We consider two-phase Navier–Stokes flow with a Boussinesq–Scriven surface fluid. In such a fluid the rheological behaviour at the interface includes surface viscosity effects, in addition to the classical surface tension effects. We introduce and analyze parametric finite element approximations, and show, in particular, stability results for semi-discrete versions of the methods, by demonstrat...

Essentially, a Petri net controlled grammar is a context-free grammar equipped with a Petri net and a function which maps transitions of the net to rules of the grammar. The language consists of all terminal words that can be obtained by applying of a sequence of productions which is the image of an occurrence sequence of the Petri net under the function. We study the generative power of such g...

In this paper, a system composed of two pairs of two-level atoms and a multimode-vacuum field is considered. In our model, either pair contains two atoms that are assumed to be set close. We propose a disentanglement-free state of the two pairs of two-level atoms. It is remarkable that when the two pairs, initially in such a state, fly apart an arbitrary distance, the state will undergo no deco...

The XML community generally takes trees and hedges as the model for XML document instances and element content. In contrast, Berstel and Boasson have discussed XML documents in the framework of extended context-free grammar, modeling XML documents as Dyck strings and schemas as balanced grammars. How can these two models be brought closer together? We examine the close relatioship between Dyck ...

For implementation&#10 of the free surface boundary condition, a new subroutine has been introduced to an existing steady 3-D body fitted code. This code was previously written for steady flow simulation in closed ducts. The algorithm used in this subroutine reduces the instability problem according to the free surface wave generation. For code validation, it was applied to two different open c...

For implementation of the free surface boundary condition, a new subroutine has been introduced to an existing steady 3-D body fitted code. This code was previously written for steady flow simulation in closed ducts. The algorithm used in this subroutine reduces the instability problem according to the free surface wave generation. For code validation, it was applied to two different open cha...