Pressure-gradient method for the visualization of a wave attractor

Stepan Elistratov

Accepted: 2025-04-13

Abstract

A wave attractor, a phenomenon of self-focusing of internal/inertial waves on a closed trajectory, has recently been widely studied from different viewpoints. How-ever, there is a lack of investigations concerning its visualization. Peculiar set-ups lately studied show that conventional methods need some improvement.

Herewith, in gas dynamics, the Schlieren method, based on the density gradient, is widely used. Concerning incompressible flows, it is inapplicable; however, pressure can be considered instead density. In this work, a pressure gradient is used as a way to visualize an attractor.

Determination of Adiabatic Wall Temperature in High-Speed Gas Flows Using Infrared Thermography

Н.С. Маластовский, Н.А. Киселёв, А.Г. Здитовец, А.Ю. Виноградов

Accepted: 2025-03-21

Abstract

This paper presents a method for the non-contact determination of the adiabatic wall temperature in high-speed gas flows. The method is based on the processing of a sequence of thermograms obtained using an IR camera, within a program developed in Python 3.10. The approach demonstrated high efficiency when handling large datasets, particularly concerning minimizing temporal and computational demands. The adiabatic wall temperature was determined under both steady-state conditions, directly in the experiment, and transient conditions, through the extrapolation of the heat flux as a function of the current temperature of the examined surface. The effectiveness of this method was demonstrated in the investigation of non-mechanical energy separation in compressible gas flows.

Three-dimensional images of residual strain fields by wavelet transform method

I.V. Laktionov, E.V. Gladkih, A.P. Fedotkin, G.Kh. Sultanova, А.S. Useinov

Accepted: 2025-03-21

Abstract

The accuracy of measuring Vickers hardness values depends on image focusing both during automated determination of residual imprint diagonal lengths and during operator working. Widespread algorithms for image focusing are based on brightness and contrast adjustment. We propose a new approach based on alternative algorithms for more accurate microscope focusing system used in marking imprints after indentation. Implemented algorithms are based on variance, Laplace function and wavelet transform. We select the optimum values of the basis and transform depth when using the wavelet transform. We tested new approach on samples with poor contrast, rough surfaces, and materials with pile-ups occurred in the indentation process. Applying different focusing functions depending on focus position demonstrates a more stable performance of the algorithm with wavelet transform. We also demonstrated obtaining a fully focused frame and a pseudo three-dimensional map of the sample.

Visualization of the BREST-OD-300 RP FA assembly and inspection area using virtual reality technologies

A.O. Tolokonskiy, D.G. Kovalionok

Accepted: 2025-03-20

Abstract

Currently, virtual reality technologies are used to train specialists in the field of nuclear energy, which allow the student to directly immerse himself in the environment of his activity, to carry out training as close as possible to real conditions, without causing harm to his health. In order to manufacture a fuel assembly (FA), it is necessary to undergo a number of control settings at the production stage, confirming quality and safety. The authors proposed the development of a virtual simulator with fuel assembly control installations for the BREST-OD-300 reactor plant, such as: washing and drying fuel assemblies, monitoring the tightness of fuel assemblies, monitoring the surface contamination of fuel assemblies, monitoring the mass and inclusion of fuel assemblies in the slipway, monitoring the geometry of fuel assemblies.
This simulator was developed in the Unity environment using Oculus virtual reality glasses. The results of visualization of the inspection area make it possible to check the appearance of the fuel assembly for the presence of defects and damage, measure the mass and length of the fuel assembly, as well as check for leaks, absence of leaks and contamination.

Reconstruction of object inhomogeneity parameters by near-field measurements in microwave tomography using neural networks

A.V. Medvedev, M.Yu. Medvedik

Accepted: 2025-03-20

Abstract

The article proposes a method for reconstruction inhomogeneity parameters based on the results of near-field measurements in medical diagnostics. This is a classical inverse problem arising in various fields of science and technology. At the first stage, the problem of wave propagation inside an object is considered. A rigorous description of the problem is given both as a boundary value problem and as a volume integral equation. Next, using the numerical solution of this equation, the field values outside the body in the near zone are determined. At the second stage, using the obtained near-field values using a two-step algorithm, a search for heterogeneities inhomogeneities occurs. A specially trained neural network filters the values obtained before and after the two-step algorithm, thereby improving the quality of images visualizing inhomogeneities. Graphic illustrations of the original and restored values of inhomogeneities for the objects under consideration are presented. An experiment was conducted demonstrating the features of restoring object parameters using neural networks. The results show the effectiveness of filtering the calculated data by the autoencoder. A software package for determining the parameters of heterogeneities inside the object is proposed and implemented.

