Operation Of Technical Systems Research Articles

Обоснование информационно-интеллектуальной поддержки принципов действия технических систем

Information and intelligent systems are a combination of knowledge, methods and technologies aimed at supporting specialists and engineers in the design, operation and optimization of technical systems. The task of searching for acceptable principles of operation of technical systems is achieved by searching for optimal solutions, analyzing their characteristics and identifying the most preferable options from the point of view of the assigned tasks. When searching for optimal solutions, various options for operating principles should be considered. A rational choice of the fundamental principles of the functioning of a technical system ensures the efficiency and quality of management decisions made. The purpose of this work is to substantiate the information-intellectual system of multivariate analysis, which provides the search for technical solutions. A logging road is considered as the object of study. The features of the organization of work during the construction of logging roads have been studied, and the choice of research method has been justified. An information-intellectual system is described that generates for further development acceptable principles of action in technical solutions in accordance with the formulated task. A description of the information-intelligent system for searching technical solutions is presented. The set of solutions is described in the form of an AND/OR tree, which allows you to efficiently store and select feasible solutions using graph methods.

Mechanization, Automation, Robotization and Digitalization: Conceptual Clarification and Systematization

The paper highlights the importance of clarifying scientific terminology to delineate the exclusion of humans from technical systems, in particular the concepts such as «mechanization,» «automation,» «robotization,» and «digitalization» that are commonly used in scientific literature without a precise definition of their essence and distinctions. (Research purpose) The paper aims to provide clarity and systematic categorization of terms employed to describe the exclusion of humans from agricultural technical systems. (Materials and methods) The paper employs the Theory of Inventive Problem Solving (TRIZ), the Theory of Decision Making, and the System Method as theoretical frameworks. (Results and discussion) The paper provides a comprehensive clarification of the conceptual meanings attributed to terms such as mechanization, automation, robotization, and digitalization. It outlines their classical (Aristotelian) definitions and systematically categorizes a broad spectrum of related concepts, including mechanization, automation, robotization, intellectualization, digitalization, cyber-physical system, precision agriculture, digital agriculture, and smart (intelligent) agriculture. The obtained results are compared utilizing the approach of the Food and Agriculture Organization of the United Nations (FAO). (Conclusions) It is concluded that the concept of mechanization, in contrast to the FAO approach, does not encompass farming reliant on manual labor and animal traction. It is determined that robotization necessitates intellectualization, whereas automation does not necessarily require it. Furthermore, digitalization is demonstrated as a means of implementing automation, robotization, intellectualization, and optimizing the operation of technical systems.

Формализация автоматизации определения амплитудно-частотных характеристик элементов зданий

The amplitude-frequency characteristics of vibrations of structural elements of buildings and structures are important design parameters when analyzing changes in the stress-strain state of a building during operation, including during surveys and monitoring of the technical condition of the building. Standardization of the method for determining the values of these parameters is carried out in accordance with the requirements of GOST 8.009 to ensure compliance with the requirements of GOST 31937 and GOST 32019. The vibrations of a building are a superposition of their own and forced vibrations caused by various internal (operation of household appliances and various technical systems of the building) and external (urban transport, construction sites, etc.) influences. To determine the values of the period, as a rule, the building's own vibrations are recorded, caused by the natural dynamic natural and man-made background of the city (if there is equipment sensitive to the levels of natural dynamic impact), therefore, no additional effects are exerted on the building during the measurement process. Industrial buildings are characterized by the presence and movement of heavy technological equipment inside buildings. Stresses during fluctuations have an alternating character, therefore they can cause fatigue of the material from which the structure is made. This, in turn, leads to the destruction of individual elements of the structure and, as a result, to accidents. The paper presents a dynamic calculation of the elements of the structure consisting of several stages: the dynamic characteristics of the nodes of the joints of the constructs with each other are determined; the dynamic degrees of freedom are determined; the theoretical calculation for vibrations is formalized.

