Methods Of Mathematical Modeling Research Articles

The control unit of the combined photovoltaic/thermal system

During the last years the design and implementation of energy-saving solutions remains a relevant and integral task for implementation the route of decreasing carbon emissions and reduce the negative impact on the environment. Using combined photovoltaic/thermal systems is limited by their high price connected mainly with the complexity of their control systems, even taking into account availability of government programs for financial support for the use of alternative energy. The novelty of the proposed work consists in the development of a mathematical model and the analytical study of the control system of combined photovoltaic/thermal system for research the operation of control and logic elements and their response to transient and emergency modes during such systems operation. Aim of the work - operational analysis, analytical and optimization studies of the control system of the combined photovoltaic/thermal system to ensure reliable operation in transient and emergency modes and significantly simplify the design of such a system. In this article was implemented mathematical modeling methods and using specialized software. As a result of the work the mathematical model of the control system of combined photovoltaic/thermal system which operates with variable set of control and logic elements was developed. A structural solution of the control system is proposed for further implementation and field testing. The response criteria of the control system to transient and emergency operation modes of the combined photovoltaic/thermal system have been developed. Practical value. It was established the permissible and critical values of a number of parameters characterizing the operation of combined photovoltaic/thermal system in normal mode and deviations from which indicate the presence of an emergency situation are determined. The proposed algorithms of the control system will make it possible to increase the reliability of combined photovoltaic/thermal system and reduce the risk of emergency situations during field tests and further operation.

Mathematical Modeling of Multi-Physics Phenomena in Smart Materials and Structures

Smart materials and buildings show interesting multi-physics effects, where the interaction of different physical fields like mechanics, electromagnetics, thermodynamics, and sound is very important. This essay gives an in-depth look at different mathematical modeling methods used to understand and predict how smart materials and buildings will behave in various situations. At its core, the modeling framework combines guiding equations from various physical fields. This calls for a comprehensive method that takes into account how these events interact with each other in complex ways. The basis is mechanics, which includes fundamental equations that show how materials react to mechanical forces, including elasticity, viscoelasticity, and flexibility. Electromagnetic effects are very important in materials like magnetostrictives and piezoelectrics, where the way electrical and mechanical fields combine determines how they work. To correctly describe this electrical connection, Maxwell's equations are linked to mechanical equations. This lets devices like sensors, motors, and energy harvesters be designed and improved. Thermodynamics is used for shape memory metals and phase change materials, whose behavior is controlled by changes in temperature. Adding heat transfer equations to mechanical and electromagnetic equations helps us fully understand how these materials interact with heat, motion, and electricity, which is important for many uses, from medical devices to spacecraft structures. Structures with active shaking control systems that use piezoelectric materials have interesting acoustic effects. With the help of mechanical and electrical algorithms and acoustic wave transmission models, it is possible to study and create smart structures that can reduce noise and shocks while also improving their performance and integrity. The study also talks about numerical methods, like finite element methods and multiphysics modeling tools, that can be used to quickly solve the linked equations. These tools help us learn more about how complicated materials behave in various working situations.

DriverDetector: An R package providing multiple statistical methods for cancer driver genes detection and tools for downstream analysis

Identifying driver genes in cancer is a difficult task because of the heterogeneity of cancer as well as the complex interactions among genes. As sequencing data become more readily available, there is a growing need for detecting cancer driver genes based on statistical and mathematical modeling methods. Currently, plenty of driver gene identification algorithms have been published, but they fail to achieve consistent results. In order to obtain gene sets with high confidence, we present DriverDetector, an R package providing a convenient workflow for cancer driver genes detection and downstream analysis. We develop the background mutation rate calculating module based on the distance between genes in covariate space and binomial test, followed by the driver gene selection module which integrates 11 methods, including two already recognized approaches, a de novo method, and five variants of Fisher's method which are applied to driver gene identification for the first time. Through verification on 12 TCGA datasets, each method is able to identify a set of confirmed driver genes while the number of resulting genes vary significantly across different methods. For robust driver genes detection, a voting strategy based on 10 of the statistical methods is further applied. Results show that the collective prediction based on the voting strategy demonstrates superiority in achieving the consistency of prediction while ensuring a reasonable number of predicted genes and confirmed drivers. By comparing the results of each cancer dataset, we also find that sample size has a huge impact on the number of predicted genes. For downstream analysis, DriverDetector automatically generates plenty of plots and tables to elaborate the results. We propose DriverDetector as a user-friendly tool promoting early diagnosis of cancer and the development of targeted drugs.

