Estimation of Collapse Moment for Wall Thinned Elbows Using Fuzzy Neural Networks

  • Na, Man-Gyun (Dept. of Nuclear Engineering, Chosun University) ;
  • Kim, Jin-Weon (Dept. of Nuclear Engineering, Chosun University) ;
  • Shin, Sun-Ho (Dept. of Nuclear Engineering, Chosun University) ;
  • Kim, Koung-Suk (Dept. of Mechanical Information Engineering, Chosun University) ;
  • Kang, Ki-Soo (Dept. of Mechanical Information Engineering, Chosun University)
  • Published : 2004.08.30

Abstract

In this work, the collapse moment due to wall-thinning defects is estimated by using fuzzy neural networks. The developed fuzzy neural networks have been applied to the numerical data obtained from the finite element analysis. Principal component analysis is used to preprocess the input signals into the fuzzy neural network to reduce the sensitivity to the input change and the fuzzy neural networks are trained by using the data set prepared for training (training data) and verified by using another data set different (independent) from the training data. Also, two fuzzy neural networks are trained for two data sets divided into the two classes of extrados and intrados defects, which is because they have different characteristics. The relative 2-sigma errors of the estimated collapse moment are 3.07% for the training data and 4.12% for the test data. It is known from this result that the fuzzy neural networks are sufficiently accurate to be used in the wall-thinning monitoring of elbows.

Keywords

References

  1. M. A. Shalaby, and M. Y. A. Younan, 'Limit loads for pipe elbows subjected to in-plane opening moments and internal pressure, J. of Press. Ves. Tech., Vol. 121, pp. 17-23, (1999) https://doi.org/10.1115/1.2883661
  2. B. Chexal , J. Horowitz, B. Dooley, P. Millett, C. Wood, and R. Jones , 'Flow-Accelerated Corrosion in Power Plant,' EPRl/TR-106611-R2 , (1998)
  3. J. W. Hines, D. J. Wrest, and R. E. Uhrig, 'Signal validation using an adaptive neural fuzzy inference system,' Nucl. Technology, Vol. 119, No.2, pp. 181-193, (1997) https://doi.org/10.13182/NT97-A35385
  4. P. Fantoni , S. Figedy, and A. Racz, 'A neuro-fuzzy model applied full range signal validation of PWR nuclear power plant data,' FLINS-98 , Antwerpen , Belgium, (1998)
  5. M. G. Na, Y. R. Sim, K. H. Park, S. M. Lee, D. W. Jung, S. H. Shin, B. R. Upadhyaya, K. Zhao, and B. Lu, 'Sensor monitoring using a fuzzy neural network with an automatic structure constructor,' IEEE Trans. Nucl. Sci., Vol. 50, No.2, pp. 241-250, (2003) https://doi.org/10.1109/TNS.2003.809471
  6. E. B. Bartlett and R. E. Uhrig, 'Nuclear power plant diagnostics using an artificial neural network,' Nucl. Technol., Vol. 97, pp. 272-281, (1992)
  7. M. Marseguerra and E. Zio, 'Fault diagnosis via neural networks: The Boltzmann machine,' Nucl. Sci. Eng., Vol. 117, No. 3, pp. 194-200, (1994) https://doi.org/10.13182/NSE94-A28534
  8. H. G. Kim, S. H. Chang, and B. H. Lee, 'Optimal fuel loading pattern design using an artificial neural network and a fuzzy rule-based system,' Nucl. Sci. Eng., Vol. 115, No. 2, pp. 152-163, (1993) https://doi.org/10.13182/NSE93-A28525
  9. J. H. Lee, H. J. Sim, C. S. Jang, and C. H. Kim, 'Incorporation of neural networks into simulated annealing algorithm for fuel assembly loading pattern optimization in a PWR,' Proc. Int. Conf. on Phys. of Nucl. Sci. and Technol., Long Island, New York, October 5-8, Vol. 1, p. 75, American Nuclear Society, (1998)
  10. M. G. Na, 'Design of a genetic fuzzy controller for the nuclear steam generator water level control,' IEEE Trans. Nucl. Sci., Vol. 45, No. 4, pp. 2261-2271, (1998) https://doi.org/10.1109/23.709657
  11. Y. Bartal, J. Lin, and R. E. Uhrig, 'Nuclear power plant transient diagnostics using artificial neural networks that allow 'don’t-know' classifications,' Nucl. Technol., Vol. 110, No. 3, pp. 436-449, (1995)
  12. C. H. Roh, H. S. Chang, H. G. Kim, and S. H. Chang, 'Identification of reactor vessel failures using spatiotemporal neural networks,' IEEE Trans. Nucl. Sci., Vol. 43, No.6, pp. 3223-3229, (1996) https://doi.org/10.1109/23.552722
  13. X. Z. Wang and R. F. Li, 'Combining conceptual clustering and principal component analysis for state space based process monitoring,' Ind. Eng. Chem. Res., Vol. 38, No. 11, pp. 4345-4358, (1999) https://doi.org/10.1021/ie990144q
  14. Junghui Chen and Jialin Liu, 'Mixture principal component analysis models for process monitoring,' Ind. Eng. Chem. Res., Vol. 38, No.4, pp. 1478-1488, (1999) https://doi.org/10.1021/ie980577d
  15. Hibbitt, Karlson and Sorensen Inc., 'ABAQUS User’s Manual', (2001)
  16. V. C. Martzen, and L. Yu, 'Elbow stress indices using finite element analysis,' Nucl. Eng. & Des, Vol. 181, pp. 257-265, (1998) https://doi.org/10.1016/S0029-5493(97)00352-X
  17. J. -S. Roger Jang, 'ANFIS: Adaptive-network-based fuzzy inference systems, ' IEEE Transactions on Systems, Man, and Cybernetics, Vol. 23, No.3, pp 665-685, (1993)
  18. T. Takagi and M. Sugeno, 'Fuzzy identification of systems and its applications to modeling and control,' IEEE Trans. System, Man, Cybern., Vol. 1, pp. 116-132, (1985)