Pre-emergency Situations Research Articles

Method of Diagnostics of Operation Modes of Individual Heat Supply Units, Allowing to Detect Pre-Emergency Situations at an Early Stage

The use of machine learning methods to control heat supply systems is a pressing issue worldwide. The aim of the work is to develop methods for intellectualizing the operating modes of individual heat supply units (IHU) to improve their efficiency and reliability. To achieve this goal, the following tasks were solved: creating and debugging methods for diagnosing IH operating modes; using the cluster analysis method, in particular the K-means algorithm, to identify pre-emergency situations at an early stage; analyzing the relationship between outdoor air temperature data and the pressures of direct and return network water in IHU operating modes using Novosibirsk as an example. The most important results of the work include dividing the measured parameters into five clusters, each of which characterizes a certain IHS operating mode. This was confirmed by the "Elbow Method", which determined the optimal number, which made it possible to significantly improve the forecasting of emergency modes. Studies have shown that a sharp increase in outdoor temperature leads to an increase in the pressure of direct network water, which can cause accelerated wear of heating networks due to the peculiarities of weather-dependent automation regulation. Introducing additional parameters into the initial data, such as the service life of heating networks and weather conditions, can improve the accuracy of forecasts. The significance of the obtained results lies in the possibility of early detection of emergency and pre-emergency modes of IHU operation, which helps prevent accidents and reduce repair and maintenance costs.

Critical Situations and Prevention of Accidents in Chemico-Technological Systems (Methodological Aspects)

The aim of this work is to study the causes of accidents in chemical processes, develop a methodology for accident prevention via control, and illustrat its realization by examples using a variety of strategies. The general concept of critical situations was introduced systematically covering both emergency and pre-emergency situations. In large-scale chemical plants, examples of accidents are presented. Accident causes as a result of disturbances and control faults in technological processes are analyzed. Approaches for preventing accidents are considered. The revealing of critical situations is presented as a problem of pattern recognition, and the subtasks of the recognition are analyzed. An emergency scale based on the assessment of various states of the chemico-technological process is introduced and applied for distinguishing the different levels of accident. The real obstacles in the prevention of accidents via control are shown and analyzed. Matrices of critical situations with corresponding characteristics are given. The main tasks for the prevention and elimination of critical situations are highlighted and characterized, and our methodology for the realization of these tasks is presented. Practical examples of the prevention of accidents in the industrial ammonia synthesis processes (including approaches and strategies) are demonstrated based on the real-time control of autothermal reactors.

Система предотвращения аварийных ситуаций производственных технологических объектов на основе ситуационной математической модели

The main criterion characterizing the efficiency of the equipment of an industrial facility is its operation without failures and damages. To reduce the emergency rate, there has been proposed an emergency prevention system targeted at identifying the technological situation at the facility, predicting its further development, and also de-veloping the control actions to return the facility to normal operation. The task of identifying pre-emergency and emergency situations for technological objects is realized as a particular task of recognizing a technological situation based on a situational mathematical model of an object. The situational mathematical model of the object is implemented as a set of production rules that reflect the knowledge of experts about the identification of pre-emergency situations at the object, as well as possible trajectories for bringing the control object into normal operation. A three-level grouping of the rules of the situational mathematical model by security levels is proposed. The features of the formation of the rules of the situational mathematical model in the processing of qualitative information about the object are considered. Based on the situational mathematical model, a method for identifying pre-emergency situations is proposed, the stages of the method implementation are described. An algorithm of functioning the emergency prevention system has been developed. The interaction scheme of the proposed emergency prevention system and the process control system based on the SCADA system is determined. The use of the proposed system will improve the safety and stability of the operation of hazardous technological facilities

