State Of Technical Objects Research Articles

КОМП'ЮТЕРНА МОДЕЛЬ ДОСЛІДЖЕННЯ ІНФОРМАТИВНОСТІ КРИТЕРІЮ СТЬЮДЕНТА

The state of technical objects can be checked by comparing the average values ​​of samples of measurements of their parameters. Non-parametric statistics allow you to draw statistical conclusions, in particular, to evaluate distribution characteristics and test statistical hypotheses, without, as a rule, weakly justified assumptions that the distribution function of the sample elements belongs to one or another parametric family. For example, it is widely believed that statistical data often follow a normal distribution. Meanwhile, the analysis of practical results, in particular, measurement errors, always leads to the same conclusion - in the vast majority of cases, real distributions differ significantly from normal ones. In the tasks of non-destructive testing, technical diagnostics and monitoring of the state of objects, non-parametric statistics are the basis for research and decision-making about suitability or quality. Despite the large number of publications dedicated to research on specific issues of the use of non-parametric statistics methods, the internal structure of this scientific direction remains an actual problem even at the present time. Most often, in practice, the problem of belonging of samples to one general population is solved. One of the main verification criteria is the Student criterion. But, in order to use them, it is necessary to check samples for "normality". Uncritical use of the normality hypothesis often leads to significant errors, for example, when rejecting the results of observations (outliers), during statistical quality control, and in other cases. If the samples are short (n⩽20), and the measurements are normal random variables, then classical mathematical statistics suggests solving this problem with a modified Student's test [1]. The power of this criterion is no worse than the classic Student's criterion. This is especially evident with short samples (n≤20). In this article, by conducting computational experiments, the informativeness of the modified and classic Student's criterion was compared. The study was conducted for samples of random variables with three distribution laws - logistic, exponential and Rayleigh. The result showed that the modified Student's test has more power than the classical test. But, as expected, both criteria are sensitive to the symmetry of the distribution law - the greater its asymmetry, the greater the error of accepting the null hypothesis.

Methods and Algorithms for Solving the Problem of Early Diagnostics of Technical Objects Using Data Mining Methods

Русский Main page New issue Archive of articles Editorial board For the authors Publishing house ABSTRACTS OF ARTICLES OF THE JOURNAL "INFORMATION TECHNOLOGIES". No. 9. Vol. 28. 2022 DOI: 10.17587/it.28.475-484 G. S. Veresnikov, Dr. Tech. Sc., Leading Researcher, A. V. Golev, Junior Researcher, A. M. Moskovtsev, Engineer, M. P. Martirosyan, Engineer, Institute of Control Sciences V. A. Trapeznikov Academy of Sciences Senior Researcher, Moscow, 117997, Russian Federation Methods and Algorithms for Solving the Problem of Early Diagnostics of Technical Objects Using Data Mining Methods We are seeing a huge increase in the productivity of technical facilities. But as soon as the object is used for its intended purpose, its technical resource begins to be consumed. Early diagnostics and condition detection are important for reliable and safe operation of technical facilities. The results of early diagnostics are used both for prevention of emergency situations and for operation of technical objects according to their condition. In this article, the task is to analyze the methods and algorithms of data mining used in the tasks of determining and predicting the state of technical objects. Neural networks, decision trees, growing pyramid networks, metric algorithms, and the support vector method are considered. Advantages and disadvantages of data mining methods and algorithms are given. Special attention is paid to algorithms and methods for identifying informative features in empirical data, in particular, filtering, projection, and wrapping methods. The use of these methods and algorithms is important to simplify the models used to classify the States of technical objects and improve the accuracy of diagnostics. Analysis of the world scientific literature has shown the relevance of using methods and algorithms for data mining in integration with methods for identifying informative features. These methods are usually used in conjunction with wrapper methods and filters to improve diagnostic accuracy and condition detection of technical objects.

