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A problem of upgrading an optoelectronic scanning system with digital post-processing of the signal based on adequate methods of energy center localization is considered. An improved dynamic triangulation analysis technique is proposed by an example of industrial infrastructure damage detection. A modification of our previously published method aimed at searching for the energy center of an optoelectronic signal is described. Application of the artificial intelligence algorithm of compensation for the error of determining the angular coordinate in calculating the spatial coordinate through dynamic triangulation is demonstrated. Six energy center localization methods are developed and tested to select the best method. After implementation of these methods, digital compensation for the measurement error, and statistical data analysis, a non-parametric behavior of the data is identified. The Wilcoxon signed rank test is applied to improve the result further. For optical scanning systems, it is necessary to detect a light emitter mounted on the infrastructure being investigated to calculate its spatial coordinate by the energy center localization method.

A method of measuring the velocity of phase structures by means of emulation 2D spatial filtering of their images formed on the matrix of a digital camcoder is discussed. As an example, visualized fields of the phase optical density in convective flows induced in a high-viscosity fluid are considered. Investigations of this kind of flows are useful for simulating the Earth's mantle behavior at large depths.

This study describes the laser generation of a 6G rhodamine in artificial opals representing single-crystal and heterostructure films. The spectral and angular properties of radiation and the threshold characteristics of generation are investigated. In the case where the 6G rhodamine was in a bulk opal, the so-called random laser generation was observed. In contrast to this, the laser generation caused by a distributed feedback inside the structure of the photonic bandgap was observed in photonic-crystal opal films.

The properties of polarization holographic gratings formed in liquid crystal polymer composites doped with nonmesogenic nanoparticles (SiO₂, ZnO, Al₂O₃, and Y₂O₃) are considered. The effect of these additives on the phase transition temperature of liquid crystals of polarization gratings, diffraction efficiency, and driving voltage is demonstrated.

The development of additive technologies and their application in industry is associated with the possibility of predicting the final properties of crystallized added material. The paper describes the problem characterized by a dynamic and spatially nonuniform complexity, which, in the case of uniform decomposition of a computational domain, leads to unbalanced loading on computing cores. The strategy of partitioning of the computational domain is used, which minimizes the CPU time losses in the serial computations of the additive technological process. The chosen strategy is optimal from the standpoint of a priori unknown dynamic computational loading distribution. The scaling of the computational problem on the cluster of the Institute of Laser and Information Technologies (RAS) that uses the InfiniBand interconnect is determined. As a result of using the parallel code with optimal decomposition, it was possible to significantly reduce the computational time (down to several hours), which is important in the context of development of the software package for support of engineering activity in the field of additive technology.

This paper describes the production of analog-digital integral reading circuits for photosignals of hybrid multielement infrared photoreceivers (silicon multiplexers). This work contains the estimation of noise equivalent temperatures of infrared photoreceivers based on multiplexers with frame-by-frame and row-by-row acquisition of signals of photosensitive elements of the spectral ranges 8 to 14 and 3 to 5 m. This paper also presents the development of silicon multiplexers for infrared photoreceivers designed with the use of photodiodes based on the cadmium-mercury-tellurium compound and photodetectors on multilayer structures with quantum wells. The designed multiplexers ensure the use of matrix and ruled photoreceiving crystals, include those with increased dark currents, in order to produce infrared photoreceivers whose temperature resolution corresponds to worldwide standards.

It is experimentally found that shut-in pressure conforms with the fracture initiation pressure if fracture surfaces are uniformly loaded by fluid. The article shows that equaling minimal stress and shut-in pressure in local fractures results in overestimates. The error depends on the length of a hydrofracturing facility and is high under low compression in rocks (5-10 MPa). The authors put forward decisions aimed at improvement of accuracy and enhancement of information content of hydraulic fracturing in the in situ stress measurement.

The authors discuss capabilities of taking information on mechanical processes in geomaterials under post-limiting elastic deformation based on variation in IR radiation intensity. Experimental results on recording of heat emission from specimens of rock salt exposed to cyclic loading by uniaxial compression are reported. It is concluded that thermomechanical effects are useful in recording of onset of failure activation in geomaterials under cyclic loading.

The article describes physical simulation and mathematical modeling of influence exerted by injection of thermogel on configuration of water flow in water flood recovery. Recovery of oil, especially viscous oil, with such method features unstable displacement front and formation of water fingers that eventually turn into a net of water channels directed toward the lowest flow coefficient between wells. Most of oil remains immobile and is in dynamic equilibrium with the displacement water flow. The authors show that injection of thermogel in a reservoir between wells expands displacement front at the late stage of mining, which allows enhancement of oil recovery factor.

The authors describe operation of a laser deformograph within the integrated geodynamic monitoring system in Streltsov Ore Field. Capabilities and design features of the deformograph are discussed. The article demonstrates feasibility of highly accurate measurements of deformation field parameters in an operating mine. Specificity of natural oscillations of the Earth is defined, and deformation of rock mass depending on energy of a destruction source is evaluated.