• Title/Summary/Keyword: Linear model

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다중선형회귀법을 활용한 예민화와 환경변수에 따른 AL-6XN강의 공식특성 예측 (Prediction of Pitting Corrosion Characteristics of AL-6XN Steel with Sensitization and Environmental Variables Using Multiple Linear Regression Method)

  • 정광후;김성종
    • Corrosion Science and Technology
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    • 제19권6호
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    • pp.302-309
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    • 2020
  • This study aimed to predict the pitting corrosion characteristics of AL-6XN super-austenitic steel using multiple linear regression. The variables used in the model are degree of sensitization, temperature, and pH. Experiments were designed and cyclic polarization curve tests were conducted accordingly. The data obtained from the cyclic polarization curve tests were used as training data for the multiple linear regression model. The significance of each factor in the response (critical pitting potential, repassivation potential) was analyzed. The multiple linear regression model was validated using experimental conditions that were not included in the training data. As a result, the degree of sensitization showed a greater effect than the other variables. Multiple linear regression showed poor performance for prediction of repassivation potential. On the other hand, the model showed a considerable degree of predictive performance for critical pitting potential. The coefficient of determination (R2) was 0.7745. The possibility for pitting potential prediction was confirmed using multiple linear regression.

전차륜조향 굴절차량의 안내제어를 위한 횡방향 동역학 모델 (Lateral Dynamic Model of an All-Wheel Steered Articulated Vehicle for Guidance Control)

  • 윤경한;김영철;민경득;변윤섭
    • 전기학회논문지
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    • 제60권6호
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    • pp.1229-1238
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    • 2011
  • This paper deals with the lateral dynamic model of an all-wheel steered articulated vehicle to design a guidance controller. Nonlinear dynamic model of articulated vehicle is developed by complementing the model about the BRT system of California PATH in U. S. A. and the Phileas system of the APTS in Netherlands. Linear lateral dynamic model has been derived from the nonlinear dynamic model under some assumptions associated with the driving conditions. To design a guidance controller, we derive a transfer function that is steering angle as input and lateral acceleration as output from the linear lateral dynamic model by applying the parameter of vehicle that is developed by Korea Railroad Research Institute. To validate the dynamic model, nonlinear dynamic model has been compared with a vehicle model that has been programmed in ADAMS, and linear dynamic model has been compared with a nonlinear dynamic model under sime assumptions.

Interval Estimation for Sum of Variance Components in a Simple Linear Regression Model with Unbalanced Nested Error Structure

  • Park, Dong-Joon
    • Communications for Statistical Applications and Methods
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    • 제10권2호
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    • pp.361-370
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    • 2003
  • Those who are interested in making inferences concerning linear combination of valiance components in a simple linear regression model with unbalanced nested error structure can use the confidence intervals proposed in this paper. Two approximate confidence intervals for the sum of two variance components in the model are proposed. Simulation study is peformed to compare the methods. The methods are applied to a numerical example and recommendations are given for choosing a proper interval.

유역특성에 따른 탱크모형 매개변수의 변화 (An Evaluatiou of Parameter Variations for a Linear Reservoir (TANK) Model with Watershed Characteristics)

  • 김현영;박승우
    • 한국농공학회지
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    • 제28권2호
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    • pp.42-52
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    • 1986
  • This study involves the estimation of optimal ranges of parameters for a linear watershed model. A well-known TANK model was chosen and a linear combination of four tanks assumed. The model was used to simulate daily streamflow for six watersheds of different sizes and by a trial-and-error approach a set of optimal parameters defined. The parameters were related to watershed sizes and land use conditions. Optimal parameters for ungaged conditions were defined from the relationships; daily streamflow simulated and compared to the observed date. The simulated results were in a general agreement with the data.

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Fuzzy regression using regularlization method based on Tanaka's model

  • Hong Dug-Hun;Kim Kyung-Tae
    • 한국지능시스템학회논문지
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    • 제16권4호
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    • pp.499-505
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    • 2006
  • Regularlization approach to regression can be easily found in Statistics and Information Science literature. The technique of regularlization was introduced as a way of controlling the smoothness properties of regression function. In this paper, we have presented a new method to evaluate linear and non-linear fuzzy regression model based on Tanaka's model using the idea of regularlization technique. Especially this method is a very attractive approach to model non -linear fuzzy data.

Confidence Interval For Sum Of Variance Components In A Simple Linear Regression Model With Unbalanced Nested Error Structure

  • Park, Dong-Joon
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2003년도 춘계 학술발표회 논문집
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    • pp.75-78
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    • 2003
  • Those who are interested in making inferences concerning linear combination of variance components in a simple linear regression model with unbalanced nested error structure can use the confidence intervals proposed in this paper. Two approximate confidence intervals for the sum of two variance components in the model are proposed. Simulation study is peformed to compare the methods.

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A STUDY ON PREDICTION INTERVALS, FACTOR ANALYSIS MODELS AND HIGH-DIMENSIONAL EMPIRICAL LINEAR PREDICTION

  • Jee, Eun-Sook
    • Journal of applied mathematics & informatics
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    • 제14권1_2호
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    • pp.377-386
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    • 2004
  • A technique that provides prediction intervals based on a model called an empirical linear model is discussed. The technique, high-dimensional empirical linear prediction (HELP), involves principal component analysis, factor analysis and model selection. HELP can be viewed as a technique that provides prediction (and confidence) intervals based on a factor analysis models do not typically have justifiable theory due to nonidentifiability, we show that the intervals are justifiable asymptotically.

Constant Error Variance Assumption in Random Effects Linear Model

  • Ahn, Chul-Hwan
    • Communications for Statistical Applications and Methods
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    • 제2권2호
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    • pp.296-302
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    • 1995
  • When heteroscedasticity occurs in random effects linear model, the error variance may depend on the values of one or more of the explanatory variables or on other relevant quantities such as time or spatial ordering. In this paper we derive a score test as a diagnostic tool for detecting non-constant error variance in random effefts linear model based on the model expansion on error variance. This score test is compared to loglikelihood ratio test.

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Comparison of Confidence Intervals on Variance Component In a Simple Linear Regression Model with Unbalanced Nested Error Structure

  • Park, Dong Joon;Park, Sun-Young;Han, Man-Ho
    • Communications for Statistical Applications and Methods
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    • 제9권2호
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    • pp.459-471
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    • 2002
  • In applications using a linear regression model with nested error structure, one might be interested in making inferences concerning variance components. This article proposes approximate confidence intervals on the variance component of the primary level in a simple linear regression model with an unbalanced nested error structure. The intervals are compared using computer simulation and recommendations are provided for selecting an appropriate interval.

A Score Test for Detection of Outliers in Generalized Linear Models

  • Kahng, Myung-Wook;Kim, Min-Kyung
    • Journal of the Korean Data and Information Science Society
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    • 제15권1호
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    • pp.129-139
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    • 2004
  • We consider the problem of testing for outliers in generalized linear model. We proceed by first specifying a mean shift outlier model, assuming the suspect set of ourliers is known. Given this model, we discuss standard approaches to obtaining score test for outliers as an alternative to the likelihood ratio test.

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