Weighted pseudo-almost periodic solutions for some neutral partial functional differential equations.
Weighted -asymptotically -periodic solutions of a class of fractional differential equations.
Well posedness and control of semilinear wave equations with iterated logarithms
Motivated by a classical work of Erdős we give rather precise necessary and sufficient growth conditions on the nonlinearity in a semilinear wave equation in order to have global existence for all initial data. Then we improve some former exact controllability theorems of Imanuvilov and Zuazua.
Well posedness for evolution inclusions.
Well-posedness of abstract Cauchy problems.
Well-posedness of the boundary value problem for parabolic equations in difference analogues of spaces of smooth functions.
Well-posedness of the difference schemes of the high order of accuracy for elliptic equations.
Weyl-Titchmarsh theory for Hamiltonian dynamic systems.
Weyl-Titchmarsh theory for time scale symplectic systems on half line.
What do Multistep Methods Approximate?
When singular points determine quadratic systems.
When unit groups of continuous inverse algebras are regular Lie groups
It is a basic fact in infinite-dimensional Lie theory that the unit group of a continuous inverse algebra A is a Lie group. We describe criteria ensuring that the Lie group is regular in Milnor’s sense. Notably, is regular if A is Mackey-complete and locally m-convex.
Wiener amalgam spaces for the fundamental identity of Gabor analysis.
In the last decade it has become clear that one of the central themes within Gabor analysis (with respect to general time-frequency lattices) is a duality theory for Gabor frames, including the Wexler-Raz biorthogonality condition, the Ron-Shen duality principle and the Janssen representation of a Gabor frame operator. All these results are closely connected with the so-called Fundamental Identity of Gabor Analysis, which we derive from an application of Poisson's summation formula for the symplectic...
Wirtinger inequality and nonlinear differential systems
Picone identity for a class of nonlinear differential equations is established and various qualitative results (such as Wirtinger-type inequality and the existence of zeros of first components of solutions) are obtained with the help of this new formula.
WKB estimates for linear dynamic systems on time scales.
Wrapped eigenstructure of chaos
Wronskians and subspaces of certain fourth order differential equations.