Статьи журнала - Вестник Южно-Уральского государственного университета. Серия: Компьютерные технологии, управление, радиоэлектроника
Все статьи: 1048
Статья научная
We consider the problem of phased implementation of automated information-measuring systems at thermal power plants, economic efficiency of which is determined by their reliability, cost, volume, automated, errors of measurement, number of measuring channels, level of qualification and number of staff, as well as the impact on the performance of automated control systems and power equipment. The article formulates principles for decision-making in the application of automated information-measuring systems for thermal power plants based on the analysis of experience. In the first part of the review describes the experience of using workstations for electricity metering and registering of vibration condition of equipment and emergency situations. There are recommendations for the transition to the next stage of automation. In the second part of the review describes the experience of implementing a second stage of automation to account for the power and energy, technical diagnostics of turbine equipment and registration of emergency events. In the third part of the review we consider the problem of searching for invalid the loss of energy and technical diagnostics of measuring channels of automated information-measuring systems, as well as recommendations for the conduct of personnel policy. The recommendation is focused mainly on thermal power plants not equipped with full-scale automated control systems of technological processes.
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The scheduled maintenance allows us to prevent breakdowns and unplanned downtime of equipment but limits the flexibility of manufacturing systems. On the other hand, condition monitoring concept enhances the manufacturing systems flexibility but requires reliable diagnostic information in real-time. Modern technologies, e.g., wireless power and Industrial Internet of Things (IIoT), allow implementing high-sensitivity sensors such as the Wireless Acceleration Sensor (WAS) for condition monitoring. The WAS is mounted on a machinery rotating shaft and the WAS measures angular, linear accelerations and angle of the shaft simultaneously. Moreover, the WAS contains a high-performance microcontroller, which allows processing measured data and estimating machinery condition in real-time. However, the accuracy of the angle measurement by the WAS significantly affects the accuracy of linear accelerations measurement by the WAS. In this paper, the authors propose the novel numerical method which allows us to measure accurately of a rotation angle and linear accelerations of the shaft. The method is based on a regularization technique and application of finite-difference equations. Besides, the study shows the results of simulation at applying the numerical method to calculate the rotation angle of the shaft using measurement data, which contain noise, obtained from the wireless accelerations sensor. The simulation results show that the numerical method effectively determines the rotating angle and the method is robust to noise.
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Developing the corporate standards on planning projects in real estate and construction sector
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Project management is an important stimulus for development of different countries and regions, industries, as well as organizations - companies and firms. Projects realization aiming to help organizations in achieving its strategic goals have to have the certain management system, including all processes from initiation till completion with the key role of planning. The challenge that companies faces today is to develop the adequate and optimum corporate standard at the company level when the project management standards and the sector (industry) normative documentation have different glossaries and terminology. Companies task is to develop the norms and rules at its level that will give the possibility to organize the project planning processes combining the existing PM methodologies approaches and specific sector normative documentation. In modern world it is important to develop and apply planning processes to provide the companies with the tools to achieve the goals and objectives in more efficient way both at the organization and separate projects levels as social and economic systems. The authors of the article analyze planning processes in the existing project management international and national standards, define the problem and set the task of developing the project planning standard for application in the certain sector of economy or industry.
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This paper describes creation of database application, which correspond the requirements of data security. The main emphasis is put on protection of personal information. It is shown that increase of security level is reached due to normalization, especially to the level of the fifth normal form, safety of metadata and tables keys, existence audit tool for control user actions, the accounting of the destroyed data and its repeated destruction at restore database from backup copy, determination of volume of the destroyed data, which won't allow inappropriate data using.
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Статья научная
There are three main problems of interaction people with limited mobility with social infrastructure facilities (SIF): the first is physical, the second is the inaccessibility of information about the SIF, and the third is social. The accessibility of SIF and information about it can be ensured through use electronic maps of urban areas and SIF (digital city). These circumstances determine the relevance of the development and creation of a geoinformation support system for decision support in the field of social infrastructure accessibility for people with limited mobility. An original approach to the development and creation of technology to meet the needs for obtaining formalized spatial data, as a social tool for geographic orientation, an information and reference system for supporting decision-making in the field of social development is proposed. The purpose of the study is to develop a system for managing and monitoring the city’s social infrastructure facilities. Materials and methods. The conceptual model of the system was developed using GIS technologies and the theory of formal concept analysis (FCA). The online version is implemented using PHP, JavaScript. Results. The paper presents a methodology for implementing a decision support system. An Internet version of the system has been implemented. The system functionality and interface were tested with the involvement focus groups of people, interested in using the development. Conclusion. A system for managing and monitoring city’s social infrastructure facilities has been developed and implemented. The work is useful in the field of municipal management of social infrastructure, as well as for people with disabilities and researchers.
