• Title/Summary/Keyword: RBF Neural Networks

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Genetically Optimization of Fuzzy C-Means Clustering based Fuzzy Neural Networks (Subtractive Clustering 알고리즘을 이용한 퍼지 RBF 뉴럴네트워크의 동정)

  • Choi, Jeoung-Nae;Oh, Sung-Kwun;Kim, Hyun-Ki
    • Proceedings of the KIEE Conference
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    • 2008.10b
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    • pp.239-240
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    • 2008
  • 본 논문에서는 Subtractive clustering 알고리즘을 이용한 Fuzzy Radial Basis Function Neural Network (FRBFNN)의 규칙 수를 자동적으로 생성하는 방법을 제시한다. FRBFNN은 멤버쉽 함수로써 기존 RBFNN에서 가우시안이나 타원형 형태의 특정 RBF를 사용하는 구조와 달리 Fuzzy C-Means clustering 알고리즘에서 사용하는 거리에 기한 멤버쉽 함수를 사용하여 전반부의 공간 분할 및 활성화 레벨을 결정하는 구조이다. 본 논문에서는 데이터의 밀집도에 기반을 두어 클러스터링을 하는 Subtractive clustering 알고리즘을 사용하여 퍼지 규칙의 수와 같은 의미를 갖는 분할할 입력공간의 수와 분할된 입력공간의 중심값을 동정하며, Least Square Estimator (LSE) 알고리즘을 사용하여 후반부 다항식의 계수를 추정 한다.

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Learning RBF Neural Networks by Active Data Selection (능동적인 데이터 선택에 의한 RBF 신경망의 학습)

  • 박상욱;장병탁
    • Proceedings of the Korean Information Science Society Conference
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    • 2000.04b
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    • pp.478-480
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    • 2000
  • 본 논문에서는 데이터를 능동적으로 선택하고, 그 데이터에 맞추어 RBF 은닉 뉴런을 증가시키는 신경망을 제안한다. 현재의 신경망에 대해서 가장 학습이 어려운 데이터를 선택해서 신경망을 학습하고, 학습한 신경망에 대해서 다시 에러가 가장 큰 데이터를 뽑아서 학습시키는 과정을 반복한다. 5개의 실세계 데이터에 대해 실험을 해보고, Platt이 제안한 RAN과 성능을 비교한다. 점진적으로 임계 데이터를 선택해서 학습을 함으로써, 전체 데이터를 다 사용하지도 않고도, 전체 데이터를 다 사용한 경우와 비슷한 성능을 보임을 실험을 통해서 알 수 있다.

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A vibration-based approach for detecting arch dam damage using RBF neural networks and Jaya algorithms

  • Ali Zar;Zahoor Hussain;Muhammad Akbar;Bassam A. Tayeh;Zhibin Lin
    • Smart Structures and Systems
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    • v.32 no.5
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    • pp.319-338
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    • 2023
  • The study presents a new hybrid data-driven method by combining radial basis functions neural networks (RBF-NN) with the Jaya algorithm (JA) to provide effective structural health monitoring of arch dams. The novelty of this approach lies in that only one user-defined parameter is required and thus can increase its effectiveness and efficiency, as compared to other machine learning techniques that often require processing a large amount of training and testing model parameters and hyper-parameters, with high time-consuming. This approach seeks rapid damage detection in arch dams under dynamic conditions, to prevent potential disasters, by utilizing the RBF-NNN to seamlessly integrate the dynamic elastic modulus (DEM) and modal parameters (such as natural frequency and mode shape) as damage indicators. To determine the dynamic characteristics of the arch dam, the JA sequentially optimizes an objective function rooted in vibration-based data sets. Two case studies of hyperbolic concrete arch dams were carefully designed using finite element simulation to demonstrate the effectiveness of the RBF-NN model, in conjunction with the Jaya algorithm. The testing results demonstrated that the proposed methods could exhibit significant computational time-savings, while effectively detecting damage in arch dam structures with complex nonlinearities. Furthermore, despite training data contaminated with a high level of noise, the RBF-NN and JA fusion remained the robustness, with high accuracy.

