Persistent Application Systems (PASs) are of increasing social and economic importance. They have the potential to be long-lived, concurrently accessed and consist of large bodies of data and programs. Typical examples of PASs are CAD/CAM systems, office automation, CASE tools, software engineering environments and patient-care support systems in hospitals. Orthogonally persistent object system...

In 1957, Chandler Davis proved that unitarily invariant convex functions on the space of hermitian matrices are precisely those which are convex and symmetrically invariant on the set of diagonal matrices. We give a simple perturbation theoretic proof of this result. (Davis’ argument was also very short, though based on completely different ideas). Consider an orthogonally invariant function f ...

In [11], Köstler and Speicher showed that de Finetti’s theorem on exchangeable sequences has a free analogue if one replaces exchangeability by the stronger condition of invariance of the joint distribution under quantum permutations. In this paper we study sequences of noncommutative random variables whose joint distribution is invariant under quantum orthogonal transformations. We prove a fre...

Orthogonally persistent Java combines the power of abstraction over persistence with Java’s rich programming environment. In this paper we report our experience in designing and implementing orthogonally persistent Java. Our design approach is anchored by the view that any system that brings together Java and orthogonal persistence should as far as possible avoid diluting the strengths of Java ...

Let $M$ and $N$ be Archimedean vector lattices. We introduce orthogonally additive band operators inverse from to examine their properties. investigate the relationship between disjointness preserving show that under some assumptions on lattices or $N$, these two classes are same. By using this relation, we if ${\mu }$ is a bijective operator (resp. operator) into then }^{-1}$:$N$${\rightarrow}...

As a step towards characterizing the graphs of orthogonally convex polyhedra, we show that for any simple orthogonally convex polyhedron there is an orthoball that is equivalent in the sense that it has the same graph and the same face normals. An orthoball is a simple orthogonally convex polyhedron with a point inside that sees the whole interior (informally, it is “round”). The consequence fo...