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Development of a management and monitoring system for a city farm
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For any manager of an agro-industrial enterprise, the use of resources is used for the efficient use of resources: labor, land, working capital and other. For this reason, the production processes of agriculture are already almost completely mechanized around the world, which is the productivity of an enterprise. The next logical step in increasing the productivity of agricultural enterprises is the automation and digitalization of agricultural production. Therefore, in order to remain competitive with the world leaders in agricultural production, it is necessary to integrate IoT technologies. It is predicted that the introduction of modern automation technologies in the agro-industrial complex will increase yields more than the inventions of the tractor, herbicides and GMOs. City farming is gradually becoming such a solution. In some megacities, urban farms are built on the rooftops of buildings, and in some places there are entire skyscrapers with vertical farms. Experts say that the quality and environmental friendliness of products grown in this way is much higher than that of counterparts grown in a traditional way. In this regard, the relevance in creating an application for a smart farm has been identified. Such an application will allow you to be more attentive to all parameters of plant growth thanks to sensors for humidity, light, temperature and other data that can be transmitted to a smartphone. The purpose of the study is to develop a management and monitoring system for a city farm. Materials and methods. The mobile application is implemented using the Xamarin framework in C# and JavaScript. The firmware for the microcontroller is written in C. Results. The paper provides an overview of management and monitoring systems for smart farms, a methodological comparison of advantages and disadvantages. The architecture of the control and monitoring system was also discovered. Implemented a mobile application and software. The functionality and design of the mobile application has been tested on various devices. Conclusion. The city farm management and monitoring system has been successfully developed. As further scientific work, it is planned to develop a mathematical model for more optimal farm management. This work can be useful in the field of decentralized agriculture.
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Development of a mining simulation model for potassium ore mining planning
Статья научная
Introduction. In this article, we show the importance of potash fertilizers produced by PJSC Uralkali, Berezniki, Perm Territory for agriculture and the economy in general. А process of potassium ore underground mining is described from breaking up moment till transportation to the surface. An importance of production planning for the mining enterprise functioning is substantiated. Various levels of planning, from a general production plan to a weekly and daily plans are described. The problem of such planning at PJSC Uralkali is in using only integral performance indicators, it leads to significant errors. It is proposed to use simulation modeling as a possible solution to the problem. Purpose of work. The purpose of this work is to develop a simulation model of mining operations, from the process of breaking and transporting ore to a conveyor-transport system, and to test model's applicability for ore mining planning. Since the existing software has a number of limitations in applies to potash mines, a specialized object-oriented library allows modeling queuing systems, multi-agent and active systems is used as a basis for modeling. The limitations and assumptions of the model are described. Materials and methods. The model is igned as a deterministic automaton. The end point for ore mining process modeling is the transfer of ore to the unloading point, because further transportation of ore is not a limiting factor for mining. Conclusion. The special states of all objects of the system including mining combine - self-propelled car - unloading point and all possible transitions between them are described. A data from open sources is taken to check the adequacy of the model. Changes in the simulation results are investigated for various input parameters in the developed software. The simulation results are of a pulsating character due to the periodic execution of the harvester drive away. A productivity of the combine decreases with an increase in the distance traveled by a self-propelled car. The possibility of transition to a stochastic model is investigated. An expected decrease due to an increase in the downtime of the combine is shown. A conclusion about the applicability of the model to improve the quality of planning for underground potassium ore mining is made based on obtained data.
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Development of a multilayered hybrid power divider
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The paper proves a real possibility of designing the microwave electronic devices based on multilayer structures. The advantages of such design compared with a traditional application of the microstrip lines are demonstrated by an example of a hybrid microwave power divider (hybrid ring). The calculations of a multistructure-based hybrid ring presented in the paper allow forecasting a substantial decrease of the weight and size parameters for the microwave electronic devices. That provides their wide application in mobile and small-sized radio systems with a microwave informational channel. The weight and size problem is especially relevant for the devices like the various mobile on-board radars. This makes it possible to predict scientific and industrial relevance of the development.
