• 제목/요약/키워드: RBF Network

검색결과 242건 처리시간 0.033초

Artificial neural network reconstructs core power distribution

  • Li, Wenhuai;Ding, Peng;Xia, Wenqing;Chen, Shu;Yu, Fengwan;Duan, Chengjie;Cui, Dawei;Chen, Chen
    • Nuclear Engineering and Technology
    • /
    • 제54권2호
    • /
    • pp.617-626
    • /
    • 2022
  • To effectively monitor the variety of distributions of neutron flux, fuel power or temperatures in the reactor core, usually the ex-core and in-core neutron detectors are employed. The thermocouples for temperature measurement are installed in the coolant inlet or outlet of the respective fuel assemblies. It is necessary to reconstruct the measurement information of the whole reactor position. However, the reading of different types of detector in the core reflects different aspects of the 3D power distribution. The feasibility of reconstruction the core three-dimension power distribution by using different combinations of in-core, ex-core and thermocouples detectors is analyzed in this paper to synthesize the useful information of various detectors. A comparison of multilayer perceptron (MLP) network and radial basis function (RBF) network is performed. RBF results are more extreme precision but also more sensitivity to detector failure and uncertainty, compare to MLP networks. This is because that localized neural network could offer conservative regression in RBF. Adding random disturbance in training dataset is helpful to reduce the influence of detector failure and uncertainty. Some convolution neural networks seem to be helpful to get more accurate results by use more spatial layout information, though relative researches are still under way.

An Identification Technique Based on Adaptive Radial Basis Function Network for an Electronic Odor Sensing System

  • Byun, Hyung-Gi
    • 센서학회지
    • /
    • 제20권3호
    • /
    • pp.151-155
    • /
    • 2011
  • A variety of pattern recognition algorithms including neural networks may be applicable to the identification of odors. In this paper, an identification technique for an electronic odor sensing system applicable to wound state monitoring is presented. The performance of the radial basis function(RBF) network is highly dependent on the choice of centers and widths in basis function. For the fine tuning of centers and widths, those parameters are initialized by an ill-conditioned genetic fuzzy c-means algorithm, and the distribution of input patterns in the very first stage, the stochastic gradient(SG), is adapted. The adaptive RBF network with singular value decomposition(SVD), which provides additional adaptation capabilities to the RBF network, is used to process data from array-based gas sensors for early detection of wound infection in burn patients. The primary results indicate that infected patients can be distinguished from uninfected patients.

Radial Basis Function Neural Network for Power System Transient Energy Margin Estimation

  • Karami, Ali
    • Journal of Electrical Engineering and Technology
    • /
    • 제3권4호
    • /
    • pp.468-475
    • /
    • 2008
  • This paper presents a method for estimating the transient stability status of the power system using radial basis function(RBF) neural network with a fast hybrid training approach. A normalized transient energy margin(${\Delta}V_n$) has been obtained by the potential energy boundary surface(PEBS) method along with a time-domain simulation technique, and is used as an output of the RBF neural network. The RBF neural network is then trained to map the operating conditions of the power system to the ${\Delta}V_n$, which provides a measure of the transient stability of the power system. The proposed approach has been successfully applied to the 10-machine 39-bus New England test system, and the results are given.

신경망 기반의 오염부하량 산정을 위한 위성영상 토지피복 분류기법 (Neural Network Based Land Cover Classification Technique of Satellite Image for Pollutant Load Estimation)

  • Park, Sang-Young;Ha, Sung-Ryong
    • 한국지능시스템학회:학술대회논문집
    • /
    • 한국퍼지및지능시스템학회 2001년도 추계학술대회 학술발표 논문집
    • /
    • pp.1-4
    • /
    • 2001
  • Landsat TM 위성영상을 대상으로 인공신경망 모형과 RBF 신경망 모형의 토지피복분류 정확도를 평가하였다. 토지피복의 특성에 따라 세 개의 연구지역(복합토지이용, 농경지, 도시지역)을 대상으로 RBF 신경망 모형의 입력밴드 조합 및 분류 항목의 변화에 따른 민감도 분석이 수행되었다. 오염부하 원단위의 신뢰구간 및 분포를 추정하기 위하여 붓스트랩기법이 적화하였으며, 특히 토지이용이 다양한 도시지역에서 가장 큰 변화폭을 보였다.

  • PDF

퍼지 RBF 네트워크의 학습 성능 개선 (Learning Performance Improvement of Fuzzy RBF Network)

  • 김재용;김광백
    • 한국지능시스템학회:학술대회논문집
    • /
    • 한국퍼지및지능시스템학회 2005년도 춘계학술대회 학술발표 논문집 제15권 제1호
    • /
    • pp.335-339
    • /
    • 2005
  • 본 논문에서는 퍼지 RBF 네트워크의 학습 성능을 개선하기 위하여 Delta-bar-Delta 알고리즘을 적용하여 학습률을 동적으로 조정하는 개선된 퍼지 RBF 네트워크를 제안한다. 제안된 학습 알고리즘은 일반화된 델타 학습 방법에 퍼지 C-Means 알고리즘을 결합한 방법으로, 중간층의 노드를 자가 생성하고 중간층과 출력충의 학습에는 일반화된 델타 학습 방법에 Delta-bar-Delta 알고리즘을 적용하여 학습률을 동적으로 조정하여 학습 성능을 개선한다. 제안된 RBF 네트워크의 학습 성능을 평가하기 위하여 컨테이너 영상에서 추출한 40개의 식별자를 학습 데이터로 적용한 결과, 기존의 ART2 기반 RBF 네트워크와 기존의 퍼지 RBF 네트워크 보다 학습 시간이 적게 소요되고, 학습의 수렴성이 개선된 것을 확인하였다.