ПОРІВНЯННЯ АВАРІЙНИХ СИТУАЦІЙ ПРИ ПЛАВАННІ СУДЕН В ЕКСТРЕМАЛЬНИХ УМОВАХ

Sea-going vessels spend about 80% of their sailing time at the open sea and about 20% under extreme conditions in confined waters. However, the number of accidents under extreme conditions is more than 90% of their total. As a result of sea disasters, about 200 thousand people die annually in the world, of which 50 thousand - directly in the water after a shipwreck, and 50 thousand die on life-saving appliances in conditions that are not really extreme. The main factors of accidents at sea, which can develop into emergencies, are violations of safety of navigation. Statistics show that most often these violations lead to navigation accidents. In total, ship collisions, bulkheads and groundings account for at least 80% of the accidents. The main reason for these situations is “human factor ", which has not been sufficiently studied and is constantly developing. Firstly, it concerns the adequate actions of operators of complex systems being in inadequate (emergency and emergency) operation of the vehicle. In this sense, to become relevant, the research must harmonize the interaction between phenomena, processes, mechanisms and systems controlled by ship operators. Special attention is paid to increasing the safety of operation of ships using the methods of event management during pre-pilot training of ship crews in crewing companies. The analysis of emergency situations during ships’ navigation under extreme conditions plays a significant role while studying crew behavior in such situations. Based on the statistical data, a special checklist was developed that will help prepare crew members for actions in emergency situations. Also, this checklist will provide an opportunity to reduce the risk of a pre-emergency situation.

MATHEMATICAL MODELS FOR DIAGNOSTICS OF A BOLTED CONDUCTIVE JOINT UNDER CONDITIONS OF CHANGING MODE PARAMETERS

The reliability of the transmission and distribution of electricity in ports, ships and energy enterprises depends on the condition of the bolted conductive joints. Operational practice shows that 2 % of cases of emergency shutdowns of technological lines and fires on electrical equipment occur due to the weakening of bolted conductive joints. The main reasons for the bolted joint weakening are dynamic changes in operating current loads and changes in climatic parameters. It is possible to increase the reliability of bolted conductive joints using modern diagnostic methods that allow identifying the appearance of bolted joint weakening. The existing methods for diagnosing the state of bolted joints, which are based on monitoring the temperature of the bolted joint, are analysed. It has been established that the use of such methods to identify the initial moment of the joint weakening is impractical, since they react to the emergency state of the bolted joint, that is, to the critical temperature value. To identify the initial moment of the bolted joint weakening, it is proposed to simultaneously monitor the values of the load current and the parameters of the ambient air, which makes it possible to increase the reliability of detecting pre-emergency situations. To diagnose the initial moment of the bolted joint weakening, it is proposed to use the estimated Boolean functions. Arguments of Boolean variables are obtained for a stationary and continuous process of changing current and ambient temperatures, a stationary and deterministic process as well as a random and deterministic process. The minimized Boolean functions are given for the normal operation of the bolted joint, when the initial moment of weakening appears and when the emergency mode occurs.

Identification of temporal anomalies of spectrograms of vibration measurements of a turbine generator rotor using a recurrent neural network autoencoder

A method is proposed for recognizing pre-emergency conditions of rotary installations based on the use of the Hamming window and advanced Deep Learning techniques in retrospective analysis of the results of accounting for the factors of operation of a turbine generator, diagnostics and control under critical impacts. A program of experimental studies on the model of a turbine plant with simulation of faults and receiving vibration signals has been developed. An experiment based on the homostatic method of checking the signal with Hamming windows, in the frequency, time and modulation domains and common initial data, allows one to determine the most promising signal characteristics for identification. A method has been developed for monitoring the state of turbine generators in an automatic mode for timely notification of the CHPP personnel about the appearance of signs of pre-emergency situations, as well as about the nature of faults by the method of predicting the state of a pre-emergency situation using convolutional neural networks implemented in the form of a recurrent autoencoder. Clustering is applied and clusters are identified that correspond to the spectrograms of pre-emergency situations. The effectiveness of the use of the homostatic method in combination with correlation analysis is based on the decision-making model described in more detail in other works.

