• Title/Summary/Keyword: back propagation (BP)

Search Result 154, Processing Time 0.026 seconds

Optimal Process Parameters for Achieving the Desired Top-Bead Width in GMA welding Process (GMA 용접의 윗면 비드폭 선정을 위한 최적 공정변수들)

  • ;Prasad
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.11 no.4
    • /
    • pp.89-96
    • /
    • 2002
  • This paper aims to develop an intelligent model for predicting top-bead width for the robotic GMA(Gas Metal Arc) welding process using BP(Back-propagation) neural network and multiple regression analysis. Firstly, based on experimental data, the basic factors affecting top-bead width are identified. Then BP neural network model and multiple regression models of top-bead width are established. The modeling methods and procedure are explained. The developed models are then verified by data obtained from the additional experiment and the predictive behaviors of the two kind of models are compared and analysed. Finally the modeling methods, predictive behaviors md the advantages of each models are discussed.

LM-BP algorithm application for odour classification and concentration prediction using MOS sensor array (MOS 센서어레이를 이용한 냄새 분류 및 농도추정을 위한 LM-BP 알고리즘 응용)

  • 최찬석;변형기;김정도
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2000.10a
    • /
    • pp.210-210
    • /
    • 2000
  • In this paper, we have investigated the properties of multi-layer perceptron (MLP) for odour patterns classification and concentration estimation simultaneously. When the MLP may be has a fast convergence speed with small error and excellent mapping ability for classification, it can be possible to use for classification and concentration prediction of volatile chemicals simultaneously. However, the conventional MLP, which is back-Propagation of error based on the steepest descent method, was difficult to use for odour classification and concentration estimation simultaneously, because it is slow to converge and may fall into the local minimum. We adapted the Levenberg-Marquardt(LM) algorithm [4,5] having advantages both the steepest descent method and Gauss-Newton method instead of the conventional steepest descent method for the simultaneous classification and concentration estimation of odours. And, We designed the artificial odour sensing system(Electronic Nose) and applied LM-BP algorithm for classification and concentration prediction of VOC gases.

  • PDF

A Dynamically Reconfiguring Backpropagation Neural Network and Its Application to the Inverse Kinematic Solution of Robot Manipulators (동적 변화구조의 역전달 신경회로와 로보트의 역 기구학 해구현에의 응용)

  • 오세영;송재명
    • The Transactions of the Korean Institute of Electrical Engineers
    • /
    • v.39 no.9
    • /
    • pp.985-996
    • /
    • 1990
  • An inverse kinematic solution of a robot manipulator using multilayer perceptrons is proposed. Neural networks allow the solution of some complex nonlinear equations such as the inverse kinematics of a robot manipulator without the need for its model. However, the back-propagation (BP) learning rule for multilayer perceptrons has the major limitation of being too slow in learning to be practical. In this paper, a new algorithm named Dynamically Reconfiguring BP is proposed to improve its learning speed. It uses a modified version of Kohonen's Self-Organizing Feature Map (SOFM) to partition the input space and for each input point, select a subset of the hidden processing elements or neurons. A subset of the original network results from these selected neuron which learns the desired mapping for this small input region. It is this selective property that accelerates convergence as well as enhances resolution. This network was used to learn the parity function and further, to solve the inverse kinematic problem of a robot manipulator. The results demonstrate faster learning than the BP network.

Comparative Analysis of BP and SOM for Partial Discharge Pattern Recognition (부분방전 패턴인식에 대한 BP 및 SOM 알고리즘 비교 분석)

  • Lee, Ho-Keun;Kim, Jeong-Tae;Lim, Yoon-Seok;Kim, Ji-Hong;Koo, Ja-Yoon
    • Proceedings of the KIEE Conference
    • /
    • 2004.07c
    • /
    • pp.1930-1932
    • /
    • 2004
  • SOM(Self Organizing Map) algorithm which has some advantages such as data accumulation ability and the degradation trend trace ability was compared with conventionally used BP(Back Propagation) algorithm. For the purpose, partial discharge data were acquired and analysed from the artificial defects in GIS. As a result, basically the pattern recognition rate of BP algorithm was found out to be better than that of SOM algorithm. However, SOM algorithm showed a great on-site-applicability such as ability of suggesting new-pattern-possibility. Therefore, through increasing pattern recognition rate it is possible to apply SOM algorithm to partial discharge analysis. Also, for the image processing method it is required the normalization of the PRPDA graph. However, due to the normalization both BP and SOM algorithm have shown worse results, so that it is required further study to solve the problem.

