• 제목/요약/키워드: RBF Network

검색결과 242건 처리시간 0.024초

Partial Discharge Pattern Recognition of Cast Resin Current Transformers Using Radial Basis Function Neural Network

  • Chang, Wen-Yeau
    • Journal of Electrical Engineering and Technology
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    • 제9권1호
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    • pp.293-300
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    • 2014
  • This paper proposes a novel pattern recognition approach based on the radial basis function (RBF) neural network for identifying insulation defects of high-voltage electrical apparatus arising from partial discharge (PD). Pattern recognition of PD is used for identifying defects causing the PD, such as internal discharge, external discharge, corona, etc. This information is vital for estimating the harmfulness of the discharge in the insulation. Since an insulation defect, such as one resulting from PD, would have a corresponding particular pattern, pattern recognition of PD is significant means to discriminate insulation conditions of high-voltage electrical apparatus. To verify the proposed approach, experiments were conducted to demonstrate the field-test PD pattern recognition of cast resin current transformer (CRCT) models. These tests used artificial defects created in order to produce the common PD activities of CRCTs by using feature vectors of field-test PD patterns. The significant features are extracted by using nonlinear principal component analysis (NLPCA) method. The experimental data are found to be in close agreement with the recognized data. The test results show that the proposed approach is efficient and reliable.

현재 기상 정보의 이동 평균을 사용한 태양광 발전량 예측 (Use of the Moving Average of the Current Weather Data for the Solar Power Generation Amount Prediction)

  • 이현진
    • 한국멀티미디어학회논문지
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    • 제19권8호
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    • pp.1530-1537
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    • 2016
  • Recently, solar power generation shows the significant growth in the renewable energy field. Using the short-term prediction, it is possible to control the electric power demand and the power generation plan of the auxiliary device. However, a short-term prediction can be used when you know the weather forecast. If it is not possible to use the weather forecast information because of disconnection of network at the island and the mountains or for security reasons, the accuracy of prediction is not good. Therefore, in this paper, we proposed a system capable of short-term prediction of solar power generation amount by using only the weather information that has been collected by oneself. We used temperature, humidity and insolation as weather information. We have applied a moving average to each information because they had a characteristic of time series. It was composed of min, max and average of each information, differences of mutual information and gradient of it. An artificial neural network, SVM and RBF Network model was used for the prediction algorithm and they were combined by Ensemble method. The results of this suggest that using a moving average during pre-processing and ensemble prediction models will maximize prediction accuracy.

서베일런스에서 베이지안 분류기를 이용한 객체 검출 및 추적 (Object Detection and Tracking using Bayesian Classifier in Surveillance)

  • 강성관;최경호;정경용;이정현
    • 디지털융복합연구
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    • 제10권6호
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    • pp.297-302
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    • 2012
  • 본 논문은 이미지 상황분석을 기반으로 하여 객체 검출 및 추적 방법을 제안한다. 제안하는 방법은 배경이 복잡한 형태이거나 배경이 동적으로 움직일 때에도 일관성 있는 결과를 얻을 수 있다. 입력 영상의 상황분석은 K-means와 RBF의 하이브리드 네트워크를 이용하여 수행되어진다. 제안된 객체 검출은 일정하지 않은 객체 이미지 때문에 생기는 영향을 감소시키기 위해 상황 기반 적응적 베이지안 네트워크를 이용한다. 본 논문에서는 학습 속도를 높이기 위해 2D Haar 웨이블릿 변형을 이용한 특징 벡터 생성기와 베이지안 판별식 방법을 이용하여 학습 시간이 적게 걸리며 학습 데이터의 변화에 일정한 성능을 갖는 방법론을 제안하였다. 제안하는 방법을 개발하여 실환경에 적용한 결과 검출하고자 하는 물체가 예측 영역을 넘나들거나 다른 불확실한 변화에도 안정적으로 반응함을 알 수 있었다. 실험 결과는 기존의 방법들에서 사용되었던 다양한 데이터 집합에 적용하였을 때 우수한 성능을 보여준다.

