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The paper presents an analysis and forecast of the development of hybrid electric and full-electric propulsion systems for an aircraft of different types, key technologies necessary to develop them.

The methods of increasing the radiation power of metal vapor lasers has been considered. The results of the using different types of discharge circuits are presented. The use of matching line with the peaking capacitor and the autotransformer provides additional time delay between current and voltage of the gas discharge tube. It allowed increasing in the radiation power by a factor of 1.5 and the laser pumping efficiency to ~ 1.6%. Dependences of the radiation power in the direct discharge scheme and in the scheme with matching line are represented.

High initial currents are required for effective operation of multi-element disk magneto-cumulative generators (DMCG). The DMCG powering is provided by an energy preamplifier (helical MCG). Having a lot of contact connections located on a small radius, it is necessary to power the DMCG during a short time period; that is the preamplifier should be of high-speed. In the report, there are the results of the first experiment with a high-speed helical MCG with an internal diameter of the turns of 320 mm. The generator provided the current of 8.5 MA (magnetic energy of 10.6 MJ) with a characteristic rise time of 38 µs in the load of 300 nH at the energy powering of 120 kJ; this is equal to the initial inductance of the 15-element DMCG with a HE-charges of 480 mm diameter.

The aim of the development is a cardiograph unit that will produce daily monitoring of the patient, the processing of the data and their transmission over the wireless channel. The module detects characteristic points using digital filter unit, which can determine the state of the cardiovascular system.

Methods for changing CuBr vapor laser operating parameters by varying discharge circuit parameters of a power supply were observed. Various options of matching the power supply and the active element were tested to obtain a steady amplifying state with an atypical duration of pulse radiation. Use of the matching autotransformer made it possible to increase the power of generation two-fold and to stabilize discharge parameters at the increased input power in a medium. The pulse duration of the superradiation of 80ns was obtained in the stationary pulse-periodic operating mode. The active element can be used for monitoring the objects located at the distance more than 10m from the brightness amplifier. The comparative characteristics of the obtained images depending on the ASE pulse duration were carried out.

The main problem in diffuse optical tomography is too low spatial resolution due to the multiple scattering of light. For solving this problem we have recently proposed a perturbation model that uses the early arriving diffuse photons for reconstructing the local disturbances of absorbing and diffusion coefficients. In the paper we develop our approach and derive an analytical representation of the sensitivity functions, which model the imaging operator, for parallel-plate transmission geometry. We first derive analytical expressions for the case of a semi-infinite scattering medium by using Green's function of the non-stationary diffusion equation and then apply these expressions to evaluate the sensitivity functions for parallel-plate transmission geometry using an original method of equivalent inverse source. The efficiency of our approach is demonstrated through a numerical experiment wherein the absorbing and scattering inhomogeneities in a rectangular scattering phantom are recovered using an original hybrid algorithm which combines the algebraic reconstruction technique with regularization via total variation norm minimization. It is shown that the transverse resolution as well as the longitudinal one can be better than 4 mm inside a 8-cm-thick phantom.

The results of the development of configurable educational stand on analog and digital circuitry laboratory works are presented in this paper. The stand's flexibility allows changing the set of the objects under study (to change the configuration) and lets you adjust the stand and laboratory works to electrical engineering, industrial electronics and other disciplines. Students, which are working with a stand, are not dealing with a component's graphic symbols but with the real radio-electronic components. The basic stand's version covers 8 laboratory works in analog and digital circuitry. Designed-in resources allow to expand the list of studied topics up to 100.

Actual methods of the long lasing pulse obtaining in CuBr active medium was observed. A compact pump source, which can be used in mode with low energy input in the discherge was developed. The source is stable working in low frequencies (2–3 kHz) and allows to achieve a pulse duration up to 100 ns. Moreover, this source allows to operate with the pulse repetition frequency of up to 50 kHz. Developed device was used to study the influence of the distance between the observed object and the brightness amplifier on the image quality and on the process of signal amplification in active medium. In case of working in the mode with atypical duration of laser pulse it is became possible to image the objects at a distance up to 9 meters with no loss in images quality.

The paper presents SEE test results of COTS components considering to be applying in satellite equipment and critical to SEL and/or catastrophic failure. They were provided to confirm electronic components required hardness level and to define of the survivability in latched condition if SEL were observed during the experiment. In several cases LET thresholds were determined as it was specified in the requirements.

Explosive and electro-exploded opening switches are used for current sharpening of magneto-cumulative generators (MCG). The electro-exploded opening switches (EEOS) are well studied both in calculations and experimentally; the explosive opening switches (EOS) have been studied mostly experimentally. Calculation and theoretical studies of the explosive current opening switches has been carried out by means of phenomenological model building or in two-dimensional gas-dynamic approximation. The mentioned approaches have some limits, and they do not allow completely revealing the complicated pattern of physical phenomena taking place during the opening switch operation. Whereas it is necessary to optimize the explosive opening switches, it is almost impossible to solve this problem completely at expensive full-scale explosive experiments. Two-dimensional numerical magneto-hydrodynamic simulation of the processes is very close to the reality. The paper describes the statement of problem, compares calculation and experimental data on the circuit breaking of the magneto-cumulative generator using the explosive current opening switch with the ribbed barrier. Investigation results of the electric circuit parameters, opening switch construction, and linear density of the breaking current dependence on the load current pulse characteristics are presented. Possible reasons of differences in calculation and experimental results are shown; ways of improvement of the calculation model and opening switch optimization are outlined.

