• Title/Summary/Keyword: GMDH algorithm

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A Study on the Performance Improvement of GMDH Algorithm by Feedback (피드백에 의한 GMDH 알고리듬 성능 향상에 관한 연구)

  • Hong, Yeon-Chan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.3
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    • pp.559-564
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    • 2010
  • The GMDH(Group Method of Data Handling) algorithm can be used to predict the complex nonlinear systems. The traditional GMDH algorithm produces the prdicted output of the system model in the output layer through the input layer and the intermediate layers as the prescribed process. The outputs of each layer are produced only by the outputs of the former layer. However, in the traditional GMDH algorithm, though the optimal structure of each layer is derived, the overall structure may not be derived optimally. To overcome this problem, GMDH prediction model which has the overall optimal structure is constructed by feeding back the error between the predicted output and the real output. This can make the prediction more precise. The capability improvement of the proposed algorithm compared to the traditional algorithm is verified through computer simulation.

GMDH Algorithm with Data Weighting Performance and Its Application to Power Demand Forecasting (데이터 가중 성능을 갖는 GMDH 알고리즘 및 전력 수요 예측에의 응용)

  • Shin Jae-Ho;Hong Yeon-Chan
    • Journal of Institute of Control, Robotics and Systems
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    • v.12 no.7
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    • pp.631-636
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    • 2006
  • In this paper, an algorithm of time series function forecasting using GMDH(group method of data handling) algorithm that gives more weight to the recent data is proposed. Traditional methods of GMDH forecasting gives same weights to the old and recent data, but by the point of view that the recent data is more important than the old data to forecast the future, an algorithm that makes the recent data contribute more to training is proposed for more accurate forecasting. The average error rate of electric power demand forecasting by the traditional GMDH algorithm which does not use data weighting algorithm is 0.9862 %, but as the result of applying the data weighting GMDH algorithm proposed in this paper to electric power forecasting demand the average error rate by the algorithm which uses data weighting algorithm and chooses the best data weighting rate is 0.688 %. Accordingly in forecasting the electric power demand by GMDH the proposed method can acquire the reduced error rate of 30.2 % compared to the traditional method.

Modeling of Nonlinear Dynamic Dynamic Systems Using a Modified GMDH Algorithm (수정된 GMDH 알고리즘을 이용한 비선형 동적 시스템의 모델링)

  • 홍연찬;엄상수
    • Journal of the Korean Institute of Intelligent Systems
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    • v.8 no.3
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    • pp.50-55
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    • 1998
  • The GMDH(Group Method of Data Handling) is a useful data analysis technique for identification of nonlinear complex systems. Therefore, in this paper the application method of GMDH algorithm for modeling nonlinear dynamic systems is proposed. The identification of dynamic systems by using GMDH consists of applying a set of input/output data and computing the necessary coefficient set dynamically. Also, in this paper, by reducing sequentially the criterion which can adopt or reject the data, a method to prevent excessive computation that is a disadvantage of GMDH is proposed.

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Improvement of Modeling Capability of GMDH Algorithm with Interlayer Connection (층간 연결에 의한 GMDH 알고리듬의 모델링 성능 향상)

  • Hong, Yeon-Chan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.6
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    • pp.1200-1207
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    • 2009
  • The GMDH(Group Method of Data Handling) algorithm can be used to model the complex nonlinear systems. The traditional GMDH algorithm produces the output of the system model in the output layer through the input layer and the intermediate layers as the prescribed process. The outputs of each layer are produced only by the outputs of the former layer. However among the inputs there may be the inputs which can influence the modeling result more than the other inputs. Therefore in this paper the method which improve the modeling capability by interlayer connection of more influential inputs is proposed. The capability improvement of the proposed algorithm compared to the traditional algorithm is verified through computer simulation.

A design on model following control system of DC servo motor using GMDH algorithm (GMDH 알고리즘에 의한 직류 서보 전동기의 모델추종형 제어계 구성에 관한 연구)

  • 황창선;김문수;이양우;김동완
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.1044-1047
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    • 1996
  • In this paper, GMDH(Group Method of Data Handling) algorithm, which is based on heuristic self organization to predict and identify the complex system, is applied to the control system of DC servo motor. The mathematical relation between input voltage and motor speed is obtained by GMDH algorithm. A design method of model following control system based on GMDH algorithm is developed. As a result of applying this method to DC servo motor, the simulation and experiment have shown that the developed method gives a good performance in tracking the reference model and in rejection of disturbance, in spite of constant load and changing load.

