External Contour Research Articles

АРАМИДНЫЕ ОРГАНОПЛАСТИКИ ДЛЯ ПОВЫШЕНИЯ ПТИЦЕСТОЙКОСТИ ЭЛЕМЕНТОВ АВИАЦИОННЫХ КОНСТРУКЦИЙ

The possibility of using protective screens made of aramid organoplastics to ensure the bird resistance of carbon fiber wing flaps is investigated. Aramid organoplastics were selected for the production of a protective screen, taking into account the main requirements for the materials of external contour of the aircraft wing. The result of impact tests simulating the collision of a bird with carbon fiber flaps that are not protected and protected by organoplastics are presented. The optimal ratio of aramid organoplastics as part of the protective screen for carbon fiber wing flaps is presented.

Methodological diversity in Russian sociology: An analysis of research on values

Methodological diversity is a condition for the development of sociology since the complexity of social reality does not allow adhering to one universal scientific paradigm. At the same time, the nature of methodological diversity in research is an indicator of the alignment of forces of agents in the field of science. Hence the research question arises — how is the influence of the external contour of science (business, public organizations, media, politicians, etc.) manifested in the methodology used by the authors of highly cited articles on values? The work is of qualitative design and the empirical base was formed by the texts of 42 of the most cited Russian articles on the issues of values posted on the RSCI platform in 2016–2019 and indexed by international scientometric databases (Scopus, Wos CC). The choice of articles on the study of values as an empirical object for assessing the nature of methodological diversity in sociology is explained by the complexity and multilevel nature of this phenomenon, and the existence of various approaches to its study, which provides ample opportunities for various methods and techniques. The research optics was the structuralist concept of the inner and outer contours of science. Analysis of the texts of articles showed that the quantitative methodology dominates (29 out of 42). In these studies, the signs of the pressure of the outer contour of science are most pronounced. The least pressure is experienced by authors of works in qualitative design, but there are very few studies in the sample of highly cited articles (2 out of 42), and the topic of values in them is optional. Promising areas for the continuation of the research are related to the analysis of the phenomenon of imitation in the process of producing scientific knowledge and its impact on methodological diversity.

ТЕОРЕТИЧЕСКИЕ ОСНОВЫ СОЗДАНИЯ «КАРКАСНОЙ» ГЕОТЕХНОЛОГИИ ПОДЗЕМНОГО ОСВОЕНИЯ НЕДР

A physical model of the process of underground ore mining is substantiated and it is shown that ensuring the geomechanical safety of subsurface development is associated with the technological capabilities of nature-like mining technologies for the reproduction of stable dy-namic structures in the lithospheric objects being worked out. A cognitive analysis of typical geotechnologies is carried out and it is shown that the modern geo-technological paradigm is based on the principles of combining in time the processes that generate a geomechanical dis-turbance in the lithosphere and the processes to overcome the consequences of this disturb-ance. The internally insoluble contradiction of this approach is revealed and it is shown that overcoming this contradiction opens up a very real prospect of creating a fundamentally new concept for the development of underground mining technologies based on the implementation of the global idea of nature-like technologies in the form of the concept of creating convergent mining technologies. With the use of the proposed and developed by prof. The Rodionov model of the lithosphere as a solid body with different-scale inhomogeneities performed a theoretical study of the features of the stress field development during the formation of inhomogeneities with variable volume and zero density and found that in this case, the conditions for the repro-duction of stable dynamic structures will be determined by processes on the external contour of inhomogeneities. This made it possible to substantiate the geophysical and geotechnological ideas of a new technological paradigm of subsurface exploration.

On one condition for the development of an isolated defect

In the case of a plane stress-strain state, a thermodynamically complete energy condition for the development of an isolated defect is obtained, generalizing the classical condition of A. Griffiths, for the case when destructive loads are applied both to the external contour of the body and to the contour of the isolated defect. This problem arises when modeling hydraulic fracturing of an oil reservoir under the influence of lateral pressure. Taking into account the entropy component of the released internal energy in the proposed brittle fracture condition determines the dependence of critical loads on the characteristic dimensions of the isolated defect, which takes into account the temperature and the linear coefficient of thermal expansion of the material. The A. Griffiths condition does not explicitly take into account the temperature and the linear coefficient of thermal expansion of the material and follows from the proposed condition if the entropy component of the internal energy is neglected.

Advanced dose calculation algorithm in superficial brachytherapy - the impact of tissue inhomogeneity on treatment plan dosimetry.