적응적 특징추출을 이용한 Radial Basis Function 신경망의 성능개선 (Performance Improvement of Radial Basis Function Neural Networks Using Adaptive Feature Extraction)

  • 조용현
    • 한국멀티미디어학회논문지
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    • 제3권3호
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    • pp.253-262
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    • 2000
  • 본 논문에서는 적응적으로 추출된 입력 데이터의 특징을 은닉층 뉴런 개수와 중심값 설정에 이용하는 새로운 radial basis 함수 신경망을 제안하였다. 제안된 신경망에서는 입력데이터의 특징을 효과적으로 추출하기 위해 적응 학습알고리즘의 주요성분분석 기법을 이용하였다. 이렇게 하면 주요성분분석 기법이 가지는 대용량의 입력데이터를 통계적으로 독립인 특징들의 집합으로 변환시키는 장점과 RBF신경망이 가지는 우수한 속성을 그대로 살릴 수 있다. 제안된 기법의 radial basis 함수 신경망을 200명의 암환자를 2부류(초기와 악성)로 분류하는 문제에 적용하여 시뮬레이션한 결과, k-평균 군집화 알고리즘을 이용한 radial basis 함수 신경망에 의한 결과와 비교할 때 학습시간과 시험 데이터의 분류에서 더욱 우수한 성능이 있음을 확인할 수 있었다. 그리고 신경망의 초기 연 결가중치에 대한 의존도와 평활요소의 설정여유도 측면에서도 우수한 특성이 있음을 확인할 수 있었다.

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퍼지-ARTMAP에 의한 채널 등화 (Channel Equalization using Fuzzy-ARTMAP)

  • 이정식;한수환
    • 한국멀티미디어학회논문지
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    • 제4권4호
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    • pp.333-338
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    • 2001
  • 본 논문에서는 이전에 개발된 신경회로망 채널 등화기에서 볼 수 있었던 구조의 복잡성 및 많은 학습시간의 소요 등과 같은 단점을 극복하고자 퍼지-ARTMAP 신경망을 이용하여 채널 등화기를 구성하였다. 제안된 퍼지-ARTMAP 채널 등화기는 다른 형태의 신경망을 이용한 등화기에서는 찾아 볼 수 없는 빠르고 쉬운 학습 능력을 갖고 있다. 즉, 등화기 구성에 필요한 파라미터의 수가 적으며 지역적 최소값에 빠질 우려 없이 각 계층간의 초기 연결강도를 지정할 수 있을 뿐만 아니라 기존의 학습된 데이터를 재학습시킬 필요 없이 새로운 데이터를 단순히 추가 학습시킬 수 있는 장점 등을 가지고 있다. 본 연구의 시뮬레이션 과정에서는 선형채널에서 발생된 가우시안 잡음을 동반한 이진 신호를 대상으로 퍼지-ARTMAP 채널 등화기의 성능을 LMS 기반의 선형 등화기 및 MLP와 RBF 신경망 등화기와 비교하였으며 퍼지-ARTMAP 등화기가 상대적으로 간단한 구조와 빠른 처리속도를 가짐은 물론 선형등화기로 해결하지 못했던 비선형 문제들도 해결할 수 있음을 보였다.

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신경망모형을 이용한 외래환자 만족도예측 및 민감도분석 (A Neural Network for Prediction and Sensitivity of Outpatients' Satisfaction)

  • 이견직;정영철;김미라
    • 한국병원경영학회지
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    • 제8권1호
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    • pp.81-94
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    • 2003
  • This paper aims at developing a prediction model and analyzing a sensitivity for the outpatient's overall satisfaction on utilizing hospital services by using data mining techniques within the context of customer satisfaction. From a total of 900 outpatient cases, 80 percent were randomly selected as the training group and the other 20 percent as the validation group. Cases in the training group were used in the development of the CHAID and Neural Networks. The validation group was used to test the performance of these models. The major findings may be summarized as follows: the CHAID provided six useful predictors - satisfaction with treatment level, satisfaction with healthcare facilities and equipments, satisfaction with registration service, awareness of hospital reputation, satisfaction with staffs courtesy and responsiveness, and satisfaction with nurses kindness. The prediction accuracy rates based on MLP (77.90%) is superior to RBF (76.80%).

