International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Paper deals with dynamic behavior of powerful electric drive for pump unit. The practical application of these electric drives is diverse. In industry they drive a wide range of mechanisms connected to them. Some of them are pumps with varying degrees of security for thermal or nuclear power plants. The nature of the flow of transient processes in the electrical machine often determines the behavior of the entire system, an element of which is the machine. As a result the values of the energy losses components in the induction motor have been obtained according to different values of initial resisting moment. Some of the study results have been presented graphically. An analysis has been made and conclusions from the results obtained have been done.

CoO, CuO or NiO supported on Al₂O₃ photocatalysts were prepared by impregnation and then calcination at 400^oC for 3 hours. The obtained samples were physico-chemically studied by Powder X-ray diffraction analysis, X-ray photoelectron spectroscopy and Scanning electron microscopy. The photocatalytic oxidative degradation of aqueous solution of Malachite Green (MG) dye as pollutant using CoO, CuO or NiO supported on Al₂O₃ under UV irradiation was tested. The results determined that the highest degree of degradation of MG dye after 120 minutes was achieved using NiO/ Al₂O₃ photocatalyst (82%) than that the other materials CuO/Al₂O₃ (64%), CoO/Al₂O₃ (59%) and Al₂O₃ (50%). The calculated apparent rate constants increasing in the order: Al₂O₃ (2.7×10^-3 min^-1)<CoO/Al₂O₃ (3.9×10^-3 min^-1)<CuO/Al₂O₃ (4.1×10^-3 min^-1)<NiO/Al₂O₃ (8.4×10^-3 min^-1).

Nickel ferrites having different stoichiometry supported on activated carbon (Ni_0.25Fe_2.75O₄-AC, Ni_0.5Fe_2.5O₄-AC, NiFe₂O₄-AC) were prepared by co-precipitation using nitrate precursors and activated carbon from peach stones and calcination procedure in nitrogen atmosphere. The physicochemical properties of these materials were studied by powder X-ray diffraction analysis (PXRD) and Mössbauer spectroscopy. The presence of spinel ferrite and additional hematite phases was established by PXRD. The photocatalytic properties of the so synthesized nickel ferrite-AC materials were tested and compared in oxidative degradation of Malachite Green (MG) and Reactive Black 5 (RB5) dyes under UV-light irradiation. The photocatalytic tests show that investigated samples lead to much higher degree of degradation of MG (86%-92%) compared with that of RB5 (17%-35%) due to their structure. The results proved that nickel ferrite-AC materials are more efficient photocatalysts for removal of MG as model contaminant from aqueous solution under UV light than RB5.

Controlling of objects with the feedback negative loop is widely used in industry, intelligent technologies, robotics and transport systems. A negative feedback loop by comparing of the prescribed value of the output value with measured value of it generates a control signal, which adjusts the output value of the object. Typically, the number of controlled output values is equal to the number of feedback channels acting on the object, but in some cases, the number of the channel can be more. This situation is especially frequent in transportation systems. In the problem of the design of regulators, they pay the most attention to ensuring the required static and dynamic control accuracy, but recently the attention to the conservation of the resource manager increased. This saves fuel or energy costs, which is especially important, for example, in space technology. The task of saving resources in the control of an object with an excess amount of control channels was not previously considered in the literature. In this paper, the problem is investigated by numerical optimization with simulation. In some cases, the cost of resource of the control by the different channels may vary. At the same time the cheaper resources can have the worst quality of the control, for example, it can has a discrete form or (and) less speed and so on. In this paper, we study such state of the problem and give its solution. It is shown that for a suitable choice of the cost function one can preserve rather high quality of the control, while ensuring saving of the controlling resources. Resource saving can reach in some cases 96%, which is illustrated by an example.