The study aimed to optimize the Plasma Beam Polishing process for 316L stainless steel components to reduce anisotropy and poor surface roughness using statistical analysis. An experimental design investigated the impacts of managing factors on surface roughness, with scanning speed having the ultimate impact, followed by beam power and energy density. For lower values of plasma energy density and scanning speed, and a focal location without changes on the metal surface, there was a strong tendency for the estimated Ra to drop with increasing laser power. The process parameters were changed throughout a broad range of values, making it challenging to model the dependent variable across the whole range of experimental trials. The study supports the potential of PBP as a post-processing method for additive manufacturing components.

The 15-winding and 3-column autotransformer supplying an 18-pulse rectifier circuit was developed. Presented methods can be used also for the autotransformers of other topologies supplying different kinds of converters. Presented methods make it possible to exactly calculate main and leakage inductances of the multi-winding autotransformer. The presented analysis of the eigenvalues and eigenvectors of the inductance matrix makes it possible to identify the influence nature of individual modes on the inductance matrix, and to compare the calculation results obtained using the presented methods. Frequency dependence of autotransformer parameters was shown. Also modes of the impedance matrix of the multi-winding autotransformer was investigated, this made it possible to identify the influence nature of individual modes on the inductance matrix. Using presented methods one can exactly calculate main and leakage inductances of the autotransformer. Thanks to this, one can design in optimal way autotransformers for supplying, for example, rectifier circuits, THD coefficients. The results of the measurements and simulations were also shortly presented at the end of the article.

The authors analyze the new book The place of the Macedonian phonetics within the Slavic and Balkan linguistic area from Irena Sawicka and Anna Cychnerska. The book is trying to shed new light on the place of Macedonian phonetics regarding its Slavic heritage and also regarding the contact changes that appeared during development of the Macedonian language in the Balkan linguistic league. Their research is conducted on Macedonian dialects represented in Common linguistic atlas (OLA) and in Phonological bases of the Macedonian dialects from B. Vidoeski. In their book, Sawicka and Cychnerska state that they use diachronic data, but their main goal is to present selected synchronic features from the Macedonian phonetics. They explain most of the phonetic features in Macedonian from an areal-typological aspect with special emphasis on the Balkan convergences. The authors of the book state that the Macedonian phonetic should be included in southwest type of Slavic phonetics. They conclude that the modern form of Macedonian phonetic, to large extent, was influenced by areal position of the Macedonian language and to its development in the Balkan multilingual territory.