DOI QR코드

DOI QR Code

A continuous solution of the heat equation based on a fuzzy system

  • 발행 : 2003.06.01

초록

A continuous solution of the Dirichlet boundary value problem for the heat equation $u_t$$a2u_{xx}$ using a fuzzy system is described. We first apply the Crank-Nicolson method to obtain a discrete solution at the grid points for the heat equation. Then we find a continuous function to represent approximately the discrete values at the grid points in the form of a bicubic spline function (equation omitted) that can in turn be represented exactly by a fuzzy system. We show that the computed values at non-grid points using the bicubic spline function is much smaller than the ones obtained by linear interpolations of the values at the grid points. We also show that the fuzzy rule table in the fuzzy system representation of the bicubic spline function can be viewed as a gray scale image. Hence, the fuzzy rules provide a visual representation of the functions of two variables where the contours of different levels for the function are shown in different gray scale levels

키워드

참고문헌

  1. R.L. Burden, J.D. Faires and A.C. Reynolds, NumericaI Anatysis, Prindle, Weber & Schmidt, pp. 508-519, 1978
  2. C.F. Gerald and P.O. Wheatley, Applied NumericaI Analysis, Addison-Wesley Pub. Co. pp. 544-558, 1989
  3. A. Shmilovici and O. Maimon, 'On the solution of differential equations with fuzzy spline wavelets', Fuzzy Sets and Systems, Vol. 96, pp. 77-99, 1999
  4. A. Shmilovici and O. Maimon, 'The fuzzy rule-basesolution of differential equations', Information Sciences, Vol. 92, pp. 233-254, 1996 https://doi.org/10.1016/0020-0255(96)00075-8
  5. B.S. Moon, et al., 'Solution of Dirichlet boundaryproblem for the Poisson equation based on a fuzzysystem', Computational Intelligent Systems for AppHedResearch, Proc. of 5th International FLINS Conference, pp. 58-65, 2002
  6. B. S. Moon, et al., 'A fuzzy system representation offunctions of two variables and its application to grayscale images', J. Korea Fuzzy Logic and Intelligent Systems Soc., Vol. 11 No.7 pp. 569- 573, 2001
  7. Byung Soo Moon, 'A practical algorithm for representingpolynomials of two variables by fuzzy systems withaccuracy 0($h^4$)', Fuzzy Sets and Systems Vol.119, No.2, 135-141, 2001
  8. B. Kosko, 'Fuzzy systems as universal approximators', IEEE Trans. on Computers, Vol. 43, No.ll, p.1329-1333, 1994 https://doi.org/10.1109/12.324566