Surface mesh generation through Delaunay refinement is considered as a relevant alternative to the common marching cubes algorithm. One distinctive feature lies into the fact that it interleaves shape probing (through intersection with Voronoi edges) with refinement. The current implementations require seeding the refinement procedure for each connected component so as to guarantee that all com...

In the impact-echo method, the presence and the locations of defects in concrete are estimated from identifying peak frequencies in the frequency spectra, which are responsible for the resonance due to time-of-flight from the defects. In practical applications, however, spectra obtained include so many peak frequencies that it is fairly difficult to identify the defects correctly. SIBIE (Stack ...

This work examines the problem of sequential change detection in the constant drift of a Brownian motion in the case of multiple alternatives. As a performance measure an extended Lorden’s criterion is proposed. When the possible drifts, assumed after the change, have the same sign, the CUSUM rule designed to detect the smallest in absolute value drift, is proven to be the optimum. If the drift...

Weakly recognizing morphisms from free semigroups onto finite semigroups are a classical way for defining the class of ω-regular languages, i.e., a set of infinite words is weakly recognizable by such a morphism if and only if it is accepted by some Büchi automaton. We consider the descriptional complexity of various constructions for weakly recognizing morphisms. This includes the conversion f...

The communication structure of parallel communicating grammar systems (PCGS) considered as the descriptional complexity of PCGS is investigated here. The aim of the paper is to compare computational power of PCGS’s with respect to their communication structure. Investigating the generation of the languages over one-letter alphabet the communication structures dags(directed acyclic graphs) and c...

We prove that the set of properties describable by a uniform sequence of rst-order sentences using at most k + 1 distinct variables is exactly equal to the set of properties checkable by a Turing machine in DSPACEn k ] (where n is the size of the universe). This set is also equal to the set of properties describable using an iterative deenition for a nite set of relations of arity k. This is a ...