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하수처리 공정을 위한 Type-2 RBF Neural Networks 모델링 설계 (Design of Type-2 Radial Basis Function Neural Networks Modeling for Sewage Treatment Process)

  • 이승철;권학주;오성권
    • 전기학회논문지
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    • 제64권10호
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    • pp.1469-1478
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    • 2015
  • In this paper, The methodology of Type-2 fuzzy set-based Radial Basis Function Neural Network(T2RBFNN) is proposed for Sewage Treatment Process and the simulator is developed for application to the real-world sewage treatment plant by using the proposed model. The proposed model has robust characteristic than conventional RBFNN. architecture of network consist of three layers such as input layer, hidden layer and output layer of RBFNN, and Type-2 fuzzy set is applied to receptive field in contrast with conventional radial basis function. In addition, the connection weights of the proposed model are defined as linear polynomial function, and then are learned through Back-Propagation(BP). Type reduction is carried out by using Karnik and Mendel(KM) algorithm between hidden layer and output layer. Sewage treatment data obtained from real-world sewage treatment plant is employed to evaluate performance of the proposed model, and their results are analyzed as well as compared with those of conventional RBFNN.

A Novel Approach to Predict the Longevity in Alzheimer's Patients Based on Rate of Cognitive Deterioration using Fuzzy Logic Based Feature Extraction Algorithm

  • Sridevi, Mutyala;B.R., Arun Kumar
    • International Journal of Computer Science & Network Security
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    • 제21권8호
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    • pp.79-86
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    • 2021
  • Alzheimer's is a chronic progressive disease which exhibits varied symptoms and behavioural traits from person to person. The deterioration in cognitive abilities is more noticeable through their Activities and Instrumental Activities of Daily Living rather than biological markers. This information discussed in social media communities was collected and features were extracted by using the proposed fuzzy logic based algorithm to address the uncertainties and imprecision in the data reported. The data thus obtained is used to train machine learning models in order to predict the longevity of the patients. Models built on features extracted using the proposed algorithm performs better than models trained on full set of features. Important findings are discussed and Support Vector Regressor with RBF kernel is identified as the best performing model in predicting the longevity of Alzheimer's patients. The results would prove to be of high value for healthcare practitioners and palliative care providers to design interventions that can alleviate the trauma faced by patients and caregivers due to chronic diseases.

FCM에 기반한 자가생성 지도학습알고리즘을 이용한 전력선의 고장전류 판별 (Fault Current Discrimination of Power Line using FCM allowing self-organization)

  • 정종원;원태현;이준탁
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2011년도 제42회 하계학술대회
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    • pp.368-369
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    • 2011
  • This article suggests an online-based remote fault current mode discrimination method in order to identify the causes of the power line faults with various causes. For that, it refers to existing cause identification methods and categorizes modes by fault causes based on statistical techniques beforehand and performs the pretreatment process of fault currents by each cause acquired from the fault recorder into a topological plane in order to extract the characteristics of fault currents by each cause. After that, for the fault mode categorization, it discriminates modes by each cause using data by each cause as leaning data through utilizing RBF network based on FCM allowing self-organization in deciding the middle layer. And then it tests the validity of the suggested method as applying it to the data of the actual fault currents acquired from the fault recorder in the electric power transmission center.

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유전자 알고리즘기반 복수 분류모형 통합에 의한 할부금융고객의 신용예측모형 (A credit prediction model of a capital company′s customers using genetic algorithm based integration of multiple classifiers)

  • 이웅규;김홍철
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2001년도 추계학술대회 논문집
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    • pp.161-164
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    • 2001
  • 본 연구에서는 할부금융시장에서의 고객신용예측을 위한 모형으로 여러 가지 인공신경망(Neural Network) 모형들을 유전자 알고리즘(Genetic Algorithm)을 이용하여 통합한 신용예측모형을 제안한다. 10개의 학습된 인공신경망 모형들을 유전자알고리즘을 이용하여 종류별로 통합하여 MLP(Multi-Layered Perceptrons), Linear, RBF(Radial Basis Function) 세 가지의 대표모델을 얻고 이를 다시 하나의 인공신경망 모델로 통합하였다. 이를 통합되기 이전의 각각의 인공신경망 모형들과 성능을 비교, 분석하여 본 연구에서 제안한 통합모형의 유효성과 통합방법의 타당성을 제시하였다.

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