PurposeGiven tissue inhomogeneity and lack of backscatter media, superficial brachytherapy necessitates more accurate dosimetry than TG-43 formalism. However, the introduction of modern model-based dose calculation algorithms into clinical practice should be carefully evaluated. The aim of this work was to compare dose distributions calculated with TG-43 and advanced collapsed cone engine (ACE) algorithms for individual multi-catheter moulds, and investigate the impact of target size and the lack of bolus to differences between plans.Material and methodsEleven treatment plans for individual mould multi-catheter high-dose-rate brachytherapy (IMM HDR) were selected for retrospective analysis. All treatment plans were initially calculated with TG-43 formula and re-calculated using ACE algorithm. Plan re-calculation with ACE was repeated for each plan in order to assess the impact of bolus. To evaluate differences between TG-43 and ACE dose distributions, dose-volume histogram (DVH) parameters for each ROI were compared. Dmax (maximal point dose), D0.1cc, and D2cc were calculated for each risk’s organ (OARs) and for external contour. For clinical target volume (CTV), D98, D90, D50, CTV coverage (CTV-V100), and dose delivered to reference point were compared between the plans.ResultsA significantly lower values (p < 0.05) of CTV parameters were observed for treatment plans calculated with ACE algorithm comparing to TG-43. Further analysis showed that differences between CTV-V100 for ACE and TG-43 plans depended on CTV volume. Dosimetric parameters for OARs were significantly lower in ACE plans than those of TG-43. Only D2cc for external and D0.1cc for both eye lenses in ACE plans were insignificantly different comparing to TG-43 plans.ConclusionsResults show that differences between dosimetric parameters are statistically significant. However, their clinical relevance is still undetermined. Careful re-evaluation of the clinical results based on long-term research on TG-43 is necessary to safely introduce modern algorithms to clinical practice.

A Bfgs Method for the Problem of Building S-Shaped Curve

We consider the application of the BFGS method (Broyden, Fletcher, Goldfarb, Shanno) and its projective version L-BFGS-B for minimization of nonlinear function, which corresponds to finding solutions to a system of five nonlinear equations. Among them three equations are integral and depend on unknown parameters of integrands and unknown upper bounds for definite integrals. This system represents the problem of building an S-shaped curve in natural parameterization, which passes through the two given points with given tangents inclination angles and provides a given tangent inclination angle at an intermediate point with a given abscissa. The tangent inclination angle at the point with known abscissa is used to control the inflection point of the S-shaped curve, by which a fragment of the external contour of the Frankl nozzle is modeled.The material of the article is presented in three sections. Section 1 describes a system of five nonlinear equations and analyses its properties related to the existence of many solutions. In section 2 the optimization problem with a non-smooth objective function and linear constraints is presented, the global minima of which correspond to solutions of a system of nonlinear equations. There also is described the application of the modification of r-algorithm to find global minima of the optimization problem.Section 3 describes the application of BFGS and L-BFGS-B methods to find local minima of smooth functions corresponding to finding solutions of a system of nonlinear equations. We formulate two optimization problems with smooth objective functions and two-sided constraints on variables and describe the results of computational experiments for finding solution of the system of nonlinear equations, presented in Section 1, by S-shaped curve. It is shown that BFGS and L-BFGS-B methods are effective if the starting point is selected in such a neighborhood of the minimum point, where the minimized function is approximated fairly accurately by a convex quadratic function.Manuscript received 15.06.2020

Stress-strain state cylinder-plate-cable-stayed roof buildings (structures) with various forms of external support contour

Relevance. A new wave-like combined (complex) coating design for large-span buildings - a cylinder-plate-cable-stayed roof, combining three types of structures: a cylindrical shell of zero Gaussian curvature, plate and cable-stayed (hanging) roofs are presented. This combination of structures and materials for roof large areas was not chosen by chance. The cable works in tension with its entire cross section only, and the cylindrical shell and plate work in two (longitudinal and transverse) planes. In combination with external influence, they create the necessary design strength, taking into account, at the same time, a rational choice of materials (steel and reinforced concrete). New architectural and constructive solutions of a large-span building with a cylinder-plate-cable-stayed roof are proposed taking into account the different geometric shapes of the external support contour in a form of a semicircle, semiellipse, etc. The aim of the work is to analyze the influence of the external support contour (semicircle, semiellipse, and other forms) on the spatial work of internal forces in the combined cylinder-plate-cable-stayed roof of a large-span building. Methods. Results of static numerical analysis of spatial models of large-span buildings with different types of external supporting contour in the centralized roofs were made in the FEMAP with NX NAS-TRAN software package. This complex belongs to the CAE - class which implements the finite element method (FEM) and allows on the basis of the physical and geometric nonlinearity of the deformation of structures. Results. Calculation study carried out comparative numerical analysis of the stress-strain state of a complex cylinder-plate-cable-stayed roof with different outlines of the support contours on the effect of vertical loads. This determines their rational choice given due consideration to the total cost and useful area of the building. The results of calculating large-span buildings with cylinder-plate-cable-stayed roofs for horizontal (wind) load, on the basis of determination of aerodynamic coefficients, are supposed to be published in the next article.