A Two-Stage Document Page Segmentation Method using Morphological Distance Map and RBF Network (거리 사상 함수 및 RBF 네트워크의 2단계 알고리즘을 적용한 서류 레이아웃 분할 방법)

  • Shin, Hyun-Kyung
    • Journal of KIISE:Software and Applications
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    • v.35 no.9
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    • pp.547-553
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    • 2008
  • We propose a two-stage document layout segmentation method. At the first stage, as top-down segmentation, morphological distance map algorithm extracts a collection of rectangular regions from a given input image. This preliminary result from the first stage is employed as input parameters for the process of next stage. At the second stage, a machine-learning algorithm is adopted RBF network, one of neural networks based on statistical model, is selected. In order for constructing the hidden layer of RBF network, a data clustering technique bared on the self-organizing property of Kohonen network is utilized. We present a result showing that the supervised neural network, trained by 300 number of sample data, improves the preliminary results of the first stage.

Relations among the multidimensional linear interpolation fuzzy reasoning , and neural networks

  • Om, Kyong-Sik;Kim, Hee-Chan;Byoung-Goo
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1998.06a
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    • pp.562-567
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    • 1998
  • This paper examined the relations among the multidimensional linear interpolation(MDI) and fuzzy reasoning , and neural networks, and showed that an showed that an MDI is a special form of Tsukamoto's fuzzy reasoning and regularization networks in the perspective of fuzzy reasoning and neural networks, respectively. For this purposes, we proposed a special Tsukamoto's membership (STM) systemand triangular basis function (TBF) networks, Also we verified the condition when our proposed TBF becomes a well-known radial basis function (RBF).

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Architectural Analysis of Type-2 Interval pRBF Neural Networks Using Space Search Evolutionary Algorithm (공간탐색 진화알고리즘을 이용한 Interval Type-2 pRBF 뉴럴 네트워크의 구조적 해석)

  • Oh, Sung-Kwun;Kim, Wook-Dong;Park, Ho-Sung;Lee, Young-Il
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.1
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    • pp.12-18
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    • 2011
  • In this paper, we proposed Interval Type-2 polynomial Radial Basis Function Neural Networks. In the receptive filed of hidden layer, Interval Type-2 fuzzy set is used. The characteristic of Interval Type-2 fuzzy set has Footprint Of Uncertainly(FOU), which denotes a certain level of robustness in the presence of un-known information when compared with the type-1 fuzzy set. In order to improve the performance of proposed model, we used the linear polynomial function as connection weight of network. The parameters such as center values of receptive field, constant deviation, and connection weight between hidden layer and output layer are optimized by Conjugate Gradient Method(CGM) and Space Search Evolutionary Algorithm(SSEA). The proposed model is applied to gas furnace dataset and its result are compared with those reported in the previous studies.

Classification of UTI Using RBF and LVQ Artificial Neural Network in Urine Dipstick Screening Test (RBF와 LVQ 인공신경망을 이용한 요(尿) 딥스틱 선별검사에서의 요로감염 분류)

  • Min, Kyoung-Kee;Kang, Myung-Seo;Shin, Ki-Young;Lee, Sang-Sik;Hun, Joung-Hwan
    • Journal of Biosystems Engineering
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    • v.33 no.5
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    • pp.340-347
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    • 2008
  • Dipstick urinalysis is used as a routine test for a screening test of UTI (urinary tract infection) in primary practice because urine dipstick test is simple. The result of dipstick urinalysis brings medical professionals to make a microscopic examination and urine culture for exact UTI diagnosis, therefore it is emphasized on a role of screening test. The objective of this study was to the classification between UTI patients and normal subjects using hybrid neural network classifier with enhanced clustering performance in urine dipstick screening test. In order to propose a classifier, we made a hybrid neural network which combines with RBF layer, summation & normalization layer and L VQ artificial neural network layer. For the demonstration of proposed hybrid neural network, we compared proposed classifier with various artificial neural networks such as back-propagation, RBFNN and PNN method. As a result, classification performance of proposed classifier was able to classify 95.81% of the normal subjects and 83.87% of the UTI patients, total average 90.72% according to validation dataset. The proposed classifier confirms better performance than other classifiers. Therefore the application of such a proposed classifier expect to utilize telemedicine to classify between UTI patients and normal subjects in the future.

