Home – Home – Jornals – Avtometriya 2026 number 5

The systems of three features for the classification of natural and anthropogenic objects in the observation field using spectral channels of various widths from 5 to 90 nm have been studied. In comparison with previously obtained results, the effectiveness of using feature systems formed in the most informative intervals of the visible and near-IR ranges has been experimentally demonstrated. Systems of three features based on the formation of multispectral images in wide intervals of the visible and narrow intervals of the near-IR ranges have been identified, which ensure high accuracy in classifying objects in real scenes.

The review summarizes the results of research into the nature of temporal changes in the spectral reflectance of vegetation. The spectrum of vegetation’s reflective characteristics is considered to be a linear superposition of periodic (vegetation) components, a trend component, and an irregular component. It has been shown that variations in the spectral reflectance of healthy green plants at different phases of the vegetation cycle significantly exceed inter species variations. It has also been shown that the only universally accepted spectral signature of green vegetation is the red edge of photosynthesis - the Red Edge. Analysis of the spectral reflectance of plants in the range λ = 0.4-2.5 μm and its changes over time shows that, with the correct selection of the parameters of the hyperspectral imaging system (spectral resolution of about 2.5 nm and spatial resolution from 5 mm), as well as the timing and frequency of imaging, it is possible to solve a number of practical tasks related to determining the type of plants and their condition.

An algorithm has been developed that solves the problem of searching for an object moving in the plane of a video frame along a curve of a given shape among many similar objects in a video sequence. It is based on iterating through possible trajectories defined by the positions of the objects in two selected frames. For each trajectory, the initial speed of the target and its acceleration are estimated. The trajectory is selected such that, while moving along it, the target passes closest to the positions of the objects recorded in all frames. The algorithm has been tested on model data. Dependencies of its efficiency on the length of the video sequence, the average number of objects in the image, the shape of the trajectory, the nature of the movement, and the noise level have been obtained.

A statistical model of the gamma spectrum at the output of a spectrometer with a scintillation detector has been proposed for the spectrometry of a sample containing a large number of different radionuclides. The model is based on representing the observed number of pulses at the output channels of the gamma spectrometer with a scintillation detector during the exposure time as an ordinary stationary Poisson integer process. It takes into account that the energy spectrum of gamma quanta at the detector input is a superposition of the spectra of each radionuclide in the sample, as well as background radiation.The shape of the gamma spectrum of the background and each radionuclide is defined by a corresponding normalized vector, while its intensity is determined by the total area of the radionuclide's spectrogram. An analytical expression for the probability density of the total gamma spectrum has been derived. A synthesized algorithm for estimating the areas of the components of the total gamma spectrum, based on the proposed model, is presented. Using the example of analyzing a sample containing three radionuclides (⁶⁰Co, ¹⁵²Eu, and a background with ¹³⁷Cs backlighting), the high efficiency of the algorithm is demonstrated through computer simulation.

The paper presents the results of reflectometry data processing for ice surfaces using navigation satellite radio signals. A fast Fourier transform (FFT) procedure was used to process the obtained amplitude-time dependences. The results and processing methods allowed us to identify functional relationships between ice thickness and the altitude of the navigation receiver's phase center, the navigation satellite's elevation velocity above the horizon, and the characteristic frequencies identified through Fourier transform analysis.

It is noted that the current values of the instrumental error of circular measurement scales are determined only at a finite set of points along the scale. It is proposed to characterize the instrumental error of such scales as a discrete, periodic distortion function and to employ the delta-function formalism to analyze its impact on measurement results. It is shown that, in model experiments using this approach, two modes of operation for specialized sets of reading heads are observed, depending on the properties of the measurement scale. The first is the canonical variant, which exhibits all the properties expected of the EDA method-namely, harmonic filtering and a corresponding increase in measurement accuracy. In the second variant, harmonic filtering is absent, and the improvement in accuracy depends linearly on the number of heads used; this variant is termed non-canonical. It is proposed that this interpretation of instrumental error be applied to the analysis of multi-combination angular sensors.

The paper presents the results of the search for a unified solution to the problem of constructing an automatic control system for aircraft with various aerodynamic configurations. The structure of an aircraft motion control system based on a total energy control method in the longitudinal channel and a full heading control method in the lateral channel is presented. The results of motion simulations for several aircraft models with a control system are presented, demonstrating combined control of the longitudinal flight path and speed, coordinated turns, compensation for dynamic and static thrust asymmetry, and priority speed control when approaching thrust limits. The research results confirm the possibility of creating an effective aircraft control system based on the total energy method.