Diagnostic accuracy of hysteroscopy, ultrasound and magnetic resonance imaging in detecting congenital uterine anomalies.

Congenital uterine malformations occur as a result of a defective uterine development. The formation of the uterus is a dynamic process that culminates after completing four phases (differentiation, fusion, migration and canalization). Because is an evolutionary process, the resulting uterine malformation is different depending on the uterine formation phase in which the failure occurs. To establish a correct diagnosis of uterine malformations, it is necessary to evaluate both the shape of the uterine cavity and the external contour of the uterus. In this review we will describe the imaging modalities used in current clinical practice for the evaluation of the patient with suspected congenital uterine anomalies. The current role of each modality is described.

Rational installation choice of heat pump outer duct

Problem statement. The use of renewable energy sources by the world community is considered as one of the most promising ways to solve the growing problems of energy supply. The presence of an inexhaustible resource base and the environmental friendliness of renewable energy sources are their defining advantages. Given the significant potential of renewable energy sources in Ukraine, which is many times higher than the predicted levels of heat energy consumption, the withdrawal of alternative energy sources to a cost-effective level and the expansion of areas of use is an urgent issue of our time. Purpose of the article. is an in-depth study of alternative energy sources and methods for the efficient use of energy resources, followed by the selection of rational technology for constructing a heat supply system for a residential building based on geothermal energy sources. Analysis of recent research. According to the Organization for Economic Cooperation and Development (OECD), Ukraine has the highest level of utility costs in relation to income levels among European countries. The cost of Ukrainians to pay for housing is close to 40%, which is 1.6 times higher than the European average. To ensure a low level of energy consumption in energy efficient homes of the new generation, European countries use technologies that use geothermal energy through ground heat exchangers. However, this technology has not become widespread in Ukraine or enshrined in law. Therefore, the issue of introduction of technologies of ground heat exchangers at the expense of renewable energy sources is actual. Conclusion. The methods for arranging the external contours of the heat pump are considered and showed that the laboriousness of the device of heat exchangers in the horizontal circuit is almost 4 times lower than during drilling operations. The cost is also almost 4 times lower. Despite this, the developer will not always choose a horizontal heat exchanger, since for its construction it is necessary to provide a significant territory that cannot be given away for development or temporary, commercial buildings. In the case of tight construction conditions, an energy-efficient pile with a heat exchanger circuit will be acceptable.

The research of thermoelastic deformation models with thin elliptic boundary contours plates and accounting uncertainty factors

Consider thin plates with external or internal boundary elliptical contours. It is necessary to take into account the scattering errors of the values of the initial physical, mechanical and geometric parameters based on the use of the heuristic principle of generalization. Known research methods for such systems based on the methodology of accounting for plate deformation under the influence of thermometric factors. Of particular interest is the assessment of the endogenous characteristics of the process using a hybrid technology for accounting for displaying the variability of inputs to these characteristics. Significant relationships of low-variant versions of the model are created for the base component, which is a homogeneous orthorhombic area of nonzero thickness and nonzero area in given coordinates. Axes passing through the middle of the element are defined. Half shafts define an elliptical contour. Stresses in the element are generated by the heat flux, which is symmetric and axial with respect to the coordinate system in the heat flux part.

