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

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Nonlinear mappings of interval vectors by neural networks (신경회로망에 의한 구간 벡터의 비선형 사상)

  • 권기택;배철수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.8
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    • pp.2119-2132
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    • 1996
  • This paper proposes four approaches for approximately realizing nonlinear mappling of interval vectors by neural networks. In the proposed approaches, training data for the learning of neural networks are the paris of interval input vectors and interval target output vectors. The first approach is a direct application of the standard BP (Back-Propagation) algorithm with a pre-processed training data. The second approach is an application of the two BP algorithms. The third approach is an extension of the BP algorithm to the case of interval input-output data. The last approach is an extension of the third approach to neural network with interval weights and interval biases. These approaches are compared with one another by computer simulations.

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A Neural Network Aided Kalman Filtering Approach for SINS/RDSS Integrated Navigation

  • Xiao-Feng, He;Xiao-Ping, Hu;Liang-Qing, Lu;Kang-Hua, Tang
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.491-494
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    • 2006
  • Kalman filtering (KF) is hard to be applied to the SINS (Strap-down Inertial Navigation System)/RDSS (Radio Determination Satellite Service) integrated navigation system directly because the time delay of RDSS positioning in active mode is random. BP (Back-Propagation) Neuron computing as a powerful technology of Artificial Neural Network (ANN), is appropriate to solve nonlinear problems such as the random time delay of RDSS without prior knowledge about the mathematical process involved. The new algorithm betakes a BP neural network (BPNN) and velocity feedback to aid KF in order to overcome the time delay of RDSS positioning. Once the BP neural network was trained and converged, the new approach will work well for SINS/RDSS integrated navigation. Dynamic vehicle experiments were performed to evaluate the performance of the system. The experiment results demonstrate that the horizontal positioning accuracy of the new approach is 40.62 m (1 ${\sigma}$), which is better than velocity-feedback-based KF. The experimental results also show that the horizontal positioning error of the navigation system is almost linear to the positioning interval of RDSS within 5 minutes. The approach and its anti-jamming analysis will be helpful to the applications of SINS/RDSS integrated systems.

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A Study on the Forecasting of Daily Streamflow using the Multilayer Neural Networks Model (다층신경망모형에 의한 일 유출량의 예측에 관한 연구)

  • Kim, Seong-Won
    • Journal of Korea Water Resources Association
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    • v.33 no.5
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    • pp.537-550
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    • 2000
  • In this study, Neural Networks models were used to forecast daily streamflow at Jindong station of the Nakdong River basin. Neural Networks models consist of CASE 1(5-5-1) and CASE 2(5-5-5-1). The criteria which separates two models is the number of hidden layers. Each model has Fletcher-Reeves Conjugate Gradient BackPropagation(FR-CGBP) and Scaled Conjugate Gradient BackPropagation(SCGBP) algorithms, which are better than original BackPropagation(BP) in convergence of global error and training tolerance. The data which are available for model training and validation were composed of wet, average, dry, wet+average, wet+dry, average+dry and wet+average+dry year respectively. During model training, the optimal connection weights and biases were determined using each data set and the daily streamflow was calculated at the same time. Except for wet+dry year, the results of training were good conditions by statistical analysis of forecast errors. And, model validation was carried out using the connection weights and biases which were calculated from model training. The results of validation were satisfactory like those of training. Daily streamflow forecasting using Neural Networks models were compared with those forecasted by Multiple Regression Analysis Mode(MRAM). Neural Networks models were displayed slightly better results than MRAM in this study. Thus, Neural Networks models have much advantage to provide a more sysmatic approach, reduce model parameters, and shorten the time spent in the model development.

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Kindergarten space design based on BP (back propagation) neural network (BP 신경 망 기반 유치원 공간 설계)

  • Liao, PengCheng;Pan, Younghwan
    • Journal of the Korea Convergence Society
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    • v.12 no.9
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    • pp.1-10
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    • 2021
  • In the past, designers relied primarily on past experience and reference to industry standard thresholds to design spaces. Such design often results in spaces that do not meet the needs of users. The purpose of this paper is to investigate the process and way of generating design parameters by constructing a BP neural network algorithm for spatial design. From the perspective. This paper adopts an experimental research method to take a kindergarten with a large number of complex needs in space as the object of study, and through the BP neural network algorithm in machine learning, the correlation between environmental behavior parameters and spatial design parameters is imprinted. The way of generating spatial design parameters is studied. In the future, the corresponding spatial design parameters can be derived by replacing specific environmental behavior influence factors, which can be applied to a wider range of scenarios and improve the efficiency of designers.

A Study on the Partial Discharge Pattern Recognition by Use of SOM Algorithm (SOM 알고리즘을 이용한 부분방전 패턴인식에 대한 연구)

  • Kim Jeong-Tae;Lee Ho-Keun;Lim Yoon Seok;Kim Ji-Hong;Koo Ja-Yoon
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.53 no.10
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    • pp.515-522
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    • 2004
  • In this study, we tried to investigate that the advantages of SOM(Self Organizing Map) algorithm such as data accumulation ability and the degradation trend trace ability would be adaptable to the analysis of partial discharge pattern recognition. For the purpose, we analyzed partial discharge data obtained from the typical artificial defects in GIS and XLPE power cable system through SOM algorithm. As a result, partial discharge pattern recognition could be well carried out with an acceptable error by use of Kohonen map in SOM algorithm. Also, it was clarified that the additional data could be accumulated during the operation of the algorithm. Especially, we found out that the data accumulation ability of Kohonen map could make it possible to suggest new patterns, which is impossible through the conventional BP(Back Propagation) algorithm. In addition, it is confirmed that the degradation trend could be easily traced in accordance with the degradation process. Therefore, it is expected to improve on-site applicability and to trace real-time degradation trends using SOM algorithm in the partial discharge pattern recognition

