We investigate the Constraint Satisfaction Problem (CSP) over templates with a group structure, and algorithms solving CSP that are equivariant, i.e. invariant under a natural group action induced by a template. Our main result is a method of proving the implication: if CSP over a coset template T is solvable by an equivariant algorithm then T is 2-Helly (or equivalently, has a majority polymor...

In a pervasive computing environment, energy is one of the critical restriction factors of embedded devices. Dynamic voltage scaling (DVS) has been proven to be an effective method for reducing energy consumption of processors. This paper proposes an energy-saving algorithm under the fixed priority multi-subtask model. This algorithm includes two parts: first, it exploits the relationship among...

We continue with the task of obtaining a unifying view of process semantics by considering in this case the logical characterization of the semantics. We start by considering the classic linear timebranching time spectrum developed by R.J. van Glabbeek. He provided a logical characterization of most of the semantics in his spectrum but, without following a unique pattern. In this paper, we pres...

This paper studies the descriptional complexity of multi-parallel grammars with respect to the number of nonterminals and selectors, and the length of these selectors. As a result, it proves that every recursively enumerable language is generated by a multi-parallel grammar with no more than seven nonterminals and four selectors of length five.