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The article is devoted to neural network text classification algorithms. This paper presents the main components of the text classification system, as well as the same problems associated with the use of the architecture of convolutional neural networks. The algorithm for obtaining vector representations of the dictionary is described.

Synthetic biodegradable polymers are considered to be a highly suitable materials for the targeted drug delivery devices creating. Especially promising is the use of the electrospinning technique, which makes it possible to obtain materials with a high surface-to-volume ratio that provides active diffusion of the drug into the body tissues. In order to control the rate of polymer degradation and drug release from polymer scaffolds surface modification techniques are widely used. This study was focused on the investigation of ibuprofen-loaded poly (e-caprolactone) electrospun fibrous scaffolds and modification of theirs surface. Scaffolds with two ibuprofen concentrations were obtained: 5 wt./wt. % and 10 wt./wt.%. The modification was conducted by the pulsed electron beam irradiation. The sustained release of the model drug over a period of one day from both non-treated and treated samples was demonstrated. It was shown, that treatment leads to an increase in drug release rate and does not change surface morphology of scaffolds and fibers diameter distribution.

Abstract The first results of experiments demonstrating refraction contrast in magnified (x2.5) images obtained using the Bremsstrahlung gamma radiation of 18 MeV betatron with a narrow tantalum (Ta) target inside are presented. The Ta foil-target with a thickness of 13 urn and a length of 4 mm along the electron beam was mounted in a goniometer inside the chamber of the betatron to guide her along the electron beam. In this case, a linear microfocus source of Bremsstrahlung gamma radiation with vertical and horizontal dimensions of 1.5 and 0.013 mm, respectively, is realized for direct-forward emission of radiation. The obtained magnified images of rectangular steel plates with thicknesses in the region of 15-0.3 mm and lead foils with thickness of 25 urn demonstrated a high resolution of their edges due to the refraction contrast effect, which is realized due to the refraction of microfocus gamma radiation on the surfaces of the lateral faces of the samples.

Elements composition of niobium surface before and after plasma treatment by runaway electron preionized diffuse discharge was investigated in atmospheric pressure nitrogen flow by means of an Auger electron spectroscopy. Surface characterizations obtained from Auger spectra show that plasma treatment by diffuse discharge after exposure of 120000 pulses provides ultrafine surface cleaning from carbon contamination. Moreover, the surface free energy of the treated specimens increased up to 3 times, that improve its adhesion property.

Abstract The analysis of mathematical modeling results on premise heating by a gas infrared emitter (GIE) during supply and exhaust ventilation operation is presented in this article. The model is presented in a one-dimensional non-stationary setting for an incompressible medium with allowances for the radiant heat flux transfer between opaque solid surfaces in the air. The air is transparent to thermal radiation. The traditional k-ε model is used for turbulence modeling. The possibility for creating comfortable conditions in the area of a horizontal surface with different heights, imitating laboratory equipment, is analyzed.

In this work chaotic dynamics contact interaction of two flexible Tymoshenko beams, under the action of a transversal alternating load is investigated. The contact interaction of the beams is taken into account by the Kantor model. The geometric nonlinearity is taken into account by the model of T. von Karman. The system of partial differential equations of the twelfth order reduces to the system of ordinary differential equations by the method of finite differences of the second order. The resulting system by methods of Runge-Kutta type of the second, fourth and eighth orders was solved. Our theoretical/numerical analysis is supported by methods of nonlinear dynamics and the qualitative theory of differential equations. Chaotic vibrations of two flexible beams of Timoshenko were investigated and the optimal step values over the spatial coordinate and the time steps for the numerical experiment were found. Convergence for all applicable numerical methods have been achieved and shown that chaotic signals are true.

Abstract We report high-pressure synchrotron X-ray powder diffraction data for the W-rich cubic ZrW2-xMoxO8 (x=0.4) up to 10 GPa with open decompression. This study shows that cubic- ZrW1.6Mo0.4O8 transforms to orthorhombic phase at the 5.04 GPa. Pressure-induced reversable amorphization of material was observed at 8.13 GPa. The obtained data suggest that W-rich cubic ZrW2-xMoxO8 (x=0.4) solid solutions are more attractive for creating products working under extreme conditions and mechanic stress.

The positive effect of assisting influence of high-density gas plasma formed by an independent plasma generator PINK on mechanical and tribological characteristics of Ti-C- Mo-S magnetron coating on titanium alloys at lowered to 350°C temperature of coating regardless of alloy structural condition was revealed by methods of calotest, nanorecognition, scratch testing and frictional material tests. The coating formed by means of a combined magnetron plasma method reduces titanium alloys friction coefficient in multiple times and increases wear resistance by two orders of magnitude. At the same time the mechanical properties of ultra-fine-grained titanium alloys obtained by nanostructuring do not deteriorate.

Abstract Simson’s method employed in cardiological diagnostics detects the presence or absence of late ventricular potentials to indicate cardiac pathologies. It has been a long time since the development of Simson’s method, but it is still used in clinics and is often mentioned in studies related to high-resolution ECGs and averaging of ECG signals. An optimal algorithm of high-resolution ECG averaging was chosen and implemented in this study. Efficiency of Simson’s method was assessed on the cardiac signal recorded using a modern hardware and software complex. The result of the study showed no relationship between late ventricular potentials and localized micropotentials on the ST interval in individual cardiac pulses.