In this article results of diagnostic investigations of separately excited DC motor were presented. In diagnostics were applied a Fourier analysis method based on the fast Fourier transform (FFT) and a recognition method using Bayes classifier. In training process a set of the most important frequencies has been determined for which differences of corresponding signals in two states are the largest. Three categories of signals have been recognized in identification process: faultless state, state of the rotor broken one coil and state of the rotor shorted three coils
Cheerleading is a new sport, practiced in 110 nations; since 2016 enjoys provisional Olympic status. Its leaders claim that it is a “happy” sport, but research on its psychological effects is lacking. In this field-study we examined core-affect, positive-affect, and negative-affect in 65 cheerleaders before, during, after, and one-hour after a cheerleading training. Core-affect was more positive during and immediately after training, but it tapered off one hour following the training when feeling states were still more positive than at baseline. Negative-affect declined linearly from baseline to one-hour following training when it became significantly lower than its previous values. Positive-affect showed quadratic dynamics, in parallel with arousal, being higher during and immediately after training than during baseline, or one-hour after training. These results demonstrate for the first time that cheerleading is a “happy” sport, which apart from the skill-development also yields positive psychological emotions both during and after training.
The Bluetooth Low Energy (BLE) MESH network technology gains popularity in low duty IoT systems. Its advantage is a low energy consumption that enables long lifetime of IoT systems. The paper proposes and evaluates new MRT management methods, i.e. exact and heuristic, that improves energy efficiency of BLE MESH network by minimizing the number of active relay nodes. The performed experiments confirm efficiency of the MRT methods resulting in significantly lower energy consumption of BLE MESH network.
Surface phenomena play a major role in metallurgical processes; their operation results, among others, from the surface tension of liquid oxidic systems. One of the methods of determining surface tension of oxidic systems is performing calculations with Butler’s method. Surface tension was calculated for two- and three-component liquid oxidic systems typical of metallurgical processes. The determined dependence of surface tension in FeO-SiO2 at temp. 1773 K and CaO-SiO2 at temp.1873 K showed that with the growing participation of SiO2 surface tension decreased. Analogous calculations were performed for three-component systems: CaO-Al2O3-SiO2 and MnO-Al2O3- SiO2. The results of calculations of surface tension were determined for temp. 1873 K and compared with the results obtained by T. Tanaka et al. [19]. In both cases the increase of Al2O3 content resulted in a growth of surface tension. The simulation results were higher than experimental result, as compared to the literature data.