• 제목/요약/키워드: back propagation algorithm

검색결과 896건 처리시간 0.026초

신경망을 이용한 선박용 자동조타장치의 제어시스템 설계 (I) (Design of Neural-Network Based Autopilot Control System (I))

  • 곽문규;서상현
    • 대한조선학회논문집
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    • 제34권2호
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    • pp.56-63
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    • 1997
  • 본 논문에서는 신경망을 이용한 자동조타장치의 개발에 관한 연구결과를 소개한다. 본 연구에서는 먼저 신경망이론에 사용되는 대표적인 방법인 Back-Propagation 알고리즘의 원리를 설명하고 이를 이용하여 선박의 조종모델을 신경망으로 재구성하는 방법을 제시하였다. 신경망이론을 사용하여 선박운동모델을 System Identification 하는 경우의 문제점을 간단한 조종모델을 이용하여 수치적으로 검증하고 보다 복잡한 모델로 적용하는 경우에 대한 토의를 하였다. 본 논문에서 개발된 신경망이론들은 비선형성을 내포하고 있는 선박운동을 재구성하는데 효과적으로 사용될 수 있을 것으로 기대된다.

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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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    • 제28권2호
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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.

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

  • 차보남
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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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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양액재배를 위한 배양액관리 지원시스템의 개발 - II. 신경회로망에 의한 전기전도도(EC)의 추정 (Development of a Supporting System for Nutrient Solution Management in Hydroponics - II. Estimation of Electrical Conductivity(EC) using Neural Networks)

  • 손정익;김문기;남상운
    • 생물환경조절학회지
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    • 제1권2호
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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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신경망을 이용한 실시간 고장 진단 시스템 (On-Line Fault Diagnosis System using Neural Network)

  • 김문성;유승선;소정훈;곽훈성
    • 한국통신학회논문지
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    • 제26권11C호
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    • pp.75-84
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    • 2001
  • 본 논문에서는 신경망을 이용한 실시간 고장 검출 및 진단(FDD : Fault Detection and Diagnosis) 시스템을 제안한다. 제안된 시스템은 공조 시스템(FDD : Air Handling Unit)에서 발생 가능한 여러 고장들을 검출하고 진단할 수 있다. 고장 검출 및 진단 기법으로 3층 구조의 전방향(feed-forward) 신경망을 사용하였고, 여기에 사용된 학습 방법은 역전파(back-propagation) 학습 알고리즘이다. 공조 시스템에 적용된 실시간 고장 검출 및 진단 시스템은 비주얼 C++와 비주얼 베이직을 사용하여 구현하였다. 제안된 고장 검출 및 진단 시스템을 실제 운전 중인 공조 시스템에 적용하여 실험하였고, 정확한 고장 검출 및 진단이 수행됨을 실험 결과로서 입증하였다.

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

  • 이종수;윤지원
    • 정보저장시스템학회논문집
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    • 제6권1호
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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.

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

  • 신동식;이제훈;한유희;이영문
    • 한국레이저가공학회지
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    • 제3권3호
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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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A neural network model to assess the hysteretic energy demand in steel moment resisting frames

  • Akbas, Bulent
    • Structural Engineering and Mechanics
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    • 제23권2호
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    • pp.177-193
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    • 2006
  • Determining the hysteretic energy demand and dissipation capacity and level of damage of the structure to a predefined earthquake ground motion is a highly non-linear problem and is one of the questions involved in predicting the structure's response for low-performance levels (life safe, near collapse, collapse) in performance-based earthquake resistant design. Neural Network (NN) analysis offers an alternative approach for investigation of non-linear relationships in engineering problems. The results of NN yield a more realistic and accurate prediction. A NN model can help the engineer to predict the seismic performance of the structure and to design the structural elements, even when there is not adequate information at the early stages of the design process. The principal aim of this study is to develop and test multi-layered feedforward NNs trained with the back-propagation algorithm to model the non-linear relationship between the structural and ground motion parameters and the hysteretic energy demand in steel moment resisting frames. The approach adapted in this study was shown to be capable of providing accurate estimates of hysteretic energy demand by using the six design parameters.

Flashover Prediction of Polymeric Insulators Using PD Signal Time-Frequency Analysis and BPA Neural Network Technique

  • Narayanan, V. Jayaprakash;Karthik, B.;Chandrasekar, S.
    • Journal of Electrical Engineering and Technology
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    • 제9권4호
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    • pp.1375-1384
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    • 2014
  • Flashover of power transmission line insulators is a major threat to the reliable operation of power system. This paper deals with the flashover prediction of polymeric insulators used in power transmission line applications using the novel condition monitoring technique developed by PD signal time-frequency map and neural network technique. Laboratory experiments on polymeric insulators were carried out as per IEC 60507 under AC voltage, at different humidity and contamination levels using NaCl as a contaminant. Partial discharge signals were acquired using advanced ultra wide band detection system. Salient features from the Time-Frequency map and PRPD pattern at different pollution levels were extracted. The flashover prediction of polymeric insulators was automated using artificial neural network (ANN) with back propagation algorithm (BPA). From the results, it can be speculated that PD signal feature extraction along with back propagation classification is a well suited technique to predict flashover of polymeric insulators.

이동 무선 통신에서 신경망을 이용한 간섭 신호 제어 (Interference Signal Control using Neural Network in Digital Mobile Communication)

  • 나상동;배철수
    • 한국정보통신학회논문지
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    • 제2권1호
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    • pp.109-116
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    • 1998
  • 본 논문은 DS-SS 이동 통신 시스템에서 복합 다계층 퍼셉트론 신경망을 이용한 간섭 신호 제어로써 직접순차 확산 스펙트럼의 협대역 간섭 신호를 역전파 학습 알고리즘을 이용하여 억압하고, 컴퓨터 시뮬레이션을 통해 동일 채널 간섭과 협대역 간섭의 실제 톤(Tone)에서 빠른 수렴 비율과 더 좋은 성능을 가지는 복소수 역전파 알고리즘으로부터 제안된 새로운 복합 (CBPRLS)알고리즘은 기존의 RAKE 수신기보다 더 낮은 비트 에러 율을 가지는 NNAC(Neural Network Adaptive Correlator)를 통해 간섭 신호가 보다 효율적으로 제어됨을 분석 고찰한다.

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