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Статья научная
Time series analysis became one of the most investigated fields of knowledge during spreading of the COVID-19 around the world. The problem of modeling and forecasting infection cases of COVID-19, deaths, recoveries and other parameters is still urgent. Purpose of the study. Our article is devoted to investigation of classical statistical and neural network models that can be used for forecasting COVID-19 cases. Materials and methods. We discuss neural network model NNAR, compare it with linear and nonlinear models (BATS, TBATS, Holt's linear trend, ARIMA, classical epidemiological SIR model). In our article we discuss the Epemedic.Network algorithm using the R programming language. This algorithm takes the time series as input data and chooses the best model from SIR, statistical models and neural network model. The model selection criterion is the MAPE error. We consider the implementation of our algorithm for analysis of time series for COVID -19 spreading in Chelyabinsk region, and predicting the possible peak of the third wave using three possible scenarios. We mention that the considered algorithm can work for any time series, not only for epidemiological ones. Results. The developed algorithm helped to identify the pattern of COVID -19 infection for Chelyabinsk region using the models realized as parts of the considered algorithm. It should be noted that the considered models make it possible to form short-term forecasts with sufficient accuracy. We show that the increase in the number of neurons led to increasing accuracy, as there are other cases where the error is reduced in case of reducing the number of neurons, and this depends on COVID -19 infection spreading pattern. Conclusion. Hence, to get a very accurate forecast, we recommend re-running the algorithm weekly. For medium-range forecasting, only the NNAR model can be used from among those considered but it also allows to get good forecasts only with horizon 1-2 weeks.
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Development of automatic control system of hot-strip mill process parameters
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It is observed that the contemporary trend of rolling development is widening of hot-strip mills assortment because of ultrathin hot-rolled strips production instead of cold-rolled ones. The advisability of the automatic control system of process parameters (such as tension, gauge, and roll speed) update is demonstrated on the examples of wide-strip mills 2000 and 2500 at Magnitogorsk Iron & Steel Works. Control algorithms for electric drives speed rates are examined, which provide proportional position control of finishing rolling speed under control and perturbation actions with corrective action transmission against rolling direction. Corrected digital algorithms of tension dynamic control enabling longitudinal grow-back decreasing due to accuracy increase of looper electric drive torque and loop size in interstand space computation are presented. The streamlined structure of automatic control system of strip gage (ACSG). The system realizes control method on base of indirect control with sensor values averaging over a specified period of time combined with direct control following exit gage signal and external correction providing perturbation actions compensation and draft redistribution in finishing trains. The developed system of automatic head end gage correction by moving rollers apart before strip enters mill with their subsequent return to specified position for main strip end rolling is demonstrated. The results of improved ACSG application investigations on operating rolling mill are presented. The method and the system of interactive tension and strip gage control are proved and examined whereby automatic correction of hydraulic roll screwdown position of the previous stand under perturbation and control actions caused by change of looper or roll screwdown of the next stand positions is implemented. The results of research and commercialization of the developed systems confirm technical-and-economic efficiency provided with reduction in input of materials, improvement in the quality of production and steadiness of the processing.
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Development of methodical maintenance of decision support process automated control production
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The article suggests a complex system models of industrial enterprises, which connect with the object management. These models allow us to construct a single circuit management of expenses on the responsibility centers with decomposition on hierarchical levels. The article presents valuation model optimal point in time for the formation of control actions based on Kolmogorov differential equations. This mathematical model allows us to implement the principle of coordinating actions to manage costs in the abnormal production situations. This model allows you to define the consequences functions of taken decisions using functional and cost analysis. The article describes technique of creation of decision-making support procedures in emergency production situations on the expenses model system. This model formalizes knowledge of domain data experts. The model need to automate functions of intellectual control.