The effect of a textured surface in the form of triangular prisms on the occurrence and development of cavitation behind the cylinder in microchannels

Cavitation flow in a microchannel behind a cylinder with a smooth and textured surface is investigated using mathematical modeling methods. The textured cylinder has 72 triangular prisms on its surface. The height of the prism, normal to the surface of the bluff body, was 100 nm. Profiles of the flow velocity and volume fraction of vapor are constructed. The monitoring of the velocity and pressure at five points behind both the smooth and the textured cylinder was carried out, while the inlet pressure changed up to 30 bars. It is shown that there is no restructuring of the vortex street to a symmetrical form at quite high-pressure values at the inlet to the channel for a rough cylinder. Namely, roughness prevents the flow stabilization. A pressure jump in the microchannel is observed when a cavity appears with a uniform increase in the flow rate. Two pulsation frequencies are determined for each of the flow modes. The first pulsation frequency ranges from 480 to 2200 Hz and is associated with the formation of cavitation. The second pulsation frequency is associated with the hydrodynamic flow around the cylinder and its values range from 26 to 95 kHz. An increase in surface roughness leads to a growth of the cavitation pulsation frequency and intensifies cavitation. At that, the velocity pulsations in the flow before the onset of cavitation increase, and the frequency of hydrodynamic pulsations after its onset decrease. The paper provides an analysis of the drag coefficient of a hydraulic section with rough and smooth cylindrical bluff bodies. The effect of roughness on the change in the hydrodynamic characteristics of the flow is described.

Towards Green Industrial Development in Ukraine: A Decision Model for Post-Industrial Production Strategies

The issue of modelling decision-making in the field of green production in a post-industrial society determines the relevance of the study. The main goal of the study is to develop a decision-making model that can help green industry organizations identify optimal strategies and actions to reduce environmental impacts, ensure sustainable efficiency, and promote development. The methodology used in the study involved a theoretical analysis, synthesis, and mathematical modelling methods. As a result, an innovative mathematical model was developed and proposed, which allows predicting the influence of various factors when choosing the optimal production strategy. The results show that the application of the developed model allows Ukrainian enterprises in the field of green production to determine optimal strategies aimed at reducing the environmental impact of production processes on the environment. It helps to ensure sustainable production efficiency, contributing to the economic sustainability of enterprises and the global economy.

Dairy subcomplex of Kazakhstan: condition, measures to improve efficiency

The current state of production of milk and its processed products in the regions of Kazakhstan has been studied. The goal is to assess the situation on dairy market, identify problems hindering the development of the industry, and develop recommendations to increase its competitiveness. Methods – monographic, logical, systemic and complex analysis, statistical data processing, constructive-functional approach. The works of domestic and foreign economists concerning the problems of dairy cattle breeding and milk processing structures were used as theoretical and methodological basis for scientific research. Results - factors directly influencing the growth of dairy product volumes were analyzed, including their quality, profitability, operation of logistics systems (supply chain, product transportation, transportation optimization), and marketing strategies. The method of economic and mathematical modeling was used to determine the strengths and weaknesses of enterprises, as well as the opportunities and threats of the external environment. Particular attention is paid to aspects of regulation of legislative framework, as well as adaptation to changing market conditions and consumer preferences. To increase production of own high-quality milk and reduce import dependence, the state actively supports and stimulates the creation of dairy farms, increases the volume of state subsidies for agricultural producers, and simplifies lending and micro lending system. It is important to ensure increase in profitability of dairy producers, reduce the influence of seasonality on price situation of dairy market, and develop infrastructure of social nutrition system. Conclusions - it is necessary to introduce new technologies, digital transformation in livestock farming, increase in technical equipment, allowing to increase the size of gross product, level of self-sufficiency in domestic products and expand participation in foreign trade as the main form of international economic relations.