Nowadays disk magneto-cumulative generators (DMCG) are the most powerful and power-consuming magneto-cumulative generators (MCG). The problem of necessary initial energy supply to the generator circuit is very urgent at creating high-performance disk generators. Preliminary energy amplification in experiments with DMCG is provided with helical MCGs. Along with preset energy supply, the preamplifier should have small characteristic current rise time. It is necessary for decreasing thermal and mechanical supply current effect on elements of the disk generator. This means increasing the output power of the preamplifier and associated with obtaining maximum possible initial energy in the DMCG. Initial inductance and resistance of the DMCG circuit became higher with increase of the DMCG sizes and the number of its elements. This required increasing the power of earlier used preamplifiers. The paper presents experimental results of the MCG-240 characteristics improvement at the expense of turns distribution change and application of more powerful explosive. Other possibilities of the preamplifier power increase are considered in the paper.

A cyclic tension and alternating bending tests of 12Cr1MoV steel specimens in as-supplied state and after surface nanostructuring by Zr+ ion beam have been carried out. Distinctions in formation of strain induced relief, as well as the cracking pattern of modified surface layer are illustrated by methods of optical microscopy and interferential profilometry. Changes to occur in subsurface layer are characterized by means of nanoindentation and fractography observation of fracture surfaces. The description of differences of deformation behavior is performed with use of the multiple cracking concept.

The paper considers a new iterative algorithm for tomographic image reconstruction when a very limited number of projections are registered. The algorithm uses a priori information on the discrete values of the object function to be reconstructed and is based on the known multiplicative algebraic reconstruction technique (MART). The new algorithm we called MART-AP organizes a cycle of “external” iterations where the image is corrected at each iteration, using the MART and an image mask synthesized with the help of a priori information. It has been shown in numerical experiment that the algorithm proposed helps completely remove streaklike artifacts usually present on the tomograms which were reconstructed in conditions of strongly incomplete data.

The results of researches of influence of reflecting characteristics in the waveguide ferrite polarizer of 3-cm range of electromagnetic oscillations on polarization of waves are presented in the report. The polarizer is the section of the circular waveguide with the rectangular ferrite plate in the external magnetic field of the solenoid. The reflectivity coefficient and polarization characteristics were investigated at the change of magnetic field strength and an angle of the first installation of ferrite.

The photon average trajectory method reduces the inverse problem of diffuse optical tomography to solution of an integral equation with integration along a curvilinear photon average trajectory. As a result, the discrete reconstruction model with the one-step inversion of a system of linear algebraic equations can be applied. For solving the system, we use the multiplicative algebraic reconstruction technique modified to improve the quality of diffusion tomograms. Space-varying restoration and methods of nonlinear color interpretation are applied for postprocessing. To study the efficiency of proposed methods, a numerical experiment is conducted, where a rectangular scattering object with circular absorbing inhomogeneities is reconstructed over optical projections simulated for the time-domain measurement technique. It is shown that our approach allows reconstructing images with quality close to that of well-designed multi-step algorithms at considerable savings of computational time.

Summary form only given. The paper presents investigation results on development of soft X-ray radiation sources based on imploding multi-wire Z-pinches, powered from magneto-cumulative generators. Parameters of the source, realized with fast helical magneto-cumulative generator MCG-200, are close to calculation results: an energy of the X-ray radiation is 180 kJ in a pulse with the width at half height of ~20 ns, the pinch plasma temperature is 65 eV, a current amplitude in the liner load is 5.3 MA at a rise time of 400 ns. The research on optimization of the X-ray radiation source parameters with the power source based on the magneto-cumulative generator of 240 mm diameter are being continued. Up to now the current of 14 MA amplitude and rise time of 1.3 mus could be supplied into the liner load . A length of the generated pulse of the X-ray radiation is 60 ns at half height, the pinch plasma temperature is ~60 eV.

A device was developed for experimental research, in which the field of laser radiation with intensity, structured in space, is formed. It allows more a rational distribution of energy of laser radiation in space and strengthens the effect of light on atoms. The basic optical circuit of the experimental stand is submitted; the technique relies on a tabletop continuous argon laser, LGN-506, generating radiation of 4 W, at two wavelengths. The radiation in a strip of absorption was used on atoms, and a second beam was used for the control of isotope concentration distribution. The gradient of isotope concentration is continuously supervised with the help of an interference circuit. For the control of kinetics a concentration gradient is formed using a computer with an interface to photoreceivers. A quantitative determination of the isotope separation factor is carried out using the MCX-4 spectrometer. The technique of isotope separation is fulfilled with the help of Xe, which has stable isotopes 124, 126, 130, 131, 134, and 136. The strip of absorption of xenon coincides with the spectral range of argon laser generation which is 0.46-0.51 microns.

During the study of processes that take place in low-temperature plasma it is necessary to determine different parameters of the plasma system. One of the relevant parameters is the energy of system. The energy of the system can be spent by various methods. One of them is the energy radiance. This paper dedicated to modeling of parameters of a low-temperature plasma with various additions of alkaline metals.