• Title/Summary/Keyword: Nonlinear least square

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THE STRONG CONSISTENCY OF THE ASYMMETRIC LEAST SQUARES ESTIMATORS IN NONLINEAR CENSORED REGRESSION MODELS

  • Choi, Seung-Hoe;Kim, Hae-Kyung
    • Communications of the Korean Mathematical Society
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    • v.18 no.4
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    • pp.703-712
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    • 2003
  • This paper deals with the strong consistency of the asymmetric least squares for the nonlinear censored regression models which includes dependent variables cut off midway by any of external conditions, and provide the sufficient conditions which ensure the strong consistency of proposed estimators of the censored regression models. One example is given to illustrate the application of the main result.

Development of Nonlinear Fatigue Model Based on Particle Filter Method (파티클 필터기법을 통한 비선형 피로모델 개발 연구)

  • Mun, Sungho
    • International Journal of Highway Engineering
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    • v.18 no.4
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    • pp.63-68
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    • 2016
  • PURPOSES : The nonlinear model of fatigue cracking is typically used for determining the maintenance period. However, this requires that the model parameters be known. In this study, the particle filter (PF) method was used to determine various statistical parameters such as the mean and standard deviation values for the nonlinear model of fatigue cracking. METHODS : The PF method was used to determine various statistical parameters for the nonlinear model of fatigue cracking, such as the mean and standard deviation. RESULTS : On comparing the values obtained using the PF method and the least square (LS) method, it was found that PF method was suitable for determining the statistical parameters to be used in the nonlinear model of fatigue cracking. CONCLUSIONS : The values obtained using the PF method were as accurate as those obtained using the LS method. Furthermore, reliability design can be applied because the statistical parameters of mean and standard deviation can be obtained through the PF method.

A Controlled Neural Networks of Nonlinear Modeling with Adaptive Construction in Various Conditions (다변 환경 적응형 비선형 모델링 제어 신경망)

  • Kim, Jong-Man;Sin, Dong-Yong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07b
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    • pp.1234-1238
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    • 2004
  • A Controlled neural networks are proposed in order to measure nonlinear environments in adaptive and in realtime. The structure of it is similar to recurrent neural networks: a delayed output as the input and a delayed error between tile output of plant and neural networks as a bias input. In addition, we compute the desired value of hidden layer by an optimal method instead of transfering desired values by backpropagation and each weights are updated by RLS(Recursive Least Square). Consequently, this neural networks are not sensitive to initial weights and a learning rate, and have a faster convergence rate than conventional neural networks. This new neural networks is Error Estimated Neural Networks. We can estimate nonlinear models in realtime by the proposed networks and control nonlinear models. To show the performance of this one, we have various experiments. And this controller call prove effectively to be control in the environments of various systems.

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Nonlinear Neural Networks for Vehicle Modeling Control Algorithm based on 7-Depth Sensor Measurements (7자유도 센서차량모델 제어를 위한 비선형신경망)

  • Kim, Jong-Man;Kim, Won-Sop;Sin, Dong-Yong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.525-526
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    • 2008
  • For measuring nonlinear Vehicle Modeling based on 7-Depth Sensor, the neural networks are proposed m adaptive and in realtime. The structure of it is similar to recurrent neural networks; a delayed output as the input and a delayed error between the output of plant and neural networks as a bias input. In addition, we compute the desired value of hidden layer by an optimal method instead of transfering desired values by backpropagation and each weights are updated by RLS(Recursive Least Square). Consequently, this neural networks are not sensitive to initial weights and a learning rate, and have a faster convergence rate than conventional neural networks. This new neural networks is Error Estimated Neural Networks. We can estimate nonlinear models in realtime by the proposed networks and control nonlinear models.

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THE CONSISTENCY OF NONLINEAR REGRESSION MINIMIZING $L_p$-NORM

  • Choi, Seung-Hoe;Park, Kyung-Ok
    • East Asian mathematical journal
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    • v.14 no.2
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    • pp.421-427
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    • 1998
  • In this paper we provide sufficient conditions which ensure the strong consistency of $L_p$-norm estimation in nonlinear regression model when the probability distribution of the errors term is symmetric about zero. The least absolute deviation and least square estimation are discussed as special cases of the proposed estimation.