Сравнение характеристик линий высокого и сверхвысокого напряжений при выборе параметров управляемого устройства продольной компенсации

The use of series compensation devices leads to an increase of the transmission line capacity. However, it also increases the risk of an oscillatory violation of the stability of the electric power system. Cumulative hunting and self-excitation of the system is observed in the systems with controlled series compensation devices with a high degree of capacitive compensation. It is known that automatic excitation control of generators partially eliminates the negative effect of series capacitive compensation on oscillatory stability. Therefore, when choosing the tuning parameters of controlled devices, it is necessary to consider their combined effect on the system modes. The developed methods to study steady-state stability make it possible to analyze the modes of power systems with controlled power transmission of various voltage levels. Thus, it is advisable to conduct a comparative analysis of the influence of the adjustable parameters of the series compensation device on the steady-state stability of systems of various voltage levels, considering synchronous generators automatic excitation control. Methods of mathematical modeling of the electric power system, the theory of long-distance power lines and electromechanical transients, methods of analyzing the stability of electric power systems are used. The original software in the C ++ programming language has been used as a modeling tool. The choice of controlled series compensation device and the automatic excitation control regulation laws parameters is made, provided that steady-state stability is maintained. The stability regions of the studied electric power-engineering system are constructed depending on the tuning parameters of the considered devices of various voltage levels. A comparative analysis of the characteristics of the modes of high and extra-high voltage lines has been carried out. The regulation coefficients values of controlled series compensation device and automatic excitation of generators have been determined, under which there is no violation of oscillatory stability for different voltage levels. The conducted comparative analysis of the characteristics of high and extra-high voltage power lines demonstrates the need to consider the power transmission rated voltage when comprehensively selecting the tuning parameters of the controlled series compensation device and the automatic excitation control regulator.

Mathematical modeling of heat exchange for efficient automated control systems

The article deals with the problem of mathematical modeling of heat transfer processes, taking into account a large number of factors affecting these processes and a variety of mathematical modeling methods. The article discusses the idea of developing a universal and flexible model that could quickly adapt to different initial modeling conditions and take into account various parameters for further use of the mathematical model in the synthesis of automatic control systems. The paper discusses the main aspects of mathematical modeling of heat transfer and the creation of a mathematical model in distributed heat exchanger parameters with the possibility of changing the properties and parameters of the equipment. The paper analyzes previous studies and identifies the problems of existing methods of mathematical modeling of heat transfer, such as lack of versatility, complexity, and insufficient accuracy. The paper goes on to review different approaches to mathematical modeling of heat transfer, such as models with a group of parameters, models in distributed parameters, and models based on artificial intelligence. The article provides an overview of model implementation methods and their advantages and disadvantages. Based on this analysis, the authors propose a new mathematical model of heat transfer in distributed parameters, which should be universal, easy to use, and accurate in accordance with the requirements of synthesizing automated control systems. The authors also outline the methodology for achieving this goal, which includes the implementation of the geometry of the heat exchanger, the implementation of conditions and mathematical modeling, as well as the study of the influence of parameters and the formation of transients. The general conclusion of the article is that the developed mathematical model of heat transfer can be used to synthesize automatic control systems for heat exchange processes in various industries.

Предел передаваемой мощности в системе тягового электроснабжения

Objective: the concept of the limit of power flow is widely used in general industrial power engineering to compare different ways of amplifying an electric network. In this paper, it is proposed to use it to evaluate the operation of traction networks of railways. Setting the traction power load is used in several simulation development of an express methodology for comparing various ways to enhance traction power supply is an urgent task. Methods: the paper uses mathematical modeling methods based on the theory of electrical circuits. The MATLAB software package was used as a modeling tool. Results: expressions are obtained for calculating the maximum transmitted power depending on the length of the substation zone. The dependence of the transmitted power on the minimum voltage on the current collector, the equivalent resistance of traction substations for DC sections, is analyzed. For alternating current sections, the dependence of the transmitted power on the power factor of the traction load is analyzed. The conclusion is made about the relevance of increasing the power factor of an alternating current electric rolling stock. Practical importance: the proposed technique will allow you to quickly assess the effect of using various methods of strengthening the traction power supply system.