EXTERNAL CRITERION OF STABILITY OF INTRA-MULTIPLE DISTANCES IN TASKS OF DIAGNOSIS OF STATES OF TECHNICAL OBJECTS

The purpose of the research is adaptation of biclasticization criteria, which have the properties of external complement to the problems of classification of states of complex technical objects in the field of computer engineering. The principles of inductive modelling of complex systems, in particular, the principle of external complementarity, as well as the methodology of the theory of pattern recognition, methods of inductive cluster analysis, mathematical statistics are applied. The construction of the criterion of stability of intra-multiple distances is based on the schemes of known criteria of self-organization of models, in particular the criterion of model inconsistencies, which are widely used in multi-step image recognition algorithms with intelligent choice of optimal results. The paper proposes the application of the criterion of stability of intra-multiple distances in the problems of diagnosing the state of technical objects, in particular, in the field of computer engineering. Since the application of such a criterion requires the presence of a target feature, one of the options for splitting the original experimental database into two subsets has been adapted: a subset of target features and a subset of input parameters. The concept of intra-multiple distances is extended to the application of algorithms of optimal complexity in the criteria of self-organization algorithms. Intelligent algorithms for self-organization of models of optimal complexity can be used to increase the reliability of computer systems.

SELECTION OF A SET OF INDICATORS FOR ASSESSING THE OBJECT PERFORMANCE OF A FAULT

The continuous complication of technical objects and the growth in the degree of automation of the control process bring to the fore the problem of optimal organization of the operation of complex technical objects. An important role is assigned to the definition of the state of objects, which, due to the influence of external and internal factors, changes over time. Technical diagnostics are responsible for resolving all issues related to determining the state of technical objects and the nature of its change over time. Technical diagnostics deals with the study of methods that determine the actual state of technical objects. This provision causes fundamental differences in the methods of research of technical objects used in the theory of reliability and in technical diagnostics. Possible malfunctions are divided into element malfunctions, which are defined as unacceptable quantitative changes in any parameter (characteristics) due to irreversible physical and chemical changes, and object malfunctions, which are interpreted as unacceptable quantitative changes in parameters (characteristics) or changes in structural relationships in the object. The process of determining the actual state of the object provides for the existence of a reasonable program and specified diagnostic algorithms. The diagnostic algorithm is a set of operations performed in a certain sequence in order to solve a specific diagnostic problem. The diagnostic program is a sequence of operations (algorithms) determined in time to establish the actual state of the object and the nature of its change. In this case, the initial data are the sequence of operations, the duration of each operation, the number of operations performed in parallel, and the required power of energy sources. Performance conditions can be formulated on the basis of an analysis of the model of the object being diagnosed or obtained on the basis of an experiment in the study of a real object. In this case, the performance conditions are defined either as restrictions on changes in dynamic and static characteristics or a set of object parameters, or as a requirement to perform specified functions in accordance with a certain logic. Analysis in the complex plane and the formulation of performance conditions as a requirement to find the roots of the transfer function in a given area make it relatively easy to make the transition to setting performance conditions in the time and frequency domains or in the area of controlled parameters. The health of an object is determined by its state. To assess the state of an object, it is necessary to plant it or perform its work functions, or respond to special control actions. In the first case, a so-called functional test will be carried out, in the second case, an assessment by parameters or characteristics. When checking for functioning, as a rule, there is no quantitative assessment and performance is determined by the compliance of the movements of the executive bodies, the amount (volume or weight) of the working fluid, products and positions of the switching bodies with the values set for the operating mode of the object. In addition, during the operation of the object, its performance can be assessed indirectly by the level of noise, the nature of the radiation, and the energy consumed. When evaluating the performance, as the parameters of the object, one can consider the parameters of the elements, the coefficients of the transfer function or the parameters of the dynamic links. When evaluating the performance of an object by characteristics, one can directly compare the actual characteristics with the reference ones, use integral estimates or compare individual indicators of static or dynamic characteristics. As indicators of time characteristics, quality indicators known from the theory of automatic control can be considered: decay time, rise of the first surge, delay, reaching a given level, period and number of oscillations, overshoot, etc. Frequency characteristics can be compared by maximum amplitude, bandwidth, frequencies cutoff and maximum. Parameters or characteristics can be evaluated separately at the facility or by comparing the response of the facility and an equivalent model to the same impact. In this case, it becomes necessary to build a model that is equivalent to an object based on controlled parameters or characteristics. Keywords: Technical diagnostics, object analysis, diagnostics, object health, resonant frequency, fault finding algorithms, decay time