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On-line Modeling for Nonlinear Process Systems using the Adaptive Fuzzy-Neural Network (적응 퍼지-뉴럴 네트워크를 이용한 비선형 공정의 On-line 모델링)

  • Park, Chun-Seong;Oh, Sung-Kwun;Kim, Hyun-Ki
    • Proceedings of the KIEE Conference
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    • 1998.11b
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    • pp.537-539
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    • 1998
  • In this paper, we construct the on-line model structure for the nonlinear process systems using the adaptive fuzzy-neural network. Adaptive fuzzy-neural network usually consists of two distinct modifiable structure, with both, the premise and the consequent part. These two parts can be adapted by different optimization methods, which are the hybrid learning procedure combining gradient descent method and least square method. To achieve the on-line model structure, we use the recursive least square method for the consequent parameter identification of nonlinear process. We design the interface between PLC and main computer, and construct the monitoring and control simulator for the nonlinear process. The proposed on-line modeling to real process is carried out to obtain the effective and accurate results.

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Parameter Identification of Robot Hand Tracking Model Using Optimization (최적화 기법을 이용한 로봇핸드 트래킹 모델의 파라미터 추정)

  • Lee, Jong-Kwang;Lee, Hyo-Jik;Yoon, Kwang-Ho;Park, Byung-Suk;Yoon, Ji-Sup
    • Journal of Institute of Control, Robotics and Systems
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    • v.13 no.5
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    • pp.467-473
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    • 2007
  • In this paper, we present a position-based robot hand tracking scheme where a pan-tilt camera is controlled such that a robot hand is always shown in the center of an image frame. We calculate the rotation angles of a pan-tilt camera by transforming the coordinate systems. In order to identify the model parameters, we applied two optimization techniques: a nonlinear least square optimizer and a particle swarm optimizer. From the simulation results, it is shown that the considered parameter identification problem is characterized by a highly multimodal landscape; thus, a global optimization technique such as a particle swarm optimization could be a promising tool to identify the model parameters of a robot hand tracking system, whereas the nonlinear least square optimizer often failed to find an optimal solution even when the initial candidate solutions were selected close to the true optimum.

Nonlinear Channel Equalization Using Adaptive Neuro-Fuzzy Fiter (적응 뉴로-퍼지 필터를 이용한 비선형 채널 등화)

  • 김승석;곽근창;김성수;전병석;유정웅
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.366-366
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    • 2000
  • In this paper, an adaptive neuro-fuzzy filter using the conditional fuzzy c-means(CFCM) methods is proposed. Usualy, the number of fuzzy rules exponentially increases by applying the grid partitioning of the input space, in conventional adaptive neuro-fuzzy inference system(ANFIS) approaches. In order to solve this problem, CFCM method is adopted to render the clusters which represent the given input and output data. Parameter identification is performed by hybrid learning using back-propagation algorithm and total least square(TLS) method. Finally, we applied the proposed method to the nonlinear channel equalization problem and obtained a better performance than previous works.

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Asymptotic Properties of Regression Quanties Estimators in Nonlinear Models (비선형최소분위추정량의 점근적 성질)

  • Choi, Seung-Hoe;Kim, Tae-Soo;Park, Kyung-Ok
    • Journal of the Korean Data and Information Science Society
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    • v.11 no.2
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    • pp.235-245
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    • 2000
  • In this paper, we consider the Regression Quantiles Estimators in nonlinear regression models. This paper provides the sufficient conditions for strong consistency and asymptotic normality of proposed estimation and drives asymptotic relative efficiency of proposed estimatiors with least square estimation. We give some examples and results of Monte Carlo simulation to compare least square and regression quantile estimators.

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A Estimated Neural Networks for Adaptive Cognition of Nonlinear Road Situations (굴곡있는 비선형 도로 노면의 최적 인식을 위한 평가 신경망)

  • Kim, Jong-Man;Kim, Young-Min;Hwang, Jong-Sun;Sin, Dong-Yong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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    • pp.573-577
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    • 2002
  • A new estimated neural networks are proposed in order to measure nonlinear road environments in realtime. This new neural networks is Error Estimated Neural Networks. The structure of it is similar to recurrent neural networks; a delayed output as the input and a delayed error between the output of plant and neural networks as a bias input. In addition, we compute the desired value of hidden layer by an optimal method instead of transfering desired values by backpropagation and each weights are updated by RLS(Recursive Least Square). Consequently, this neural networks are not sensitive to initial weights and a learning rate, and have a faster convergence rate than conventional neural networks. We can estimate nonlinear models in realtime by the proposed networks and control nonlinear models. To show the performance of this one, we control 7 degree simulation, this controller and driver were proved to be effective to drive a car in the environments of nonlinear road systems.

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