Research into the current state of accident rate of electric networks in agriculture using the example of Astrakhan region

The paper deals with the accident rate of power electrical equipment of transformer substations of rural electric networks is studied depending on a number of factors, i.e. voltage class, service life, organizational and technical reasons for equipment damage as well as the type of equipment elements. The analysis was carried out on the basis of data for 2019 provided in the annual report of the branch of PJSC “Rosseti South”. In addition, the paper considers the information of patent documents in the subject area “Diagnostics of power electrical equipment” over the period of 2012-2019. The limited possibilities of the known methods for the purposes of operational forecasting of pre-emergency situations are shown. The feasibility of developing an intelligent data and measurement system for substations that supply electricity to remote agricultural facilities that uses complex diagnostic methods and provides operational forecasting of pre-emergency situations of transformer substations is justified.

Preventive Maintenance of a k-out-of-n System with Applications in Subsea Pipeline Monitoring

Environmental safety issues are of particular importance when we design and operate underwater transport systems. To ensure the transport systems function safely, special systems to monitor their condition are being created. Underwater pipeline monitoring systems should continuously operate to detect and prevent emergency and pre-emergency situations in a timely manner. The purpose of this article is to demonstrate the possibility of using a mathematical model of a k-out-of-n system to support decision-making in the preventive maintenance of an unmanned underwater vehicle to monitor the condition of a subsea pipeline. The novelty and feature of this study are that we investigate a strategy of preventive maintenance for a model of a k-out-of-n system, where failures depend not only on the number but also on the location of the failed components in the system. The method to solve this problem, based on the distribution of the members of the variational series of the failing components, is also new. Since the distributions of the system component lifetimes are usually known with an accuracy of only one or two moments, we paid special attention to how sensitive the decision making about preventive maintenance is to the shape of the distributions. Numerical examples are conducted in order to support the theoretical investigations of the paper. The results of the study are applied to specific equipment to monitor the state of the outer surface of the pipeline.

Метод оценки пожарной опасности технологии производств нефтегазовой отрасли

Introduction. Fire risk can be assessed qualitatively and quantitatively. A qualitative method for assessing fire hazard of the technological process (risk analysis) involves a detailed consideration of possible deviations from the technological regulations and failures in the production technology. Therefore, it can significantly increase the reliability of the hazard analysis to justify the technical decisions made to improve fire safety of production. Goals and objectives. Quantitative methods for analyzing fire hazard of technological processes and assessing fire risk have a number of significant drawbacks, they use various models, in which not always reasonable assumptions are often made. The use of such methods sometimes casts doubt on the results obtained. Hazard analysis using a qualitative analysis method is a sequential process of identifying violations not only of technological regulations, but also of fire safety requirements, and, consequently, the causes of accidents. Therefore, one of the most important purposes of this process is to check that all fire safety requirements are met. Methods. Method for assessing fire hazard of production technology by analyzing the consequences of "What happens if...?" (qualitative method of fire hazard assessment) allows us to consider problems related to possible causes of damage to technological equipment, the consequences of these causes, and the options adopted in the considered production for their prevention. The method is based on the development of a list of hazards, their division by hazard level and determining the most dangerous situations on this basis. Such a division makes it possible to increase the efficiency of the developed technical solutions that increase the level of fire safety of the production technology. Results and discussion thereof. The article reveals the essence of the method for assessing the fire hazard of production technology by analyzing the possible consequences of violations of technological regulations. The place of this method in the expert assessment of the fire hazard of production is shown and an example of the practical use of the method is given. Conclusion. Qualitative method of assessing fire danger of the technological process can complement quantitative methods, it can be their integral part, for example, when calculating the fire risk of production facilities, and it can act as an independent method for small enterprises in which it is not required to conduct a state expertise of projects, as well as when there is a need to assess compliance with fire safety requirements of the technical solutions adopted at the stages of design and operation of production. Keywords: pre-emergency situations, major accidents, fire safety system, explosion protection of a tubular furnace

