The expressive power of the family wILOG of relational query languages is investi gated The languages are rule based with value invention and strati ed negation The semantics for value invention is based on Skolem functor terms We study a hierarchy of languages based on the number of strata allowed in programs We rst show that in presence of value invention the class of strati ed programs made ...

The expressive power of the family wILOG(:) of relational query languages is investigated. The languages are rule based, with value invention and strati ed negation. The semantics for value invention is based on Skolem functor terms. We study a hierarchy of languages based on the number of strata allowed in programs. We rst show that, in presence of value invention, the class of strati ed progr...

Stiffly accurate implicit Runge–Kutta methods are studied for the time discretisation of nonlinear first-order evolution equations. The equation is supposed to be governed by a time-dependent hemicontinuous operator that is (up to a shift) monotone and coercive, and fulfills a certain growth condition. It is proven that the piecewise constant as well as the piecewise linear interpolant of the t...

in this article, we have shown, for the add-point monad t, thepartial morphism category set*is isomorphic to the kleisli category sett. alsowe have proved that the category, sett, of t-algebras is isomorphic to thecategory set of pointed sets. finally we have established commutative squaresinvolving these categories.

In this article, we have shown, for the add-point monad T, thepartial morphism category Set*is isomorphic to the Kleisli category SetT. Alsowe have proved that the category, SetT, of T-algebras is isomorphic to thecategory Set of pointed sets. Finally we have established commutative squaresinvolving these categories.

Existence of solutions for a class of doubly nonlinear evolution equations of second order is proven by studying a full discretisation. The discretisation combines a time stepping on a nonuniform time grid, which generalises the well-known Störmer–Verlet scheme, with an internal approximation scheme. The linear operator acting on the zero-order term is supposed to induce an inner product, where...

Let E C X be the finite-dimensional subspace spanned by xi, ..., xm. Now, for y E Y and variable x e E, y(x) is a continuous linear functional on E which we denote by y'. Thus, there is defined in a natural way a function f'(x) with domain (E n B) and range in E*, the conjugate space of E. The domain contains and surrounds densely every point of E n K(D), hence every point of K(E n D). It is ea...