In this paper we consider quasi-interpolatory spline operators that satisfy some interpolation conditions. We give some applications of these operators constructing approximating integral operators and numerically solving Volterra integral equations of the second kind. We prove convergence results for the constructed methods and we perform numerical examples and comparisons with other spline me...

Based on H-Galerkin mixed finite element method with nonconforming quasi-Wilson element, a numerical approximate scheme is established for pseudo-hyperbolic equations under arbitrary quadrilateral meshes. The corresponding optimal order error estimate is derived by the interpolation technique instead of the generalized elliptic projection which is necessary for classical error estimates of fini...

Approximation orders of shift-invariant subspaces of L p (IR d), 2 p 1, generated by the shifts of one compactly supported function are considered. In that course, explicit approximation maps are constructed. The approach avoids quasi-interpolation and applies to stationary and non-stationary reenements. The general results are specialized to box spline spaces, to obtain new results on their ap...

This article provides a glimpse at Nigel Kalton’s contribution to interpolation of Banach spaces. Examples and concepts which look unrelated at first sight, such as quasi-linear maps, non-trivial twisted sums and interpolating operators are shown to be relevant to the same theory.