Home – Home – Jornals – Avtometriya 2026 number 3

It is proposed to use spectral channels with a width of 30 nm as feature systems for classifying natural and anthropogenic objects in the field of observation. The effectiveness of using algorithms that select and process a small number of narrow-band multispectral images of real scenes formed in the most informative intervals of the visible and near-infrared ranges has been experimentally demonstrated. A system of three features is defined that ensures high accuracy in classifying objects in real scenes. The possibility of switching from systems of three features to systems of two features in the classification of combined classes of test regions of interest is shown.

A method for structural analysis of remote sensing data is proposed, based on a two-level decision-making system. At the first level of the system's structure, remote sensing data is decomposed using the signs of the components that make up the estimated correlation coefficient between spectral features. Based on this, four classes of spectral data are identified. At the second level of the system structure, each identified first-level class undergoes further decomposition according to the Euclidean distance values for the components of the correlation coefficient estimate between spectral features. The developed system was used in the structural analysis of remote sensing data of a dark coniferous forest damaged by the Siberian silkmoth. The obtained results were compared with those obtained using the NDVI and NDII spectral indices of remote sensing. Nonparametric probability density estimates were used to analyze the spectral indices of remote sensing data and the developed decomposition system methodology. A procedure for optimizing kernel probability density estimation is considered. Schematic diagrams of the obtained results are provided.

This paper explores the integration of computationally efficient neural networks into a multi-object tracking algorithm in video sequences to reliably predict subsequent trajectories. Several well-known neural network models are tested, and a new one is proposed. The models examined demonstrate improved trajectory prediction performance compared to the baseline ByteTrack algorithm, without significantly impacting performance.

The article examines variations in the psychophysiological state of migrants who have moved from regions with a southern climate to permanent residence in the Far North, using international students studying in Russia's northern region as an example. This type of move is accompanied by a stress response, which arises from a negative perception of the new environment. Therefore, monitoring changes in the psychophysiological state of migrants is necessary. For this purpose, it is proposed to assess subjects' motor control abilities using a stop-signal paradigm, electroencephalogram monitoring, and machine learning methods for processing the collected data. A comprehensive method for analyzing the obtained information is proposed to determine anxiety using biophysical markers.

The proposed data processing technique is designed to detect formation fluid influx during managed pressure drilling. The approach is based on multi-stage enrichment of time series with context-dependent features, which enables anomaly detection based on the dynamics of process parameters within the context of the ongoing technological operation. The method remains robust to variations in drilling operations and conditions. Experimental results demonstrate a statistically significant 13% relative increase in balanced accuracy achieved with the developed features.

This work is devoted to the search for conditions of stable unidirectional planar GaAs nanowires growth on Si(111) substrates using Monte Carlo simulation. The effect of temperature on the stability of the planar growth on a structured surface in form of trenchesis investigated. The influence of the nanowire growth front geometry on the probability of stable planar growth in trenches oriented along the [211 ] and [011 ]directions is demonstrated. The growth kinetics of planar and non-planar GaAs nanowires at different temperatures is analyzed. An increase in the probability of planar nanowirestable growth with increasing temperature is revealed. It is shown that the reason for the transition from planar to non-planar growth for any trench orientation is wetting of the upper part of the planar nanowire with a gallium droplet.

We investigate a method for forming birefringent microstructures in fused silica using a burst of ultrashort linearly polarized laser pulses separated by sub-nanosecond equidistant intervals. The method utilizes a tensile deformation wave induced by a pressure jump in the region of electron-hole plasma formation. This tensile deformation reduces the laser pulse energy required to reach the modification threshold of glass and to inscribe a birefringent structure. It is established that a sub-nanosecond burst of ultrashort laser pulses, comprising a first pulse with an energy no more than twice the glass modification threshold energy and followed by several subsequent pulses with energies an order of magnitude lower than the first, enables the creation of a submicron-sized birefringent structure. It is suggested that the mechanism of birefringence formation is based on the anisotropy of the deformation wave excited by the first pulse. This new approach to generating a sub-nanosecond burst is promising for increasing the writing speed of birefringent structures in fused silica, which can be used for fabricating various elements in photonics.

The paper considers the possibility of creating an automated device for detecting methane (CH₄) in the atmosphere based on tunable diode infrared absorption spectroscopy using stepwise frequency modulation of laser radiation. A feedback diode laser (DFB) operating at a wavelength of 1653 nm was used as the radiation source. The optimal value of the modulation amplitude has been determined. The possibility of detecting methane in concentrations from 6 ppm for an optical path of 60 cm is demonstrated.

A phase triangulation method, invariant to receiving-transmitting function nonlinearity nature, is proposed for objects geometric parameters precision control in the optical light source and receiver limited dynamic range conditions. The method is based on the algorithm of the closed area shape minimization, formed by the values for given phase shifts of recorded intensity and generated by the source brightness. It was shown in the work that the proposed method provides a similar error level when the receiving-transmitting function is linear and high metrological characteristics when it has nonlinearities and frequency response of the measurement complex source and receiving optical systems is not ideal.

The results of the development of a high-aperture telecentric F-Theta lens for a laser workstation using a femtosecond laser as a radiation source and designed for the production of optical grids and scales on elements of optical and mechanical industry products are presented. The features of lens alignment are discussed. The results of experimental studies confirming the possibility of recording optical scales with a minimum line width of 0.003 (for field is 6x6 mm) to 0.002 mm (for field is 3x3 mm) are presented.

This work demonstrates for the first time sum-frequency generation (SFG) based on a continuous-wave Yb-doped self-sweeping fiber laser. The use of a self-sweeping laser in the SFG process enables the development of frequency-tunable radiation sources. Synchronization of the self-sweeping laser radiation with that of a microchip laser is demonstrated. SFG near 532 nm with a tuning range of up to 50 pm is achieved. The peak power obtained is 11 mW, corresponding to a quantum conversion efficiency of approximately 2 % for the self-sweeping laser radiation. The demonstrated approach can be adapted for difference-frequency generation (including terahertz radiation) and is promising for spectroscopic applications.

Spectral and diffraction characteristics of color monochrome single-layer (R, G and B) reflection holograms, as well as a three-layer RGB structure in the form of their superposition on each other (stacks), intended for use as gratings of input/output radiation of color LED devices in AR displays, were obtained and analyzed. An experimentally established mismatch between the spectral characteristic contour widths of the obtained holograms and the KY-016 LED diode used in the experiments. Because of this reason fractions of useful intensities of the R, G, and B components of this device are only 64 %, 32 %, and 34 %, respectively, of their potential values. Based on the well-known CIE RGB color specification model, the actual intensity ratios were found for mixing the emissions of the color components of an LED diode in interaction with reflection holographic gratings in order to synthesize white color. When assessing the energy efficiency of input/output of radiation using reflection holograms and color LED devices, the main criterion is the maximum brightness of the total illumination for a given set of color components and white balance conditions, and not the maximum intensities of individual components of R, G, and B radiation.