Current-day crawlers retrieve content from the publicly indexable Web, i.e., the set of web pages reachable purely by following hypertext links, ignoring search forms and pages that require authorization or prior registration. In particular, they ignore the tremendous amount of high quality content “hidden” behind search forms, in large searchable electronic databases. Our work provides a frame...

Currently, there is much interest in the development of geometric integrators, which retain analogues of geometric properties of an approximated system. This paper provides a means of ensuring that finite difference schemes accurately mirror global properties of approximated systems. To this end, we introduce a cohomology theory for lattice varieties, on which finite difference schemes and othe...

Of the six structures presented here, five involve clearly defined hydrophilic layers built up from classical hydrogen bonding systems. Of three solvent-free structures, 2,4and 3,5-dichloroanilinium chlorides both form ribbon structures involving annelated R4(8) rings with NH2 donors (two hydrogen atoms from the positively charged NH3 groups) and chloride acceptors. The ribbons are linked by we...

In this paper, we develop a model for uncertain default reasoning. It has the following characteristics: 1) basic uncertainty is estimated in terms of an interval number, and so the ignorance about knowledge can be coped with; 2) it has some capability of handling commonsense knowledge in forms of default rules with uncertainty, in which Reiter's system is a special case; and 3) the propagation...

Current-day crawlers retrieve content from the publicly indexable Web, i.e., the set of web pages reachable purely by following hypertext links, ignoring search forms and pages that require authorization or prior registration. In particular, they ignore the tremendous amount of high quality content “hidden” behind search forms, in large searchable electronic databases. Our work provides a frame...

For d-dimensional exponential Lévy models, variational formulations of the Kolmogorov equations arising in asset pricing are derived. Well-posedness of these equations is verified. Particular attention is paid to pure jump, d-variate Lévy processes built from parametric, copula dependence models in their jump structure. The domains of the associated Dirichlet forms are shown to be certain aniso...

We present gauge invariant, self adjoint Einstein operators for mixed symmetry higher spin theories. The result applies to multi-forms, multi-symmetric forms and mixed antisymmetric and symmetric multiforms. It also yields explicit action principles for these theories in terms of their minimal covariant field content. For known cases, these actions imply the mixed symmetry equations of motion o...

When extending a scientific knowledge base with new information, particularly information presented in natural language, it is important that the information be encoded in a form that is compatible with the existing knowledge base. Hand built systems for semantic interpretation and knowledge integration can suffer from brittleness. Methods for learning semantic interpretation and integration ex...