Predicting PM2.5 Concentrations Using Artificial Neural Networks and Markov Chain, a Case Study Karaj City

  • Asadollahfardi, Gholamreza;Zangooei, Hossein;Aria, Shiva Homayoun
    • Asian Journal of Atmospheric Environment
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    • v.10 no.2
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    • pp.67-79
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    • 2016
  • The forecasting of air pollution is an important and popular topic in environmental engineering. Due to health impacts caused by unacceptable particulate matter (PM) levels, it has become one of the greatest concerns in metropolitan cities like Karaj City in Iran. In this study, the concentration of $PM_{2.5}$ was predicted by applying a multilayer percepteron (MLP) neural network, a radial basis function (RBF) neural network and a Markov chain model. Two months of hourly data including temperature, NO, $NO_2$, $NO_x$, CO, $SO_2$ and $PM_{10}$ were used as inputs to the artificial neural networks. From 1,488 data, 1,300 of data was used to train the models and the rest of the data were applied to test the models. The results of using artificial neural networks indicated that the models performed well in predicting $PM_{2.5}$ concentrations. The application of a Markov chain described the probable occurrences of unhealthy hours. The MLP neural network with two hidden layers including 19 neurons in the first layer and 16 neurons in the second layer provided the best results. The coefficient of determination ($R^2$), Index of Agreement (IA) and Efficiency (E) between the observed and the predicted data using an MLP neural network were 0.92, 0.93 and 0.981, respectively. In the MLP neural network, the MBE was 0.0546 which indicates the adequacy of the model. In the RBF neural network, increasing the number of neurons to 1,488 caused the RMSE to decline from 7.88 to 0.00 and caused $R^2$ to reach 0.93. In the Markov chain model the absolute error was 0.014 which indicated an acceptable accuracy and precision. We concluded the probability of occurrence state duration and transition of $PM_{2.5}$ pollution is predictable using a Markov chain method.

RBF Neural Networks-Based Adaptive Noise Filtering from the ECG Signal (방사기저함수 신경망을 기반한 ECG신호의 적응펄터링)

  • 이주원;이한욱;이종회;장두봉;김영일;이건기
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.1159-1162
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    • 1999
  • The ECG signal is very important information for diagnosis of patient and a cardiac disorder. It is hard to remove the noise because that is mixed with a lot of noise, and the error of the filtering will distort the ECG signal. The existing method for the filtering of the ECG signal has structure that has many steps for filtering, so that structure is complex and the processing speed is slow. For the improvement of that problem, we propose the method of filtering that has simple structure using the RBF neural networks and have good results.

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Forecasting of Runoff Hydrograph Using Neural Network Algorithms (신경망 알고리즘을 적용한 유출수문곡선의 예측)

  • An, Sang-Jin;Jeon, Gye-Won;Kim, Gwang-Il
    • Journal of Korea Water Resources Association
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    • v.33 no.4
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    • pp.505-515
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    • 2000
  • THe purpose of this study is to forecast of runoff hydrographs according to rainfall event in a stream. The neural network theory as a hydrologic blackbox model is used to solve hydrological problems. The Back-Propagation(BP) algorithm by the Levenberg-Marquardt(LM) techniques and Radial Basis Function(RBF) network in Neural Network(NN) models are used. Runoff hydrograph is forecasted in Bocheongstream basin which is a IHP the representative basin. The possibility of a simulation for runoff hydrographs about unlearned stations is considered. The results show that NN models are performed to effective learning for rainfall-runoff process of hydrologic system which involves a complexity and nonliner relationships. The RBF networks consist of 2 learning steps. The first step is an unsupervised learning in hidden layer and the next step is a supervised learning in output layer. Therefore, the RBF networks could provide rather time saved in the learning step than the BP algorithm. The peak discharge both BP algorithm and RBF network model in the estimation of an unlearned are a is trended to observed values.

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