• Title/Summary/Keyword: Back Propagation

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Short-term Load Forecasting Using Artificial Neural Network (인공신경망을 이용한 단기 부하예측모형)

  • Park, Moon-Hee
    • Journal of Energy Engineering
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    • v.6 no.1
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    • pp.68-76
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    • 1997
  • This paper presents a new neural network training algorithm which reduces the required training time considerably and overcomes many of the shortcomings presented by the conventional back-propagation algorithm. The algorithm uses a modified form of the back-propagation algorithm to minimize the mean squared error between the desired and actual outputs with respect to the inputs to the nonlinearities. Artificial Neural Network (ANN) model using the new algorithm is applied to forecast the short-term electric load. Inputs to the ANN are past loads and the output of the ANN is the hourly load forecast for a given day.

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A Study on the Grinding Trouble-Shooting Utilizing the Neural Network (Neural Network을 응용한 연삭가공 트러블 인식.처리에 관한 연구)

  • 하만경;김건희;곽재삼;송지복;이재경;김희술
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.04b
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    • pp.113-117
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    • 1995
  • Grinding operations is accomplished by rotating a gfinding wheel with lots of random abrasive at high speed, and its object is generally obtained the fanal workpiece surface of high quality as well as the maximization of workpiece removal rate. But, especiallysince grinding operations is related with a large amount of functional parameter, it is actually difficult to therapy that the grinding trouble occurs during the grinding process. Therefore, we trytodesign grinding trouble-shooting system utilizing the back-propagation model of neural network. The conceptual method is produced byidentifying the four parameters derived from the grinding power, and we are design te to the grinding trouble-shooting system on the basis of their data. In this paper, cognition and therapy method tothe grinding trouble which utilizes neural network based four identified models are suggested, and implementation results of computer simulation with respect to the grinding burn and chatter vibration is presented.

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Detection of Grinding Troubles Utilizing a Neural Network (Neural Network을 이용한 연삭가공의 트러블 검지)

  • 곽재섭;송지복;김건희;하만경;김희술;이재경
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1994.10a
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    • pp.131-137
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    • 1994
  • Detection of grinding trouble occuring during the grinding process is classified into two types, i.e, based on the quantitative and qualitative knowledge. But, since the grinding operation is especially related with a large amount of functional parameters, it is actually defficult to cope with the grinding troubles occuring during process. Therefore, grinding trouble-shooting has difficulty in satisfying the requirement from the user. To cope with the grinding troubles occuring during the process, the application of neural network is on effective way. In this study, we identify the four parameters derived from the AE(Acoustic Emission) signals and present the grinding trouble-shooting system utilizing a back-propagation model of the neural network.

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Development of a Supporting System for Nutrient Solution Management in Hydroponics - II. Estimation of Electrical Conductivity(EC) using Neural Networks (양액재배를 위한 배양액관리 지원시스템의 개발 - II. 신경회로망에 의한 전기전도도(EC)의 추정)

  • 손정익;김문기;남상운
    • Journal of Bio-Environment Control
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    • v.1 no.2
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    • pp.162-168
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    • 1992
  • As the automation of nutrient solution management proceeds in the field of hydroponics, effective supporting systems to manage the nutrient solution by computer become needed. This study was attempt to predict the EC of nutrient solution using the neural networks. The multilayer perceptron consisting of 3 layers with the back propagation learning algorithm was selected for EC prediction, of which nine variables in the input layer were the concentrations of each ion and one variable in the output layer the EC of nutrient solution. The meq unit in ion concentration was selected fir input variable in the input layer. After the 10,000 learning sweeps with 108 sample data, the comparison of predicted and measured ECs for 72 test data showed good agreements with the correlation coefficient of 0.998. In addition, the predicted ECs by neural network showed relatively equal or closer to the measured ones than those by current complicated models.

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On-Line Fault Diagnosis System using Neural Network (신경망을 이용한 실시간 고장 진단 시스템)

  • 김문성;유승선;소정훈;곽훈성
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.11C
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    • pp.75-84
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    • 2001
  • In this paper, we propose an on-line FDD(Fault Detection and Diagnosis) system based on the three layer feed-forward neural network which is trained by the back-propagation teaming algorithm. We implement the on-line fault detection and diagnosis system by Visual C++ and Visual Basic. The proposed FDD system is applied to an air handling unit in operation. Experimental results show the high performance of our system in the task of fault detection and diagnosis.

