On closedness ofC- andC∗-embeddings

On Proving Communication Closedness of Distributed Layers

The notion of communication closed layer has been introduced as a way to define structured composition of distributed sy~tems. An interesting question is how to verify the closedness of a layer. We formulate a proof rule proving closed ness of a distributed layer. The rule is developed as an extension of the Apt. Francez and de Roever proof system for CSP. The extension is proved to be sound an...

On Closedness of Orbits of Algebraic Groups

LωH-closedness in Lω-spaces

In this paper, the concepts of LωH-sets and LωH-closed spaces are proposed in Lω-spaces by means of (αω)−-remote neighborhood family. The characterizations of LωH-sets and LωH-closed spaces are systematically discussed. Some important properties of LωH-closed spaces, such as the LωH-closed spaces is ω-regular closed hereditary, arbitrarily multiplicative and preserving invariance under almost (...

Closedness properties in ex-identification

In this paper we investigate in which cases unions of identi$able classes are also necessarily identi$able. We consider identi$cation in the limit with bounds on mindchanges and anomalies. Though not closed under the set union, these identi$cation types still have features resembling closedness. For each of them we $nd n such that (1) if every union of n − 1 classes out of U1; : : : ; Un is ide...

Feature Construction Based on Closedness Properties Is Not That Simple

Feature construction has been studied extensively, including for 0/1 data samples. Given the recent breakthrough in closedness-related constraint-based mining, we are considering its impact on feature construction for classification tasks. We investigate the use of condensed representations of frequent itemsets (closure equivalence classes) as new features. These itemset types have been propose...