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M. M. Parsa, K. Sayevand, H. Jafari, I. Masti / IJOCTA, Vol.15, No.2, pp.225-244 (2025)
                    Table 1. The maximum numerical errors and computational orders of Example 1 where
                    M x = 100 and different N t and β values

                                     N t   β = 0.1  Order  β = 0.5  Order  β = 0.9  Order
                                     32  3.5436 × 10 −3  -  4.7725 × 10 −4  -  8.4154 × 10 −5  -
                                     64  7.3850 × 10 −3  1.32  7.1826 × 10 −5  1.38  1.9827 × 10 −5  1.59
                                     128  5.9453 × 10 −4  1.33  5.9920 × 10 −6  1.39  3.1951 × 10 −6  1.61
                                     256  9.1414 × 10 −5  1.35  2.0114 × 10 −6  1.41  6.4299 × 10 −7  1.63
                    Table 2. The numerical results for Example 1 where β = 0.7 and M x = 100 and different
                    values of ∆t

                                          Present method       Method presented in 36
                                     ∆t       L ∞     Order          L ∞        Order
                                      1    3.7264 × 10 −4  -        0.0037        -
                                     10
                                      1    2.1640 × 10 −5  1.43     0.0015      1.27
                                     20
                                      1    4.4052 × 10 −5  1.41   6.2714 × 10 −4  1.29
                                     40
                                      1    5.7631 × 10 −6  1.47   2.5377 × 10 −4  1.31
                                     80
                    Table 3. The numerical results for Example 1 where β = 0.7 and M x = 150 and different
                    values of ∆t


                                          Present method       Method presented in 30
                                     ∆t       L ∞     Order          L ∞        Order
                                      1    4.7641 × 10 −5  -      5.821 × 10 −3   -
                                     10
                                      1    8.9002 × 10 −5  1.48   2.304 × 10 −3  1.33
                                     20
                                      1    3.1383 × 10 −6  1.51   9.081 × 10 −4  1.34
                                     40
                                      1    9.5381 × 10 −7  1.52   3.572 × 10 −4  1.34
                                     80


                               β = 0.5
                       1                                                1.5     β = 0.9
                      u(x,t) 0.5                                        u(x,t)  1
                       0                                                0.5
                      -0.5                                               0
                       1                                                 1
                                                 1                                                1
                            0.5            0.6  0.8                          0.5             0.6  0.8
                                         0.4                                              0.4
                                      0.2                                               0.2
                                  0                                                0  0
                             t     0     x                                     t          x
            Figure 2. The approximate solutions of Example 1  Figure 4. The approximate solutions of Example 1
            for β = 0.5 and M x = N t = 100                   for β = 0.9 and M x = N t = 100

                                                              Example 2. Consider the following TFB-S
                                                              model: 37


                                                                              2
                                                                β
                                                               ∂ u(x, t)    ∂ u(x, t)    ∂u(x, t)
                                                                        = A          + B         − Cu(x, t),
                                                                  ∂t β         ∂x 2         ∂x
                                                                                                        (139)
                                                                  where (x, t) ∈ (0, X) × (0, T), r = 0.04, σ =
                       0.6     β = 0.7                                 σ 2          σ 2
                                                              0.3, A =   , B = r −     and C = r, u(0, t) = 0,
                      u(x,t) 0.4                                        2       −rt  2
                       0.2                                    u(X, t) = X − Ee     , u(x, 0) = max(x − E, 0)
                                                              where X = 40, T = 1 and E = 10. In this case,
                       0
                       1
                                                 1            the exact solution of the equation is not available.
                                              0.8
                            0.5            0.6
                                         0.4
                                      0.2
                             t    0  0   x
                                                                  To measure the accuracy of the method, we
            Figure 3. The approximate solutions of Example 1  compute the errors norm (e  N t  ) and computa-
                                                                                          M x
            for β = 0.7 and M x = N t = 100                   tional orders (R N t  ):
                                                                             M x
                                                           238
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