“Pra lá e pra cá”

Human PRA PRA PRA PRA PRA

This paper proposes the concept of Co-Habited Mixed Reality, and argues how it serves as a basis for large-scale social interaction systems and communityware. The technology that it implies is aimed at focusing a large potential for interaction such that eeectiveness of participation to large scale events is enhanced. We illustrate the idea with scenarios from an ongoing project (COMRIS: co-hab...

Interpretability in PRA

In this paper we study IL(PRA), the interpretability logic of PRA. As PRA is neither an essentially reflexive theory nor finitely axiomatizable, the two known arithmetical completeness results do not apply to PRA: IL(PRA) is not ILM or ILP. IL(PRA) does of course contain all the principles known to be part of IL(All), the interpretability logic of the principles common to all reasonable arithme...

Using Standard Pra S

Although maximal localization is a basic notion in the consideration of phase-space representations of fields, it has not yet been pursued for general wave fields. We develop measures of spatial and directional spreads for nonparaxial waves in free space. These measures are invariant under translation and rotation and are shown to reduce to the conventional ones when applied to paraxial fields....

Using Standard Pra S

Theoretical and numerical analyses of waveguide branches in a photonic crystal are presented. Conditions for perfect transmission and zero reflection are discussed. Based upon these conditions, numerical simulations of electromagnetic-wave propagation in photonic crystals are performed to identify structures with near-complete transmission. © 2001 Optical Society of America OCIS codes: 130.1750...

Theory and Pra ti e of Logi Programming