Constructing the External Contour of the Frankl Nozzle Using S-Shaped Curves with Quadratic Distribution of the Curvature

Constructing the External Contour of the Frankl Nozzle Using S-Shaped Curves with Quadratic Distribution of the Curvature

Numerical and experimental analysis of the structural performance of AM components built by fused filament fabrication

This work analyses the performance of parts built by Additive Manufacturing (AM) using fused filament fabrication (FFF) demonstrating the correlation between the printing orientation and structural performance. FFF components present two regions showing different mechanical behaviour: the external contour and the inner structure (in-fills or lattice). The respective mechanical properties of the contour and the inner structure are obtained. In this work the inner structure is replaced by an anisotropic homogenized material. A Representative Volume Element with Periodic Boundary conditions is adopted to obtain the corresponding equivalent constitutive tensor. On the other hand, the contour is considered isotropic. The material characterization of both the in-fill and the contour is done following two complementary strategies: (1) an experimental campaign involving several tensile tests on FFF specimens; (2) a sensitivity analysis through numerical modelling. Performing experiments to obtain the material properties for contour and in-fill may be a challenging task. Thus, the numerical modelling and the optimization technique are used to obtain the material properties as a function of the filament properties. Calibration of the structural response of 3D-printed demonstrators under bending and torsion is done in order to optimize the material parameters of the numerical model by minimising the difference between the experimental and numerically computed structural stiffness. It is shown that assuming isotropic behaviour for the contour results in a negligible error. The AM software so calibrated can be used for analysing the mechanical performance of FFF components and selecting the optimal printing orientation as well as the contour thickness and in-fill density to satisfy the structural performance required.

Fractal dimension of phylogenetically different parts of the human cerebellum (magnetic resonance imaging study)

In recent years, fractal analysis has been increasingly used as a morphometric method, which allows to assess the complexity of the organization of quasi-fractal biological structures, including the cerebellum. The aim of the study was to determine the value of fractal dimension of phylogenetically different parts of the cerebellum by studying magnetic resonance imaging of the brain using the method of pixel dilation and to identify gender and age characteristics of individual variability of fractal dimension of the cerebellum and its external linear contour. The study was performed on the magnetic resonance images of the brain of 120 relatively healthy patients in age 18-86 years (65 women, 55 men). T2 weighted tomographic images were investigated. Fractal analysis was performed using the method of pixel dilation in the author’s modification. Fractal dimension (FD) values were determined for cerebellar tomographic images segmented with brightness values of 100 (FD100), 90 (FD90) and in the range of 100-90 (FD100-90 or fractal dimension of the outer cerebellar contour) in its upper and lower lobes, which include phylogenetically different zones. The obtained data were processed using generally accepted statistical methods. The average value of FD100 of the upper lobe of the cerebellum was 1.816±0.005, the lower lobe – 1.855±0.005. The average value of FD90 of the upper lobe of the cerebellum was 1.734±009, the lower lobe – 1.768±0.009. The average value of FD100-90 of the upper lobe of the cerebellum was 1.370±0.009, the lower lobe – 1.431±0.008. All three values of the fractal dimension of the lower lobe, which lobules have a lower phylogenetic age, are statistically significantly higher than the corresponding values of the fractal dimension of the upper lobe, have a more pronounced correlation with age than in the upper lobe. The developed research algorithm can be used to assess the condition of the cerebellum as an additional morphometric method during magnetic resonance imaging study of the brain.

Influence of wire-arc additive manufacturing path planning strategy on the residual stress status in one single buildup layer

In recent years, the significant residual stress in the wire-arc additively manufactured components has been continuously one of the most concerning issues for the further development of the wire-arc additive manufacturing (WAAM) technology. Although many pre/post processing methods have been proved capable of modifying the residual stress, few works have been conducted to reduce the residual stress using appropriate path planning. In the present research, a WAAM path planning strategy is developed combining both zigzag and contour-offset methods, which aims to obtain a single WAAM deposition buildup layer with both optimal outline accuracy and residual stress status. The path planning and residual stress measurement processes have been carefully designed to acquire reasonable results. According to the residual stress results measured using X-ray diffraction method, the arc deposits finished with more contour-offset paths contain smaller tensile residual stresses, which is due to the hooping function of the outer contour deposit path to the inner deposit. Therefore, it can be concluded that the offsetting of the external contours before zigzag filling the internal dimensions is beneficial to both the residual stress distribution and shape outline accuracy of the WAAM buildup layer.

Minimal Aortic Injury: Mechanisms, Imaging Manifestations, Natural History, and Management.

