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   <dc:title>The mesa problem: diffusion patterns for ut=∇⋅(um∇u) as m→+∞ .</dc:title>
   <dc:creator>Elliot, C. M.</dc:creator>
   <dc:creator>Herrero, Miguel A.</dc:creator>
   <dc:creator>King, J. R.</dc:creator>
   <dc:creator>Ockendon, J.R.</dc:creator>
   <dc:subject>517.9</dc:subject>
   <dc:subject>517.956.4</dc:subject>
   <dc:subject>Porous-medium equation</dc:subject>
   <dc:subject>initial data</dc:subject>
   <dc:subject>spatially independent</dc:subject>
   <dc:subject>initial value</dc:subject>
   <dc:subject>free boundary</dc:subject>
   <dc:subject>Stefan problem</dc:subject>
   <dc:subject>variational inequalities</dc:subject>
   <dc:subject>singular-perturbation</dc:subject>
   <dc:subject>structure of the transition region</dc:subject>
   <dc:subject>Ecuaciones diferenciales</dc:subject>
   <dc:subject>1202.07 Ecuaciones en Diferencias</dc:subject>
   <dc:description>In this paper we consider the limit m→+∞ of solutions of the porous-medium equation ut = ∇•(um∇u)(xεRN), with N > 1. We conjecture that, for initial data with a unique maximum, the evolution is characterized by the onset of a ‘mesa’ region, in which the solution is nearly spatially independent, surrounded by a region in which u is nearly equal to its initial value. The transition between these regions occurs near a surface which is identified with the free boundary in a certain Stefan problem which can be studied using variational inequalities. Moreover, singular-perturbation theory can be used to describe the structure of the transition region.</dc:description>
   <dc:description>Depto. de Análisis Matemático y Matemática Aplicada</dc:description>
   <dc:description>Fac. de Ciencias Matemáticas</dc:description>
   <dc:description>Instituto de Matemática Interdisciplinar (IMI)</dc:description>
   <dc:description>TRUE</dc:description>
   <dc:description>pub</dc:description>
   <dc:date>2023-06-21T02:03:58Z</dc:date>
   <dc:date>2023-06-21T02:03:58Z</dc:date>
   <dc:date>1986</dc:date>
   <dc:type>journal article</dc:type>
   <dc:identifier>https://hdl.handle.net/20.500.14352/64758</dc:identifier>
   <dc:identifier>0272-4960</dc:identifier>
   <dc:identifier>10.1093/imamat/37.2.147</dc:identifier>
   <dc:rights>metadata only access</dc:rights>
   <dc:publisher>Oxford University Press</dc:publisher>
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