Home – Home – Jornals – Advanced Search

This paper presents the results of developing a pulse analyzer for a borehole geophysical instrument intended for spectrometric gamma-ray logging. The module is implemented using a field-programmable gate array and enables real-time signal processing. An algorithm for converting biexponential responses of a scintillation detector into trapezoidal pulses is proposed. The efficiency of the implemented algorithm has been demonstrated in resolving pile-up pulses with a time delay of 300 ns. Using calibrated gamma-ray sources — Am‑241, Eu‑152, Cs‑137, Co‑60, and Th‑228 — the system's energy coverage in the range of 50 to 3000 keV is confirmed. The pulse analyzer features universal architecture and is compatible with various types of gamma-ray detectors.

The article presents the results of geochronological, geochemical and isotopic studies of intrusive complexes in the central and southern parts of Rudny Altai, which until recently have been practically uncharacterized using modern research methods. The results of U-Pb dating of zircon grains from igneous rocks (26 determinations) made it possible to establish 4 stages of endogenous activity: 1) Late Devonian (~ 370–360 Ma); 2) the end of the Early Carboniferous (~ 330–320 Ma); 3) Middle–Late Carboniferous (~ 315–305 Ma); 4) Early Permian (300–286 Ma). During each stage, both mafic and granitoid magmatism was manifested, which indicates the active development of mantle-crust interaction processes. An examination of the geochemical characteristics of the studied rocks allowed us to draw conclusions about the sources of magmas and the conditions of their melting, while comparison with geological and geochronological data from neighboring regions allowed us to determine the most likely geodynamic regimes for the manifestation of intrusive magmatism in the region. In the Late Devonian, magmatism occurred in a subduction setting on the active margin of the Siberian continent. At the end of the Early Carboniferous, magmatism was associated with the onset of orogenic processes during the formation of the Zaisan folded system orogenic structure. In the Middle to Late Carboniferous, magmatic activity reflects the onset of post-orogenic extension. Early Permian magmatism is due to a combination of post-orogenic extension and the activity of the Tarim large igneous province, formed as a result of the impact of the mantle plume of the same name on the lithosphere. Special attention is given to metallogenic aspects, and suggestions are made regarding the absence of ore deposits associated with intrusive magmatism in the region..

An automatic method is proposed for counting maize seedlings under conditions of substantial weed infestation and partial occlusion using ultra-high-resolution (<0.5 cm/pixel) RGB imagery acquired from an unmanned aerial vehicle. The method is based on a combination of computer vision and machine learning algorithms. Experimental results demonstrate that the accuracy of estimating the number of maize seedlings at early growth stages averaged 97%.

A histogram scene-based algorithm is developed to compensate for gain and bias non-uniformity in infrared focal-plane arrays. The statistical scene-based calibration method is proposed. Experimental results illustrating the effectiveness of the method are presented.

Issues related to the variational approach to the problem of non-parametric a priori uncertainty are disclosed is a method of converting a system of a priori stochastic differential equations, which enables to reduce the initial problem of nonlinear filtering of a multidimensional Markov process to a problem of filtering a new Markov process, characterised by a zero drift vector. The main provisions of the method of independent first integrals are given, allowing to provide the required transformation of linear systems of a priori stochastic differential equations. Filtering algorithms were constructed, in which the method of transforming multidimensional densities is used to restore the initial a priori and a posteriori densities of the probability distribution. An example of filtering the phase of a narrowband random process using the proposed conversion method is given. It has been shown that the proposed method of transformation using numerical integration reduces the requirements for the selection of parameters of the posterior density of the probability distribution of the vector of filtered parameters

The article discusses algorithms and neural network models for semantic segmentation of the Amur River water surface areas obtained using aerial photography. A dataset has been prepared for training a neural network based on aerial photography materials of the Amur River water area. The article presents the results of research on the accuracy of prediction of the most popular models in the field of semantic segmentation, such as UNet++, DeepLabV++, FPNet, and SAM. The experiments used the IoU (Jaccard similarity measure) and Boundure IoU (object boundary segmentation accuracy assessment) metrics. Computational experiments were conducted to measure the accuracy of the trained models in order to select the optimal parameters. As a result, it was found that the UNet++ model has an advantage in terms of segmentation accuracy, with an average Boundure IoU score of > 0.9. The developed algorithms and trained neural network models can be used in river water surface monitoring systems based on orthophoto images to determine the boundaries of the coastal zone.

