Analyse multiéchelle Boundary value problems for second-order elliptic equations Controllability Controllability, observability, and system structure Dependence of solutions on initial and boundary data, parameters Differential equations, Partial Elliptic equations and systems Équations aux dérivées partielles Finite difference methods Fluid mechanics Foundations, constitutive equations, rheology Hyperbolic equations and systems Image processing Initial-boundary value problems for higher-order parabolic equations Inverse problems Laplacian operator, reduced wave equation (Helmholtz equation), Poisson equation Liquid crystals Mathematics Mathématiques Miscellaneous topics Multiscale modeling Numerical analysis Parabolic equations and systems Partial differential equations Partial differential equations, initial value and time-dependent initial-boundary value problems Qualitative properties of solutions Systems theory; control Traitement d'images Wave equation