Interval Analysis of the Fuzzy-Random Heat Conduction in the Composite Tubes

During the analysis of stability heat conduction in the composite tubes and when the temperature boundary conditions were the random conditions, first equations of the mean values and variances of the random thermal function were transformed. Secondly when the heat conduct parameters were the fuzzy numbers and the temperature boundary conditions were the random numbers, interval equations of the heat conduction were presented. Thirdly compared with the interval results between in the interval analysis and in the confidence interval, the result in the interval analysis is larger than that in the confidence interval. Moreover the error expecting equation was presented. Finally, with upper (lower) approximation in rough set theory, a new method of the interval analysis to deal with the stability heat conduction was presented.