To improve on-line modeling precision of support vector regression(SVR)in uncertain control systems
by analyzing the effects of training data sets distribution and outliers
it is demonstrated that the precision can be effectively improved by increasing data density at neighborhood of outliers. A modeling method using multirate sampling is presented based on on-line SVR. In this method
multirate sampling is chosen to increase local data density
and a local-data-intensive sliding time window is established to reduce the training data number and eliminate outliers by taking advantage of the good performance of SVR in small sample. The method is applied to a multichannel electrohydraulic force servo synchronous loading system to predict the load output. Compared with the traditional single rate sampling method
the results indicatethe better robustness and prediction accuracy. The prediction mean absolute percentage error gets 0.66% while only two training samples are added.
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references
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