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UNCERTAINTY ANALYSIS OF DATA-BASED MODELS FOR ESTIMATING COLLAPSE MOMENTS OF WALL-THINNED PIPE BENDS AND ELBOWS

  • Kim, Dong-Su (Korea Atomic Energy Research Institute) ;
  • Kim, Ju-Hyun (Department of Nuclear Engineering, Chosun University) ;
  • Na, Man-Gyun (Department of Nuclear Engineering, Chosun University) ;
  • Kim, Jin-Weon (Department of Nuclear Engineering, Chosun University)
  • Received : 2011.06.13
  • Accepted : 2011.07.14
  • Published : 2012.04.25

Abstract

The development of data-based models requires uncertainty analysis to explain the accuracy of their predictions. In this paper, an uncertainty analysis of the support vector regression (SVR) model, which is a data-based model, was performed because previous research showed that the SVR method accurately estimates the collapse moments of wall-thinned pipe bends and elbows. The uncertainty analysis method used in this study was an analytic uncertainty analysis method, and estimates with a 95% confidence interval were obtained for 370 test data points. From the results, the prediction interval (PI) was very narrow, which means that the predicted values are quite accurate. Therefore, the proposed SVR method can be used effectively to assess and validate the integrity of the wall-thinned pipe bends and elbows.

Keywords

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