Grafix – a Networked Visualization Technology

P.A. Vasev

Accepted: 2025-02-17

Abstract

The paper proposes a technology for managing views, such as user interfaces and visualization scenes. The technology is based on network interaction. This allows implementing software components responsible for visualization in some languages and libraries, and the general layout and logical parts in others. Due to this, the project can be launched in different graphical environments (for example, web and desktop applications), attract a wider range of developers due to the use of well-known languages, and ported between different generations of graphical technologies. The paper presents a software model, describes its implementation, and provides examples.

Research and Application of Machine Vision Algorithms for Defect Detection in Additive Technologies

O.N. Tretyakova, D.N. Tuzhilin, A.A. Shamordin

Accepted: 2025-02-02

Abstract

This paper discusses solving the problem of visualizing and recognizing defects that arise during selective laser melting using machine vision algorithms. The main goal of defect recognition is to reduce the time spent on selecting the technological parameters of the additive manufacturing equipment using automation methods of analysis of results. The paper presents an approach to visualizing and detecting defects that occur during the leveling stage of the metal powder layer. A methodology for software and hardware defect detection is considered and implemented. A general approach to image processing and analysis using a conveyor method is developed. The paper also discusses issues related to layer-by-layer photo documentation of the leveling process to simplify the analysis of the causes of defects. The developed software module can detect defects at the initial stages of production, allowing the process of printing knowingly defective products to be stopped, thereby enabling faster adjustment of the technological parameters of the equipment. This approach significantly reduces the time interval spent on selecting the technological parameters of the equipment and it reduces the cost of selective laser melting by saving metal powder on printing defective products. The advantages and disadvantages of the work done and the results obtained are presented.

Contextual Fidelity Factors in Usability Testing and Their Combined Impact Upon Efficiency of Human-Interface Interaction

A.V. Yakunin, S.S. Bodrunova

Accepted: 2025-02-02

Abstract

The proposed study presents the results of an experiment on the combined effects of impact factors included in the ‘contextual fidelity’ model of user experience developed in 2011. The four groups of factors described in this model simultaneously affect user experience and shape usability of interfaces, including creating hardly predictable combinatorial (e.g., cumulative or compensatory) effects in task performance efficiency. Our study investigates the combined impact of aesthetic properties of webpage design at the micro- and macro-level of interface design and task performance of different cognitive intensities, while also taking into account the cultural belonging of given web portals. Our sample includes four Russian-language versions of large-scale Russian and Chinese media portals with varying design quality at two different levels of page layout (micro- and macro-), on which task performance is tested in two conditions, namely with and without a time limit. Thus, we co-measured the combined impact of four parameters: design quality on two levels, cultural belonging, and type of task based on time constraint – upon the user performance efficiency.
We evaluated the resulting user psychophysiological states that form under the combined impact of ‘contextual fidelity’ factors via assessing cognitive productivity and psycho-emotional strain (stress and fatigue), which were used as dependent variables. As the results of the experiment showed, differences at the macro-level of design have a stronger effect on the efficiency of cognitive processes; at the same time, the emotional states of users show relative stability. In the case of micro-level differences, the impact on users’ psycho-emotional states appears to be more significant than on cognitive processes. Small cultural differences in the formation of effects are also noted.