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Real-Time Control of DC Sevo Motor with Variable Load Using PID-Learning Controller (PID 학습제어기를 이용한 가변부하 직류서보전동기의 실시간 제어)

  • Kim, Sang-Hoon;Chung, In-Suk;Kang, Young-Ho;Nam, Moon-Hyon;Kim, Lark-Kyo
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.50 no.3
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    • pp.107-113
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    • 2001
  • This paper deals with speed control of DC servo motor using a PID controller with a gain tuning based on a Back-Propagation(BP) Learning Algorithm. Conventionally a PID controller has been used in the industrial control. But a PID controller should produce suitable parameters for each system. Also, variables of the PID controller should be changed according to environments, disturbances and loads. In this paper described by a experiment that contained a method using a PID controller with a gain tuning based on a Back-Propagation(BP) Learning Algorithm, we developed speed characteristics of a DC servo motor on variable loads. The parameters of the controller are determined by neural network performed on on-line system after training the neural network on off-line system.

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Face Recognition Using Knowledge-Based Feature Extraction and Back-Propagation Algorithm (지식에 기초한 특정추출과 역전파 알고리즘에 의한 얼굴인식)

  • 이상영;함영국;박래홍
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.7
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    • pp.119-128
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    • 1994
  • In this paper, we propose a method for facial feature extraction and recognition algorithm using neural networks. First we extract a face part from the background image based on the knowledge that it is located in the center of an input image and that the background is homogeneous. Then using vertical and horizontal projections. We extract features from the separated face image using knowledge base of human faces. In the recognition step we use the back propagation algorithm of the neural networks and in the learning step to reduce the computation time we vary learning and momentum rates. Our technique recognizes 6 women and 14 men correctly.

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Speech Recognition of Multi-Syllable Words Using Soft Computing Techniques (소프트컴퓨팅 기법을 이용한 다음절 단어의 음성인식)

  • Lee, Jong-Soo;Yoon, Ji-Won
    • Transactions of the Society of Information Storage Systems
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    • v.6 no.1
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    • pp.18-24
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    • 2010
  • The performance of the speech recognition mainly depends on uncertain factors such as speaker's conditions and environmental effects. The present study deals with the speech recognition of a number of multi-syllable isolated Korean words using soft computing techniques such as back-propagation neural network, fuzzy inference system, and fuzzy neural network. Feature patterns for the speech recognition are analyzed with 12th order thirty frames that are normalized by the linear predictive coding and Cepstrums. Using four models of speech recognizer, actual experiments for both single-speakers and multiple-speakers are conducted. Through this study, the recognizers of combined fuzzy logic and back-propagation neural network and fuzzy neural network show the better performance in identifying the speech recognition.

Stencil cutting process by Nd:YAG laser- (I) Estimation of kerf width by neural network (Nd:YAG 레이저를 이용한 스텐실 절단공정- (I) 신경회로망에 의한 절단폭 예측)

  • 신동식;이제훈;한유희;이영문
    • Laser Solutions
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    • v.3 no.3
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    • pp.13-19
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    • 2000
  • The stencil is a thin stainless sheet in which a pattern is formed, which is placed on a surface of plate to reproduce the pattern of electric circuit. Conventionally the stencil has been produced by etching process. This process has many anti-environmental factors. In this study, Nd : YAG laser cutting process has been applied for stencil manufacturing. The study is focused on estimating kerf width of laser cut stencil by E.B.P.(Error Back-Propagation). This algorithm is good for estimating target value from input value. In this paper, target value was kerf width, and input values were frequency, pulse width, cutting speed and laser power. E.B.P. after teaming input and target could estimate kerf width from some variables precisely.

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Improvement of an Early Failure Rate By Using Neural Control Chart

  • Jang, K.Y.;Sung, C.J.;Lim, I.S.
    • International Journal of Reliability and Applications
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    • v.10 no.1
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    • pp.1-15
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    • 2009
  • Even though the impact of manufacturing quality to reliability is not considered much as well as that of design area, a major cause of an early failure of the product is known as manufacturing problem. This research applies two different types of neural network algorithms, the Back propagation (BP) algorithm and Learning Vector Quantization (LVQ) algorithm, to identify and classify the nonrandom variation pattern on the control chart based on knowledge-based diagnosis of dimensional variation. The performance and efficiency of both algorithms are evaluated to choose the better pattern recognition system for auto body assembly process. To analyze hundred percent of the data obtained by Optical Coordinate Measurement Machine (OCMM), this research considers an application in which individual observations rather than subsample means are used. A case study for analysis of OCMM data in underbody assembly process is presented to demonstrate the proposed knowledge-based pattern recognition system.

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