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Документ Development of models of the electromagnetic environment in buildings and urbanized areas(Технологічний центр, 2022-12-30) Levchenko, Larysa; Ausheva, Nataliia; Burdeina, Nataliia; Aznaurian, Iryna; Biruk, Yana; Kasatkina, Nataliia; Matvieieva, Iryna; Nazarenko, Vasyl; Nikolaiev, Kyrylo; Tykhenko, OksanaA set of measures and means to control the electromagnetic situation of the environment in the territories of urban development, in buildings and individual premises has been substantiated and developed. The simulation tools show the ability to rationalize the parameters of overhead lines with voltages of 220 kV and below, which will reduce the electromagnetic load in the territories. Modeling the propagation of fields from underground high-voltage lines has established that the values of magnetic fields compared to overhead lines are lower up to 30 times. Models of propagation of electromagnetic fields of very high and ultrahigh frequency were built. Sources of electromagnetic fields of non-production origin in industrial buildings have been investigated. Uncompensated currents in power networks with nonlinear electric consumers generate magnetic fields by induction of 0.35–1.20 μT, which exceeds the maximum permissible levels of operation of computer equipment. Leakage currents on grounded metal structures generate magnetic fields with 1.52–6.75 μT. Simulation of the propagation of electric and magnetic fields of components of personal computers of controlled ranges according to the MPRII standard was carried out. Models of propagation of the magnetic field of industrial frequency around electric motors and generators with their cross sections were built. On the basis of such models, design schemes for placing equipment in production areas are selected or places of safe stay and movement of personnel are selected. The expediency of using shielding to reduce field levels to safe values due to coating surfaces with liquid protective mixtures was shown. Metal-containing composition based on water-dispersion paint makes it possible to reduce the level= of magnetic field of industrial frequency by 2.5–2.6 times, electric field by 1.6–1.7 times, electromagnetic field of industrial frequency – by 1.2–1.3 times.Документ Monitoring And Management Ion Concentrations In The Air Of Industrial And Public Premises(2022-02-25) Bolibrukh, Borys; Glyva, Valentyn; Natalia, Kasatkina; Levchenko, Larysa; Tykhenko, Oksana; Panova, Olena; Bogatov, Oleg; Petrunok, Tetiana; Aznaurian, Iryna; Zozulya, Sergey; Aznaurian, IrynaThis paper reports a substantiated method and a designed device for controlling the concentrations of air ions in premises in accordance with the European standards SBM 2015. The use of an ultrasonic humidifier with a capacity of 25 W for two hours increases the concentration of negative ions around the device from 240 to 560 cm-3, positive ones ‒ from 260 to 410 cm-3. The intensity of the electrostatic field of a polymeric coating decreases from 5.1 to 0.2 kV/m. The disadvantage of the humidifier is a small radius of influence (1.0–1.5 m) and the inability to control the polarity of ions. It has been experimentally established that air cooling systems (split systems) deionize the air of the premises. Degrees of deionization and dominating polarity are unpredictable and different for devices of different manufacturers and brands. To control the ion composition of the air simultaneously with the maintenance of normative relative humidity and stresses of static fields, the structure was proposed and the effectiveness of a bipolar ultrasonic air ionizer with adjusted performance and dominating polarity has been tested. The maximum productivity of the ionizer is 4,000–5,000 cm-3. The radius of exposure is 5 m (reducing the concentration of ions with a distance to 500 cm-3). To pass the ionized air through an air capacitor, the number and predominant polarity of air ions are regulated by the polarity and voltage on the covers of the capacitor. It was established that in order to service a room with an area of 50 m2, an ultrasonic emitter with a capacity of 25 W would suffice. The adjustability of the device performance makes it possible to reduce or increase the service area. The ability to purify air from suspended particles is shown. During the two hours of operation of the ionizer, the dust content decreased from 4.3–4.4 mg/m3 to 1.4–1.6 mg/m3.