• Title/Summary/Keyword: Back propagation

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A study on fatigue crack growth modelling by back propagation neural networks (역전파 신경회로망을 이용한 피로 균열성장 모델링에 관한 연구)

  • 주원식;조석수
    • Journal of Ocean Engineering and Technology
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    • v.10 no.1
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    • pp.65-74
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    • 1996
  • Up to now, the existing crack growth modelling has used a mathematical approximation but an assumed function have a great influence on this method. Especially, crack growth behavior that shows very strong nonlinearity needed complicated function which has difficulty in setting parameter of it. The main characteristics of neural network modelling to engineering field are simple calculations and absence of assumed function. In this paper, after discussing learning and generalization of neural networks, we performed crack growth modelling on the basis of above learning algorithms. J'-da/dt relation predicted by neural networks shows that test condition with unlearned data is simulated well within estimated mean error(5%).

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The Azimuth and Velocity Control of a Movile Robot with Two Drive Wheel by Neutral-Fuzzy Control Method (뉴럴-퍼지제어기법에 의한 두 구동휠을 갖는 이동 로봇의 자세 및 속도 제어)

  • 한성현
    • Journal of Ocean Engineering and Technology
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    • v.11 no.1
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    • pp.84-95
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    • 1997
  • This paper presents a new approach to the design speed and azimuth control of a mobile robot with drive wheel. The proposed control scheme uses a Gaussian function as a unit function in the fuzzy-neural network, and back propagation algorithm to train the fuzzy-neural network controller in the frmework of the specialized learning architecture. It is proposed a learning controller consisting of two neural network-fuzzy based on independent reasoning and a connection net with fixed weights to simple the neural networks-fuzzy. The performance of the proposed controller is shown by performing the computer simulation for trajectory tracking of the speed and azimuth of a mobile robot driven by two independent wheels.

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Improving Forecast Accuracy of Wind Speed Using Wavelet Transform and Neural Networks

  • Ramesh Babu, N.;Arulmozhivarman, P.
    • Journal of Electrical Engineering and Technology
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    • v.8 no.3
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    • pp.559-564
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    • 2013
  • In this paper a new hybrid forecast method composed of wavelet transform and neural network is proposed to forecast the wind speed more accurately. In the field of wind energy research, accurate forecast of wind speed is a challenging task. This will influence the power system scheduling and the dynamic control of wind turbine. The wind data used here is measured at 15 minute time intervals. The performance is evaluated based on the metrics, namely, mean square error, mean absolute error, sum squared error of the proposed model and compared with the back propagation model. Simulation studies are carried out and it is reported that the proposed model outperforms the compared model based on the metrics used and conclusions were drawn appropriately.

A Study on the Neuro-Fuzzy Control and Its Application

  • So, Myung-Ok;Yoo, Heui-Han;Jin, Sun-Ho
    • Journal of Advanced Marine Engineering and Technology
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    • v.28 no.2
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    • pp.228-236
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    • 2004
  • In this paper. we present a neuro-fuzzy controller which unifies both fuzzy logic and multi-layered feed forward neural networks. Fuzzy logic provides a means for converting linguistic control knowledge into control actions. On the other hand. feed forward neural networks provide salient features. such as learning and parallelism. In the proposed neuro-fuzzy controller. the parameters of membership functions in the antecedent part of fuzzy inference rules are identified by using the error back propagation algorithm as a learning rule. while the coefficients of the linear combination of input variables in the consequent part are determined by using the least square estimation method. Finally. the effectiveness of the proposed controller is verified through computer simulation for an inverted pole system.

Using Neural Network Approach for Monitoring of Chatter Vibration in Turning Operations (신경망을 이용한 선삭가공 시 Chatter vibration의 감시)

  • 남용석
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2000.04a
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    • pp.28-33
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    • 2000
  • The monitoring of the chatter vibration is necessarily required to do automatic manufacturing system. To this study, we constructed a sensing system using tool dynamometer in order to the chatter vibration on cutting process. And a approach to a neural network using the feature of principal cutting force signals is proposed. with the error back propagation training process, the neural network memorized and classified the feature of principal cutting force signals. As a result, it is shown by neural network that the chatter vibration can be monitored effectively.

