• Title/Summary/Keyword: weighted function

검색결과 747건 처리시간 0.037초

An inverse approach based on uniform load surface for damage detection in structures

  • Mirzabeigy, Alborz;Madoliat, Reza
    • Smart Structures and Systems
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    • 제24권2호
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    • pp.233-242
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    • 2019
  • In this paper, an inverse approach based on uniform load surface (ULS) is presented for structural damage localization and quantification. The ULS is excellent approximation for deformed configuration of a structure under distributed unit force applied on all degrees of freedom. The ULS make use of natural frequencies and mode shapes of structure and in mathematical point of view is a weighted average of mode shapes. An objective function presented to damage detection is discrepancy between the ULS of monitored structure and numerical model of structure. Solving this objective function to find minimum value yields damage's parameters detection. The teaching-learning based optimization algorithm has been employed to solve inverse problem. The efficiency of present damage detection method is demonstrated through three numerical examples. By comparison between proposed objective function and another objective function which make use of natural frequencies and mode shapes, it is revealed present objective function have faster convergence and is more sensitive to damage. The method has good robustness against measurement noise and could detect damage by using the first few mode shapes. The results indicate that the proposed method is reliable technique to damage detection in structures.

A Novel Algorithm of Joint Probability Data Association Based on Loss Function

  • Jiao, Hao;Liu, Yunxue;Yu, Hui;Li, Ke;Long, Feiyuan;Cui, Yingjie
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제15권7호
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    • pp.2339-2355
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    • 2021
  • In this paper, a joint probabilistic data association algorithm based on loss function (LJPDA) is proposed so that the computation load and accuracy of the multi-target tracking algorithm can be guaranteed simultaneously. Firstly, data association is divided in to three cases based on the relationship among validation gates and the number of measurements in the overlapping area for validation gates. Also the contribution coefficient is employed for evaluating the contribution of a measurement to a target, and the loss function, which reflects the cost of the new proposed data association algorithm, is defined. Moreover, the equation set of optimal contribution coefficient is given by minimizing the loss function, and the optimal contribution coefficient can be attained by using the Newton-Raphson method. In this way, the weighted value of each target can be achieved, and the data association among measurements and tracks can be realized. Finally, we compare performances of LJPDA proposed and joint probabilistic data association (JPDA) algorithm via numerical simulations, and much attention is paid on real-time performance and estimation error. Theoretical analysis and experimental results reveal that the LJPDA algorithm proposed exhibits small estimation error and low computation complexity.

FUNCTION APPROXIMATION OVER TRIANGULAR DOMAIN USING CONSTRAINED Legendre POLYNOMIALS

  • Ahn, Young-Joon
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제9권2호
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    • pp.99-106
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    • 2005
  • We present a relation between the orthogonality of the constrained Legendre polynomials over the triangular domain and the BB ($B{\acute{e}zier}\;-Bernstein$) coefficients of the polynomials using the equivalence of orthogonal complements. Using it we also show that the best constrained degree reduction of polynomials in BB form equals the best approximation of weighted Euclidean norm of coefficients of given polynomial in BB form from the coefficients of polynomials of lower degree in BB form.

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Regression Quantile Estimations on Censored Survival Data

  • 심주용
    • Journal of the Korean Data and Information Science Society
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    • 제13권2호
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    • pp.31-38
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    • 2002
  • In the case of multiple survival times which might be censored at each covariate vector, we study the regression quantile estimations in this paper. The estimations are based on the empirical distribution functions of the censored times and the sample quantiles of the observed survival times at each covariate vector and the weighted least square method is applied for the estimation of the regression quantile. The estimators are shown to be asymptotically normally distributed under some regularity conditions.

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ON DISTANCE ESTIMATES AND ATOMIC DECOMPOSITIONS IN SPACES OF ANALYTIC FUNCTIONS ON STRICTLY PSEUDOCONVEX DOMAINS

  • Arsenovic, Milos;Shamoyan, Romi F.
    • 대한수학회보
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    • 제52권1호
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    • pp.85-103
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    • 2015
  • We prove some sharp extremal distance results for functions in various spaces of analytic functions on bounded strictly pseudoconvex domains with smooth boundary. Also, we obtain atomic decompositions in multifunctional Bloch and weighted Bergman spaces of analytic functions on strictly pseudoconvex domains with smooth boundary, which extend known results in the classical case of a single function.

고분해능의 주파수 추정 알고리즘 개발 (High Resolution Frequency Estimation of Real Sinusoids)

  • 서인용
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.279-282
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    • 2003
  • In this paper, we propose a new high resolution frequency estimator for real sinusoids by using short time data and the AWLS/MFT (Adaptive Weighted Least Squares/ Modulation Function Technique) algorithm. Monte-Carlo simulations verify better performances of the proposed frequency estimator and demonstrate that the proposed AWLS sinusoidal estimator is a high resolution estimator.

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패킷 손실을 고려한 네트워크 제어 시스템의 안정성 분석 (Stability Analysis of Networked Control Systems with Packet Dropouts)

  • 김재만;박진배;최윤호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1731_1732
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    • 2009
  • This paper presents a stability analysis of networked control systems with packet dropouts. The packet dropouts are modeled as a linear function of the stochastic variable satisfying Bernoulli random binary distribution and weighted moving average (WMA). The observer based controller scheme is designed to exponentially mean square stabilize the NCS. Simulation results is provided to show the applicability of the proposed method.

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Exact Variance of Location Estimator in One-Way Random Effect Models with Two Distint Group Sizes

  • Lee, Young-Jo;Chung, Han-Yeong
    • Journal of the Korean Statistical Society
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    • 제18권2호
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    • pp.118-124
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    • 1989
  • In the one-way random effect model, we often estimate the variance components by the ANOVA method and then estimate the population mean. Whe there are only two distint group sizes, the conventional mean estimator is represented as a weighted average of two normal means with weights being the function of variance component estimators. In this paper, we will study a method which can compute the exact variance of the mean estimator when we set the negative variance component estimate to zero.

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냉간압연 공정에서의 출측 판두께제어 (Exit strip gauge control for a cold rolling process)

  • 류석환
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.525-530
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    • 1992
  • This paper deals with an exit strip gauge controller design for a cold rolling mill process with one input and two outputs. In order to attenuate the exit strip gauge variation caused by the Back-up roll eccentricity and the entry guage variation, an H$_{\infty}$ controller design methodology is used to keep the frequency weighted mixed sensitivity function small. Effectiveness of the proposed controller is demonstrated by a computer simulation..

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