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Development of the identification system by fingerprints
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Dactyloscopy (fingerprint recognition) is the most developed to the date biometric method of personal identification. The catalyst for the development of the method was its widespread use in criminology of the XX century. As each person has a unique papillary pattern of fingerprints, so identification is possible. Typically, algorithms use characteristic points on fingerprints: the end of the pattern line, branching lines, single points. In addition, information about the morphological structure of the fingerprint is attracted: the relative position of the closed lines of the papillary pattern, “arched” and spiral lines. Peculiarities of papillary patterns are converted to some unique codes, which preserves the information content of the fingerprint image. And it is “fingerprint codes” that are stored in the database used for searching and comparing. Currently, fingerprint recognition systems occupy more than half of the biometric market. A lot of companies are engaged in the production of access control systems based on the method of fingerprinting identification. Due to the fact that this direction is one of the oldest, it has become the most widespread and is currently the most developed. Fingerprint scanners have come a really long way to improve. Modern systems are equipped with various sensors (temperature, pressing force, etc.), which increase the degree of protection against counterfeiting. Every day the systems become more convenient and compact.
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Diagnostic model of management risk analysis
Статья научная
Much attention in scientific and scientific-practical publications is given to the problem of risk management. However, the issues of theory and practice of constructing the company's risk management systems and policies remain insufficiently developed. Solving the problems of comparative assessment of the level of risks when choosing an investment policy for the implementation of the chosen strategy of the company's development is topical while ensuring the sustainability of the strategic development process. Assessment of management style and level of managerial risks is carried out on the basis of the economic-mathematical model of quantitative evaluation of qualitative parameters. The analysis is carried out by comparing the actual level of its investment activity with a reference value that takes into account the company's life-cycle phase (LCS). The commonly accepted classification of LCS stages and the method of quantitative evaluation of the integrated indicator of the company's investment activity are used in the work. A diagnostic model for analyzing the level of managerial risks in the implementation of the investment policy of the company's development strategy is proposed. The developed mathematical tool allows to diagnose the level of managerial risks, management style, and also the type of investment policy implemented by the company depending on the LCS stage of the company.
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Introduction. The method of processing experimental data obtained in the form of a time-varying non-stationary signal is described. In the experimental study of transients associated with changes in the heart rate of schoolchildren during a proof-reading test, it became necessary to develop a new effective method for processing the results of dynamic measurements. Purpose of the study. Consider the main points of this methodology, which is based on the Prony method, and the possibility of its use in the field of studies of changes in heart rate variability (HRV) in response to various functional test influences. Materials and methods. Traditional approaches related to the calculation of power spectral density (PSD) and based on classical spectral methods are currently very widespread. The model of constant rhythm is not applicable for non-stationary dependencies of HRV. For spectral analysis of time dependences of HRV reflecting transient processes (non-stationary processes) it is proposed to apply spectral analysis on the plane of complex frequencies (PCF). PCF is a generalization of the usual spectrum. The calculation of the PCF is based on the Prony procedure, based on parametric modeling. Results. PCF reflects the frequency structure of oscillations of unsteady physiological signals, therefore, can be used to classify them. It is shown that the use of spectral analysis on the plane of complex frequencies for transient processes of the heart rhythm makes it possible (according to the parameters of the PCF) to calculate, for diagnostic purposes, the numerical values of the parameters characterizing the reactions of various regulatory mechanisms of the heart rhythm in response to various functional test influences. Conclusion. The best results, as compared with the methods of classical spectral analysis, for the analysis of transients in the form of a HRV signal were given by approaches based on the use of spectral analysis on the plane of complex frequencies.
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Management of the market economy requires the use of various economic and mathematical methods and models. The modeling method is the most important universal method of investigation. The model, as a rule, differs from the object of research, but certainly has a similarity, similar to this object, primarily with respect to those characteristics that are subject to study and forecasting. The model of a complex system is also a system that has a physical embodiment, or written with mathematical notation, numbers, words, graphic images, and so on. Thus, the model is a physical or sign system similar to the system under investigation with respect to the functional and structural characteristics that are the subject of the study. There are various economic and mathematical models that are used in scientific research. The most common are the models of correlation-regression analysis, production functions and systems of econometric equations. As a rule, modern research in the field of economics and management is focused on the use of a single tool for data analysis. This article will consistently apply all of these models, which allows you to conduct the most complete and objective analysis of the mutual impact of production performance of a construction company. The article proposes an economic and mathematical model of competitiveness management of a construction enterprise based on the compilation of a system of recursive econometric equations. Formulas for calculating the endogenous and exogenous variables participating in the model are given. The calculation of the main performance indicators of the construction company is made. Proceeding from the constructed model and based on the methodology of multicriteria optimization, the authors determined the optimal indices of the production activity of the construction enterprise taking into account the given limitations. The authors analyze in detail the obtained results of calculations and convincingly proves the relevance of the methodology proposed in the article.
