• Title/Summary/Keyword: neural networks

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Development of Temporal Disaggregation Model using Neural Networks 1. Application of the Historic Data (신경망모형을 이용한 시간적 분해모형의 개발 1. 실측자료의 적용)

  • Kim, Seong-Won;Kim, Jeong-Heon;Park, Gi-Beom
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1207-1210
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    • 2009
  • The goal of this research is to apply the neural networks models for the disaggregation of the pan evaporation (PE) data, Republic of Korea. The neural networks models consist of generalized regression neural networks model (GRNNM) and multilayer perceptron neural networks model (MLP-NNM), respectively. The disaggregation means that the yearly PE data divides into the monthly PE data. And, for the performances of the neural networks models, they are composed of training and test performances, respectively. The training and test performances consist of the only historic data, respectively. From this research, we evaluate the impact of GRNNM and MLP-NNM for the disaggregation of the nonlinear time series data. We should, furthermore, construct the credible data of the monthly PE data from the disaggregation of the yearly PE data, and can suggest the methodology for the irrigation and drainage networks system.

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Development of Temporal Disaggregation Model using Neural Networks 3. Application of the Mixed Data (신경망모형을 이용한 시간적 분해모형의 개발 3. 혼합자료의 적용)

  • Kim, Seong-Won
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1215-1218
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    • 2009
  • The goal of this research is to apply the neural networks models for the disaggregation of the pan evaporation (PE) data, Republic of Korea. The neural networks models consist of generalized regression neural networks model (GRNNM) and multilayer perceptron neural networks model (MLP-NNM), respectively. The disaggregation means that the yearly PE data divides into the monthly PE data. And, for the performances of the neural networks models, they are composed of training and test performances, respectively. The training data consist of the mixed data The mixed data involves the historic data and the generated data using PARMA (1,1). And, the testing data consist of the only historic data, respectively. From this research, we evaluate the impact of GRNNM and MLP-NNM for the disaggregation of the nonlinear time series data. We should, furthermore, construct the credible data of the monthly PE data from the disaggregation of the yearly PE data, and can suggest the methodology for the irrigation and drainage networks system.

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Development of Temporal Disaggregation Model using Neural Networks 2. Application of the Generated Data (신경망모형을 이용한 시간적 분해모형의 개발 2. 모의자료의 적용)

  • Kim, Seong-Won
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1211-1214
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    • 2009
  • The goal of this research is to apply the neural networks models for the disaggregation of the pan evaporation (PE) data, Republic of Korea. The neural networks models consist of generalized regression neural networks model (GRNNM) and multilayer perceptron neural networks model (MLP-NNM), respectively. The disaggregation means that the yearly PE data divides into the monthly PE data. And, for the performances of the neural networks models, they are composed of training and test performances, respectively. The training data consist of the generated data using PARMA (1,1). And, the testing data consist of the historic data, respectively. From this research, we evaluate the impact of GRNNM and MLP-NNM for the disaggregation of the nonlinear time series data. We should, furthermore, construct the credible data of the monthly PE data from the disaggregation of the yearly PE data, and can suggest the methodology for the irrigation and drainage networks system.

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Modeling of Hydrologic Time Series using Stochastic Neural Networks Approach (추계학적 신경망 접근법을 이용한 수문학적 시계열의 모형화)

  • Kim, Seong-Won;Kim, Jeong-Heon;Park, Gi-Beom
    • Proceedings of the Korea Water Resources Association Conference
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    • 2010.05a
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    • pp.1346-1349
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    • 2010
  • The goal of this research is to apply the neural networks models for the disaggregation of the pan evaporation (PE) data, Republic of Korea. The neural networks models consist of generalized regression neural networks model (GRNNM) and multilayer perceptron neural networks model (MLP-NNM), respectively. The disaggregation means that the yearly PE data divides into the monthly PE data. And, for the performances of the neural networks models, they are composed of training and test performances, respectively. The training and test performances consist of the historic, the generated, and the mixed data, respectively. From this research, we evaluate the impact of GRNNM and MLP-NNM for the disaggregation of the nonlinear time series data. We should, furthermore, construct the credible data of the monthly PE from the disaggregation of the yearly PE data, and can suggest the methodology for the irrigation and drainage networks system.

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Evolutionary designing neural networks structures using genetic algorithm

  • Itou, Minoru;Sugisaka, Masanori
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.43.2-43
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    • 2001
  • In this paper, we consider the problems of the evolutionary designed neural networks structures by genetic algorithm. Neural networks has been applied to various application fields since back-propagation algorithm was proposed, e.g. function approximation, pattern or character recognition and so on. However, one of difficulties to use the neural networks. It is how to design the structure of the neural network. Researchers and users design networks structures and training parameters such as learning rate and momentum rate and so on, by trial and error based on their experiences. In the case of designing large scales neural networks, it is very hard work for manually design by try and error. For this difficulty, various structural learning algorithms have been proposed. Especially, the technique of using genetic algorithm for networks structures design has been ...