Biologically Active Terpenoids Ligularia Macrophylla (Ledeb.) DC. аnd Technology of New Drug Substance

The article presents the results of a chemical study of Ligularia macrophylla (Ledeb.) DC. The essential oil was isolated by hydrodistillation using a Clevenger apparatus and microwave extraction using a NEOS installation. Using mass spectrometry, 52 components were identified in the essential oil isolated by hydrodistillation; 63 components were identified in the essential oil isolated by microwave extraction. The main components of the essential oil are Δ3-carene, β-bisabolene, β-myrcene. It was revealed that the substance obtained from the essential oil of Ligularia macrophylla (Ledeb.) DC. has anti-inflammatory and antimicrobial activity. For the first time, the optimal technological parameters for alcohol extraction of Ligularia macrophylla (Ledeb.) DC roots were determined using the method of mathematical modeling, providing a quantitative yield of the sesquiterpene lactone furanoeremophilan-14β,6α-olide, which has anti-inflammatory activity.

TO HIGHLY PRODUCTIVE SYNTHESIS OF ALUMINUM NANOPARTICLES IN PLASMA FLOW AT ATMOSPHERIC PRESSURE

Purpose. To study the highly productive evaporation of aluminum micron powder in an atmospheric pressure plasma jet for the synthesis of nanoaluminum. Using special plasma technology, nanoparticles can be produced by rapid melting and evaporation of the initial micrometer particles and their subsequent re-nucleation. Research methods. Methods of mathematical and computer modeling of subsonic plasma turbulent jets at atmospheric pressure and experimental studies of two-phase processes during thermal plasma treatment using an arc plasma torch. Results. Based on computer modeling, a special reactor system was designed and developed, which includes a plasma-jet reactor with an electric arc plasma torch for the synthesis of aluminum nanoparticles. Numerical modeling makes it possible to determine the position of the melting point, evaporation and crushing of a molten particle, the evolution of the fractional composition of the dispersed phase, and find the speed and temperature of the particle in the area from its melting point to the crushing point. An experimental test of the operation of the reactor system was carried out using arc plasma torches with a power of 30 and 150 kW. It has been shown that intensifying the fragmentation of dispersed raw materials in a plasma jet can be useful in technologies for producing nanomaterials. The consequence of the fragmentation process is the redistribution of the fractional composition of the powder along the plasma jet and the accompanying changes in the dynamics of movement, heating and evaporation of particles. It has been determined that when the temperature of the largest aluminum particles reaches 2500 C, the total amount of evaporated mass is theoretically equal to 100%. The main parameters influencing the behavior of particles in a plasma jet are particle diameter, powder injection rate, flow rate, temperature and composition of the plasma gas. Taking these parameters into account will allow the process to operate at increased productivity. Scientific novelty. A mathematical description of the process of fragmentation a polydisperse powder, based on a continuum approach, has been obtained, which makes it possible to determine the position of the crushing point of a molten particle, the fractional composition of the dispersed phase, and find the speed and temperature of the particle in the area from its melting point to the point of crushing and evaporation. It was shown for the first time that it is possible to carry out a process in which complete evaporation of a molten drop is achieved due to the high enthalpy of the plasma before the end of mixing with steam. Practical value. A special reactor system has been designed and developed, which includes a plasma-jet reactor with an electric arc plasmatron for the synthesis of aluminum nanoparticles. The operating parameters of the reactor system have been determined, which will allow the synthesis of aluminum nanoparticles to be carried out with high productivity.

