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V. G. Khomchenko, E. G. Kholkin
Kinematic synthesis, analysis and conditions of the motion transmission in clutch-free presses at the idle mode
DOI: 10.25206/1813-8225-2026-198-5-12
The article proposes a refined two-stage method for synthesizing a third-class lever mechanism for the implementation of the idle operation of a clutch-free mechanical press, which guarantees the assembly of this mechanism at full angle of rotation of the input crank. The first stage determines the upper extreme position of the slider occupied during the press idle stroke, using a conditional four-bar linkage and an auxiliary coordinate system and also locations of the slider guide and the ordinate axes of the main coordinate system are found. The second stage of synthesis is conducted in accordance with design methods for mechanisms with an approximate dwell, based on the utilization of their extreme positions. The authors derive analytical relations to evaluate the magnitude of small displacements (oscillations) of the slider during the press idle stroke and the conditions of motion transmission. Moreover, the authors demonstrate the example that confirms the possibility of implementing the idle mode of operation of a mechanical non-clutch press with a third-class lever mechanism of the same parameters assuming ts synthesis for the operating mode. The research demonstrates the possibility of obtaining minor fluctuations of the working slider in the idle mode of the press and also presents acceptable pressure angle modes.
Keywords: clutch-free mechanical press, lever mechanism of the third class, idle mode of operation of the press, kinematic synthesis and analysis of the mechanism, displacement function, pressure angle
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5–12
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Yu. V. Kuznetsov, S. P. Gnatyuk, P. O. Yakovlev
Meaning and metrics of the “tone value” in printing technology and standards
DOI: 10.25206/1813-8225-2026-198-13-21
Since the early 1990s, the ISO Technical Committee for Graphic Technology has developed and upd ated several dozen industry standards. Almost every one of them begins with a list of definitions for terms specific to the document. To date, the series of standards accumulate a dozen variants of very ambiguous interpretations of the concept of tone value, which is the basic parameter for autotypic printing. It creates a problem of adequate translation of international standards and determines the relevance of the analysis of the currently existing contradictory interpretations, as well as the identification of the essential features of this term. In this regard, the concept and parameter "tone value" is considered in the historical context of improving models of illustration printing, considering the multi-stage nature of this process, as well as in solving the problems of color communication in the modern open and unclosed information environment. The article experimentally and analytically shows the need for more metric-adjusted interpretations and definitions of the parameter versions for a stimulus, for example, brightness Y of the XYZ colorimetric metric of the International Commission on Lighting, or to the extent of impact — lightness L from the Lab of the International Commission on Lighting. The authors establish the fact of an inappropriate percentage expression inherent in the incentive for such a perceptual parameter as the Color Tone Value, which is important for the development of versions of domestic standards based on existing international regulations.
Keywords: stimulus, perception, metrics, lightness, luminance, halftone, color management, standardization
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13–21
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T. V. Kazantseva, N. K. Kazantseva, M. A. Polyakova, V. A. Alexandrov, E. O. Paraskivaya
Quantitative assessment of the conformity level of officially assigned keywords to the standard content
DOI: 10.25206/1813-8225-2026-198-22-31
Keywords are currently used in scientific literature as one of the identifying features that helps determine the field of scientific research. Furthermore, keywords can be considered classification features for searching the required scientific information source. Keywords are essential components of any scientific source, therefore, the formulation of keywords, as well as the choice of their number, are an important aspect in developing the structure of a scientific work. The "Keywords" section has been Obligatory in the standards being developed since 1992. The search for the necessary regulatory document in existing search engines can be carried out by keywords. The aim of the research is to analyse the degree to which the formulations of keywords correspond to the content of the standards. The authors consider standards of three different classification groups from three sections of the All-Russian Classifier of Standards OK 001–2021. Moreover, the authors propose a system of indicators to quantify the effectiveness of using keywords in the title and text of the standard; conduct statistical processing of data on the keywords usage in the title and text of the standard; calculate coefficients that allow numerically assessing the situation based on the parameter whether all officially keywords are used at least once in the title or text of the standard. The research also calculates a coefficient showing the frequency of the officially assigned keywords usage in the text of the standard. The results indicate that officially assigned keywords poorly identify the standard, as a result of which the search for the necessary regulatory document is ineffective.
