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In this paper the biofeedback therapy application is presented. The application is implemented in desired biofeedback system based on RaspberyPI. The EEG signal is taken using popular headset with forehead probe and ear reference one. A patient is trying to focus on desired task and should keep attention level above threshold, the threshold is given and monitor by therapist. The success factor during one therapy session should be more than about 80%, so therapist have to control the threshold. The application consists algorithm for automatic threshold correction based on interview with experienced therapist. [ABSTRACT FROM AUTHOR]

The Synchronous Reluctance Machine (SynRM) is an electrical machine in which the useful electromagnetic torque is produced due to rotor saliency. Its high power- and torque-to-mass ratio and very good efficiency make it a cheap and simple alternative for permanent magnet or induction motors, e.g. in electromobility applications. However, because of magnetic nonlinearities, the rotational speed and torque control of a SynRM is a nontrivial task. In the paper, a control algorithm based on a Hamiltonian mathematical model is presented. The model is formulated using measurement results, obtained by the drive controller. An algorithm is tested in the drive system consisting of a SynRM with the classical rotor and a fast prototyping card. The drive dynamic response in transient states is very good, but the proposed algorithm does not ensure the best efficiency after steady state angular velocity is achieved. [ABSTRACT FROM AUTHOR]

The basic aim of the task is to compile a temperature stratification system in an accumulation tank. The range of the thesis concerns the shape and dimensions of a stratification system for an accumulation tank. Thermal stratification is a process that comprises the maintaining of temperature stratification at different levels of an accumulation tank which reduce to a minimum the process of temperature equalization. It results from the fact that the thermal stratification in a tank significantly increases the installation efficiency and improves the process of energy storing. It is connected with a thermodynamic element quality, that is the higher the temperature, the higher the energy, and, thus, the thermosdynamic element quality. In this phenomenon, thanks to the same amount of accumulated thermal energy and average temperature, as in a fully mixed tank, the user has a higher temperature in the upper part of the tank at his disposal. It has significant importance in the case when there is a low-temperature heating medium that transfers heat to the accumulation tank. Such a situation occurs when heat is absorbed from synthetic freons used in cooling and air-conditioning systems. [ABSTRACT FROM AUTHOR]

• Fabrication of high energy band gap composite SiO x :TiO y layers of refractive index ca. 1.65. • Resulting composite SiO x :TiO y layers are amorphous and optically homogeneous. • Surface roughness of SiO x :TiO y layers is below 0.2 nm and autocorrelation length is ca. 7 nm. • Elaborated composite SiO x :TiO y waveguide layers have ultra-low optical losses (<0.25 dB/cm). • The influence of SiO x :TiO y waveguide layers surface parameters on optical losses have been determined. This work reports a study on low-loss waveguide layers for planar evanescent wave sensor applications. Crack-free SiO x :TiO y composite layers with refractive indices of ∼1.65, in the visible spectra range, were fabricated using a sol-gel method and a dip-coating technique. Layers of thickness in the 220–360 nm range were produced in a single coating process. By multiple coatings, SiO x :TiO y composite layers of thickness up to 1000 nm were produced. Fabricated layers demonstrated good waveguide properties in the Vis spectral range. The dispersion characteristics of the developed layers refractive index were determined using the spectroscopic ellipsometry method. Spectrophotometric tests validated their optical homogeneity. Using the Tauc method, the widths of optical band gaps were determined, and their high values (E g > 3.7 eV) attest to the amorphous nature of the layer material. The FT-IR studies testified to Si-O-Ti bonds, an attribute of amorphous SiO x :TiO y composites. The tests of surface morphology of the SiO x :TiO y layers, using atomic force microscopy, scanning electron microscopy, and optical profilometry, confirmed their high smoothness. Using the m -line method, waveguide properties and optical losses were examined. To facilitate the interpretation of the experimental results, the mode characteristics and the calculated impact of surface morphology of the waveguide layer. [ABSTRACT FROM AUTHOR]

Safety and reliability of constructions operated are predicted using the known mechanical properties of materials and geometry of cross-sections, and also the known internal forces. The extensometry technique (electro-resistant tensometers, wire gauges, sensor systems) is a common method applied under laboratory conditions to determine the deformation state of a material. The construction sector rarely uses ultrasonic extensometry with the acoustoelastic (AE) method which is based on the relation between the direction of ultrasonic waves and the direction of normal stresses. It is generally used to identify stress states of machine or vehicles parts, mainly made of steel, characterized by high homogeneity and a lack of inherent internal defects. The AE effect was detected in autoclaved aerated concrete (AAC), which is usually used in masonry units. The acoustoelastic effect was used in the tests described to identify the complex stress state in masonry walls (masonry units) made of AAC. At first, the relationships were determined for mean hydrostatic stresses P and mean compressive stresses σ3 with relation to velocities of the longitudinal ultrasonic wave cp. These stresses were used to determine stresses σ3. The discrete approach was used which consists in analyzing single masonry units. Changes in velocity of longitudinal waves were identified at a test stand to control the stress states of an element tested by the digital image correlation (DIC) technique. The analyses involved density and the impact of moisture content of AAC. Then, the method was verified on nine walls subjected to axial compression and the model was validated with the FEM micromodel. It was demonstrated that mean compressive stresses σ3 and hydrostatic stresses, which were determined for the masonry using the method considered, could be determined even up to ca. 75% of failure stresses at the acceptable error level of 15%. Stresses σ1 parallel to bed joints were calculated using the known mean hydrostatic stresses and mean compressive stresses σ3. [ABSTRACT FROM AUTHOR]