Over the last 2 decades, increased depiction of minimal aortic injury (MAI) in the evaluation of patients who have sustained trauma has mirrored the increased utilization and improved resolution of multidetector CT. MAI represents a mild form of blunt traumatic aortic injury (BTAI) that usually resolves or stabilizes with pharmacologic management. The traditional imaging manifestation of MAI is a subcentimeter round, triangular, or linear aortic filling defect attached to an aortic wall, representing a small intimal flap or thrombus consistent with grade I injury according to the Society for Vascular Surgery (SVS). Small intramural hematoma (SVS grade II injury) without external aortic contour deformity is included in the MAI spectrum in several BTAI classifications on the basis of its favorable outcome. Although higher SVS grades of injury generally call for endovascular repair, there is growing literature supporting conservative management for small pseudoaneurysms (SVS grade III) and large intimal flaps (>1 cm, unclassified by the SVS), hinting toward possible future inclusion of these entities in the MAI spectrum. Injury progression of MAI is rare, with endovascular aortic repair reserved for these patients as well as patients for whom medical treatment cannot be implemented. No consensus on the predetermined frequency and duration of multidetector CT follow-up exists, but it is common practice to perform a repeat CT examination shortly after the initial diagnosis. The authors review the evolving definition, pathophysiology, and natural history of MAI, present the primary and secondary imaging findings and diagnostic pitfalls, and discuss the current management options for MAI. Online DICOM image stacks are available for this article. ©RSNA, 2020.

A new approach to the design of suspension roof systems

Over the last century, the suspension roofs design has progressed until the advent of the shells theory in the first half of the 20th century, due to a rapid pace in technological advancement. A paradigm shift emerged with the new trend in structural design towards a new design process that cooperatively integrated economy, efficiency, and elegance. Different approaches in computation, design and reliability assessment of roof structures are discussed in this work to identify the key conditions that have significantly contributed to modern suspension roof design principles. A new algorithm to assess the reliability of suspension roofs at the design stage is proposed and a novel method for computational design and reliability evaluation of suspension roofs is presented in this paper. The proposed method provides solutions for the following problems: obtaining rational geometric parameters of a structure; finding appropriate rigidity characteristics of basic supporting elements; determining the elements failure trajectory for typical roof diagram with the following evaluation of stress - strain state of a structure; calculating numerical safety indices of a structure (determining the lower and upper safety limits). The method enables to find the zones, where failure will be initiated. It offers an opportunity to create additional strength and reliability of structures, located in dangerous places, such as bearing joints of the connecting trusses to external contour and internal contour, the braces to the lower chord of the trusses, intermediate joints of upper and lower chords of supporting trusses etc., at the stage of design and construction. Large-span roofs have increased liability level, since their failure can lead to severe economic and social consequences. In this case, the design of these unique structures should be based on complex approach for selecting the rational structural concept related to the structure’s function, architectural concept, manufacturing methods, construction, etc. Reliability requirements, adaptability to manufacture, economic efficiency, ecological and social factors should be also fulfilled. Young engineers should be inspired by the great structural forms of the past and be encouraged to study more works from our generation to spark improved designs in the future. Based on the above, we can recommend to young researchers the universal algorithm, based on: - preliminary computation; - analysis of survivability; - design according to the limit states requirements; - design based on the numerical reliability indicators. It will allow improvement of computation methods quality and more accurate analysis of roof structures. Using this approach also leads to increasing of reliability and durability of such types of structures and minimizes mistakes in designin and computation.

Fetal thymus in the middle and late trimesters: Morphometry and development using post-mortem 3.0T MRI.

The present study aimed to investigate the anatomical microstructure, features and signals of the fetal thymus by 3.0T FS-T2 weighted turbo spin echo sequences, which could provide imaging evidence for the evaluation of early-stage development of fetal thymus. In addition, the T2-weighted three-dimensional (3D) sequences and the 3D processing may contribute to the establishment of reference ranges for the fetal thymus. A total of 64 specimens obtained from the fetuses of 16-39 weeks of gestational age (GA) were scanned by 3.0T MRI. Morphological changes and quantitative measurements of the fetal thymus were assessed, including the anteroposterior diameter, width, height, surface area and volume. The shape of fetal thymus varied and the majority were X-shaped, with a narrow top and wide bottom. Morphology measurements demonstrated gradual growth with increasing GA. There were high linear correlations between width, height, surface area and volume and GA. No significant differences were observed between the sexes. Post-mortem 3.0T MRI clearly demonstrated changes in external contours and internal structure with GA. The images and data obtained reflect normal development of the fetal thymus and enrich the imaging data of fetal morphometry.