АВТОМАТИЗАЦИЯ ПРОЦЕССА УПРАВЛЕНИЯ РАБОТОЙ СТРЕЛОВЫХ ГРУЗОПОДЪЕМНЫХ СРЕДСТВ НА КОЛЕСНОМ ХОДУ

The article discusses the on-board information system that will ensure a safe and steady operation of a wheel-mounted boom lifting equipment. The proposed configuration of information panel clearly demonstrates all changes in the angle of boom-lift body orientation while performing necessary production operations and can prevent pre-emergency situations in time. The processing of logged performance values is a very complex and labor-intensive process. Therefore, authors propose to consider the possibility of using the software to reduce time required for performance analysis. The article deals with an algorithm presented here in the form of a block diagram for serial data acquisition, which allows processing logic chain data transferred from the measurement components. The presented mathematical expressions allow authors to calculate the time intervals required for data acquisition and the duration of experimental data recording for further analysis. The proposed combination of the measurement components of on-board information system includes tilt angle meters, force meters, an information panel, and a voltage maintenance unit. All that measurement components of the on-board information system are space saver and can be easily placed on the body of the boom lifting equipment. The figures and tables presented in the article indicate efforts at the creation and commissioning of the on-board information system for boom lifting equipment. As a result, it should be noted that the proposed on-board information system ensures the reliability of a wheel-mounted boom lifting equipment and it is also reasonable to use it for almost all wheel-mounted boom lifting mashines as well as for hoisting equipment.

Поддержка принятия решений по управлению предаварийными ситуациями на примере установки каталитического риформинга

The article touches upon the problem of reducing the risk of accidents at industrial facilities, which is the priority task of industrial safety management. Currently, accident-free production systems rely on monitoring the process state parameters within the acceptable range and are limited to emergency protection systems, alarms, and locks. However, for complex industrial facilities, it is necessary to recognize pre-emergency situations, which allows predicting the occurrence of an emergency mode and preventing the process from stopping or reducing losses in case of an accident. To solve this problem, a system for managing pre-emergency situations is proposed, which is considered on the example of a catalytic reforming installation. It is based on a method for determining the parametric indicator of the object's state, an algorithm for the proposed system, databases of possible causes of pre-emergency and emergency conditions and a list of measures to eliminate them. This solution allows to set the proximity of the operating mode of the process equipment to the emergency mode, which greatly lowers the risk of accident at the facility, thereby reducing the downtime of the equipment and economic losses.

The Mathematical Approach to the Identification of Trouble-Free Functioning of Mining Facilities

Modern drilling rigs are complexes of high-tech equipment operated in difficult climatic and technological conditions, characterized by sudden spasmodic changes in the process of drilling a well, which contributes to increased wear of drilling components and increases the likelihood of pre-emergency and emergency situations. Drilling equipment has a wide range of characteristics and technological parameters, the values of which are available during drilling due to the use of modern software and hardware systems for processing geological and technological information. In order to single out the most frequent pre-emergency situations in practice and to preliminarily determine the set of signs necessary for their recognition, a corresponding analysis of the complications arising during well drilling has been carried out.

Investigation of the Effectiveness of the Method for Recognizing Pre-Emergency Situations at Mining Facilities

In previous reports, an analysis of the basic mathematical methods used to solve the pattern recognition problem was carried out. The inappropriateness of applying the Bayesian classification and cluster analysis to solve the problem of recognizing pre-emergency situations in the process of drilling a well is shown. As a mathematical apparatus for solving the problem of determining the current state of an object of research by a given set of features, a pattern recognition method based on an artificial neural network is selected. In this paper, an analysis is made of existing approaches to improving the quality of education aimed at improving the efficiency of its functioning. The results obtained in this paper will improve the quality of work of the previously developed modified algorithm for training the pre-emergency classifier based on the back propagation method, which differs from the classical one by the procedure for finding the global minimum of the error function, and its software implementation has been implemented. The work is an integral part of previously published developments presented in the materials of articles in 2-nd, 3-rd and 4-th International innovative mining symposiums (2017-2019).