Method, models and information technology of decision making about the state of technical objects under non-stationary input influences

There is a significant increase in the amount of measuring information at complex and large technical objects, such as bridges. Decision making about these objects states under non-stationary input influences is a difficult task. The article proposes to make the transition from single-channel information processing to multi-channel one. Each channel processes one of the Hilbert-Huang modes, into which each realization of the nonstationary signal decomposes. It is shown that the first three modes of decomposition are often enough, which in most cases create a stationary process. If a mode is non-stationary, it is possible to decompose it into these modes. The final decision according to statistical criteria is made not on realizations as it is traditionally carried out, but on Hilbert-Huang modes.

Акустический сенсор для оценки состояния производственного оборудования

An important trend in the development of industry is the development of digital models of industrial facilities, the work of which is based on information coming from sensors. This allows you to optimize functionality, predict the technical condition of objects, which is especially important, for example, in the field of metallurgical production, where forced stops are accompanied by huge losses. The sensors themselves are also modeling objects, because they need to adapt to rigid production conditions in which their own shortcomings are manifested, while the correct introduction of corrections for environmental conditions, diagnostics and self-diagnostics, which are impossible without building various types of sensor models, is important. The purpose of the work is to deve¬lop a universal discrete model of an acoustic sensor suitable for receiving and emitting acoustic signals. Methods. The work used methods of classical mechanics and mathematics, vibration theory, generalized functions, distributed systems, and mathematical programming methods were used to provide calculations. Results. The main result is a universal discrete model of a sensor with a working element in the form of a round plate, which by choosing parameters can be transformed into a model of a unidirectional dynamic microphone with a flat membrane or a radiator with a focusing spherical element. It is shown that on the basis of the model it is possible to synthesize narrow-directional radiation diagrams and thereby obtain the necessary spatial selectivity and noise immunity of measurements. Conclusion. Calculations made using the proposed model correspond to the known results of acoustics. Verification of the discrete model using a natural sample showed a high accuracy in determining the resonant frequencies and forms of oscillation of the sensor.

CURRENT STATE OF SCIENTIFIC AND TECHNICAL DEVELOPMENTS IN THE FIELD OF IMPROVING THE EFFICIENCY OF VIBRATION EQUIPMENT AND TECHNOLOGIES

The article considers the state of scientific and technical developments in the field of improving the efficiency of vibration technology. Production activity in most branches of industrial production is provided by the work of various technological machines and vehicles. The operation of machines, equipment, mechanisms, apparatus and devices in the conditions of the need to ensure high productivity is often accompanied by significant dynamic loads, vibration processes and manifestations of shock interactions of machine elements. Ensuring the reliability and safety of machines requires at all stages of their life cycle serious attention to compliance with certain restrictions on the parameters of the dynamic state of technical objects, the development of methods and means of assessing control and management of dynamic interactions. Modern mechanical engineering is a scientific basis for solving the main problems of machine dynamics, which, in general, is based on scientific potential created by domestic and foreign scientists in the field of theoretical and applied mechanics, theory of mechanisms, dynamics and strength of machines, development of scientific directions in automatic control theory. applied system synthesis, etc. The results of scientific research are reflected in the works of famous scientists. The formed practice of pre-design researches of the created machines, the equipment and the equipment is based on wide use of means of mathematical modeling, application of means of computer engineering. The choice of equipment in production is based on cost, productivity, size, energy consumption, etc. In this regard, there is a question of the need to find and develop new approaches, methods and means to ensure the efficiency and reliability of technological machines and equipment.