Keywords: keyword, standard, content, information, search, coefficient of the keyword application
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22–31
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Ju. D. Markina
Algorithm for assessing wind loads on working platforms of antenna-mast structures under conditions of digitalized engineering analysis
DOI: 10.25206/1813-8225-2026-198-32-39
The paper presents a computational approach for evaluating wind loads acting on working platforms of antenna-mast structures within the context of modern digitalized engineering workflows. The proposed method treats platform guardrails as spatial lattice systems and accounts for the individual aerodynamic behavior of each structural element. The relevance of the research is proved by the high sensitivity of antenna-mast structures to wind and by the absence of standardized procedures for calculating loads on auxiliary components, which often forces engineers to rely on simplified estimations with limited accuracy. The aim is to improve the reliability of wind load assessment for working platforms and to develop an algorithm suitable for integration into digital lifecycle support systems. The method involves elementwise calculation of projected areas, aerodynamic drag coefficients, filling ratio, and porosity-related correction factors. The algorithm is implemented in Microsoft Excel to ensure transparency, reproducibility, and seamless adoption in engineering practice. An approbation was performed on a real tower with a height of 70 m and a comparison was made with a simplified method of equivalent area. As a result, the simplified approach leads to an overestimation of the load by 5–28% and an underestimation up to –63%. Therefore, the results highlight the scientific and practical significance of the development and its prospects for implementation in complex domestic automation systems for engineering calculations of antenna-mast structures.
Keywords: towers, lattice systems, wind load, working platforms, aerodynamic coefficients, automated engineering analysis
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32–39
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Iu. O. Bredgauer, A. A. Fedorov, D. A. Polonyankin
Investigation of granulometric composition and morphology of debris particles in the context of welding bridge formation at electrical discharge machining of the stamped steel
DOI: 10.25206/1813-8225-2026-198-40-48
This article presents the results of a study of debris particles, including their elemental composition, and an analysis of the potential impact of debris particles on welding bridge formation, which can lead to short circuits and wire breakage during of welding bridge formation at electrical discharge machining of the 5NiCrMo stamp steel on a Sodick VZ 300L machine. The authors use the scanning electron microscopy, energy-dispersive X-ray spectroscopy and the laser diffraction analysis to determine the size, morphology, shape and elemental composition of debris particles. Moreover, the authors have established that the average debris particles sizes are 25.04 ± 5.26 microns for samples from the tabletop and 20.97 ± 15.10 microns for samples from the bottom of the tub. The proportion of effective particles with a critical size (greater than 25 microns) that contribute to welding bridge formation reaches 35 % (for particles from the tabletop) and 45 % (for particles from the bottom of the tub). An elemental analysis reveals that the particle consists of zinc and copper, corresponding to the elemental composition of the electrode-tool — brass material. Therefore, the results provide a better understanding of the defect formation mechanism and suggest measures to optimise the process.