The superior efficiency of the piecewise linear approximation method based on Delaunay triangulation has been demonstrated. This method completely eliminates negative concentration values on the resulting surface and exhibits the most favorable gradient distribution, with only 3.33% of gradients exceeding 75 ppm across the entire point cloud surface. The significance of the obtained results lies in the confirmed ability of this approximation method to generate highly reliable and physically accurate regime maps. These maps are essential for predicting critical emission levels, such as carbon monoxide (CO) and nitrogen oxides (NOx), during liquid hydrocarbon fuel combustion, enabling the development of effective burner optimization strategies to minimize environmental impact and maximize combustion efficiency in practical power installations.

Modern trends in underwater robotics development are focused on creating fully autonomous unmanned underwater vehicles (UUVs) equipped with multi-link manipulators (MLMs) and capable of performing complex research, manipulation, and technological operations in dynamic and uncertain underwater environments without direct operator involvement. The key challenge in UUV implementation is the generation and adaptive real-time adjustment of control programs based on data about the current environmental conditions obtained from the UUV's onboard sensors and MLM sensors. This paper presents a comprehensive set of tools for an intelligent UUV mission planner, including its information and software components, as well as development methodology. The proposed planner provides decomposition of strategic tasks into elementary operations with dynamic selection of their execution sequence and parameters depending on actual data and external conditions. The architecture of the developed software is based on principles of modularity and scalability, allowing the system to be adapted for various classes of UUVs and mission types. The presented solution contributes to the advancement of autonomous UUV control methods and can be used in designing advanced robotic systems for marine research, monitoring, and underwater technological operations.

This work is devoted to the study of acoustic phonon scattering in aluminum nitride (AlN) thin films grown by magnetron sputtering with an emphasis on their potential application as piezoactive layers for microwave resonators. The main objective of the work is to establish a correlation between the data obtained by various analytical methods, including Mandelstam-Brillouin scattering (MBS), Raman scattering (RS), infrared (IR) and terahertz (THz) spectroscopy, as well as X-ray diffraction (XRD), to assess the quality and homogeneity of AlN films. The data analysis confirmed the high stability of the MBS peaks in the studied films. It was found that the stability of the MBS phonon peak reaches 87.6 ± 0.5 GHz, which corresponds to the literature data, and confirms the homogeneity of the films with an error of less than 1 %. The presence of a specific peak in the XRD patterns and the minimum width of the phonon peak obtained by Raman and FTIR spectroscopy confirm the possibility of using these methods to characterize such micron-thick films. Considering that the peak frequency of the phonon resonance did not change for films with a thickness of 4.5 μm, it is assumed that the analysis of the phonon line width may be sufficient to evaluate the grown films. The Raman method seems to be especially promising, which in the future can allow in situ analysis during the growth of AlN films. Thin AlN films with a thickness of less than 7 μm have the quality sufficient for the development of acoustic microwave resonators, which opens the way for the experimental creation of multilayer structures with different acoustic impedances based on the obtained data.

In this work, the interaction of terahertz radiation with thin ITO films (< 300 nm) deposited on fused silica substrates was studied. The complex refractive index of the films was measured in the range of 0.2-1.2 THz. It was found that the Drude model accurately describes the dielectric properties of the films in this region. The parameters of the model were determined by fitting the experimental data across a wide spectral range, from millimeter to visible wavelengths. A linear correlation between conductivity and thickness of the film was revealed. The result is valuable for the design of antireflective coatings for terahertz radiation applications. The studies on the effects of intense terahertz radiation with peak and average intensities of up to 2 MW/cm² and 1.2 kW/cm², respectively, showed the absence of laser-induced damage to the films and made it possible to outline the scope of ITO films' application as dichroic mirrors in transport channels for intense terahertz beams.