Pattern Recognition using Robust Feedforward Neural Networks (로버스트 다층전방향 신경망을 이용한 패턴인식)

  • Hwang, Chang-Ha;Kim, Sang-Min
    • Journal of the Korean Data and Information Science Society
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    • v.9 no.2
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    • pp.345-355
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    • 1998
  • The back propagation(BP) algorithm allows multilayer feedforward neural networks to learn input-output mappings from training samples. It iteratively adjusts the network parameters(weights) to minimize the sum of squared approximation errors using a gradient descent technique. However, the mapping acquired through the BP algorithm may be corrupt when errorneous training data are employed. In this paper two types of robust backpropagation algorithms are discussed both from a theoretical point of view and in the case studies of nonlinear regression function estimation and handwritten Korean character recognition. For future research we suggest Bayesian learning approach to neural networks and compare it with two robust backpropagation algorithms.

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A Study on the Stability of Neural Network Control Systems (신경망 제어 시스템의 안정도에 관한 연구)

  • Kim, Eun-Tai;Lee Hee-Jin;Kim Seung-Woo;Park Mi-Gnon
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.37 no.1
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    • pp.21-31
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    • 2000
  • In this paper, an analysis of the stability for a class of discrete-time neural network control systems is presentd. Based on Lyapunov's direct method, a sufficient stability condition for the neural network control systems is systematically derived and the modified back propagation algorithm which reflects the derived stability condition is suggested. The modified BP originates from the derived sufficient condition and guarantees the exponential stability of the resulting trained closed system. Finally, computer simulation is included to show an example where the derived stability condition and the BP modified bythe condition is used to train the control plant.

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A Study on the Reliability Improvement of Partial Discharge Pattern Recognition using Neural Network Combination (NNC) Method (Neural Network Combination (NNC) 기법을 이용한 부분방전 패턴인식의 신뢰성 향상에 관한 연구)

  • Kim, Seong-Il;Jeong, Seung-Yong;Koo, Ja-Yoon;Lim, Yun-Sok;Koo, Sun-Geun
    • Proceedings of the KIEE Conference
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    • 2005.11a
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    • pp.9-11
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    • 2005
  • 본 연구는 GIS 진단신뢰성 향상기술 개발을 목적으로, 16개의 인위적 결함을 이용하여 부분방전 신호를 발생시키고 검출하여 그 패턴인식 확률을 높이기 위하여 신경망에 Genetic Algorithm (GA) 을 적용하였다. 이를 위하여 다음과 같은 5가지 서로 다른 신경망 모델을 선택하였다: Back Propagation (BP), Jordan-Elman Network (JEN), Principal Component Analysis (PCA), Self-Organizing Feature Map (SOFM) 및 Support Vector Machine (SVM). 이와 같이 선택된 모델에 동일한 데이터를 학습 시키고 패턴인식 확률을 비교 및 분석하였다. 실험 결과에 의하면, BP의 인식률이 가장 높고 다음으로 JEN의 인식률이 높이 나타났으며, 후자의 경우 모든 결함에 대하여 정확한 패턴분류를 한 반면에 전자의 경우 1.8% 의 분류 오차가 발생하였다. 따라서 인식률이 높은 신경망이 더 정확한 패턴분류를 보장하지 못한다는 실험적 결과를 고려 할 때, 인식률이 높은 두 개의 모델을 선정하여 각각의 출력에 일정한 가중치를 주고 합산하여 새로운 출력을 얻는 방법을 제안한다.

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The study to measure of the BTX concentration using ANN (인공신경망을 이용한 BTX 농도 측정에 관한 연구)

  • 정영창;김동진;홍철호;이장훈;권혁구
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.5 no.1
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    • pp.1-6
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    • 2004
  • Air qualify monitoring if a primary activity for industrial and social environment. Especially, the VOCs(Volatile Organic Compounds) are very harmful for human and environment. Throughout this research. we designed sensor array with various kinds of gas sensor, and the recognition algorithm with ANN(Artificial Neural Network : BP), respectively. We have designed system to recognize various kinds and quantities of VOCs, such as benzene, tolylene, and xylene.

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A Study on Partial Discharge Pattern Recognition Using Neuro-Fuzzy Techniques (Neuro-Fuzzy 기법을 이용한 부분방전 패턴인식에 대한 연구)

  • Park, Keon-Jun;Kim, Gil-Sung;Oh, Sung-Kwun;Choi, Won;Kim, Jeong-Tae
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.12
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    • pp.2313-2321
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    • 2008
  • In order to develop reliable on-site partial discharge(PD) pattern recognition algorithm, the fuzzy neural network based on fuzzy set(FNN) and the polynomial network pattern classifier based on fuzzy Inference(PNC) were investigated and designed. Using PD data measured from laboratory defect models, these algorithms were learned and tested. Considering on-site situation where it is not easy to obtain voltage phases in PRPDA(Phase Resolved Partial Discharge Analysis), the measured PD data were artificially changed with shifted voltage phases for the test of the proposed algorithms. As input vectors of the algorithms, PRPD data themselves were adopted instead of using statistical parameters such as skewness and kurtotis, to improve uncertainty of statistical parameters, even though the number of input vectors were considerably increased. Also, results of the proposed neuro-fuzzy algorithms were compared with that of conventional BP-NN(Back Propagation Neural Networks) algorithm using the same data. The FNN and PNC algorithms proposed in this study were appeared to have better performance than BP-NN algorithm.