The abrupt disappearance of the bees that pollinate crops is a significant subject of recent study. One theory points to the development of telecommunications technology and an increasing number of electromagnetic field sources as a possible cause of the phenomenon.This paper presents the results of preliminary studies of honeybee exposure to extremely low frequency electromagnetic field (50 Hz; 1 mT, 7 mT) Streszczenie. Nagłe znikanie pszczół, które zapylają uprawy, jest jednym z istotnych tematów ostatnich badań. Jedna z teorii wskazuje na rozwój telekomunikacji i zwiększenie liczby źródeł pola elektromagnetycznego jako możliwą przyczynę tego zjawiska. Artykuł prezentuje wyniki wstępnych badań nad ekspozycję pszczół miodnych na pole elektromagnetyczne o wyjątkowo niskiej częstotliwości (50 Hz; 1 mT 7 mT) (Pola elektromagnetyczne i zespół masowego ginięcia pszczoły miodnej).

Induction motors with two degrees of freedom are unconventional drives offering broader possibilities of different movements than traditional drives. There is general opinion that construction of a machine with 2 degrees of freedom (2DoF machine) is much more complicated and expensive than a machine with one degree of freedom. In the paper the authors show that it is possible to construct in easy way (even in an university laboratory workshop) a 2DoF 2-module induction motor using components of a factory-manufactured 3-phase squirrel-cage motor. The presented solution is one of many possibilities and should be treated as the exemplary case elaborated and tested at the Silesian University of Technology in Gliwice.

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During a serious underground incident the most important things are the lives of miners and the time necessary for the rescue team to find victims of the accident. The paper presents the concept of a new drilling system that uses torsional vibrations in the drilling process. In the article formulating mathematical models of a drilling rig is one of the tasks of the INDIRES (INformation Driven Incident RESponse) project implemented as a part of the European Research Fund for Coal and Steel. The INDIRES project is dedicated to the task of conducting a rescue operation after accidents in mines.