A comparative analysis of the methods of evaluating dependability using Big Data of complex system operation

Aim. The paper aims to research the methods of evaluating dependability indicators based on the analysis of Big Data obtained in the course of monitoring the operation of technical systems and their components. A comparative analysis is performed of the efficiency of robust statistical methods of evaluating the dependability indicators of complex technical systems based on operation data.Methods. The paper uses methods of mathematical statistics, specifically robust methods of evaluating the translation parameter of a noisy sample and numerical methods of statistical modeling. The authors consider five methods of evaluating the translation parameter: sample mean as a nonrobust method used for comparison; sample median as the simplest robust method of evaluating the translation parameter; two-stage evaluation procedure with truncation of outliers according to the three sigma rule; two-stage evaluation procedure with truncation of outliers using Tukey’s box-and-whisker plot; Huber’s robust method. The comparative analysis of the methods of evaluating system dependability indicators was conducted by means of statistical modeling in the R statistical computation package. Five distribution laws for generating an element’s time-to-failure and recovery time samples were considered: exponential distribution, Weibull distribution, log-normal distribution, gamma distribution and uniform distribution.Results. Statistical analysis of Big Data associated with the operation of technical systems is complicated by the heterogeneity and noisiness of such data, as well as the presence of errors and outliers of varied nature. That is primarily due to the varied loads and operating conditions of each object. Herein this problem is examined as regards the problem of evaluating the dependability indicators of a structurally complex monotonic system with independent element recovery. The paper examines methods of rejecting anomalous data and robust evaluation of the sample position parameter and performs a comparative analysis of the efficiency of such methods for various distribution laws. It is shown that robust methods of evaluation enable significantly higher accuracy as compared to the standard sample mean. The two-stage procedure based on the truncation of outliers and Tukey’s box-and-whisker plot proved to be the most efficient.Conclusions. The paper’s findings allow improving the accuracy of evaluation of dependability indicators based on complex technical system operation data. They can be used in Big Data processing and complex system dependability theory.

Модель функционирования технической системы с учетом организации регламентных работ

Рассмотрены два подхода к организации функционирования и обслуживания технической системы, отличающихся порядком использования запасных типовых элементов замены. Показано, что задача определения необходимого их количества для локальной вычислительной сети не может быть сведена к решению классических задач теории управления запасами. Разработаны математические модели функционирования и технического обслуживания системы, позволяющие определить необходимое количество запасных типовых элементов замены. The article revises two operation and maintenance organization approaches that have different spare elements use order. It is showed that the task of defining the required spare element quantity for local network cannot be derived from classic theory of stock management. The article describes developed math models for operation and maintenance that allow to define the required spare elements quantity.

Разработка конструкции индуктора для закалки детали сложной формы

Due to active process of import substitution, domestic industry starts producing the parts previously purchased abroad. These parts are necessary for stable and reliable operation of various technical objects and systems. Thus, the development of a technological installation for hardening a metal profile is topical. The task is complicated by the fact that the profile has very thin irregularly shaped walls, which should be hardened only from the inside, while the outer wall of the profile should be heated minimally to maintain strength. The studies have been carried out on simulation models of electromagnetic and thermal fields, which make it possible to reproduce the process of induction heating of the research object. Since the part has the same shape along the entire length, the simulation of the process of its induction heating is performed in two-dimensional space. The authors have developed a simulation model of the process of induction heating of a part of a non-standard shape, which includes calculations of thermal and electromagnetic fields. The design of the inductor is proposed, supplemented with ferrite inserts, which makes it possible to achieve the temperature regime necessary for the hardening process. The developed simulation model makes it possible to evaluate the distribution of the thermal and electromagnetic fields of the part, thereby predicting getting the temperatures required for its hardening when using various designs of inductors. The results of numerical experiments are consistent with the physical concepts of induction heating and prove the possibility to use induction hardening for thin-walled parts of complex shape instead of laser hardening used for this type of parts. The proposed model can be used in engineering practice to design inductors of non-standard parts.

