We review several approaches for characterizing chaotic systems in view of their comparison and discuss the advantages and limits of these approaches in the context of specific application classes. Precise aims of the characterization are stated and the demands in various applications analyzed. We specifically deal with methods of determining features of the attractors that are suitable in engineering and medical applications, such as control, measurement, and pattern recognition, based on chaotic dynamics.

The SRoL Web-based spoken language repository and tool collection includes thousands of voice recordings grouped on sections like "Basic sounds of the Romanian language", "Emotional voices", "Specific language processes", "Pathological voices", "Comparison of natural and synthetic speech", "Gnathophonics and gnathosonics". The recordings are annotated and documented according to proprietary methodology and protocols. Moreover, we included on the site extended documentation on the Romanian language, on speech technology, and on tools, produced by the SRoL team, for voice analysis. The resources are a part of the CLARIN European Network for Language Resources. The resources and tools are useful in virtual learning for phonetics of the Romanian language, speech technology, and medical subjects related to voice. We report on several applications in language learning and voice technology classes. Here, we emphasize the utilization of the SRoL resources in education for medicine and speech rehabilitation.

Based on a movement sensor introduced in a companion paper, a system for monitoring the movements of a person is presented. The system comprises a set of capacitive sensors printed on the clothes and the capacitance measuring circuits. The network is described and experimental results are illustrated and discussed.

The article extends the theoretical and applicative analysis of Zipf’s law. We are concerned with a set of properties of Zipf’s law that derive directly from the power law expression and from the discrete nature of the objects to which the law is applied, when the objects are words, lemmas, and the like. We also search for variations of Zipf’s law that can help explain the noisy results empirically reported in the literature and the departures of the empirically obtained nonlinear graph from the theoretical linear one, with the variants analyzed differing from Mandelbrot and lognormal distributions. A problem of interest that we deal with is that of mixtures of populations obeying Zipf’s law. The last problem has relevance in the analysis of texts with words with various etymologies. Computational aspects are also addressed.