ИСПОЛЬЗОВАНИЕ МАТЕМАТИЧЕСКОГО МОДЕЛИРОВАНИЯ ДЛЯ МНОГОПАРАМЕТРИЧЕСКОГО АНАЛИЗА ЭЛЕКТРОННЫХ СХЕМ С ЛИНЕЙНЫМ АКТИВНЫМ УСТРОЙСТВОМ

It is proposed to use matrix methods for mathematical modeling of the operation of electronic analog linear devices. They allow using computational tools to obtain results with high calculation speed and acceptable accuracy. For example, a scheme of an active second-order electronic filter based on an operational amplifier is proposed. A multiparametric analysis of the transfer function based on the primary parameters of the electronic circuit is proposed. The proposed method for analyzing linear active electronic circuits based on the conduction matrix can significantly reduce the calculation time and significantly simplify the forms of writing analytical expressions. The calculation results are com-pared with the results obtained in a specialized program for modeling electronic circuits OrCAD PSpice. For example, the transfer function is analyzed according to the following parameters: sensi-tivity, statistical synthesis, optimization of tolerances

Статистическая оценка влияния антироссийских санкций на динамику развития российской промышленности

The relevance of the study is due to the unprecedented number of economic sanctions imposed on the Russian economy since 2014. In this paper we will assess the impact of economic sanctions on the development of key sectors of the Russian industry: machine-building complex, food industry and extraction of fuel and energy minerals. The dynamics of the development of the analyzed branches of the Russian industry in the 13-year time interval was multidirectional. High utilization of production capacities and support of national production by the weak national currency were counteracted by negative factors associated with the coronavirus pandemic and sectoral sanctions against the Russian economy. The study verifies the hypothesis of the negative impact of economic sanctions on the development of Russian industry using economic and mathematical modeling methods. The results of the study showed the existence of a relationship between the number of anti-Russian sanctions and the dynamics of development of two branches of the Russian industry: food and machine-building. For the mining industry the correlation coefficient was insignificant.

Метод визначення вібраційних характеристик промислового обладнання в частотній та часовій областях

This paper proposes hardware and software solutions and a data processing method for vibration diagnostics of industrial equipment, which uses discrete Fourier transform and Allan dispersion to increase the accuracy and stability of measurement processes and result processing. The object of this study is the use of vibration diagnostic methods to implement the concept of maintenance of industrial equipment based on monitoring its current and future condition. The subject of this research is the hardware and software solutions for vibration diagnostics systems and methods for processing measurement results. The purpose of this work is to develop a new resource-saving IoT-oriented wireless solution for vibration diagnostics, where the contact method and MEMS accelerometers are used to measure vibration parameters and to evaluate the effectiveness of new methods and algorithms for processing experimental data. The task: justify the need to find new hardware and software solutions and methods of processing the obtained results for the implementation of the service concept based on the tracking of vibration indicators of technical equipment; provide basic hardware and software solutions for the implementation of the cloud platform of vibration diagnostics; develop methods of processing results; check the developed methods and algorithms using mathematical modeling methods and in an on-site experiment; compare the effectiveness of own and competitive solutions; draw conclusions and formulate a plan for further research. Conclusions. It has been proven that the combination of known analysis methods in the time and frequency domains with multi-level processing gives better results than analogous methods. The developed hardware and software tools and the method of processing measurement results effectively implement the contact method of vibration measurement, which provides the possibility of tracking the state of technical equipment. The developed equipment for the calibration of vibration acceleration sensors can reduce accelerometer errors. Further areas of research are the search for the optimal distribution of calculations on IoT levels, reducing the computational complexity of algorithms, increasing the time of continuous autonomous operation of the lower-level microcontroller, creating micro services for time-series analysis, and researching the dependence of the technical state of the equipment on the calculated Allan deviation.

Algorithm of Development for Stabilization of Socio-Ecological Situation in Karakalpakstan