Оценка уровня критичности операционного риска банка на основе нейросетевых технологий

The article is devoted to the issues of controlling the operational risks of a credit institution arising in the process of using IT technologies. Among banking risks, operational risk occupies a special place, primarily due to the fact, that it affects various areas of banking activity and is difficult to separate from other types of risk. Operational risks arise, among other things, as a result of downtime or incorrect operation of technical systems and equipment. Due to the constant growth in the degree of automation of banking business processes, new IT risk groups are emerging that can have a significant impact on the activities of a credit institution. The aim of the work is to create an artificial neural network using the high-level Keras library in Python, which automatically controls the level of criticality of the IT risk that has arisen. In the article, based on the analysis of risk events associated with the use of IT technologies, the data flows entering the input of the neural network is identified and its structure is determined. The paper also presents the results of training a neural network created by the authors based on the generated data sets. The use of intelligent methods for assessing the level of criticality of operational IT risk allows you to quickly take measures to minimize the consequences, and thus reduce direct and indirect losses. In connection with the above, the automation of operational risk management based on the use of neural network technologies is currently one of the most urgent tasks for credit institutions. The results obtained are new and can be used by credit institutions in the process of building automated systems for monitoring and managing operational risks.

Professiographic study of the professional activities of operators anti-aircraft missile systems

The rapid improvement of weapons and military equipment of anti-aircraft missile forces, the complication of the tasks assigned to the calculations of modern anti-aircraft missile systems and the conditions for their implementation, necessitates taking into account the human factor and revising the requirements for operational personnel, due to the increased impact of the psychological component of their professional activities. This article actualizes the problem of psychological support for the reliability of the professional activities of operators of anti-aircraft missile systems. The main stages of a professional study of the professional activities of operators of anti-aircraft missile systems, carried out in order to improve the methods of their selection and professional training, are described. An expanded list of professionally important qualities formed as a result of the study, which the operator of an anti-aircraft missile system must have for successful activity, as well as a list of integral professionally important qualities, is presented. The results of the study can be used in the selection of methods for identifying and determining the level of development of integral professionally important qualities of operators of complex technical systems for military purposes at the stages of selection and training.

Simulation models based on Petri nets for the analysis of maintenance and repair processes of complex technical systems

The presented review analyzes the approaches and methods of using simulation models in the maintenance and repair organization of the complex technical objects and systems. The development of the concept of "Industry 4.0" and the Internet of things involves the transition from periodic and preventive maintenance to predictive maintenance based on the study of processes during the object operation. It is shown that system models based on Petri nets are convenient for describing and analyzing technological processes and equipment maintenance. The effectiveness of timed stochastic colored Petri nets for virtual tests in the design of maintenance and repair procedures in complex systems is revealed. The use of hierarchical Petri nets allows building complex models that describe interrelated processes. A general model based on a hierarchical network is proposed to study the processes of deterioration and degradation of the technical object aggregates and elements and to form a predictive maintenance strategy. The model includes a Gantt chart of production tasks, a set of active and reserve units, maintenance and repair modules. The examples of simulation models on Petri nets for various technical systems are considered. Solutions for flexible production systems, railway bridges, offshore wind turbines, an aircraft fleet, a group of robotic vehicles, and a complex of computer equipment of an enterprise are given. The models of various maintenance strategies are considered and the generality of the models based on hierarchical Petri nets is shown. The article formulates methodological principles for constructing hierarchical networks to simulate the operation and maintenance of technical systems. The article analyzes known software tools for the implementation of timed stochastic colored Petri nets. The summary concludes that the use of simulation models on Petri nets is promising for organizing maintenance and repair of complex technical objects and systems.

