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This article explores the application of the transformer architecture for encoding states in reinforcement learning algorithms. A new approach is presented, which integrates transformers with existing methods, such as Soft Actor-Critic (SAC), to enhance their performance and generalization ability. The results of experimental studies show that the proposed approach can improve learning in complex tasks of acquiring movement skills in a three-dimensional space.

The work is devoted to the experimental study of the effectiveness of methods of classification of green vegetation and camouflage materials according to their spectral characteristics. The studies are performed using real spectral data obtained on a multichannel spectrograph based on a dispersing element and a multi-element CCD ruler in the visible and near-infrared wavelength range. A technique is proposed for processing a set of spectral data in order to form a representative system of features and subsequent application of adaptive threshold algorithms for detecting objects. The effectiveness of using vegetation indices calculated for spectral channels with different widths and at different positions of the central wavelength as signs for classifying types of materials is investigated. Special attention is paid to the detection of differences between fresh and anthropogenic vegetation. It is experimentally shown that both two-channel and three-channel indices can be used as informative features in the classification of objects.

The purpose of this work is to improve the accuracy of measurements of the optical rotation angle (ORA) by analyzing the effect of the adjustment error of the differential phase polarimeter analyzer. The paper presents a scheme of a differential phase polarimeter used for the study of optically active substances. To analyze the effect of the alignment error of the rotating analyzer on the ORA measurements results, mathematical modeling of the process of forming an informative signal in the presence of a deviation from the perpendicular plane of the analyzer relative to the axis of radiation propagation is applied. The results of the study of the influence of the adjustment error on the accuracy of restoring the phase difference of two harmonic signals are presented. The results obtained make it possible to develop requirements for the adjustment of the elements of the differential phase polarimeter to increase the accuracy of the ORA measurements.

The dynamics of effective and physical (geometric) shrinkage of a holographic photopolymer material is studied by measuring the evolution of transmission spectra of volume reflection holograms during their recording. It is shown experimentally for the first time that physical shrinkage occurs to a significant extent already at an early stage of hologram formation, when its diffraction efficiency is insignificant (less than 0.05). It is established that the effective shrinkage values at the end of the exposure for small and large grating periods differ significantly, while the physical shrinkage is approximately the same. For the grating samples studied, the average refractive indices before and after exposure are estimated. A method and device for measuring the shrinkage dynamics of reflection photopolymer holograms have been developed, ensuring the minimal errors in estimating the shrinkage parameters. The research results may be useful for deepening the knowledge about the nature of hologram formation in photopolymer materials, as well as for practical use in the development of holographic elements and devices based on them.

The method of calibration of scales with an irregular structure typical for absolute angle encoders based on pseudo-random codes has been developed and tested. The calibration results at a level of ±2.2ʺ with an uncertainty of ±0.5ʺ, characteristic for the measuring and diagnostic unit AE.1686 used, are experimentally obtained. The reliability of the results of calibration of irregular scales is confirmed by the identity of the curves obtained when comparing them with the calibration curve of a regular scale formed at another radius in a single technological cycle together with one of the controlled irregular scales.

A fundamentally new model of an optical switch with decentralized control is proposed. The advantages of the proposed switch are the absence of optoelectronic conversion of the information signal and the possibility of constructing scalable circuits of low complexity. The switch circuit includes the following main elements: electrically controlled switch elements based on lithium niobate, Bragg filters, optical valves, focusing systems, a control lens system, and a local system for generating control signals. The calculation of the optical devices of the switch shows the possibility of its implementation and operation in the range of 1310-1460 nm for transmitting control signals and 1550 nm for the information signal to ensure interaction between data center devices.

The development of acousto-optical tunable filter with a synthesized spectral transmission characteristic is presented. The wide-aperture (wide-angle, tangent) geometry of acousto-optical tunable filters widely used in modern hyperspectral systems is considered. It is shown that they can be described with a single-coordinate model of acousto-optic interaction. The relationships between the driving radiofrequency signal characteristics, the parameters of the acoustic wave forming the grating, and the spectral transmission function of the acousto-optical filter are determined. The fundamental limitations on the spectral transmission function characteristics are revealed. In a linear transmission approximation, the deduced relations describe the operation of an acousto-optical filter with an arbitrary law of amplitude and frequency modulation of the driving signal. The results are applicable for development of acousto-optical spectral systems with a controlled transmission function.

The problem of determining the optimal initial composition of the reaction mixture is formulated in general terms. A method for solving this problem based on the simulated annealing algorithm is described. Computational experiments are conducted for the Michaelis-Menten enzymatic reaction and the aminomethylation of thiols. Parameters for the efficient operation of the algorithm are selected. Using the proposed method, the optimal initial composition of the reaction mixture ensuring the maximum yield of the target product is identified. An analysis of the effectiveness of this algorithm is presented by comparing it with the results obtained from other optimization methods.

An algorithm aimed at searching for small-sized (about ten pixels) objects with constant brightness on a non-uniform random background has been developed. The algorithm is based on the procedure for finding the conditional maximum of the product of probabilities for an object and a local background to have certain brightness values. For the background, these probabilities are estimated from a histogram constructed for an image segment. The algorithm is implemented for the case when all the brightness values of an object in the acceptable range are equally probable. The computational experiment is performed on twenty photographs of clouds with a size of 1200 ⨯ 1200 pixels. Ten circles with a radius of two pixels are placed on each photo. Of the two hundred objects set in this way, 169 are detected by the proposed algorithm, while the number of errors of the second kind is 280.

Three-dimensional time-of-flight cameras are increasingly used in robotics to provide information support for motion control tasks. They are also considered promising for solving docking problems with non-cooperating spacecraft. In this case, the magnitude of relative coordinate measurement errors that a time-of-flight camera can provide is very important. Random (noise) errors are analyzed in the present study, and the presence of significant correlations of random errors in measuring the range of time-of-flight cameras for neighboring pixels is revealed. For a particular example, an analytical solution is constructed that shows significant deterioration in the accuracy of distance measurements in the presence of this correlation.