Visualization of former images of destroyed Orthodox churches against the background of modern reality using augmented reality technology

V.A. Nemtinov, V.F. Lisyunin, A.B. Borisenko, V.V. Morozov, Yu.V. Protasova, K.V. Nemtinov

Accepted: 2025-01-24

Abstract

Currently, virtual reality and augmented reality are among the most prospective technologies that are being implemented in many areas of human life. Augmented reality allows embedding virtual objects into real, physical world. At the same time, it uses three principles of building augmented reality: Marker Tracking, Location-Based coordinate tracking and Image Tracking. In recent years, augmented reality technology has been widely used for preservation and reconstruction of cultural heritage. This article briefly examines the history of construction, operation and destruction of three of the seventeen churches in the city Tambov that existed at the beginning of the XX century: the Church in honor of the Intercession of the Holy Mother of God, the church in the name of Archdeacon Stephen (Utkinskaya Church) and the church in the name of the Great Martyr Barbara (Varvarinskaya Church). Based on available historical materials, the authors established a connection between famous people of Russia who lived and worked in the Tambov Region in the late XIX-early XX century and often visited these cathedrals, which were genuine decorations of the city. Reconstruction of destroyed Orthodox churches of the city of Tambov was carried out in the software for visualization of architectural projects Twinmotion. The images created by Twinmotion were then used to visualize the former images of destroyed Orthodox churches on the present background of the XXI century using augmented reality technology, which provides integration of virtual objects into real, physical world. The use of modern information technologies contributes not only to restoration and preservation of historical memory of Orthodox churches, but also to development and popularization of local history and museum activities, especially among the younger generation.

3D-Cloning of Core Plug Structures: Insights and Challenges into FDM and DLP Printing Based on Microtomography Data.

R. I. Kadyrov, T. H. Nguyen, E. O. Statsenko, N.V. Kharin

Accepted: 2025-01-05

Abstract

This study explores the use of FDM (Fused Deposition Modeling) and DLP (Digital Light Processing) 3D printing techniques to create accurate replicas of core plugs from reservoir rock structures based on µCT (microtomography) scans. Due to the challenges in obtaining core plug samples for reservoir characterization, this research aims to develop a cost-effective and reusable alternative by replicating the pore structure of natural rocks for use in experimental studies. A carbonate core plug was µCT-scanned to obtain a high-resolution 3D digital model of its pore structure, which was then digitally processed to simplify its complex pore geometry for 3D printing. The model was printed using FDM with 0.2 mm and 0.4 mm nozzles, as well as DLP techniques. Both methods were evaluated by re-scanning the printed samples with µCT and analyzing their structural, porosity, and permeability characteristics. FDM printing demonstrated the ability to replicate larger pore structures, but the presence of interlayer gaps resulted in inflated porosity and permeability values compared to the original core plug, and fine pore features were inconsistently replicated across multiple prints. DLP printing, while more accurate in capturing morphology and finer details, also exhibited variability in the reproduction of small pore elements. Furthermore, cracks were observed in DLP samples due to stresses during resin curing, and the retention of residual resin in pores affected permeability and reduced effective porosity. The study highlights the limitations of both FDM and DLP methods in fully reproducing the complexity of pore networks, particularly at fine scales. The results point to the need for technological improvements in both methods to enhance the accuracy and reproducibility of 3D-printed core replicas.

Visualization of Results of Bibliometric Analysis of Scilit Platform Data on AI & Machine Learning for 2021-2023

B.N. Chigarev

Accepted: 2024-12-16

Abstract

The aim of this study was to demonstrate the ability to visualize the results of the Scilit platform's bibliometric data analysis on the topic "AI & Machine Learning" to identify publications reflecting specific issues of the topic. Data source. Bibliometric records exported from the Scilit platform on the topic "AI & Machine Learning" for the years 2021–2023 were used. For each year, 6,000 records were downloaded in CSV and RIS format. Programs and utilities used. VOSviewer, Scimago Graphica, Inkscape, FP-growth utility, GSDMM algorithm. Used services: Elicit, QuillBot, Litmaps. Results. It has been shown that bibliometric data from the open access abstract database Scilit can serve as a quality alternative to subscription-only databases. Data exported from the Scilit platform require preprocessing to make them available in a format that can be processed by programs such as VOSviewer and Scimago Graphica. The use of GSDMM and FP-growth algorithms is effective for structuring bibliometric data for further visualization. The Scimago Graphica software provides wide possibilities for building compound diagrams, in particular, for representing the network of keywords in such important coordinates for bibliometric analysis as average year of publication and average normalized citation, as well as for building an alluvial diagram of co-occurrence of more than two keywords. The possibility of using such services as elicit.com, quillbot.com and app.litmaps.com to accelerate the selection of publications on the topic under study is shown.

