On the State Complexity of Partial Derivative Automata For Regular Expressions with Intersection

Extended regular expressions (with complement and intersection) are used in many applications due to their succinctness. In particular, regular expressions extended with intersection only (also called semi-extended) can already be exponentially smaller than standard regular expressions or equivalent nondeterministic finite automata (NFA). For practical purposes it is important to study the average behaviour of conversions between these models. In this paper, we focus on the conversion of regu...

Freixo de Numao Au-W deposit, Northern Portugal: ore features and mineralization controls

The Freixo de Numao Au-W deposit is located in Vila Nova de Foz Coe region, northern Portugal. Mineralization is hosted in greenschist-facies metasedimentary rocks with lower-Cambrian age. The mineralized structures are subvertical and trend N10 degrees - 40 degrees E, crossing-cut bedding and/or regional foliation, and are post-peak of regional metamorphism. Quartz-sulfide veins and visible hydrothermal alteration characterize this mineralization in the field. The quartz veins record two mai...

Deciding Synchronous Kleene Algebra with Derivatives

Synchronous Kleene algebra (SKA) is a decidable framework that combines Kleene algebra (KA) with a synchrony model of concurrency. Elements of SKA can be seen as processes taking place within a fixed discrete time frame and that, at each time step, may execute one or more basic actions or then come to a halt. The synchronous Kleene algebra with tests (SKAT) combines SKA with a Boolean algebra. Both algebras were introduced by Prisacariu, who proved the decidability of the equational theory, t...

DIVERT for realistic simulation of heterogeneous vehicular networks

Simulation of vehicular networks has been extensively studied in the last few years. In order to have an holistic view of the network functioning, communications and vehicle mobility aspects should be modeled in detail and fully integrated. This article presents a tool for simulating heterogeneous vehicular networks. The existing microscopic traffic simulator, DIVERT, has been extended by adding NS-3 support resulting in a very tightly integrated simulator. The feasibility of the approach has...