Variational principle for the asymptotic speed of fronts of the density-dependent diffusion-reaction equation.
نویسندگان
چکیده
We show that the minimal speed for the existence of monotonic fronts of the equation ut = (u )xx + f(u) with f(0) = f(1) = 0, m > 1 and f > 0 in (0, 1), derives from a variational principle. The variational principle allows to calculate, in principle, the exact speed for general f . The case m = 1 when f (0) = 0 is included as an extension of the results.
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ورودعنوان ژورنال:
- Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics
دوره 52 3 شماره
صفحات -
تاریخ انتشار 1995