  • PDF

RBF/ART1을 이용한 선삭에서 절삭력을 이상신호 검출 (Fault Detection of Cutting Force in Turning Process using RBF/ART-1)

  • 임상만;이명재;유봉환
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 1994년도 추계학술대회 논문집
    • /
    • pp.15-19
    • /
    • 1994
  • The application of neural network for fault dection of cutting force in turning was introduced. This monitoring system consist of a RBF predicton model and a ART-1 pattern classifier. RBF prediction model predict a cutting force signal. Prediction error of predictor is used for a input vector of ART-1 pattern classifier. Prediction error could be successfully performed to fault signal monitoring of ART-1 pattern classifier.

  • PDF

Neural Network을 이용한 무선 통신시스템에서의 VAD (VAD By Neural Network Under Wireless Communication Systems)

  • 이호선;김수경;박승권
    • 한국통신학회논문지
    • /
    • 제30권12C호
    • /
    • pp.1262-1267
    • /
    • 2005
  • EBF(Elliptical basis function) 신경망은 비선형 처리를 가능하게 하며, 잡음에 강하고 빠른 수렴을 하는 장점이 있다. 또한 EBF는 설계가 간단하여 실시간 음성 구간 검출기(Voice Activity Detection, VAD)에 적용하기 용이하다. 따라서 전송 효율을 높이기 위해 사용되는 음성구간 검출기를 제안함에 있어 EBF 신경망을 이용하였다. EBF의 학습 알고리즘은 평균 클러스터링(K-means Clustering) 알고리즘과 선형 최소 제곱 방범(Least Mean Square error, LMS)을 사용하였다. G.729 Annex B 와 RBF(Radial Basis Function) 신경망을 이용한 음성구간 검출기와 성능 비교에 있에서, G.729 Annex B 음성 검출기보다 $70\%$ 이상의 높은 성능재선을 나타냈고, RBF 신경망을 이용한 음성구간 검출기 보다 비음성 구간에서 $50\%$정도의 높은 효율을 보였다.

APPLICATION OF NEURAL NETWORK FOR THE CLOUD DETECTION FROM GEOSTATIONARY SATELLITE DATA

  • Ahn, Hyun-Jeong;Ahn, Myung-Hwan;Chung, Chu-Yong
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
    • /
    • pp.34-37
    • /
    • 2005
  • An efficient and robust neural network-based scheme is introduced in this paper to perform automatic cloud detection. Unlike many existing cloud detection schemes which use thresholding and statistical methods, we used the artificial neural network methods, the multi-layer perceptrons (MLP) with back-propagation algorithm and radial basis function (RBF) networks for cloud detection from Geostationary satellite images. We have used a simple scene (a mixed scene containing only cloud and clear sky). The main results show that the neural networks are able to handle complex atmospheric and meteorological phenomena. The experimental results show that two methods performed well, obtaining a classification accuracy reaching over 90 percent. Moreover, the RBF model is the most effective method for the cloud classification.

  • PDF

Application of wavelet multiresolution analysis and artificial intelligence for generation of artificial earthquake accelerograms

  • Amiri, G. Ghodrati;Bagheri, A.
    • Structural Engineering and Mechanics
    • /
    • 제28권2호
    • /
    • pp.153-166
    • /
    • 2008
  • This paper suggests the use of wavelet multiresolution analysis (WMRA) and neural network for generation of artificial earthquake accelerograms from target spectrum. This procedure uses the learning capabilities of radial basis function (RBF) neural network to expand the knowledge of the inverse mapping from response spectrum to earthquake accelerogram. In the first step, WMRA is used to decompose earthquake accelerograms to several levels that each level covers a special range of frequencies, and then for every level a RBF neural network is trained to learn to relate the response spectrum to wavelet coefficients. Finally the generated accelerogram using inverse discrete wavelet transform is obtained. An example is presented to demonstrate the effectiveness of the method.

Face Recognition Based on Improved Fuzzy RBF Neural Network for Smar t Device

  • Lee, Eung-Joo
    • 한국멀티미디어학회논문지
    • /
    • 제16권11호
    • /
    • pp.1338-1347
    • /
    • 2013
  • Face recognition is a science of automatically identifying individuals based their unique facial features. In order to avoid overfitting and reduce the computational reduce the computational burden, a new face recognition algorithm using PCA-fisher linear discriminant (PCA-FLD) and fuzzy radial basis function neural network (RBFNN) is proposed in this paper. First, face features are extracted by the principal component analysis (PCA) method. Then, the extracted features are further processed by the Fisher's linear discriminant technique to acquire lower-dimensional discriminant patterns, the processed features will be considered as the input of the fuzzy RBFNN. As a widely applied algorithm in fuzzy RBF neural network, BP learning algorithm has the low rate of convergence, therefore, an improved learning algorithm based on Levenberg-Marquart (L-M) for fuzzy RBF neural network is introduced in this paper, which combined the Gradient Descent algorithm with the Gauss-Newton algorithm. Experimental results on the ORL face database demonstrate that the proposed algorithm has satisfactory performance and high recognition rate.