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Interaction of Turing and Hopf Modes in the Superdiffusive Brusselator Model Near a Codimension Two Bifurcation Point

J. C. Tzou, A. Bayliss, B.J. Matkowsky, V.A. Volpert (2010)

Mathematical Modelling of Natural Phenomena

Spatiotemporal patterns near a codimension-2 Turing-Hopf point of the one-dimensional superdiffusive Brusselator model are analyzed. The superdiffusive Brusselator model differs from its regular counterpart in that the Laplacian operator of the regular model is replaced by ∂α/∂|ξ|α, 1 < α < 2, an integro-differential operator that reflects the nonlocal behavior of superdiffusion. The order of the operator, α, is a measure of the rate of ...

Interfaces in solutions of diffusion-absorption equations.

Sergei Shmarev (2002)

RACSAM

We study the properties of interfaces in solutions of the Cauchy problem for the nonlinear degenerate parabolic equation ut = Δum - up in Rn x (0,T] with the parameters m &gt; 1, p &gt; 0 satisfying the condition m + p ≥ 2. We show that the velocity of the interface Γ(t) = ∂{supp u(x,t)} is given by the formula v = [ -m / (m-1) ∇um-1 + ∇Π ]|Γ(t) where Π is the solution of the degenerate elliptic equation div (u∇Π) + up = 0, Π = 0 on Γ(t). We give explicit formulas which represent the interface...

Interior regularity for weak solutions of ultraparabolic equations in divergence form with discontinuous coefficients

Maria Manfredini, Sergio Polidoro (1998)

Bollettino dell'Unione Matematica Italiana

Abbiamo considerato il problema della regolarità interna delle soluzioni deboli della seguente equazione differenziale i , j = 1 m 0 x i a i , j x , t x j u + i , j = 1 N b i , j x i x j u - t u = j = 1 m 0 x j F j x , t , dove x , t R N + 1 , 0 < m 0 N ed F j L loc p R N + 1 per j = 1 , , m 0 . I nostri principali risultati sono una stima a priori interna del tipo j = 1 m 0 x j u p c j = 1 m 0 F j p + u p , e la regolarità hölderiana di u . La stima a priori delle derivate viene ottenuta utilizzando una tecnica analoga a quella introdotta da Chiarenza, Frasca e Longo in [3], per gli operatori ellittici in forma di non divergenza, supponendo che i coefficienti a i , j verifichino una condizione...

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