Review of Energy Consumption by the Fish Farming and Processing Industry in Croatia and the Potential for Zero-Emissions Aquaculture

Higher energy efficiency and lower environmental impact have become very important aspects in the evaluation of the design and operation of technical systems. The same goes for the fish farming sector, which continuously aims to reduce its environmental footprint as well as its operating costs. This paper reviews the energy needs of the fish farming sector and their impact on the environment, and discusses the possibilities of improving the environmental friendliness of this sector by employing a higher share of renewable energy sources. The fish farming process is divided into its constitutive phases: fish breeding with associated activities, transportation, and handling of grown fish, together with relevant processes; and final processing and distribution to the customers. For these phases, the energy consumption and associated emissions, depending on the energy source, have been assessed. The parts of the process with the highest potential for the integration of alternative powering options and consequent environmental improvements are identified. The case study deals with the fish farming process in Croatia, for which a set of alternative powering options has been proposed, considering the existing energy supply, i.e., import of fossil fuels and current Croatian electricity mix, as well as renewable energy potential, which is reviewed in the paper.

The Use of Catastrophe Theory in Forensics

The modern theory of catastrophes contributes to the understanding of dynamic situations that govern the evolutionary development of natural phenomena, society, and man, as well as the prediction of the instability of various dynamic systems that can have catastrophic consequences. The results of the development of this theory are widely used in various fields of knowledge: in physics, biology, economics, medicine, psychology, linguistics, ecology and other sciences. The paper attempts to use the theory of catastrophes in forensic science, in particular, in the investigation of criminally relevant incidents of a man-made nature related to professional activities, which are inherently a destructive product of the functioning of various dynamic systems. First, the theoretical aspects of the theory of catastrophes are briefly outlined, the main concepts and their classifications are considered (catastrophe, man-made disaster, man-made emergency, emergencies, man-made sources of increased danger, etc.), which are important for developing a methodology for investigating man-made crimes related to professional activities. In order to improve the efficiency of the investigator’s recognition activity in establishing the cause of the crime under investigation (man-made disaster), the author proposes to use schemes (probabilistic models) obtained using the techniques for constructing the so-called fault and event trees, addressed primarily to specialists associated with the operation of technical systems and supervision behind them. According to the author, this will contribute to the effectiveness of putting forward investigative leads in a criminal case and their verification.

MATHEMATICAL MODEL OF RISK CONTROL ARISING FROM THE FUNCTIONING OF COMPLEX TECHNICAL SYSTEMS FOR CRITICAL PURPOSES IN CONDITIONS OF UNCERTAINTY OF INFORMATION ABOUT THE VALUES OF PARAMETERS AND THE PHASE STATE

Introduction. The paper presents a description of the process of constructing a mathematical model for managing risks arising from the operation of complex technical unique systems for critical purposes under conditions of uncertainty of information about the parameters and phase state. The purpose of the study is to create an individual optimal strategy for managing risk events that occur during the operation of complex technical systems, which minimizes the cost of preventive work, as well as the amount of damage that may result from the occurrence of relevant events. The objectives of the study include the construction of a mathematical model for control risks arising from the operation of complex dynamic unique technical systems for critical purposes under conditions of interval uncertainty of information about the values of parameters and the phase state, since as well as an analysis of existing approaches to creating an individual forecast of changes in the state of the considered class of systems.
 Materials and Methods. The article gives a comparative description of the effectiveness of the application of the mathematical apparatus of the theory of outliers of random processes and the method of individual forecasting in solving the problem of managing risks arising from the operation of complex unique technical systems for critical purposes under conditions of uncertainty. Based on the statistical methods of interval data, a mathematical model of risk management was created, taking into account possible errors in measuring the values of the parameters of the considered class of complex systems at all control windows during the operation period.
 Results. The scientific novelty of the implemented approach lies in the use of interval data statistics, which allow the most correct consideration of possible errors associated with measuring the values of the characteristics of the studied technical systems at all stages of the control process.
 Discussion and Conclusions. The mathematical model of risk control developed in the course of the study, arising from the operation of complex technical systems for critical purposes, makes it possible to make the optimal choice of risk management strategy when using objects of this class. Along with the above, an algorithm has been developed for predicting changes in the state of a technical system during the entire period of its operation based on the mathematical apparatus of statistics of interval data, which makes it possible to take into account in the calculations the errors that occur when measuring the values of the main parameters of the system under consideration at all stages of the control process.

