DOI QR코드

DOI QR Code

INVESTIGATION OF REACTOR CONDITION MONITORING AND SINGULARITY DETECTION VIA WAVELET TRANSFORM AND DE-NOISING

  • Kim, Ok-Joo (Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology) ;
  • Cho, Nan-Zin (Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology) ;
  • Park, Chang-Je (Korea Atomic Energy Research Institute) ;
  • Park, Moon-Ghu (Korea Electric Power Research Institute)
  • 발행 : 2007.06.30

초록

Wavelet theory was applied to detect a singularity in a reactor power signal. Compared to Fourier transform, wavelet transform has localization properties in space and frequency. Therefore, using wavelet transform after de-noising, singular points can easily be found. To test this theory, reactor power signals were generated using the HANARO(a Korean multi-purpose research reactor) dynamics model consisting of 39 nonlinear differential equations contaminated with Gaussian noise. Wavelet transform decomposition and de-noising procedures were applied to these signals. It was possible to detect singular events such as a sudden reactivity change and abrupt intrinsic property changes. Thus, this method could be profitably utilized in a real-time system for automatic event recognition(e.g., reactor condition monitoring).

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참고문헌

  1. I. Daubechies, 'Orthonormal Bases of Compactly Supported Wavelets,' Comm. Pure. Appl. Math., 41, 909 (1988) https://doi.org/10.1002/cpa.3160410705
  2. G. Strang, 'Wavelets and Dilation Equations: A Brief Introduction,' SIAM Rev., 31, 614 (1989) https://doi.org/10.1137/1031128
  3. R. Glowinski, W. Lawton, M. Ravachol, and E. Tenenbaum, 'Wavelet Solution of Linear and Nonlinear Elliptic, Parabolic and Hyperbolic Problems in One Space Dimension,' in Comput. Methods Appl. Sci. Eng, SIAM, Philadelphia, 55 (1990)
  4. N. Z. Cho and C. J. Park, 'Wavelet Theory for Solution of the Neutron Diffusion Equation,' Nucl. Sci. Eng., 124, 417 (1996) https://doi.org/10.13182/NSE96-A17920
  5. H. Nasif, R. Omori, and A. Suzuki, 'Improved Solution of the Neutron Diffusion Equation Using Wavelet Theory,' J. Nucl. Sci. Technol., 36 [9], 839 (1999) https://doi.org/10.3327/jnst.36.839
  6. N. Z. Cho and L. Cao, 'Wavelet-theoretic Method for Solution of Neutron Transport Equation', in Proc. Korean Nuclear Society Spring Mtg., Chuncheon, Korea, CD-ROM (2006)
  7. Thie, J. A., Reactor Noise, Rowman and Littlefield, Inc, New York (1963)
  8. Thie, J. A., Power Reactor Noise, American Nuclear Society, La Grange Park, IL (1981)
  9. Uhrig, R. E., Random Noise Techniques in Nuclear Reactor Systems, The Ronald Press Company, New York (1970)
  10. Williams, M. M. R., Random Processes in Nuclear Reactors, Pergamon Press, Oxford (1974)
  11. Uhrig, R. E., 'Integrating Neural Network Technology and Noise Analysis,' Progress in Nuclear Energy, 29, 357 (1995) https://doi.org/10.1016/0149-1970(95)00018-F
  12. Uhrig, R. E. and Tsoukalas, L. H., 'Soft Computing Technologies in Nuclear Engineering Applications,' Progress in Nuclear Energy, 34, 13 (1999) https://doi.org/10.1016/S0149-1970(97)00109-1
  13. Hines, J. W. and Uhrig, R. E., 'Trends in Computational Intelligence in Nuclear Engineering,' Progress in Nuclear Energy, 46, 167 (2005) https://doi.org/10.1016/j.pnucene.2005.03.002
  14. G. Beylkin, R. Coifman, and V. Rokhlin, 'Fast Wavelet Transforms and Numerical Algorithms,' Comm. Pure. Appl. Math, 43, 141 (1991)
  15. S. Mallat and W.L. Hwang, 'Singularity Detection and Processing with Wavelets,' IEEE Trans. Inform. Theory, 38, 617 (1992) https://doi.org/10.1109/18.119727
  16. D. L. Donoho, 'De-noising by Soft Thresholding,' IEEE Trans. Inform. Theory, 41, 613 (1995) https://doi.org/10.1109/18.382009
  17. T. W. Noh, B.S. Sim, Bo. W. Rhee, and S. K. Oh, 'Korea Multipurpose Research Reactor,' Korea Atomic Energy Research Institute, Tech. Rep. KM-031-400-02 (1989)
  18. C. J. Park and N. Z. Cho, 'Reactor Condition Monitoring via Wavelet Transform De-noising,' in Proc. Korean Nuclear Society Autumn Mtg., Daejeon, Korea, 67 (1996)
  19. B. J. Yoon and P. P. Vaidyanathan, 'Wavelet-based Denoising by Customized Thresholding,' in Proc. 29th IEEE Int. Conf. Acoustics, Speech, and Signal Processing, 2, 925 (2004)
  20. S. G. Chang, B. Yu, and M. Vetterli, 'Adaptive Wavelet Thresholding for Image Denoising and Compression,' IEEE Trans. Image Processing, 9, 1532 (2000) https://doi.org/10.1109/83.862633