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A software system is presented for implementation of a fire model on the basis of a recurrent neural network, which ensures real-time simulation of fire evolution. The quality of traditional learning and learning based on the Kalman filter in experiments performed with the neural network is compared. It is demonstrated that the fire overcomes obstacles in the form of regions consisting of incombustible materials owing to the global character of connections of the neural network simulating the fire.

A method of calculating the range of operation of thermal imaging systems during detection, classification, recognition, and identification of objects is considered. The method is based on finding the functional relationship of the sought quantities with the threshold temperature sensitivity and the temperature-frequency characteristic of thermal imaging systems in the cases of tracking objects in homogeneous and non-homogeneous fields of thermal radiation.

A groove coated with a layer of indium that fills the groove during its formation is generated on the lower surface of sapphire in a single process under the action of laser pulses. The process is performed by using a pulsed gas laser with a wavelength of 0.337 µm. The laser beam is focused through sapphire onto a surface coated with indium. The sapphire motion velocity is uniform, and the sapphire displacement during the time between two pulses is 10% of the light spot diameter. The groove is formed by using the scanning mode (multiple passes of laser radiation through the groove). The pulse energy density in a single pass is sufficiently large. The process is carried out in air. It is found that the optimal option is two passes when the specific resistance of indium in the groove is only 3.8 times greater than the resistance of pure (99.999%) indium bars.

A method for measuring the concentration of a biomarker (acetone in human’s breath), which is based on the use of glow-discharge emission spectroscopy in air is proposed for the purpose of noninvasive glucose monitoring in diabetes patients’ blood. The experimental setup and measurement techniques are described, and preliminary results of clinical trials of the developed system under ambulatory conditions are presented.

Circle diagrams for the complex amplitude reflection coefficient are used for the development of a multilayer mirror, which includes a thin metal film. The proposed method allows calculating the asymmetrical front mirror of a two-mirror multiple-beam reflected light interferometer, which generates an interference pattern in the form of symmetrical narrow light bands.

The structure of a GaInP/GaAs/Ge triple-junction solar cell (SC) with an integrated Bragg reflector (BR) is optimized, resulting in reduction of losses of transmitted (reflected) radiation in tunnel diode layers. The optimized structure of the SC with a BR is obtained by means of metalorganic chemical vapor deposition. 20 × 30-mm SC samples are manufactured. The samples of SCs with and without BRs are tested under the action of electron fluxes with the energies of 1 MeV. It is shown that the SC radiation resistance can be increased by integrating a Bragg reflector into the SC structure and decreasing the thickness of the middle p–n junction base.

Basic technologies used to develop shadowgraphs, interference devices, and schlieren systems of the first and second generations failed to solve some problems of modern gas-dynamic experiments, first of all, creation of comparatively inexpensive and compact systems for optical and physical measurements of gas-dynamic fields (visualization fields) with sizes of 800–1000 mm and more. The demand for unique optical systems for wind tunnels and ballistic ranges is expected to increase in the near future: it is only these tools that can ensure adequate experimental investigations of flows around airplane, helicopter, future flying vehicle, car, and missile models whose scales are close to real ones. (In wind tunnels, the gas flow impinges onto a motionless model, e.g., of a flying vehicle; aeroballistic ranges allow direct modeling of the motion of examined bodies.) New capabilities of optical methods of gas flow research are implemented: a posteriori investigation of wave fields deformed after passing through the gas flow, increasing the sensitivity of optical measurements by one or two orders of magnitude, and manyfold increase in the amount of information obtained in a complex gas-dynamic experiment. Advanced optical technologies are used to solve these problems.

Formation of ordered structures from a large number (~10⁴) of charged diamagnetic macroparticles in a cusp magnetic trap under microgravity conditions is experimentally studied. The experiments are performed onboard the International Space Station. Dusty plasma structures in a cryogenic d.c. glow discharge (cryogenic dusty plasma) are examined. Ultrahigh charging of dust macroparticles under the action of an electron beam is experimentally obtained and studied. Results of an experimental investigation of various regimes of the Brownian motion of interacting dust particles in the plasma are presented. A method of determining particle interaction forces in nonideal systems with isotropic pair potentials is proposed. The method is based on solving an inverse problem that describes the motion of interacting particles by a system of the Langevin equations and allows reconstruction of parameters of the external confining potential without using a priori information about the friction coefficients of particles.

A modern method of velocity measurement in a flow volume on the basis of few-projections optical tomography and correlation of moving particles is considered. The method is used to measure instantaneous three-dimensional velocity distributions in non-swirling and swirling turbulent jet flows. In addition to measurement of three-dimensional velocity distributions, specific features of this experiment are a larger depth of the measurement region (up to 40 mm) and a higher resolution of cameras (up to 4 MP as compared to previous authors’ tomographic measurements). To verify the correctness of tomographic measurements, the velocity in the plane passing along the jet axis is measured by the Stereo PIV method. The difference between the stereoscopic and tomographic measurements of three components of the mean velocity for the flows considered in this study is smaller than 10 %. A three-dimensional vortex structure of the core of a swirling jet is visualized with a spatial resolution of 3 mm.

The structure and evolution of thermogravitational buoyant jets in a high-viscosity fluid above a linear source of heat suddenly switched on are studied by methods of the Hilbert optics and interferometry. Such jets can be considered as a model of an upward flow in the spreading zone in geodynamic problems associated with the behavior of the Earth’s mantle at large depths. Based on the interferogram structure, three-dimensional reconstruction of the temperature field in the jet is performed. The Hilbert image of the reconstructed three-dimensional temperature field is compared with the Hilbert image and interferogram of the jet.