Keywords: wire electrical discharge machining, debris particles, welding bridge, short circuit, scanning electron microscopy, laser diffraction analysis, elemental composition
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40–48
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D. F. Akhunov, M. N. Semenov, A. R. Mukhametzyanov
Plasma-liquid welding of brass plates
DOI: 10.25206/1813-8225-2026-198-49-55
The article discusses the use of a plasma-liquid system with solid and liquid electrodes for welding plates of brass. The purpose of the research is to study the possibility of welding brass plates using the method of plasma-liquid welding with solid and liquid electrodes. The authors demonstrate an experimental installation for producing a welded joint, which can later be used to create industrial plasma welding installations. The research methods are presented, such as scanning electron microscopy, which allow analysing the structure of the weld, as well as checking the hardness of the alloy according to Vickers’ microhardness tester. Moreover, the authors present a detailed analysis of the voltage features, on the basis of which it is revealed that an arc discharge is involved in the welding process. The experimental results demonstrate the potential of the method and show the most optimal welding parameters (voltage not less than 500 V, current up to 120 A). The resulting weld has small gas pores, but the structure remains similar to that of the base metal. In conclusion, the authors propose the development options of the method, such as the use of a mixture of various salts and acids in the electrolyte and the use of a vacuum chamber to minimize metal oxidation.
Keywords: plasma-liquid welding, plasma systems, welding methods, electrical breakdown, sodium chloride, brass, volt-amperе features
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49–55
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N. Yu. Kapalin, O. O. Berdnikov, D. S. Rechenko
Physics and technology of the laser metal processing: Analysis of processing modes of the 12Х18Н10Т steel
DOI: 10.25206/1813-8225-2026-198-56-63
The article discusses the physical foundations of laser metalworking processes, including the features of the interaction of laser radiation with the material, the mechanisms of energy absorption and the patterns of thermal effects in the processing area. The aim of the research is to determine the rational modes of laser treatment of the 12X18H10T steel, minimizing the zone of thermal influence and improving the quality of the treated surface. The authors conduct the analysis of the processes of melting, evaporation and formation of the thermal influence zone during laser cutting of metal materials. Moreover, the authors present an overview of the main types of industrial lasers used in modern laser processing technologies, including gas, solidstate and fiber laser sources, as well as their technological features, advantages and applications. Special attention is made on the effect of processing modes on the surface quality and the size of the modified layer. The article considers the properties and functions of process gases used in laser cutting and metal plating, as well as their effect on melt removal efficiency and reduction of thermal defects. The experimental part demonstrates the laser cutting of the 12X18H10T steel with a thickness of 0.8 mm on a DMG MORI Lasertec 20 installation with varying laser radiation power. The article analyses the structure of the modified layer and the nature of the thermal effect on the material and also establishes optimal processing parameters to ensure the minimum thickness of the heat-affected zone and stable cut formation. The results confirm the high efficiency of the laser technologies usage in the processing of stainless steels and the possibility to use them for high-precision manufacturing of thin-sheet structures for aviation and machine-building purposes.
Keywords: laser processing, process physics, thermal influence zone, process gases, 12Х18Н10Т steel, experiment
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56–63
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M. F. Morgunov
Precedent-based method for predicting the features of aviation components
DOI: 10.25206/1813-8225-2026-198-64-70
The uncertainty of the initial data and the limited number of use cases significantly complicate the prediction of the features of new components of aviation technology in the early stages of development. The aim of the research is to form a method of precedent forecasting, which allow evaluating the features of the projected part of a product in conditions of a lack of a priori information and with a nonlinear relations between design conditions and target parameters. The method is based on the representation of the design situation in the form of a vector of conditions (X) and a vector of predicted properties (Y), as well as on the use of an observation protocol based on previously developed analogues. In case of a small number of precedents, the author proposes a multidimensional linear extrapolation procedure based on constructing subspaces of conditions and solutions and projecting a new design situation onto the space of known analogues. Moreover, in case of a significant sample and a nonlinear connection between input and output parameters, the author provides a neural network model based on a self-organizing Kohonen map. The article formalizes the conditions for the application of both procedures, defines their mathematical models, and determines the principles for choosing the structure of the prognostic network. The practical significance of the results lies in the possibility of using accumulated design precedents for a preliminary assessment of product properties, reducing the number of design iterations and increasing the validity of design decisions.
Keywords: optimization, product design, aviation equipment, multidimensional linear extrapolation, multilayer neural network, approximation, design and technological features
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64–70
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