For dynamic diffraction experiments at the "Plasma" section of Station 1-3 ("Fast Processes") at the SKIF Shared Research Facility, the SciCODE semiconductor one-dimensional detector-which operates in direct X-ray photon counting mode - is being developed. Photons are absorbed in a semiconductor microstrip sensor, with each strip connected to an input contact of the SciCODE64C bare-die readout chip. The chip features 64 channels arranged with a 70 µm pitch. Each channel comprises a charge-sensitive amplifier, a shaping amplifier, four comparators with adjustable thresholds, four 8-bit counters, an output shift register, and a control register. This article describes the design of the readout chip and presents initial results from the measurement of its key characteristics.

The possibility of using a typical PID controller to organize an automatic extremum seeking in systems with a second-order dynamic plant and a nonlinear quality function that has a minimum or maximum is considered in this paper. To reduce potential control peaks, it is proposed to modify the controller by moving the proportional and derivative components to the feedback channel relative to the dynamic component of the plant. Additionally, a special low-pass filter is added to suppress the influence of measurement noise. Extremum seeking with incomplete information about the quality function is organized by using an estimate of the extremum characteristic gradient in the controller. A synchronous detection method is proposed for obtaining this estimate. The parameters of the PID controller are determined using the large coefficient method and the modal approach with the desired distribution of roots in the system. The controller calculated in this way ensures the achievement of an extremum in statics, as well as robustness in relation to changes in the dynamic part parameters of the plant. The presented results of numerical simulation of the system in MatLab illustrate its main properties.

A method that allows representing timing diagrams describing the operation of large physics facilities as a system of linear equations and graphs is presented in this article. Constraints for such diagrams are represented as a system of linear inequalities. The presented method allows convenient modification and verification of complex timing diagrams. The software that built on the basis of this method is discussed. It is currently used to define and edit a timing diagram of more than 2,000 events at a large accelerator complex.

The development of a decentralized control algorithm for a dense configuration of a group of mobile robots is considered. A modification of the heuristic algorithm is presented, which includes adaptive parameters for robot interaction, enhanced attraction to the target position in the near zone, and an angular displacement mechanism to reduce the effect of local minima. A software system for numerical simulation based on ROS and Gazebo has been developed to study the reconfiguration processes in a group of mobile robots. The effectiveness of the proposed algorithm is assessed through numerical simulation and comparative analysis with a classical control algorithm.

The paper substantiates a generalized method for calculating the phase transmission functions of modified lenses with increased depth of focus. An approach is proposed that uses not only the ray equation, but also a method for specifying a condition that determines the redistribution of energy from certain zones of the optical element to certain areas of the caustic. This allows you to specifically select the type of aberrations introduced. For three types of radiant energy flux power gradients, the types of aberrations introduced using aspherics were determined, and the phase transmission functions of the modified lenses were found. In the Kirchhoff-Fresnel scalar approximation, the intensity distribution in caustics is calculated. The intensity distributions along the optical axis of the focal segments of the modified lenses show significant fluctuations relative to the average values. The average values vary along the optical axis and have a magnitude of about 10^-2 of the intensity at the focus of an ideal lens. The sizes of axisymmetric scattering circles in different sections of the focal segment also vary significantly relative to the Airy circle of the lens.

This paper addresses the problem of multifactor efficiency analysis of complex technological processes under conditions of physical heterogeneity and high dimensionality of experimental data. The aim of the study is to develop an algorithm for the comparative analysis of operating conditions based on the Data Envelopment Analysis (DEA) method, providing interpretable efficiency assessments and identifying potential directions for process optimization. The catalytic methane pyrolysis process is considered as the object of investigation. An algorithm integrating preliminary statistical analysis with a set of DEA models (CCR, BCC, Super-Efficiency, and SBM) has been developed. The proposed approach enables efficiency evaluation, analysis of scale properties, and quantitative determination of input and output parameter reserves. A decision-making matrix integrating comparative efficiency scores, scale efficiency indicators, and parameter reserves into a unified analytical tool is proposed. The matrix allows ranking of operating conditions, identification of inefficient process regimes, and determination of priority directions for optimization and scaling. The proposed approach was validated using experimental data obtained from an operating methane pyrolysis unit, including 546 measurements collected under 25 technological operating conditions.

Vertical PIN mesa-photodetectors in the wavelength range 1310-1550 nm based on Ge/Si heterostructures have been fabricated and characterized.The undoped and doped Ge layers were grown by molecular beam epitaxy on Si(100) highly doped p-type substrates. The level of Sb doping in the n+ region and the Si diffusion profile in Ge were determined by secondary ion mass spectrometry. The threading dislocation density was reduced to 2·10⁷ cm^-2 due to the implementation of a two-stage growth process for Ge followed by thermal annealing. According to X-ray diffractometry data, the residual tensile deformation of the Ge epitaxial layer on a silicon substrate after annealing was +0.11%. At a reverse bias of 1-2 V, the photodetectors showed high sensitivity at a wavelength of 1310 nm (0.5 A/W with a thickness of 1.5 µm) with a moderate dark current density (1-2×10^-2 A/cm²). These results are promising for the efficient development of photonic integrated circuits on silicon.