The relevance of developing a scientific framework for stabilizing the socio-ecological situation of the Republic of Karakalpakstan is determined by the need to address the environmental, social and economic challenges faced by the region. It is designed to improve the population’s quality of life, sustainable development and balanced interaction with the environment. The purpose of the research was to establish the relationship between social and environmental factors, to establish a mathematical model based on them, which will enable predicting future development and establishing a set of recommendations to improve the situation in the Republic of Karakalpakstan. The methods of theoretical analysis and mathematical modelling were used. The research outlines modern ideas about modelling the dynamics of socio-ecological processes in the example of the Republic of Karakalpakstan. It is established that the Republic has several problems, the solution of which should be started shortly. Considerable attention is paid to the setting of tasks and using for this purpose methods of system analysis of socio-ecological factors. In this work, the analysis of factors affecting the social and environmental environment of the Republic of Karakalpakstan using regression analysis is considered. The parameters of the developed mathematical model and their adequacy are determined. The developed mathematical model will allow identification of the social and ecological situation of the republic. At the end of the work, ten priority points for the next 5-10 years to improve the socio-ecological situation were presented. The practical value of the results is implemented in promoting the identification of new powerful reserves for further improvement of the management of social processes. This approach allows for increasing the national economic efficiency of the region and ensuring a balance between economic, social and environmental aspects of development, which is an essential step towards a sustainable future.

Modeling of Non-Stationary Mass Transfer Process in Groundwater

Purpose. Infiltration of contaminated water and accidental spills of chemically hazardous substances into groundwater lead to the formation of large zones of man-made pollution in aquifers. Therefore, it is important to develop protection systems against groundwater pollution. To analyze the effectiveness of such protection systems at the design stage, it is necessary to have scientifically based information on the dynamics of changes in groundwater contamination zones. Such information can be obtained using the method of mathematical modeling. The study aims to create a numerical model for calculating the non-stationary process of geomigration when using chemical protection of groundwater from pollution. Methodology. To describe the dynamics of groundwater flows, two filtration equations are considered, which allow mathematical modeling of the filtration process both for solving planned problems and for solving problems of specialized filtration. A two-dimensional geomigration equation was used to analyze changes in groundwater quality. This equation takes into account the convective transfer of impurities in the filtration flow, dispersion, and the intensity of impurity infiltration into the groundwater flow. This equation is also used to calculate the movement of the neutralizer in groundwater. The numerical integration of the filtration equation was performed using finite difference methods. An implicit splitting scheme was used to numerically integrate the geomigration equation. Findings. A fast-applicable numerical model for calculating groundwater dynamics has been built. The model is also a platform for solving another important task – the calculation of geomigration processes. A numerical model for calculating the unsteady-state geomigration process is proposed, which makes it possible to assess not only the process of formation of contamination zones in the groundwater flow, but also to determine the effectiveness of the method of neutralizing the impurities in the groundwater flow. Originality. Effective numerical models for rapid assessment of changes in groundwater dynamics and quality under the influence of anthropogenic sources have been developed. These models take into account a set of important physical factors that affect the process of geomigration and the process of neutralizing the impurity in the groundwater flow. Practical value. A computer program has been developed that allows determining the effectiveness of the process of neutralizing an aggressive impurity in groundwater by a computational experiment to protect it from anthropogenic pollution.

Digital Visualization of Environmental Risk Indicators in the Territory of the Urban Industrial Zone

This study focused on predicting the spatial distribution of environmental risk indicators using mathematical modeling methods including machine learning. The northern industrial zone of Pavlodar City in Kazakhstan was used as a model territory for the case. Nine models based on the methods kNN, gradient boosting, artificial neural networks, Kriging, and multilevel b-spline interpolation were employed to analyze pollution data and assess their effectiveness in predicting pollution levels. Each model tackled the problem as a regression task, aiming to estimate the pollution load index (PLI) values for specific locations. It was revealed that the maximum PLI values were mainly located to the southwest of the TPPs over some distance from their territories according to the average wind rose for Pavlodar City. Another area of high PLI was located in the northern part of the studied region, near the Hg-accumulating ponds. The high PLI level is generally attributed to the high concentration of Hg. Each studied method of interpolation can be used for spatial distribution analysis; however, a comparison with the scientific literature revealed that Kriging and MLBS interpolation can be used without extra calculations to produce non-linear, empirically consistent, and smooth maps.