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Short-term Electric Load Forecasting Based on Wavelet Transform and GMDH

  • Koo, Bon-Gil;Lee, Heung-Seok;Park, Juneho
    • Journal of Electrical Engineering and Technology
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    • v.10 no.3
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    • pp.832-837
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    • 2015
  • The group method of data handling (GMDH) algorithm has proven to be a powerful and effective way to extract rules or polynomials from an electric load pattern. However, because it is nonstationary, the load pattern needs to be decomposed using a discrete wavelet transform. In addition, if a load pattern has a complicated curve pattern, GMDH should use a higher polynomial, which requires complex computing and consumes a lot of time. This paper suggests a method for short-term electric load forecasting that uses a wavelet transform and a GMDH algorithm. Case studies with the proposed algorithm were carried out for one-day-ahead forecasting of hourly electric loads using data during the years 2008-2011. To prove the effectiveness of our proposed approach, the results were evaluated and compared with those obtained by Holt-Winters method and artificial neural network. Our suggested method resulted in better performance than either comparison group.

A Study onthe Modelling and control Using GMDH Algorithm (GMDH 알고리즘을 이용한 모델링 및 제어에 관한 연구)

  • 최종헌;홍연찬
    • Journal of the Korean Institute of Intelligent Systems
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    • v.7 no.3
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    • pp.65-71
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    • 1997
  • With the emergence of neural network, there is a revived interest in identification of nonlinear systems. So in this paper, to identify unknown nonlinear systems dynamically we propose DPNN(Dynamic Polynomial Neural Network) using GMDH (Group Method of Data Handling) algorithm. The dynamic system identification using GMDH consists of applying a set of inputloutput data to train the network by dynamically computing the necessary coeffici1:nt sets. Then, MRAC(Mode1 Reference Adaptive Control) is designed to control nonlinear systems using DPNN. In the result, we can see that the modelling and control using DPNN work well by computer simulation.

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Fuzzy GMDH Model and Its Application to the Sewage Treatment Process (퍼지 GMDH 모델과 하수처리공정에의 응용)

  • 노석범;오성권;황형수;박희순
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1995.10b
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    • pp.153-158
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    • 1995
  • In this paper, A new design method of fuzzy modeling is presented for the model identification of nonlinear complex systems. The proposed fuzzy GMDH modeling implements system structure and parameter identification using GMDH(Group Method of Data Handling) algorithm and linguistic fuzzy implication rules from input and output data of processes. In order to identify premise structure and parameter of fuzzy implication rules, GMDH algorithm and fuzzy reasoning method are used and the least square method is utilized for the identification of optimum consequence parameters. Time series data for gas furnaceare those for sewage treatment process are used for the purpose of evaluating the performance of the proposed fuzzy GMDH modeling. The results show that the proposed method can produce the fuzzy model with higher accuracy than other works achieved previously.

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Prediction of California bearing ratio (CBR) for coarse- and fine-grained soils using the GMDH-model

  • Mintae Kim;Seyma Ordu;Ozkan Arslan;Junyoung Ko
    • Geomechanics and Engineering
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    • v.33 no.2
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    • pp.183-194
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    • 2023
  • This study presents the prediction of the California bearing ratio (CBR) of coarse- and fine-grained soils using artificial intelligence technology. The group method of data handling (GMDH) algorithm, an artificial neural network-based model, was used in the prediction of the CBR values. In the design of the prediction models, various combinations of independent input variables for both coarse- and fine-grained soils have been used. The results obtained from the designed GMDH-type neural networks (GMDH-type NN) were compared with other regression models, such as linear, support vector, and multilayer perception regression methods. The performance of models was evaluated with a regression coefficient (R2), root-mean-square error (RMSE), and mean absolute error (MAE). The results showed that GMDH-type NN algorithm had higher performance than other regression methods in the prediction of CBR value for coarse- and fine-grained soils. The GMDH model had an R2 of 0.938, RMSE of 1.87, and MAE of 1.48 for the input variables {G, S, and MDD} in coarse-grained soils. For fine-grained soils, it had an R2 of 0.829, RMSE of 3.02, and MAE of 2.40, when using the input variables {LL, PI, MDD, and OMC}. The performance evaluations revealed that the GMDH-type NN models were effective in predicting CBR values of both coarse- and fine-grained soils.

Performance Improvement of Nonlinear System Modeling Using GMDH (GMDH를 이용한 비선형 시스템의 모델링 성능 개선)

  • Hong, Yeon-Chan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.7
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    • pp.1544-1550
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    • 2010
  • There have been many researches applying GMDH for modelling nonlinear dynamic systems. However, these methods require a great amount of computation in return of the accuracy. Thus, in this paper, we propose a method to reduce the amount of computation in GMDH by adjusting the adopting criterion of input data in decrement while at least maintaining the accuracy. The simulation result verifies that the proposed method can successfully reduce the amount of computation without the expense of the error rate, if not significantly better.