unknown parameters, link function, and the model structure are discussed. We show that the suggested approach is proven to be highly efficient and useful in practice. In the meantime, a computer algorithm is discussed and a conclusion follows.

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Variable Selection Theorems in General Linear Model

  • Yoon, Sang-Hoo;Park, Jeong-Soo
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2005년도 추계 학술발표회 논문집
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    • pp.187-192
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    • 2005
  • For the problem of variable selection in linear models, we consider the errors are correlated with V covariance matrix. Hocking's theorems on the effects of the overfitting and the undefitting in linear model are extended to the less than full rank and correlated error model, and to the ANCOVA model

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Normal Mixture Model with General Linear Regressive Restriction: Applied to Microarray Gene Clustering

  • Kim, Seung-Gu
    • Communications for Statistical Applications and Methods
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    • 제14권1호
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    • pp.205-213
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    • 2007
  • In this paper, the normal mixture model subjected to general linear restriction for component-means based on linear regression is proposed, and its fitting method by EM algorithm and Lagrange multiplier is provided. This model is applied to gene clustering of microarray expression data, which demonstrates it has very good performances for real data set. This model also allows to obtain the clusters that an analyst wants to find out in the fashion that the hypothesis for component-means is represented by the design matrices and the linear restriction matrices.

공간적 상관관계가 존재하는 이산형 자료를 위한 일반화된 공간선형 모형 개관 (Review of Spatial Linear Mixed Models for Non-Gaussian Outcomes)

  • 박진철
    • 응용통계연구
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    • 제28권2호
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    • pp.353-360
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    • 2015
  • 공간적으로 관측되는 연속형 자료를 분석하는 모형으로 공간적 상관관계를 고려한 다양한 정규모형이 지난 수십 년간 제안되었다. 그 중에서 공간효과를 랜덤효과로 모형화하는 공간선형모형(Spatial Linear Mixed Model; SLMM)이 가장 널리 활용되는 모형 중 하나일 것이다. 연결함수(link function)을 사용하면 SLMM을 비정규 데이터도 적용할 수 있는 일반화된 공간선형모형(Spatial Generalized Linear Mixed Model; SGLMM)으로 자연스럽게 확장할 수 있다. 이 논문에서는 가장 널리 활용되는 SGLMM을 알아보고 실제 데이터 적용사례를 R 패키지를 활용하여 제시하고자 한다.

선형 부착성 점탄성 접촉모형의 DEM 적용 및 해석적 방법을 이용한 검증 (Implementation and Verification of Linear Cohesive Viscoelastic Contact Model for Discrete Element Method)

  • 윤태영;유평준
    • 한국도로학회논문집
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    • 제17권4호
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    • pp.25-31
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    • 2015
  • PURPOSES: Implementation and verification of the simple linear cohesive viscoelastic contact model that can be used to simulate dynamic behavior of sticky aggregates. METHODS: The differential equations were derived and the initial conditions were determined to simulate a free falling ball with a sticky surface from a ground. To describe this behavior, a combination of linear contact model and a cohesive contact model was used. The general solution for the differential equation was used to verify the implemented linear cohesive viscoelastic API model in the DEM. Sensitivity analysis was also performed using the derived analytical solutions for several combinations of damping coefficients and cohesive coefficients. RESULTS : The numerical solution obtained using the DEM showed good agreement with the analytical solution for two extreme conditions. It was observed that the linear cohesive model can be successfully implemented with a linear spring in the DEM API for dynamic analysis of the aggregates. CONCLUSIONS: It can be concluded that the derived closed form solutions are applicable for the analysis of the rebounding behavior of sticky particles, and for verification of the implemented API model in the DEM. The assumption of underdamped condition for the viscous behavior of the particles seems to be reasonable. Several factors have to be additionally identified in order to develop an enhanced contact model for an asphalt mixture.

Validation of a non-linear hinge model for tensile behavior of UHPFRC using a Finite Element Model

  • Mezquida-Alcaraz, Eduardo J.;Navarro-Gregori, Juan;Lopez, Juan Angel;Serna-Ros, Pedro
    • Computers and Concrete
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    • 제23권1호
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    • pp.11-23
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    • 2019
  • Nowadays, the characterization of Ultra-High Performance Fiber-Reinforced Concrete (UHPFRC) tensile behavior still remains a challenge for researchers. For this purpose, a simplified closed-form non-linear hinge model based on the Third Point Bending Test (ThirdPBT) was developed by the authors. This model has been used as the basis of a simplified inverse analysis methodology to derive the tensile material properties from load-deflection response obtained from ThirdPBT experimental tests. In this paper, a non-linear finite element model (FEM) is presented with the objective of validate the closed-form non-linear hinge model. The state determination of the closed-form model is straightforward, which facilitates further inverse analysis methodologies to derive the tensile properties of UHPFRC. The accuracy of the closed-form non-linear hinge model is validated by a robust non-linear FEM analysis and a set of 15 Third-Point Bending tests with variable depths and a constant slenderness ratio of 4.5. The numerical validation shows excellent results in terms of load-deflection response, bending curvatures and average longitudinal strains when resorting to the discrete crack approach.