Mathematical modeling methods in assessing the prospects of export development in the Republic of Tatarstan of the Russian Federation

In the conditions of instability of the Russian economy, Russian regions have faced the problem of finding new directions of foreign economic development. Mathematical modeling methods, considering the distance between partner regions and their economies volumes, can be effective tools for solving the problem. The article touches upon the modeling foreign trade relations issues in the Republic of Tatarstan on the gravity models’ basis. The purpose of the study is to identify potential trade partners and assess the prospects for the export relations development in the Republic of Tatarstan. The structure, dynamics, and main directions of exports of the constituent entity have been analyzed. Potential trade partners of the Republic of Tatarstan among the Commonwealth of Independent States countries have been identified using the classical gravity model based on assessing the internal regional product and the distance among the regions. The prospects of foreign trade relations with Belarus and the Republic of Uzbekistan have been assessed. Based on J. Tinbergen’s gravity model models of interaction among the regions have been built and forecast values of export volumes for the short term calculated. It was revealed that the Republic of Azerbaijan can become a potential partner for the Republic of Tatarstan. The analysis of the forecast data on the domestic regional product of the Republic of Tatarstan and the gross domestic product of Azerbaijan in 2023 suggests that the exports volume between these entities is expectedly high.

ОБОСНОВАНИЕ КОНСТРУКЦИИ КРЫТОГО ГРУЗОВОГО ВАГОНА С УВЕЛИЧЕННЫМ ОБЪЕМОМ ГРУЗОВОГО ПОМЕЩЕНИЯ

The market of covered freight cars, as well as existing designs of this car type of domestic and foreign production is analyzed. Promising trends of making innovative designs of freight cars for the transportation of piece and container goods are found out. The original design of a covered freight car with an increased body space due to the use of the space between trucks is proposed. To reduce the complexity of loading and unloading operations, sliding sections of the side walls and roof are provided in the car design. To confirm the compliance of the proposed design with the requirements of regulatory and technical documents, the car was entered into the dimension, checking for automatic coupling at the junction of a straight line and a curve, passage in the coupling of an s-shaped curve and coupling of a straight line and a curve, and a single car along a circular curve of a small radius, as well as passing without self-decoupling of the hump of the sorting slide, the ramp exit of the train ferry. A safety assessment is carried out with regard to rolling the wheel onto the rail and overturning the car in curves. The car dynamic characteristics are found out by mathematical modeling methods. The assessment of the strength of the body load-bearing structure, lifting mechanisms of the floor sections, sliding sections of the roof and side walls is performed using the finite element method implemented in the environment of a specialized software package. The results obtained as a result of calculations and computer modeling confirmed the operability and safety of the proposed design of a covered freight car with an increased loading space.

COMPARATIVE ANALYSIS OF SPECTRAL ANOMALIES DETECTION METHODS ON IMAGES FROM ON-BOARD REMOTE SENSING SYSTEMS

The subject matter of the article is methods of detecting spectral anomalies on images from remote sensing systems. The goal is to conduct a comparative analysis of methods for detecting spectral anomalies on images from remote sensing systems. The tasks are: analysis of the main methods of detecting spectral anomalies on images from remote sensing systems; processing of images from remote sensing systems using basic methods of detecting spectral anomalies; comparative assessment of the quality of methods for detecting spectral anomalies on images from remote monitoring systems. The methods used are: methods of digital image processing, mathematical apparatus of matrix theory, methods of mathematical modeling, methods of optimization theory, analytical and empirical methods of image comparison. The following results are obtained. The main methods of detecting spectral anomalies on images from remote sensing systems were analyzed. Processing of images from remote sensing systems using the basic methods of detecting spectral anomalies was carried out. A comparative assessment of the quality of methods for detecting spectral anomalies on images from remote monitoring systems was carried out. Conclusions. The spectral difference of the considered methods is revealed by the value of information indicators - Euclidean distance, Mahalanobis distance, brightness contrast, and Kullback-Leibler information divergence. Mathematical modeling of the considered methods of detecting spectral anomalies of images with a relatively “simple” and complicated background was carried out. It was established that when searching for a spectral anomaly on an image with a complicated background, the method based on the Kullback-Leibler divergence can be more effective than the other considered methods, but is not optimal. When determining several areas of the image with high divergence indicators, they should be additionally investigated using the specified methods in order to more accurately determine the position of the spectral anomaly.