Dosimetric Effect of Truncation on Palliative Patients

Current practice has VMAT palliative spinal patients simulated with arms tight by sides and an additional requirement of obtaining the patient’s full external contour on the planning CT. Truncation may occur due to the size of the CT bore and patient habitus, leaving the planner unable to calculate dose delivered through arms and eliminating VMAT as a treatment planning option. The purpose of this study was to assess whether significant dosimetric changes in target volume and organs at risk were observed in palliative spinal patients exhibiting simulated truncation.

SEARCH AND ELIMINATION OF REPEATED CONNECTIONS IN THE SCHEME OF GUIDING SLIDE-CRANK MECHANISM OF THE GRIPPING DEVICE

Purpose. The article is aimed to carry out a structural analysis of the coupled straight-guiding crank-slide mechanism of variable structure gripping devices with external unilateral constraints. It is also necessary to determine the number of internal and external repeating connections in the contours of the mechanism at different stages of its functioning, to assess their possible perniciousness and to suggest ways to reduce them. Methodology. Achieving this goal is carried out based on the universal structural theory of Ozols mechanisms for analyzing the gripping device as a mechanism with geometric, internal and frictional holonomic external constraints. Ozols internal and external structural formulas are used. Findings. The eleven-link gripping device is built on the basis of coupled central parallelogram crank-slider mechanism with a driving cranks. Synchronous driving cranks act on elongated connecting rods connected to sliders and gripping clamp elements. Gripping clamp elements carry out plane-parallel movement. Structural analysis was performed using structural schemes for two states of the mechanism: before clamping the object and in the state of the clamped object. In the first state of the mechanism with kinematic pairs of class V, the one-movable scheme contains thirteen internal redundant constraints. In the second state of the mechanism, external constraints act and in the scheme another five additional external repeating constraints are formed. Their contour arrangement and possible consequences of their action are shown. Originality. Structural analysis of the coupled crank-slider mechanism of the gripping device as a mechanism of a variable structure with internal and external connections is carried out for the first time. It is performed contour analysis, search and elimination, as well as reduction of pernicious repeated connections in the internal and external contour of the mechanism. Practical value. Practical recommendations have been developed on changing the mobilities of sliding pairs to eliminate all repeated connections in the internal contours of the mechanism. To reduce the number of pernicious repeated connections, the introduction of a self-centering unloading coupling into the external contour of the mechanism is proposed.

ВЗАИМОВЛИЯНИЕ ИЗМЕНЕНИЙ В СИЛОВОЙ УСТАНОВКЕ И В ГЕОМЕТРИИ КРЫЛА У ЛЕГКИХ ВОЕННО-ТРАНСПОРТНЫХ САМОЛЕТОВ

An analysis of the main directions of the development of military transport aircraft (MTА) showed that, as applied to light military vehicles, a tendency to increase their carrying capacity in a narrow range corridor was revealed. The required increase in carrying capacity inevitably entails an increase in the starting mass of modifications, which leads to a deterioration in take-off and landing characteristics, and acts as a serious limitation, especially for light military-technical complexes, according to their conditions of basing. The solution of such problematic problems can be carried out using profound modification changes in the system of load-bearing surfaces of the modification, and also in its power plant, the scientific basis for the coordination of which is based on three principles: continuous growth of performance modifications; geometric rearrangement of the wing, taking into account its ellipticity coefficient; coordination of the parameters of the power plant with an increased load capacity of the modification and with the modified geometry of its wing. The development of such models is based on the use of the weight balance equation, taking into account the fact that the components of the starting mass are not statistically determined, but there are functions of target parameters, such as load capacity, range, speed characteristics, parameters of marching engines, etc. Taking into account restrictions on take-off weight, load capacity, take-off length, etc., models were obtained for evaluating the “load-range” characteristics of light military-transport vehicles, as well as the take-off value for one engine that failed. The performance assessment of the obtained models was tested on modifications of the domestic An-26, An-32, and An-32B aircraft by evaluating their “load-range” characteristics when replacing their marching engines with increased power. An analysis of these dependencies showed that the process of matching the wing parameters and changes in the power plant (with the same external contours) leads to a significant increase in carrying capacity, and hence, flight performance. An analysis of the comparative assessment of the parameters of the basic version of the An-26 with its modifications An-32 and An-32B also revealed that the matching models obtained in the work allow already at the stage of preliminary designing more productive modifications to form their main parameters that meet the requirements of the customer.