A System for Noise Control of the Technical Condition of Railroad Bridges and Tunnels in Seismically Active Regions

The authors analyze the technical condition of objects of railroad communications with modern bridges, tunnels, stations, overpasses, crossings and power installations. It is noted that, based on the specific features of such objects, control of their technical condition in most cases is carried out at certain intervals. At the same time, existing continuous control systems do not always adequately assess the technical condition of rail infrastructure objects due to the presence of additional noises in the processed signals at the time when a malfunction occurs. In this regard, one of the possible options is proposed for "continuous" monitoring of the beginning of changes in the technical condition of railroad tracks by means of noise technologies. It is pointed out that when the technical condition of rail infrastructure changes, vibration signals caused by the impact of rolling stock contain noises in addition to the useful component. The use of correlation and spectral analysis technologies, as well as other traditional methods does not allow ensuring the adequacy of the control results, due to the influence of the noise on useful vibration signals. Therefore, technologies are proposed for split analysis of the useful signal and the noise received from vibration, as well as for forming informative attributes of identification of the technical condition of rail infrastructure. In this case, the estimates of the characteristics of the useful signal and the noise are used as the main carrier of diagnostic information. Due to the simplicity and reliability of the developed theoretical algorithms, the implementation of the technical equipment and its installation in all objects of the railroad track present no particular difficulties. At the same time, the implementation of the Noise system will ensure real-time control of the beginning of changes in the technical condition of railroad tracks during the movement of the rolling stock. This, in turn, will allow timely detection of malfunctions, significantly enhancing the safety of passenger and cargo rail transportation.

The method of aviation systems diagnostics according to the admissible level of non-failure operation probability

The paper presents the methods of forecasting reliability of the created devices, design of devices with the given reliability and comparison of reliability of various aviation systems. Calculated relations at various types of redundancy in tests, prolongation of service life of blocks of aircraft, the basis of which is methodology of estimation of residual resource are resulted. The existing methods of reliability analysis are systematized and studied. The problems of uncertainty of information on input data at calculations by classical methods are stated. It is postulated that the principle of comparability of results of quantitative estimations of technical systems assumes the use of uniform composition of initial data for a certain reporting period of time, unity of generalized and private indicators used as well as unity of assumptions and limitations accepted. The application of general and elementary formulation of the state estimation of complex mechanisms with the use of diagnostic matrix and recognition theory to determine the state of technical objects is shown. Stages of the general process of object diagnostics are described, which consist in determination of parameter changes at influence on object elements and further processing of the obtained results using synthesis and analysis methods.

Method for calculating the insulation of airborne sound by enclose from volumetric-block buildings

This research paper provides a method for calculating airborne sound insulation by encloses from volumetric-block buildings. The choice of the most suitable construction solution for the technical condition of objects at the design stage for building elements should primarily provide insulation from sound and a safe mode inside buildings, in which protection conditions in the combination of energy efficiency and stability should be taken into account, as well as competent decisions and its impact on the construction process buildings. Numerous scientific studies show the negative effect of sound on human health by the occurrence of various diseases such as cognitive impairment of the fetus in reproductive people, sleep disturbances, tinnitus, irritation, and dysfunction of some human organs. Therefore, sound exposure should be considered a source of inconvenience and a source of harm to human health. Sound waves collide with the surfaces of enclosing structures, causing them to vibrate and transmit the negative effects of the air around them in adjoining rooms, in which, from the point of view of regulatory requirements, in many cases, it does not meet the requirements, since comfort also depends on the design and sound insulation of the volumetric-block buildings. Many of these problems are easily solved at the design stage by choosing the right design solution and calculating the soundproofing qualities of the enclosing structures. In particular, one of the main tasks at the design stage is the development of structural solutions for internal enclosing structures that have a relatively small mass that allows reducing the load on the supporting structures of the building and plummets the material consumption of construction. At the same time, it is necessary to ensure compliance with the regulatory requirements for the isolation of airborne sound of enclosing structures.

