• 제목/요약/키워드: Parameter Estimations

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LED 칩 열화특성에 적합한 열화모델 기반의 수명예측 시스템 구현

  • 유기훈;이재훈;김달석;이무석;윤양기;한지훈;장중순
    • 한국신뢰성학회:학술대회논문집
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    • 한국신뢰성학회 2011년도 춘계학술발표대회 논문집
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    • pp.79-85
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    • 2011
  • LED(Light Emitting Diode) is a powerful device used in applications as diverse as replacements for aviation lighting, automotive lighting as well as in traffic signals. This study is to propose a prediction system based on the degradation model of LED which is determined by combining scale and shape parameter. The degradation model is analysed goodness of fit test using calculated R-square, and is compared with previous models. A LED prediction system using degradation model is developed to automate estimations of degradation parameters and lifetimes.

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2-모수 파레토분포의 객관적 베이지안 추정 (Objective Bayesian Estimation of Two-Parameter Pareto Distribution)

  • 손영숙
    • 응용통계연구
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    • 제26권5호
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    • pp.713-723
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    • 2013
  • 본 연구에서는 2-모수 파레토분포에 대해 무정보사전분포인 준거사전분포의 가정 하에서 객관적 베이지안 모수추정 절차를 제안하였다. 베이지안 추정은 깁스샘플링에 의해서 수행된다. 깁스샘플러에서 모수생성하는 방법은 형태모수는 감마분포로부터 생성하고 척도모수는 적응기각표집 알고리즘에 의해 생성한다. 제안된 베이지안 모수추정 절차는 모의실험과 자료분석에서 기존의 추정방법들인 L-적률추정법, 최우추정법, 공액사전분포 하의 주관적 베이지안 모수추정법과 비교된다.

Estimations in a skewed uniform distribution

  • Son, Hee-Ju;Woo, Jung-Soo
    • Journal of the Korean Data and Information Science Society
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    • 제20권4호
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    • pp.733-740
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    • 2009
  • We obtain a skewed uniform distribution by a uniform distribution, and evaluate its coeffcient of skewness. And we obtain the approximate maximum likelihood estimator (AML) and moment estimator of skew parameter in the skewed uniform distribution. And we compare simulated mean squared errors (MSE) of those estimators, and also compare MSE of two proposed reliability estimators in two independent skewed uniform distributions each with different skew parameters.

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Estimations of the Minimum and Maximum for Two Generalized Uniform Scale Parameters

  • Lee, Chang-Soo;Kim, Joong-Dae
    • Communications for Statistical Applications and Methods
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    • 제6권1호
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    • pp.319-326
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    • 1999
  • We shall derive several estimators for the minimum and maximum of two generalized uniform scale parameters with a common known shape parameter when the order of the scales is unknown and sample sizes are equal. Also we shall obtain the biases and mean squared errors for the proposed several estimators and compare numerically performances for the preposed several estimators.

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Inference on P(Y

  • Kim, Joong-Dae;Moon, Yeung-Gil;Kang, Jun-Ho
    • Journal of the Korean Data and Information Science Society
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    • 제14권4호
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    • pp.989-995
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    • 2003
  • Inference for probability P(Y

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Bayesian Estimations of the Smaller and Larger for Two Pareto Scale Parameters

  • Woo, Jungsoo;Lee, Changsoo
    • Communications for Statistical Applications and Methods
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    • 제7권3호
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    • pp.829-836
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    • 2000
  • We shall derive Bayes estimators for he smaller and larger of two Pareto scale parameters with a common known shape parameter when the order of the scales is unknown and sample sizes are equal under squared error loss function. Also, we shall obtain biases and man squared errors for proposed Bayes estimators, and compare numerically performances for the proposed Bayes estimators.

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순차적 예측오차 방법에 의한 구조물의 모우드 계수 추정 (IDENTIFICATION OF MODAL PARAMETERS BY SEQUENTIAL PREDICTION ERROR METHOD)

  • Lee, Chang-Guen;Yun, Chung-Bang
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1990년도 가을 학술발표회 논문집
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    • pp.79-84
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    • 1990
  • The modal parameter estimations of linear multi-degree-of-freedom structural dynamic systems are carried out in time domain. For this purpose, the equation of motion is transformed into the autoregressive and moving average model with auxiliary stochastic input (ARMAX) model. The parameters of the ARMAX model are estimated by using the sequential prediction error method. Then, the modal parameters of the system are obtained thereafter. Experimental results are given for a 3-story building model subject to ground exitations.

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대규모 연결계의 분산상태관측기 설계 (Design of Decentralized State Observer for Large Scale Interconnected System)

  • 이기상;장민도
    • 대한전기학회논문지
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    • 제37권2호
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    • pp.122-129
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    • 1988
  • A design method of decentralized state observer for large scale interconnected systems is proposed by the use of interconnection rejection approach and interconnection modelling technique. The proposed design method is developed based on the interconnection partitioning. Therefore partitioning conditions are suggested. And the conditions for observer pole assignment and observer parameter determination procedures are described for possible interconnection patterns. The decentralized state observer gives good estimates without any information on the interconnection variables and estimations. In addition, a numerical example is given to explain the design procedures and to show the estimation performance of the decentralized observer.

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기술상호효과분석의 입력변수 추정 난이도 경감을 위한 입력변수 설정모형의 설계 (Designing an Input Parameters Setting Model for Reducing the Difficulty of Input Parameters Estimations in Cross Impact Analysis)

  • 전정철;권철신
    • 한국경영과학회지
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    • 제42권2호
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    • pp.35-48
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    • 2017
  • As the technology convergence paradigm emerges, the need for "CIA techniques" to analyze the mutual effects of technology is increasing. However, since the CIA input parameter estimation is difficult, the present study suggests a "CIA input parameter setting model" to alleviate the difficulty of CIA input parameter estimation. This paper is focused on the difference of measurement difficulty by each scale which expert's estimation behavior was defined as measurement activity quantifying the judgment of future technology. Therefore, this model is designed to estimate the input variable as a sequence or isometric scale that is relatively easy to measure, and then converts it into a probability value. The input parameter setting model of the CIA technique consists of three sub-models : 'probability value derivation model', 'influence estimation model', and 'impact value calculation model', in order to develop a series of models the Thurstone V model, Regression Analysis, etc has been used.

A Review of Li-ion Battery Equivalent Circuit Models

  • Zhang, Xiaoqiang;Zhang, Weiping;Lei, Geyang
    • Transactions on Electrical and Electronic Materials
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    • 제17권6호
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    • pp.311-316
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    • 2016
  • Batteries are critical components of electric vehicles and energy storage systems. The connection of a battery to the power grid for charge and discharge greatly affects energy storage. Therefore, an accurate and easy-to-observe battery model should be established to achieve systematic design, simulation, and SOC (state of charge) estimations. In this review, several equivalent circuit models of representative significance are explained, and their respective advantages and disadvantages are compared to determine and outline their reasonable applications to Li-ion batteries. Numerous commonly used model parameter identification principles are summarized as well, and basic model verification methods are briefly introduced for the convenient use of such models.