  • PDF

A Neural Net System Self-organizing the Distributed Concepts for Speech Recognition (음성인식을 위한 분산개념을 자율조직하는 신경회로망시스템)

  • Kim, Sung-Suk;Lee, Tai-Ho
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.26 no.5
    • /
    • pp.85-91
    • /
    • 1989
  • In this paper, we propose a neural net system for speech recognition, which is composed of two neural networks. Firstly the self-supervised BP(Back Propagation) network generates the distributed concept corresponding to the activity pattern in the hidden units. And then the self-organizing neural network forms a concept map which directly displays the similarity relations between concepts. By doing the above, the difficulty in learning the conventional BP network is solved and the weak side of BP falling into a pattern matcher is gone, while the strong point of generating the various internal representations is used. And we have obtained the concept map which is more orderly than the Kohonen's SOFM. The proposed neural net system needs not any special preprocessing and has a self-learning ability.

  • PDF

A Study on the Implementation of Hybrid Learning Rule for Neural Network (다층신경망에서 하이브리드 학습 규칙의 구현에 관한 연구)

  • Song, Do-Sun;Kim, Suk-Dong;Lee, Haing-Sei
    • The Journal of the Acoustical Society of Korea
    • /
    • v.13 no.4
    • /
    • pp.60-68
    • /
    • 1994
  • In this paper we propose a new Hybrid learning rule applied to multilayer feedforward neural networks, which is constructed by combining Hebbian learning rule that is a good feature extractor and Back-Propagation(BP) learning rule that is an excellent classifier. Unlike the BP rule used in multi-layer perceptron(MLP), the proposed Hybrid learning rule is used for uptate of all connection weights except for output connection weigths becase the Hebbian learning in output layer does not guarantee learning convergence. To evaluate the performance, the proposed hybrid rule is applied to classifier problems in two dimensional space and shows better performance than the one applied only by the BP rule. In terms of learning speed the proposed rule converges faster than the conventional BP. For example, the learning of the proposed Hybrid can be done in 2/10 of the iterations that are required for BP, while the recognition rate of the proposed Hybrid is improved by about $0.778\%$ at the peak.

  • PDF

Speed Identification and Control of Induction Motor drives using Neural Network with Kalman Filter Approach (칼만필터 신경회로망을 이용한 유도전동기의 속도 추정과 제어)

  • 김윤호;최원범;국윤상
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.4 no.2
    • /
    • pp.184-191
    • /
    • 1999
  • 일반적으로 시스템 인식과 제어를 위해 이용하는 다층망 신경회로망은 기존의 역전파알고리즘을 이용한다. 그러나 결선강도에 대한 오차의 기울기를 구하는 방법이기 때문에 국부적 최소점에 빠지기 쉽고, 수렴속도가 매우 늦으며 초기결선강도 값들이나 학습계수에 민감하게 반응한다. 이와 같은 단점을 개선하기 위해 본 논문에서는 칼만필터링 기법을 도입하여 수렴속도를 빠르게 하고 초기 결선강도의 영향을 받지 않도록 개선하였으며, 유도전동기의 속도추정과 제어에 적용하여 좋은 결과를 보였다.

  • PDF

Automatic Detection of Interstitial Lung Disease using Neural Network

  • Kouda, Takaharu;Kondo, Hiroshi
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.2 no.1
    • /
    • pp.15-19
    • /
    • 2002
  • Automatic detection of interstitial lung disease using Neural Network is presented. The rounded opacities in the pneumoconiosis X-ray photo are picked up quickly by a back propagation (BP) neural network with several typical training patterns. The training patterns from 0.6 mm ${\O}$ to 4.0 mm ${\O}$ are made by simple circles. The total evaluation is done from the size and figure categorization. Mary simulation examples show that the proposed method gives much reliable result than traditional ones.

A NEW LEARNING ALGORITHM FOR DRIVING A MOBILE VEHICLE

  • Sugisaka, Masanori;Wang, Xin
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1998.10a
    • /
    • pp.173-178
    • /
    • 1998
  • The strategy presented in this paper is based on modifying the past patterens and adjusting the content of the driving patterns by a new algorithm. Learning happens during the driving procedure of a mobile vehicle. The purpose of this paper is to solve the problem how to realize the hardware neurocomputer by back propagation (BP) neural network learning on-line.

  • PDF

Iris Lesion recognition System using Higher Order Local Autocorrelation Features and Back-propagation (HLAF 특징과 신경망을 이용한 홍채 병변 인식 시스템)

  • Jeong, Yu-Jeong;Jung, Chai-Yeoung
    • Annual Conference of KIPS
    • /
    • 2002.11a
    • /
    • pp.723-726
    • /
    • 2002
  • 기존의 화상처리 방법으로는 불필요한 정보까지 포함하여 특징을 추출하여 많은 시간이 소용된다는 문제점이 있었다. 본 논문에서 적합한 HLAF 알고리즘를 이용하여 홍채 병변 인식의 수렴속도를 빠르게 하는 신경망을 사용하였으며, HLAF 알고리즘이 일반 BP 알고리즘보다 수렴속도면과 병변 추출 인식면에서 훨씬 우수함을 보였다.

  • PDF