Multilevel model of time dependences of acoustic emission parameters as the basis for nanodiagnostics of the state of technical objects

The method of acoustic emission (AE) and the information-kinetic approach to AE diagnostics are identified as the most promising from the point of view of observing the process of growth of damage and optimization of production technologies. Based on a multi-level model of the time dependence of AE parameters, estimation of elastic homogeneous fracture intensity parameters of representative structural elements of a product and universal strength nanoconstants, the approach combines the traditional experimental way of resource estimation and kinetic representations of fracture. This allows to separate the effect of macro- and nano-factors on the AE of the material, variously related to the strength and acoustic emission activity of the material. A multilevel model and an informational-kinetic approach to acoustic emission diagnostics are described, combining nano-, micro- and macro-factors affecting acoustic emission activity, reliability of technical objects and methods for assessing their resource. On the example of a welded pressure vessel, the implementation of the method of its nano-diagnosis is considered. The possibility of effective resource estimation of various technical objects based on the information-kinetic approach to their acoustic emission diagnostics is shown. As a methodological basis, a multilevel model of the time dependences of the AE parameters is taken, which describes their behavior under conditions of strength and metrological heterogeneity.

Adaptation of fuzzy inference system to solve assessment problems of technical condition of construction objects

The main task, the solution of which the work is focused on, is the automation of the fuzzy inference system, which is one of the subsystems of the system for assessing the technical condition of construction objects. The proposed assessment system is assigned to services that specialize in conducting construction and technical examinations. The process of conducting examinations in this area is accompanied by uncertainties of a different nature, and the production activities of specialists are often based on heuristics. That is why, the object of research are models and tools that can function in fuzzy conditions. To automate expert activities in the field of assessing the influence of external factors on the technical condition of compacted urban areas, a specialized assessment system has been designed based on knowledge and an artificial neuro-fuzzy network of the Takagi-Sugeno-Kang category. The use of neuro-fuzzy models for fuzzy inference makes it possible to automate the process of obtaining logical conclusions from input according to fuzzy rules specified by experts. At the same time, settings for membership functions can be carried out using artificial neural networks. The Takagi-Sugeno-Kang fuzzy neural network is designed to solve this problem. The feasibility of using this model to solve the problem of assessing the technical condition of construction objects with damage is justified by its ability to solve the problem of fuzzy classification. The second main criterion for choosing this model is the ability to set the rules by the input function, since under the conditions of compacted urban development, the factors affecting the external environment on the technical condition of objects are complex non-linear. The principle of adaptation of the fuzzy inference system is shown by the example of fuzzification of environmental influences caused by vibrations of a different nature. The studies carried out in the work, unlike the previous ones, expand the knowledge base of the system by presenting information about the real state of the environment in which the construction objects operate. It is expected that the use of the Takagi-Sugeno-Kang artificial neural network will significantly reduce the influence of the human factor on the performance of construction and technical examinations performed under conditions of compositional uncertainty. The practical significance of the work is to reduce the timing and increase the reliability of the assessment of the technical condition of construction objects with damage of a different nature

THE USE OF NEURO-FUZZY MODELS IN EXPERT SUPPORT SYSTEMS FOR FORENSIC BUILDING-TECHNICAL EXPERTISE

The paper is focused on solving the problem of assessing the impact of repair-building works on the technical condition of objects near which these works were or are being carried out. Particular attention is paid to the analysis of the problems that accompany the creation of expert systems for supporting forensic building-technical expertise. The main aim of the work: conceptual modeling of an expert system for supporting forensic building-technical expertise. Object of research: the process of execution of forensic building-technical expertise and expert research. Solved problem: automation of a system capable of functioning in conditions of fuzzy uncertainty caused by the non-uniformity of the logic of the process of performing forensic building-technical expertise and the ambiguity and inconsistency of the information provided for research. Main scientific results: a model of a knowledge-based system is proposed and the use of neuro-fuzzy networks is justified to solve the problem of supporting the decision to assess the impact of repair-building works on the technical condition of the object, which has become the subject of expertise. Field of practical use of research results: forensic activities in the framework of building-technical expertise to determine the possible causes of deterioration in the technical condition of structural elements of buildings and their individual premises. Innovative technological product: a support system for forensic building-technical expertise based on knowledge and neuro-fuzzy models. Scope of application of an innovative technological product: forensic and investigative practice in resolving issues requiring the use of special knowledge in assessing the impact of repair-building works on the technical condition of nearby facilities.