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Squint Free Phased Array Antenna System using Artificial Neural Networks

  • Kim, Young-Ki;Jeon, Do-Hong;Thursby, Michael
    • The Journal of Korean Association of Computer Education
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    • v.6 no.3
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    • pp.47-56
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    • 2003
  • We describe a new method for removing non-linear phased array antenna aberration called "squint" problem. To develop a compensation scheme. theoretical antenna and artificial neural networks were used. The purpose of using the artificial neural networks is to develop an antenna system model that represents the steering function of an actual array. The artificial neural networks are also used to implement an inverse model which when concatenated with the antenna or antenna model will correct the "squint" problem. Combining the actual steering function and the inverse model contained in the artificial neural network, alters the steering command to the antenna so that the antenna will point to the desired position instead of squinting. The use of an artificial neural network provides a method of producing a non-linear system that can correct antenna performance. This paper demonstrates the feasibility of generating an inverse steering algorithm with artificial neural networks.

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Multiple component neural network architecture design and learning by using PCA (PCA를 이용한 다중 컴포넌트 신경망 구조설계 및 학습)

  • 박찬호;이현수
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.10
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    • pp.107-119
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    • 1996
  • In this paper, we propose multiple component neural network(MCNN) which learn partitioned patterns in each multiple component neural networks by reducing dimensions of input pattern vector using PCA (principal component analysis). Procesed neural network use Oja's rule that has a role of PCA, output patterns are used a slearning patterns on small component neural networks and we call it CBP. For simply not solved patterns in a network, we solves it by regenerating new CBP neural networks and by performing dynamic partitioned pattern learning. Simulation results shows that proposed MCNN neural networks are very small size networks and have very fast learning speed compared with multilayer neural network EBP.

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Estimating Evapotranspiration of Rice Crop Using Neural Networks -Application of Back-propagation and Counter-propagation Algorithm- (신경회로망을 이용한 수도 증발산량 예측 -백프로파게이션과 카운터프로파게이션 알고리즘의 적용-)

  • 이남호;정하우
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.36 no.2
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    • pp.88-95
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    • 1994
  • This paper is to evaluate the applicability of neural networks to the estimation of evapotranspiration. Two neural networks were developed to forecast daily evapotranspiration of the rice crop with back-propagation and counter-propagation algorithm. The neural network trained by back-propagation algorithm with delta learning rule is a three-layer network with input, hidden, and output layers. The other network with counter-propagation algorithm is a four-layer network with input, normalizing, competitive, and output layers. Training neural networks was conducted using daily actual evapotranspiration of rice crop and daily climatic data such as mean temperature, sunshine hours, solar radiation, relative humidity, and pan evaporation. During the training, neural network parameters were calibrated. The trained networks were applied to a set of field data not used in the training. The created response of the back-propagation network was in good agreement with desired values and showed better performances than the counter-propagation network did. Evaluating the neural network performance indicates that the back-propagation neural network may be applied to the estimation of evapotranspiration of the rice crop. This study does not provide with a conclusive statement as to the ability of a neural network to evapotranspiration estimating. More detailed study is required for better understanding and evaluating the behavior of neural networks.

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Rule-Based Fuzzy Polynomial Neural Networks in Modeling Software Process Data

  • Park, Byoung-Jun;Lee, Dong-Yoon;Oh, Sung-Kwun
    • International Journal of Control, Automation, and Systems
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    • v.1 no.3
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    • pp.321-331
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    • 2003
  • Experimental software datasets describing software projects in terms of their complexity and development time have been the subject of intensive modeling. A number of various modeling methodologies and modeling designs have been proposed including such approaches as neural networks, fuzzy, and fuzzy neural network models. In this study, we introduce the concept of the Rule-based fuzzy polynomial neural networks (RFPNN) as a hybrid modeling architecture and discuss its comprehensive design methodology. The development of the RFPNN dwells on the technologies of Computational Intelligence (CI), namely fuzzy sets, neural networks, and genetic algorithms. The architecture of the RFPNN results from a synergistic usage of RFNN and PNN. RFNN contribute to the formation of the premise part of the rule-based structure of the RFPNN. The consequence part of the RFPNN is designed using PNN. We discuss two kinds of RFPNN architectures and propose a comprehensive learning algorithm. In particular, it is shown that this network exhibits a dynamic structure. The experimental results include well-known software data such as the NASA dataset concerning software cost estimation and the one describing software modules of the Medical Imaging System (MIS).

Stabilization Position Control of a Ball-Beam System Using Neural Networks Controller (신경회로망 제어기을 이용한 볼-빔 시스템의 안정화 위치제어)

  • 탁한호;추연규
    • Journal of the Korean Institute of Navigation
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    • v.23 no.3
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    • pp.35-44
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    • 1999
  • This research aims to seek active control of ball-beam position stability by resorting to neural networks whose layers are given bias weights. The controller consists of an LQR (linear quadratic regulator) controller and a neural networks controller in parallel. The latter is used to improve the responses of the established LQR control system, especially when controlling the system with nonlinear factors or modelling errors. For the learning of this control system, the feedback-error learning algorithm is utilized here. While the neural networks controller learns repetitive trajectories on line, feedback errors are back-propagated through neural networks. Convergence is made when the neural networks controller reversely learns and controls the plant. The goals of teaming are to expand the working range of the adaptive control system and to bridge errors owing to nonlinearity by adjusting parameters against the external disturbances and change of the nonlinear plant. The motion equation of the ball-beam system is derived from Newton's law. As the system is strongly nonlinear, lots of researchers have depended on classical systems to control it. Its applications of position control are seen in planes, ships, automobiles and so on. However, the research based on artificial control is quite recent. The current paper compares and analyzes simulation results by way of the LQR controller and the neural network controller in order to prove the efficiency of the neural networks control algorithm against any nonlinear system.

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