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Federated learning is utilized for automated ground robot navigation, enabling decentralized training and continuous model adaptation. Strategies include hardware selection, ML model design, and hyperparameter fine-tuning. Real-world application involves optimizing communication protocols and evaluating performance with diverse network conditions. Federated learning shows promise for machine learning-based life learning systems in ground robot navigation. Research objective: to explore the use of federated learning in automated ground robot navigation and optimize the system for improved performance in dynamic environments.
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Energy saving with the help of information and measuring systems: security system modeling
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Introduction. In conditions of uncertainty and risk, the task of saving energy production or consumption costs in the aspect of safety is relevant. An effective tool for solving the problem is the use of information and measurement systems. Aim. Building safety models for energy saving using information and measurement systems based on a systematic approach. Materials and methods. Traditional approaches to solving problems using information and measurement systems do not take into account the systematic approach to risk accounting. New models and method based on a systematic approach to risk accounting are proposed. The model of the security system includes a set of necessary energy-saving measures. The model for assessing the effectiveness of a security system for energy-saving measures takes into account the interests of all information and measurement systems participating in the implementation process. The method for creating a security system takes into account the interconnections of energy-saving measures. Results. The developed models and the plan for creating a security system make it possible to minimize economic, informational, psychological, environmental and didactic risks when implementing energy-saving measures using information and measurement systems. Conclusion. The implementation of the developed models and the plan for creating a security system at the Chelyabinsk thermal power station-2 ensured a reduction in risks when performing energy-saving measures using an automated system of integrated energy metering.
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Статья научная
Introduction. The basic theoretical information on measuring systems in radar is presented, an analysis is performed to determine the errors of direction finders, and calculation expressions are found to determine the magnitude of the direction-finding errors by a single-pulse method in the Fresnel zone of a linear receiver antenna array caused by the combined action of the internal noise of the radio direction finder receiver and the angular noise of extended reflective interference. Purpose of the study. To consider the influence on the magnitude of the errors of direction finding together of the levels of the side lobes of both the differential and total directivity characteristics of the receiving antenna of the radio direction finder in the Fresnel zone. Materials and methods. Approaches for determining the magnitude of direction-finding errors are a generalization to the Fresnel zone of the known result of calculating the error during operation of a monopulse direction finder in the far zone of the receiving antenna. Results. The influence of the angular size and the distance size of a multi-point reflector on the magnitude of direction-finding errors by a single-pulse method in the Fresnel zone of a receiving linear antenna array of a radio angular system is investigated. Conclusion. Theoretical methods of measurement in radar are considered and it is shown that expanding the functionality to ensure high accuracy of measuring an information parameter will improve the accuracy of determining errors in direction finding systems.
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Статья научная
Approaches to the enterprise control under conditions of certainty and uncertainty are considered. Economic and mathematical model of manufacturing and sales enterprise is constructed in the form of nonlinear difference equations, determining the correlation of material, information and financial flows within the enterprise. This allows solving the problems of analysis and control of economic processes both in the enterprise in general and in its subdivisions. The solution to one of the possible problems of enterprise adaptation to changeable market conditions is considered, and the method of estimate of adaptation efficiency is introduced. The problems of enterprise parameter optimization and optimal control of the enterprise behavior under conditions of incomplete information and market environment changes are stated and solved. The algorithm of estimation of state vector of the system is obtained for the conditions of incomplete information. The results of modeling are given. The economic and mathematical model and the algorithms of estimation and control can be applied in the design of the enterprise automated control systems software.
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Estimation of mutual coupling in finite array of dipoles
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Mathematical modeling of the mutual coupling in finite phased array of dipoles with complex shape reflector is developed. The complete set of equations of the mathematical model is formulated as Pocklington integral equation for dipoles current distributions and integral equation of II kind for the scattering field of reflector. Offered compact form of the mathematical model as the set of the functional matrix equations includes special iterative procedure for obtaining the required accuracy and stability of the numerical solution.
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