ГЕРМЕТИЧНІСТЬ ТА ПОЛІКРИСТАЛІЧНІ КОНСТРУКЦІЙНІ МАТЕРІАЛИ

Ensuring the tightness of rocketry structures, assemblies, individual structures and systems for various purposes is one of the important aspects of the development, production and operation of technical systems of the present and the future. In accordance with the requirements of the time for the operation and operation of the facility that is being developed, the technologies and means of ensuring tightness are changing. Modern requirements for the tightness of objects of the rocket and space industry, especially for those that are operated in conditions of weightlessness, vacuum, radiation exposure for a long time are extremely stringent.
 As shown by the experience of operating tanks designed for storing active rocket components of fuel and, accordingly, to the same extent aggressive, the frequency of loss of functionality due to depressurization statistically has two maximums: at the beginning of operation and a year or two after the start. If the causes and physics of the first are investigated in sufficient detail, then information about the nature of the second in open sources is completely absent.

Организационно-технологическое моделирование эксплуатации инженерных систем зданий с позиций стоимостного критерия систем обслуживания с перерывами

In recent years, there has been an increased interest in the application of probabilistic methods, in particular. the theory of queuing, to the evaluation of the effectiveness of the activities of management companies in the organization of the operation of technical systems of residential buildings.
 The article considers the M|G|1 service system with the possibility of breaks in the work of repair teams for basic requirements, when, for example, repair teams work on third-party orders. The optimization problem is solved from the point of view of the cost criterion. As controlled factors, the probability of a break α and its duration are proposed. Under fairly general assumptions about the behavior of the system at breaks, it is established that the optimal value of the probability α is either zero or one. Necessary and sufficient conditions are given under which a break should be implemented, i.e. α=1. With a constant duration of breaks, the conditions are determined under which α=1, and the duration of the break is optimal.

A NEW CONCEPTUAL APPROACH TO THE ORGANIZATION OF TECHNICAL DIAGNOSTICS SERVICE AT NUCLEAR POWER PLANTS WITH VVER

The article identifies and summarizes the main problems that arise in the process of production activities of NPP technical diagnostics services. The analysis is carried out and the main directions of efficiency improvement are formulated, based on the personal experience of the author. Some features of the operation of various technical diagnostics systems are disclosed. The concept of multichannel synchronized measurements developed by the author is presented.

Algorithm for control and forecasting of the functional stability of complex information-technical systems

The characteristics of the behavior of complex technical systems that realize the property of functional stability of these systems were studied. One of the possible statements of the problems of planning the operation of complex technical systems arising within the functional-parametric direction of risk theory is considered. It is shown that on the basis of the developed algorithms of the minimax assessment of the technical condition using the idea of ellipsoidal assessment, it is possible to implement a guaranteeing strategy for managing the risks of unauthorized influences. The proposed approach allows forecasting even with a small number of parameter measurements, does not require information about the stochastic properties of measurement errors and other obstacles, and has adaptive properties. The conditions for ensuring the functional stability of the technological process are given and practical recommendations for applying these conditions for decision-making in the practical implementation of production processes are described. Ensuring the functional stability of production processes is one of the most important tasks today. Currently, many different methods have been proposed to ensure a high level of functional stability, but this problem requires constant improvement and development of new approaches. In order to improve and develop methods of organizing production processes that ensure the functional stability of technological processes thanks to the implementation of an individual strategy for the operation of technical systems, an approach to the formation of an operation management strategy that ensures the functional stability of the relevant systems is proposed. An individual strategy for planning the operation of technical systems was studied, depending on their actual state, taking into account the features of this specific system. The proposed approach is advisable to use when planning the functionally stable operation of complex technical systems of responsible purpose, the failure of which is associated with significant material losses or catastrophic consequences.

