“…Hère iï is the Heaviside graph and c is a strictly increasing Lipschitz continuous function. It is well-known that there is a unique solution u (physically, the température) ; moreover it has the global regularity properties [11,17,18,19,23,31] : assume u 0 := J~1(y o ) e C oa (Q) and ƒ e C 04 (R), then (4 * 2) we C°(ë) n L°°(0, T\H\Q)) n H^O, T; L 2 (Q)).…”