Two-channel high-temperature combustion imaging system based on high-speed cameras EVERCAM F 1000-16-C

F.A. Gubarev, L.Yu. Davydova, M.S. Tsiron

Accepted: 2024-11-24

Abstract

The paper presents the results of using Evercam F 1000-16-C high-speed cameras for high-speed visualization of laser initiation and high-temperature combustion of Al-CuO thermite mixture. The possibility of determining process parameters based on the results of high-speed shooting is demonstrated. Two visualization modes are considered: synchronous operation of two cameras to obtain images from two angles, and synchronous operation of two cameras as part of a laser monitor with a copper bromide vapor brightness amplifier. In the case of direct video recording, one of the cameras acts as the master one, and the recording frequency is set in the service program. It is proposed to use a two-angle video recording mode to study the spread of flame in a volume. For the first time, Evercam F 1000-16-C cameras were used as part of a laser monitor with a copper bromide vapor brightness amplifier. Laser monitoring, combined with direct video recording, makes it possible to study the surface of a sample in the area of igniting laser interaction and flame propagation in one of the planes. A feature of the operation of Evercam cameras as part of a laser monitor is the need to generate trainы of clock pulses synchronized with the radiation pulses of the brightness amplifier and the radiation pulse of the igniting laser. In this case, both cameras work in slave mode. The synchronization unit is designed using the STM32F103C8T6 microcontroller board and has galvanically isolated input and output signals.

Development of a Programmable 16-Frame Electron-Optical Camera NANOGATE-22/16 and its Application for Measuring the Space-Time Characteristics of Fast-Flowing Processes in Ballistics and Explosion Physics

S.I. Gerasimov, M.I. Krutik, V.S. Rozhentsov, D.Yu. Smirnov

Accepted: 2024-11-24

Abstract

The paper presents the main technical characteristics and results of the application of the programmable electron-optical camera NANOGATE-22/16, developed at NANOSCAN LLC, Moscow. The frames of characteristic experiments from the field of explosion physics are presented. The electron-optical camera is an 8-channel system consisting of one input lens, a mirror-lens unit for dividing the image into eight channels (an additional lens, an octagonal mirror prism, eight mirrors) and the electron-optical channels themselves (K-1, K-8). The data obtained as a result of recording images of a fast-flowing process is transmitted through eight fiber-optic communication lines to a transceiver that converts signals at eight optical inputs into a signal at a single USB-3 output, which is connected to the corresponding computer input. All 16 registered images are visualized on the computer monitor. The dust- and moisture-proof housing of the electron-optical camera provides the possibility of its use in landfill conditions.

Isotropy in Local Computer Geometry

A.V. Tolok, N.B. Tolok

Accepted: 2024-11-18

Abstract

The article discusses the property of isotropy in local computer geometry. The basic principles of applying such a property in the representation of computer data about the domain of a function are demonstrated using the example of a function of two arguments. The scope of application of the isotropic property in algebraic transformations, data packing and encoding is considered. The effect of isotropy in algebraic transformations is given using the example of the product of two functions. The formation of the domain of local functions of the paraboloid surface for describing a circle is illustrated on the basis of the domain of local functions for describing the surface for a square. The possibility of computer representation of the domain of local functions by a single graphical M-image is analyzed.

