Home – Home – Jornals – Avtometriya 2020 number 1

The principles of design of projectors of infrared (IR) scenes on the basis of micromirror technologies, which are the most promising devices for IR image generation, are analyzed. Several types of projectors based on these principles are considered from the viewpoint of functionality, noise minimization, and wavelength range in which these images are generated. Problems arising in design of IR scene projectors based on DMD technologies for generation of long-wave IR images are discussed.

Specific features of spectral properties of three-dimensional reflection holograms are determined, namely, widening of the spectral response (reflex) contour toward both the short-wave and long-wave spectral ranges in the case where the angle of incidence of the white-light probing beam differs from the direction of reference wave propagation in hologram recording. This effect is essentially different from the known angular dependence of the reflex of the elementary three-dimensional reflection grating. A theoretical explanation for experimental data is provided, and formulas are derived, which are used to calculate the transmission spectra of the studied gratings. These spectra are found to be qualitatively consistent with the experiment.

An approach to filtration of hyperspectral images distorted by the Gaussian additive noise is proposed. The approach is based on using the property of interchannel redundancy of such images. The developed algorithm of noise filtration allows maintaining the planimetric and brightness portraits of objects in individual components of the hyperspectral image, in contrast to algorithms of linear component-by-component and vector filtration, as well as the algorithm of averaging over a set of components. The numerical results obtained in the study testify to the advantage provided by interchannel gradient reconstruction in terms of the accuracy of recovery of hyperspectral image components distorted by additive noise. The efficiency of the proposed approach is demonstrated by an example of processing of real hyperspectral images.

The implementation of algorithms for comparative analysis of television image quality is considered. It is proposed to use the Xilinx Zynq-7000 platform, combining the advantages of FPGA and a general-purpose processor, to provide continuous on-line operation. A software architecture of algorithms for comparison of the video signal quality by a measurement with a full standard measurement method is proposed.

The influence of a viewing device - a multifocal 3D display - on the visual perception and user assessment of the depth and size of objects is analyzed. IN As an experiment model we used the Holway-Boring technique, which has proved that the constancy of size perception plays a decisive role in distance perception. The series of experiments performed shows that multifocal 3D displays provide fairly reliable information about the remoteness and size of objects, making it possible not to violate the law of constancy of perception

A swarm of moving objects coordinates the position of its individual objects in order to simultaneously solve a general task set in a distributed manner. Planning the swarm operations comes across a problem of taking into account the possibility of operational regrouping of the swarm as the exact purpose of the swarm operation is not yet determined, or is a secret, or is set by a number of random circumstances. At the same time, the swam resources are not sufficient to simultaneously cover all possible targets in the operating range. Therefore, it is advisable to carry out the swarm operation in two phases and begin the first preliminary phase before resolving the mentioned uncertainties by creating a basic network with a relatively low concentration of swarm objects therein. In this case, one can significantly reduce the operation time. In the second phase of the operation, one locally simultaneously regroups the swarm objects, which takes a minimum time, to form a programmable percolation path that provides targeted coverage of the operating range. The solution to this problem is carried out by methods of the programmable percolation theory. The value of the swarm object concentration is obtained numerically using the results of statistical modeling of two-phase operations and analytically, thereby providing a minimum of total costs of the two-phase operation. The synergetics of information interaction of the swarm of objects in the implementation of a programmable percolation path is considered

A new method is proposed for automatic classification of seismoacoustic emission sources in fiber-optic monitoring systems based on the principles of optical reflectometry in a time domain using the time reconstruction of the interference signal phase. The novelty of this approach lies in the original principles of forming a space of classification features and the use of ensemble classifiers. This method works provided that a relatively small training database is used. High practical effectiveness of the proposed approach is shown when working on real data. A classification reliability value previously inaccessible to alternative classification methods implemented in serial fiber-optic monitoring systems is evenly achieved for different classes of goals

Jet combustion of premixed propane-air mixtures is frequently encountered in various devices. In the present study, the flame is investigated by methods of the Hilbert optics. The diagnostic technique adapted to studying combustion products is based on visualization of phase disturbances induced in the probing light field by the examined medium with the use of polychromatic Hilbert and Foucault-Hilbert transformations combined with pixel-by-pixel processing of the dynamic structure of the recorded images. The diagnostic setup is based on the standard IAB-463M device with modified systems of optical filtration, source, and data processing. The dynamic phase structure of the propane-air flame is visualized. The temperature at reference points of the burning jet is measured by thermocouples. On axisymmetric segments, the phase function is recovered from the Hilbert curves, and the temperature field of the flame is retrieved by using the inverse Abel transformation.

This paper deals with the fuzzy modeling of technological processes and plants for which it is impossible or difficult to develop adequate mathematical models using multidimensional interval-logic controllers. Algorithms and software are proposed. The results of high-accuracy calculations using fuzzy modeling methods are presented.

The possibility of the operation of neural networks on minifloats has been studied. Calculations using a float16 battery for intermediate computing were performed. Performance was tested on GoogleNet, ResNet-50, and MobileNet-v2 convolutional neural and a DeepSpeech-v01 recurrent network. Experiments have shown that the performance of the specified neural networks with 11-bit minifloats is not inferior to the performance of networks with the float 32 standard type without additional training. The results indicate that minifloats can be used to design efficient calculators for operation of neural networks

This paper presents a new integrated circuit designed for reading signals in a silicon microstrip detector in experimental observations of fast processes on a synchrotron radiation beam. The first variants of this circuit were used in a prototype detector based on a microstrip silicon sensor and were tested on an intense synchrotron radiation beam at the VEPP-4M collider at the Institute of Nuclear Physics Siberian Branch, Russian Academy of Sciences. The results of the first measurements showed that the main objectives of this development were achieved: the temporal resolution and frame rate satisfy the initial specifications and the maximum recorded signal in a linear mode provides a significant increase in the recorded photon flux compared to the previous version of the detector based on gas technology. The main problem detected during testing of the prototype is the relatively high noise level, which will be reduced in the next version of the integrated circuit by optimizing some circuit solutions

Within the framework of geometric optics, this study analyzes the rotational tuning of the period of an interference pattern formed by converging light beams on a photodetector that is stationary relative to a mirrorless two-beam interferometer based on a beam splitting cube. Equations are derived, whose solutions are the dependences of the tuning range on the base position of the initial light beam on the input surface of the cube and on the diameter of this beam. These dependences are obtained for several refractive indices of the cube material, and the significance of this parameter for the characteristics of the interferometer under study is shown

An approach based on the application of high-performance capacitive microstructures as anti-aliasing filters in broadband pulsed terahertz spectroscopy in the case of low-frequency (sub-terahertz) measurements is considered for the first time. The approach was tested when measuring the spectra of reference samples - bandpass filters with central frequencies of 156 and 376 GHz and a bandwidth of 12 %. It is shown that the spectrometer measurement time is decreased by a factor of up to 12 with an improvement in the measurement accuracy by leveling the long-term drift of the normalization signal. It is supposed that this approach can be used to increase the dynamic range and the spectrometer signal-to-noise ratio in the sub-terahertz range