Characterization, definability and separation via saturated models

Characterization, definability and separation via saturated models

Three important results about the expressivity of a modal logic L are the Characterization Theorem (that identifies a modal logic L as a fragment of a better known logic), the Definability theorem (that provides conditions under which a class of L-models can be defined by a formula or a set of formulas of L), and the Separation Theorem (that provides conditions under which two disjoint classes ...

On Characterization, Definability and ω-Saturated Models

Two important classic results about modal expressivity are the Characterization and Definability theorems. We develop a general theory for modal logics below first order (in terms of expressivity) which exposes the following result: Characterization and Definability theorems hold for every (reasonable) modal logic whose ω-saturated models have the Hennessy-Milner property. The results are prese...

Pro-Aperiodic Monoids via Saturated Models

We apply Stone duality and model theory to study the structure theory of free pro-aperiodic monoids. Stone duality implies that elements of the free pro-aperiodic monoid may be viewed as elementary equivalence classes of pseudofinite words. Model theory provides us with saturated words in each such class, i.e., words in which all possible factorizations are realized. We give several application...

Preparation and characterization of polyethylene/ glass fiber composite membrane prepared via thermally induced phase separation method

Grinded glass fiber (GGF) embedded high density polyethylene (HDPE) membranes were prepared via thermally induced phase separation method. FESEM images showed that all the membranes had leafy structure, indicating a solid-liquid mechanism during phase separation. The results of EDX and TGA analyses confirmed that the fibers were dispersed in the HDPE matrix uniformly. Normalized water flux of t...

Relative Definability and Models of Unary PCF