Application of PyTorch3D and NERF Computer Vision Tools for Building a Point Cloud of a Three-Dimensional Model and Determining the Camera Position of Still Images in Space

V.V. Konkov, A.B. Zamchalov

Accepted: 2024-10-03

Abstract

Recently, computer graphics plays a key role in solving computer vision problems. The problem of converting 2D images into 3D models continues to be urgent, as it requires precise determination of camera position and construction of accurate 3D models of objects. Traditional methods are often limited in application and do not offer a comprehensive solution. This study examines the use of PyTorch3D and NERF libraries to determine the camera position in 3D space and create a 3D model of an object from a single 2D image. As a method of data preparation, a hardware and software system was used, including a stepper motor control device that provides manual and sequential positioning of the camera and its return to the initial position, a shooting control system to generate a comprehensive set of photos at each camera position, and a mechanism for sending data to a remote computer for further processing. The PyTorch3D library was selected during the study to explore the possibilities of converting 2D images into 3D models or determining the position of an object in the photos. The processing process included several steps: building a point cloud to generate a 3D volumetric model of the object, determining the camera position in 3D space from a single 2D image using inverse problem algorithms, and constructing a 3D object using differentiable rendering, creating 3D voxels and 3D meshes. The results of this study showed successful determination of camera position in 3D space and construction of a 3D object model from a single 2D image, demonstrating the advantages of using the PyTorch3D library over other existing models. These findings can be applied in the development of software and hardware systems for creating 3D images from 2D photographs. The study confirmed the relevance and effectiveness of using PyTorch3D library to solve the problems of converting 2D images into 3D models. Further work will be aimed at expanding the functionality of the system and its use in various areas of computer vision.

Visualization of methods of machine learning. GUI programming

Accepted: 2024-09-24

Abstract

The technologies of artificial intelligence and machine learning have made a fundamental leap in their capabilities in the last five years. The growth of processing power and the emergence of more and more effective methods of machine learning allows AI to not just solve the most typical tasks associated with the field, such as statistical analysis and optimization of mathematical processes, but also to find new applications in related fields of research, as well as practical applications, including those on the free market, available to the mass consumer. Image generation, audio, animation, self-learning models of control of robotic platforms and virtual mechanical models – these and many more novel applications of the recent years have led to a media-boom around AI and a growing interest from developers and authors from various fields and industries.
That being said, the methods for developing, research, testing, and integration of AI have largely remained unchanged and still require the knowledge of programming languages, machine learning libraries, as well as a deep understanding and experience specifically in the narrow field of AI. This barrier of specialization not only demands inclusion of machine learning specialists in the development process of otherwise trivial computer applications, typical for the field of AI, but also prevents small teams and independent developers from using the latest advances in these technologies without significant monetary and time investments into studying the subject.
We offer a novel solution to this issue in the form of a prototype graphical interface that allows the user without technical education and without the need for knowledge of programming languages to develop and tune various architectures of neural nets and other machine learning methods, methods of unsupervised machine learning, and to test these methods on a wide range of experimental tasks – from mathematical equations to controlling virtual mechanical models in a simulated physical environment. In this article, we give a brief description of its structure and organisation, its fundamental principles of operation, and the capabilities of this GUI.

Use of Hadamard matrices in single-pixel imaging

Denis V. Sych

Accepted: 2024-08-13

Abstract

Single-pixel imaging is a method of computational imaging that allows to obtain images of objects using a photodetector that does not have spatial resolution. In this method, the object is illuminated by light having a special spatio-temporal structure, — light patterns, and a single-pixel photodetector measures the total amount of light reflected from the object. The possibility of obtaining an image and the image quality are closely related to the properties of the applied patterns and computational algorithms. In this paper, we consider patterns obtained from modified Hadamard matrices and study the features of image calculation using single-pixel imaging. We show the possibility of reducing both the sampling time and the computational resources required to obtain images by modifying the pattern system. The proposed theoretical method can be used in the practical implementation of the single-pixel imaging method in an experiment.

Numerical visualization of vortex wakes behind large particles

А.А. Mochalov, А.Yu. Varaksin

Accepted: 2024-08-11

Abstract

An attempt has been made to visualize the flow formed in the wake of large particles moving in an ascending turbulent air flow in the channel. Numerical modeling was performed using a simplified version of the approach called "two–way coupling" (TWC) in English literature and taking into account the inverse effect of particles on gas characteristics. The particle motion was calculated in an approximate manner, therefore the method used is called "quasi – two–way coupling", TWC(Q). The results of numerical modeling of the characteristics of turbulent trails behind large moving particles based on the Reynolds averaged Navier-Stokes equations (RANS) are presented.