Information Value Measure for Optimization of Flexible Diagnosis Programs of Technical Objects

Existing methods of calculating of the value of diagnostic information circulating in the automated systems of monitoring of technical condition of objects do not take into account "losses" ("gains") resulting from making “wrong” decisions when identifying this state. The purpose of the work is to develop an algorithm that allows to solve the problem of recognizing the technical state of the object being analyzed by means of dynamic programming, the value of the diagnostic information as an optimized indicator being used. The solution to the optimization problem of a diagnostic procedure is based on the use of a measure of the information value proposed by R. L. Stratonovich. It is modified according to the subject area of the technical diagnostics and in the case when the diagnostic features presented in the form of intervals on the real numerical axis are used. The maximum value of the diagnostic information is achieved by minimizing the average "losses" (maximizing the average "gains") obtained when performing tests of diagnostic signs in the process of recognizing the technical condition of an object. To solve the problem, a recurrent expression possessing a scientific novelty has been proposed. It allows to calculate the value of the information obtained when performing tests of diagnostic signs in each of the analyzed information states of the diagnostic process. In the process of the diagnostics program implementation when recognizing the technical condition of the object both “losses” and “winnings” are possible. The difference between their a priori and a posteriori means values characterizes the value of the diagnostic information numerically. The magnitude of the information value indication depends on the probabilities of the results of the diagnostic signs checks and is proportional to the difference between the a posteriori and a priori probabilities of achieving the diagnostic goal. By using the proposed solution, it is possible to synthesize the flexible diagnostics program that is optimal according to the maximum value of diagnostic information in the form of a oriented graph or sets of tests in proper sequence of their execution. This is necessary in order to recognize the specific technical state in which the object is located. The implementation of the algorithm developed is possible in the software and algorithmic support of the automated systems for monitoring the state of complex technical objects.

METHOD OF RISKS CONSIDERATION IN PRODUCTION OF ELECTRONICS

In the article it is discussed the possibility of using the Failure modes and effects analysis (FMEA) to determine the potential risks and threats in the production of electronic products, as well as their causes. In order to develop adaptive solutions to counteract unpredictable disturbances that inevitably arise in various technological processes, the analysis of the possible abnormal state of microclimate control systems in clean rooms, formulated preventive actions to eliminate violations of microclimatic parameters that pose a threat to ensure quality indicators of the production process. The developed method of formation of pre-emptive actions aimed at assessing and predicting the technical condition of objects, is designed to provide complete information support for management decisions to improve the efficiency of the process, as well as to reduce the number of failures of engineering equipment.

To the theory analysis of tightness of tank of pressure testing

This article studies the process of relaxation of the pressure in a tank with the damaged area of the wall after pressure-testing. The authors use different methods for the diagnosis of the technical condition of objects of petroleum products storage. Pressure testing is one of nondestructive methods. The rate of pressure decrease is characteristic of the system tightness. This article studies the cases of ground and underground location of the tank. Pressure testing involves excess pressure inside of a tank and observing its decrease. Over time, one can assess the integrity of the system. This has required creating mathematical models to account the filtration of the liquid depending on the location of the tank. The results include the analytical solution of the task and the formulas for describing the dependence of the relaxation time of pressure in the tank from the liquid and soil parameters, geometry of the tank, and the damaged portion of the wall. The two- and three-dimensional cases of liquids filtration for the case of underground location of the tank were considered. The results of some numerical calculations of the dependence of reduction time and the time of half-life pressure from the area of the damaged portion of the wall were shown. The obtained solutions allow assessing the extent of the damaged area by the pressure testing with known values of tank, liquid, and soil.

