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A second order difference scheme for time fractional diffusion equation with generalized memory kernel

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 نشر من قبل Anatoly Alikhanov A.
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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In the current work we build a difference analog of the Caputo fractional derivative with generalized memory kernel ($_lambda$L2-1$_sigma$ formula). The fundamental features of this difference operator are studied and on its ground some difference schemes generating approximations of the second order in time for the generalized time-fractional diffusion equation with variable coefficients are worked out. We have proved stability and convergence of the given schemes in the grid $L_2$ - norm with the rate equal to the order of the approximation error. The achieved results are supported by the numerical computations performed for some test problems.

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