Mapping the Knowledge Base on Visual Reality Technology and the Manufacturing Industry

Geofrey Rwezimula, Zhang Guoxing, Wakara Ibrahimu Nyabakora

Accepted: 2024-08-01

Abstract

Virtual reality applications provide users with more than just realistic sight; they may also sense touch, hear, and even interact with virtual objects. With these significant advancements, virtual reality has seen recent growth surges in a number of sectors, including the manufacturing industry. It has to be successful in drawing attention from both academics and industry. It needs to be known how researchers are interested in the technology application. Therefore, examining the body of research on the connection between visual reality and the manufacturing industry is the goal of this research. The bibliometric study was carried out using the Scopus database. Using PRISMA, the sample procedure was finished. VOSviewer was utilized to search through 2,037 publications. This disclosed the expansion of the network, the most active contributing stakeholders, the backdrop of the intellectual framework, the research gap, and the greatest popular topic that needed to be filled. We observed that starting in 1992, papers pertaining to the influence of virtual reality on the manufacturing industry collected from the Scopus database were included. The words “augmented reality,” “virtual reality,” “process simulation,” “industrial internet of things,” “industry 4.0 technologies,” and “3D technologies" have been widely used since 1992. The density map's representation of contemporary themes includes “artificial intelligence” and “human-robot interaction.” The significance of the findings for researchers lies in their relevance to the past, present, and future, along with the identification of knowledge gaps.

Spectral Evaluation of the Vital State of Quercus Robur L. Under Simulated Drought Conditions

P.A. Zybinskaya, A.V. Tretyakova, P.A. Krylov

Accepted: 2024-07-24

Abstract

Non-destructive spectral methods of analysis are increasingly being used to study the content of plant metabolites, evaluate morpho-physiological and biochemical indicators, as well as evaluation of the vital state. Visualization of the vital state through spectral profiles can provide a more detailed picture of plant adaptation to stress. To model experimental drought, 5-6 month-old Quercus robur L. seedlings were divided into three groups: control and experimental groups with and without watering (drought), with 15 seedlings in each group. Spectral evaluation of leaf blades was performed using a portable spectroradiometer SpectraPen SP110 Uvis and a plant analyzer Dualex Scientific+ at 0 (control), 168 (one week), and 336 (two weeks) hours. As a result of spectral analysis, spectrograms of radiation absorption of Q. robur leaf blades were obtained, as well as the content of the sum of chlorophylls, flavonols and anthocyanins under watering and drought conditions. The study revealed changes in the spectrograms of absorption of Q. robur leaves related to the content of metabolites. The difference in absorption peaks between the groups became more expressed over time under the influence of drought. The pigment content in the leaf blades varied during the experiment, which indicates plant adaptation to stress. Preliminary results of the study can be used to expand knowledge about ways to evaluate the vital state of woody plants in the field.

On The Visualization of Subattractor Under Mixed Tidal Forcing

Stepan Elistratov, Ivan But

Accepted: 2024-05-18

Abstract

One of the principle conditions of a wave attractor appearance is a periodic external forcing. Real forcing in natural basins caused by tidal interaction is more complex than a monochromatic which is usually used in internal wave attractors investigations. Multi-frequency forcing may lead to the multiple wave attractor formation, some of them may be of low energy, which affects their detection. In the article we simulate a mixed forcing for an internal wave attractor flow and visualize subattractor formed due to this forcing type using several methods, including Proper Orthogonal Decomposition. It is shown that the latter method reveals sub-attractor even in case of highly turbulent flow.

Visualization of Turbulent Wakes Behind Large Particles

A.A. Mochalov, A.Yu. Varaksin

Accepted: 2024-05-17

Abstract

An attempt was made to visualize the flow formed in the wake of large particles moving in a downward turbulent airflow in the channel. The paper also considers the possibilities of reconstructing velocity fields behind a large particle from visual data. A diagram of the experimental setup is shown (geometry of the working area, auxiliary and main equipment). The PIV (Particle Image Velocimetry) system is briefly described. A technique for visualizing multiphase flow “gas – solid particles” is proposed. The original images of large particles (spheres) are shown. The results of the experimental determination of the characteristics of the wake vortex behind the rear critical point of a large particle are presented.