Семантическая совместимость человеческих агентов при обеспечении интероперабельности в сетецентрических системах

In the situation of transition from information and control systems to a net-centric architecture and development of net-centric system (NCS), the relevance of interoperability assurance in such systems is increasing. Interoperability have to be provided at three levels: technical, semantic and organizational in accordance with Russia's state standard no. 55062-2012. The main thesis of the concept of semantic interoperability of NCS, which are based on a multi-agent approach and a systems capabilities, operations, programs and enterprises model for Interoperability assessment, were proposed in the author's previous papers. In this concept, interaction in NCS is formalized based on various types’ agents: human agents and technical agents. In this paper, the interoperability features of the human agents’ interaction within NCS are considered. These human agents can be operators of technical systems and decision-makers.

A Multi-Model-Particle Filtering-Based Prognostic Approach to Consider Uncertainties in RUL Predictions

While increasing digitalization enables multiple advantages for a reliable operation of technical systems, a remaining challenge in the context of condition monitoring is seen in suitable consideration of uncertainties affecting the monitored system. Therefore, a suitable prognostic approach to predict the remaining useful lifetime of complex technical systems is required. To handle different kinds of uncertainties, a novel Multi-Model-Particle Filtering-based prognostic approach is developed and evaluated by the use case of rubber-metal-elements. These elements are maintained preventively due to the strong influence of uncertainties on their behavior. In this paper, two measurement quantities are compared concerning their ability to establish a prediction of the remaining useful lifetime of the monitored elements and the influence of present uncertainties. Based on three performance indices, the results are evaluated. A comparison with predictions of a classical Particle Filter underlines the superiority of the developed Multi-Model-Particle Filter. Finally, the value of the developed method for enabling condition monitoring of technical systems related to uncertainties is given exemplary by a comparison between the preventive and the predictive maintenance strategy for the use case.

Event-Tree Based Sequence Mining Using LSTM Deep-Learning Model

During the operation of modern technical systems, the use of the LSTM model for the prediction of process variable values and system states is commonly widespread. The goal of this paper is to expand the application of the LSTM-based models upon obtaining information based on prediction. In this method, by predicting transition probabilities, the output layer is interpreted as a probability model by creating a prediction tree of sequences instead of just a single sequence. By further analyzing the prediction tree, we can take risk considerations into account, extract more complex prediction, and analyze what event trees are yielded from different input sequences, that is, with a given state or input sequence, the upcoming events and the probability of their occurrence are considered. In the case of online application, by utilizing a series of input events and the probability trees, it is possible to predetermine subsequent event sequences. The applicability and performance of the approach are demonstrated via a dataset in which the occurrence of events is predetermined, and further datasets are generated with a higher-order decision tree-based model. The case studies simply and effectively validate the performance of the created tool as the structure of the generated tree, and the determined probabilities reflect the original dataset.

The mathematical model of the system-oriented measuring instrument

Modern measuring instruments (MIs) are designed to obtain complete and reliable measuring information. To perform this important function, MIs must be of appropriate quality and must be reliably assessed. Using mathematical models simulate the operation of technical systems in order to decide on the optimization of its characteristics. As a result of the analysis of the model, the specific features of the studied processes and certain quantitative regularities are established. This allows to predict the processes in the system over time and determine their quantitative characteristics.
 The article presents the results of mathematical modeling of system-oriented measuring instruments as a system and its software as a subsystem using the apparatus of general systems theory. Such models with its graphical interpretation allow obtaining the necessary and useful information about the properties of the MIs as a technical system. The performed modeling makes it possible to describe the functioning of the MIs and to obtain a certain assessment of quality indicators.