STRENGTHENING PERSONAL AND COMMUNITY DISASTER SUPPORT NETWORKS OF OLDER ADULTS

The Ecological Model posits a multilevel approach to understanding of and strengthening social networks of community based older adults. We present findings from our intervention, network analysis, and efforts at influencing policy making at the state level to better prepare them for pre and post disaster and emergency situations. At the individual-level, we implemented the Disaster PrepWise program to help community-based older adults develop personal disaster plans. We found increases in personal emergency network size by an average of three non-familial individuals. At the community-level, we evaluated two disaster management networks in Eastern Iowa counties. We found strong collaborations in disaster planning and response among 44 governmental and community-based organizations, but weaker collaborations in supporting older residents, suggesting a need in this area. At the policy-level, we are developing a state-level network of organizations to address policy barriers to effectively support older Iowans.

ОСНОВНЫЕ РЕЗУЛЬТАТЫ ОБОСНОВАНИЯ ПРОЕКТНЫХ ПРЕДЕЛОВ ДЛЯ МАТЕРИАЛА ОБОЛОЧЕК ТВЭЛОВ РУ СВБР-100

One of the key tasks for the reactor SVBR-100 project is substantiation of the core elements performance and efficiency. As part of the R & D program to justify the project, a significant amount of work was performed, which confirmed the corrosion resistance of the material of fuel rod claddings (ferric-martensitic (FM) steel) on the basis of 50 thousand hours, the consequences of deviations of the oxygen regime of the coolant from the optimal values were considered. Paper presents the main results of the analysis of fuel rod claddings loading conditions under normal operation, in violation of normal operating conditions and in conditions of hypothetical emergency overheating. It is concluded that the main mechanisms of damage to equipment and core elements in emergency and preemergency situations are associated with the degradation of strength properties with increasing temperature, while corrosion-erosion processes that accelerates with increasing temperature proceed relatively slowly and are limited in time of exposure. Based on the experimental data obtained in the justification of the SVBR project, the nature of the most dangerous emergency processes and the analysis of their consequences, the paper presents proposals for the formulation of key safety criteria for lead-bismuth reactor plants. The approach is based on the establishment of the maximum permissible temperature-time dependences and/or calculated residual deformations of fuel rod claddings made of FM steel.

ОПРЕДЕЛЕНИЕ КОМПЛЕКСНОГО ПОКАЗАТЕЛЯ ТЕХНИЧЕСКОГО СОСТОЯНИЯ ОБЪЕКТА НА ПРИМЕРЕ БЛОКА СТАБИЛИЗАЦИИ УСТАНОВКИ КАТАЛИТИЧЕСКОГО РИФОРМИНГА

Fail-safety taken as a factor of completeness of using the resources of the production facility is important for characterizing the technological process. In most modern automated process control systems the above factor is implemented by means of the emergency protection system which allows to avoid the progressing emergency. However, such measures significantly increase the downtime of process equipment, since the possibility of developing pre-emergency and emergency situations when combining several permissible and close to emergency values of parameters is not taken into account. To solve the problem of reducing machinery downtime, a method for determining the object state indicator has been proposed. It takes into account all variants of the influence of technological parameters on each other as well as their combinations leading to the emergency progress. As well, the proposed solution helps to set the proximity of the operating mode of the production equipment to the threshold emergency, which greatly reduces the risk of emergency in situ, thereby reducing equipment downtime and economic losses. The method of determining the indicator of the state of the object is considered on the example of the stabilization block of hydrogenate catalytic reforming unit.