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Design and Performance Evaluation of a Neural Network based Adaptive Filter for Application of Digital Controller (디지털 제어기용 적응 신경망 필터의 설계 및 성능평가)

  • 김진선;신우철;홍준희
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2004.10a
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    • pp.345-351
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    • 2004
  • This Paper describes a nonlinear adaptive noise filter using neural network for digital controller system. Back-Propagation Learning Algorithm based MLP (Multi Layer Perceptron)is used an adaptive filters. In this paper. it assume that the noise of primary input in the adaptive noise canceller is not the same characteristic as that of the reference input. Experimental reaults show that the neural network base noise canceller outperforms the linear noise canceller. Especially to make noise cancel close to realtime, Primary input is divided by unit and each divided part is processed for very short time than all the processed data are unified to whole data.

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Design of Real-Time Newral-Network Controller Based-on DSPs of a Assembling Robot (DSP를 이용한 조립용 로봇의 실시간 신경회로망 제어기 설계)

  • 차보남
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.10a
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    • pp.113-118
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    • 1999
  • This paper presents a new approach to the design of neural control system using digital signal processors in order to improve the precision and robustness. Robotic manipulators have become increasingly important n the field of flexible automation. High speed and high-precision trajectory tracking are indispensable capabilities for their versatile application. The need to meet demanding control requirement in increasingly complex dynamical control systems under significant uncertainties, leads toward design of intelligent manipulation robots. The TMS320C31 is used in implementing real time neural control to provide an enhanced motion control for robotic manipulators. In this control scheme, the networks introduced are neural nets with dynamic neurons, whose dynamics are distributed over all the network nodes. The nets are trained by the distributed dynamic back propagation algorithm. The proposed neural network control scheme is simple in structure, fast in computation, and suitable for implementation of real-time control. Performance of the neural controller is illustrated by simulation and experimental results for a SCARA robot.

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Development of a Neural-Fuzzy Control Algorithm for Dynamic Control of a Track Vehicle (궤도차량의 동적 제어를 위한 퍼지-뉴런 제어 알고리즘 개발)

  • 서운학
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.10a
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    • pp.142-147
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    • 1999
  • This paper presents a new approach to the dynamic control technique for track vehicle system using neural network-fuzzy control method. The proposed control scheme uses a Gaussian function as a unit function in the neural network-fuzzy, and back propagation algorithm to train the fuzzy-neural network controller in the framework of the specialized learning architecture. It is proposed a learning controller consisting of two neural network-fuzzy based on independent reasoning and a connection net with fixed weights to simply the neural networks-fuzzy. The performance of the proposed controller is shown by simulation for trajectory tracking of the speed and azimuth of a track vehicle.

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Role of Artificial Neural Networks in Multidisciplinary Optimization and Axiomatic Design

  • Lee, Jong-Soo
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.695-700
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    • 2008
  • Artificial neural network (ANN) has been extensively used in areas of nonlinear system modeling, analysis and design applications. Basically, ANN has its distinct capabilities of implementing system identification and/or function approximation using a number of input/output patterns that can be obtained via numerical and/or experimental manners. The paper describes a role of ANN, especially a back-propagation neural network (BPN) in the context of engineering analysis, design and optimization. Fundamental mechanism of BPN is briefly summarized in terms of training procedure and function approximation. The BPN based causality analysis (CA) is further discussed to realize the problem decomposition in the context of multidisciplinary design optimization. Such CA is also applied to quantitatively evaluate the uncoupled or decoupled design matrix in the context of axiomatic design with the independence axiom.

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Recipe Prediction of Colorant Proportion for Target Color Reproduction (목표색상 재현을 위한 페인트 안료 배합비율의 예측)

  • Hwang, Kyu-Suk;Park, Chang-Won
    • Journal of the Korean Applied Science and Technology
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    • v.25 no.4
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    • pp.438-445
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    • 2008
  • For recipe prediction of colorant proportion showing nonlinear behavior, we modeled the effects of colorant proportion of basic colors on the target colors and predicted colorant proportion necessary for making target colors. First, colorant proportion of basic colors and color information indicated by the instrument was applied by a linear model and a multi-layer perceptrons model with back-propagation learning method. However, satisfactory results were not obtained because of nonlinear property of colors. Thus, in this study the neuro-fuzzy model with merit of artificial neural networks and fuzzy systems was presented. The proposed model was trained with test data and colorant proportion was predicted. The effectiveness of the proposed model was verified by evaluation of color difference(${\Delta}E$).