Analysis of measurement points sensitivity of vibration signals on the stand of jet engine

The diagnostic testing of internal combustion engine can be made by using working processes and methods which take advantage of leftover processes. Working processes give information about general condition of internal combustion engine. Leftover processes give information about condition of particular subassemblies and kinematic couples; hence they are used as autonomous processes or as processes supporting other diagnostic methods. Methods based on analysis of vibrations and noise changes to determine technical condition of object are named as vibroacoustic diagnostics. In papers about vibroacoustic diagnostics of engine, problems connected with difficulty to select test point and to define diagnostic parameters containing essential information about engine’s condition, are most often omitted. Selection of engine’s working parameters and conditions of taking measurements or recording vibration signal are usually based on references, researcher’s experience or intuition. General assumptions about taking measurements of signal closest to its source are most often used. This paper presents a new approach to vibroacoustic diagnostics of jet engine. Selection of measurement points of vibration signals on the basis of tests stand results was suggested and perform a sensitivity analysis of measurement points on the engine support.

Экспериментальное определение быстродействия пленочного термосенсора в системах пожарной сигнализации

An early detection and rapid transmission of the message about a fire plays an important role in reducing the severity of the consequences from fires, which ensures the timely adoption of measures for its liquidation. Thus, the purpose of this article is to review issues of applying thin-film resistance thermometers as the primary high-speed detectors in fire alarm systems. This opens up great opportunities for the development of multiband systems based on microelectronics technology. Thin film thermosensors on a massive substrate combine the functions of a threshold sensor as well as a measuring transmitter operating in the thermal finder mode. As a threshold sensor, the thin-film termosensor is, in fact, a time sensor (signal sensor) when the abrupt change in the temperature of the control surface or the heat flow is used as the alarm information. As the thermal finder of fast processes, film thermosensors allow, in addition to detection of existence of “emergency” situations (fire-flash, the combustion front, shock wave, detonation, the beginning of explosive reaction of gas mixture, etc.), to monitor process conditions, to determine the degree of risk and the dynamics of the anomalous process, to monitor the thermal state of technical objects and the environment. The results of the conducted field tests using a specially designed optical stand allowed us to make an unambiguous conclusion about that film thermosensors, with a time response less than one microsecond, can perform the function of a very early detection of fire or explosion on various potentially dangerous objects. Thus, the use of film thermosensors in radio systems for early detection of fire and other emergencies, will allow radically change the existing situation for the protection of people and objects from fire and accidents.

The systematization, development, and application of grid-system technologies

This article systemizes grid systems of different types according to their main categories and features that determine their technical and functional possibilities. It considers intelligent grid systems and itemizes the directions by which the present-day models, algorithms, and tools of the software for grid systems, including those with elements of artificial intelligence, are developed. It supplies information about the implemented intelligent software-hardware systems for monitoring and the appraisals of the technical condition of objects in national and regional networks of the mainline power supply.

Experimental method for the selection of points of measurement diagnostic vibration signals on internal combustion engine

The diagnostic testing of internal combustion engine can be made by using working processes and methods which take advantage of leftover processes. Working processes give information about general condition of internal combustion engine. Leftover processes give information about condition of particular subassemblies and kinematic couples; hence they are used as autonomous processes or as processes supporting other diagnostic methods. Methods based on analysis of vibrations and noise changes to determine technical condition of object are named as vibroacoustic diagnostics. In papers about vibroacoustic diagnostics of engine, problems connected with difficulty to select test point and to define diagnostic parameters containing essential information about engine’s condition, are most often omitted. Selection of engine’s working parameters and conditions of taking measurements or recording vibration signal are usually based on references, researcher’s experience or intuition. General assumptions about taking measurements of signal closest to its source are most often used. This paper presents a new approach to vibroacoustic diagnostics of internal combustion engine. Selection of test points of vibration on the basis of impact tests results was suggested and performed a sensitivity analysis of measurement points on the cylinder head, the force impulse.