Modeling of dynamic stability of the well deepening process based on the catastrophe theory

Theoretical aspects of the catastrophe theory were considered and the possibility of application of the catastrophe theory methods in estimation of actual data of geological and technical control of the well deepening process were described. A method for recognizing dynamic conditions of well deepening was studied for the purpose of controlling this process. Expediency of using not only the R. Thom’s elemental catastrophe of the «gather» type but also phenomenological Vapor Pressure model has been proven. As a result of the study, such feature as «the time of drilling 1 m of rock» has been determined to recognize dynamic stability of the process which is prone to stepwise changes. The main arguments for application of the catastrophe theory regarding modeling of dynamic stability of the well deepening process were determined. It was shown that behavior of the system in a catastrophic state can be described not only by a canonical cubic equation solution of which is performed according to the Cardano formulas but also by a phenomenological model based on the principles of holistic approach. Using the holistic approach to solving the problems of modeling dynamic stability of wells, a structure of basic phenomenological mathematical model of dynamics of catastrophe development was proposed. It has been proved that at the initial stages of emergency development when an increase in the time spent on drilling one meter of rocks in the well is observed, dynamics of emergency development can be simulated with the help of the proposed phenomenological mathematical model. With further deepening of the well when there is a decrease in time spent on drilling one meter of rocks, dynamics of the catastrophe development can be described by this law but the model coefficients and their signs will be different. It has the ability of identifying the model parameters with a single algorithm as well as predict the occurrence of emergency at the stage of its development. This helps to prevent complications and accidents in the process of well deepening. According to the simulation results, theoretical inferences on the choice of the model type optimal for describing emergencies in the well deepening process were confirmed and it was established that the proposed phenomenological model is adequate to real processes. At the same time, it is necessary to adhere to the basic principles of the catastrophe theory which makes it possible to provide effective forecasting and detection of pre-emergency situations and complications that arise in the well deepening process. The obtained data are useful and important because they make it possible to improve the mathematical and software system of automated control of the well deepening process and reduce accident rate in drilling.

Development of 3D Atlas of Metalworking Equipment

The paper is dedicated to solving the problem of developing innovative educational systems able to train personnel of complex and dangerous manufacturing industries (such as in metallurgy) to control the process not only under regular conditions, but in emergency and pre-emergency situations as well. At that, such educational systems shall transform training of future and current engineers into a professional activity, model both subject matter and social content of their professional labor. Key characteristics of a 3D atlas of equipment as an educational system are given, as it provides immersion of trainees into professional environment. Requirements for such systems are defined (functional, information, software and technical). Stages of development of a 3D atlas of equipment as an automated system are given, allowing one to get closer to yet another problem that of IT specialist training so that they are able to design, implement and deploy such systems.

Development of Tools for the Analysis of Pre-Emergency Situations on the Drilling Rig Based on Neural Network Technologies

Today complications during drilling and operation of oil and gas wells are unavoidable. Most of them are the result of violation of technological discipline (technology), some are due to insufficient knowledge of geological and physical conditions (especially in exploratory drilling), a lack of understanding of the causes of the phenomena preceding the complication. Sometimes performers in performing complex technological operations go to the so-called “justified” risk, as a result of which complications and accidents occur. It should be taken into account that the failure of the well even for a short time - the loss of oil and gas production. Therefore, the development of modern methods for their detection, prevention (prevention) and methods to combat their consequences is an urgent task.

Drilling Rig Operation Mode Recognition by an Artificial Neuronet

The article proposes a way to develop a drilling rig operation mode classifier specialized to recognize pre-emergency situations appearable in commercial oil-and-gas well drilling. The classifier is based on the theory of image recognition and artificial neuronet taught on real geological and technological information obtained while drilling. To teach the neuronet, a modified backpropagation algorithm that can teach to reach the global extremum of a target function has been proposed. The target function was a relative recognition error to minimize in the teaching. Two approaches to form the drilling rig pre-emergency situation classifier based on a taught neuronet have been considered. The first one involves forming an output classifier of N different signals, each of which corresponds to a single recognizable situation and, and can be formed on the basis of the analysis of M indications, that is using a uniform indication vocabulary for all recognized situations. The second way implements a universal classifier comprising N specialized ones, each of which can recognize a single pre-emergency situation and having a single output.