Research of diagnostic models of subsystems of power supply of radioelectronic means

The complex indicator of the reliability of electronic means - the readiness factor - significantly depends on the average recovery time. At the same time, the largest labor costs are spent by repair specialists on finding a faulty element. Diagnostic repair support depends on the models used in the development of defect detection algorithms. The most common use of diagnostic models in the form of a graph of information and energy connections, which consists of three types of structures: sequential connection of elements, converging and diverging. The latter did not receive the necessary research. In the article as a result of research of influence of forms of the graph of information and power communications on indicators of quality of diagnostic maintenance of subsystems of power supply of radio electronic means analytical dependences of quantitative estimation of the controlled variables on average recovery time are received for the first time. This allows to improve the quality of diagnostic support of existing and promising samples during their design. Minimization of diagnostic errors makes it possible to verify the feasibility of using diagnostic and metrological support during the current repair of electronic devices by the aggregate method, which reduces the recovery time, especially in the field. Depending on the volume of initial data, possible methods for quantifying the probability of the preferred choice of branches of power subsystems of radio electronic means, which also reduces the average recovery time by checking primarily the least reliable and do not require much time to perform checks and troubleshooting. The obtained results should be used in improving the diagnostic and metrological support of power supply subsystems of existing electronic devices and its development for promising samples in order to improve the quality of maintenance, regardless of the structure of choice.

Adapted Method of Radiation Response Function Calculation for Development of High-Sensitivity Reference Meters Based on Scintillation Detection Units with NaI(Tl) Crystals for Dosimetry of Low-Intensity and Near-Background Levels

Metrological support of photon radiation fields of low-intensity and near-background levels (0.04–100 μSv/h (μGy/h)) by ambient equivalent dose rate or kerma rate in air using scintillation detectors with NaI(Tl) crystals looks promising and in demand in dosimetry, but nontrivial due to the complex dependence of efficiency registration of gamma quanta from energy. The solution of such problems with the use of these detectors can be based on the use of the radiation response functions, which are functionals of the energy distribution of the radiation field fluence. The paper proposes a method for calculating the radiation response function adapted for solving metrological support problems for creating high-precision dosimetric measuring instruments based on scintillation detection units with NaI(Tl) crystals.

METROLOGICAL SUPPORT OF GEODETIC WORKS IN THE ROAD ROUGHNESS MEASURING

Most of the transport and operational indicators that directly affect the road roughness depend on the roughness of coverage. Therefore, the control and timely monitoring of the road roughness is an extremely important issue that needs the attention of road maintenance services. At monitoring of the road roughness it is most expedient to use a technique of leveling of a covering. The method of leveling the coating provides more detailed information about the coating and allows you to determine the smallest deformations on the road coating, which may be at the first stage of their development, especially at that stage of their development, and show roughness and various parameters. One of the main tasks of measurements in the process of performing geodetic works is not only to obtain the measurement result, but also to assess its reliability. The required quality of instrumental measurement can not be achieved without adhering to the principles of unity and the required accuracy of measurements, so much attention should be paid to the metrological support of geodetic works. The purpose of this article is to analyze the metrological support of geodetic works in determining the pavement roughness and substantiation of the required accuracy of measuring the non-rigid pavement roughness. On the basis of dependences for determining the coefficient of dynamic load on pavement and the correlation between the pavement roughness and the coefficient of dynamic load and on the basis of experimental data, the necessary accuracy of measuring the non-rigid pavement roughness is substantiated. Based on the analysis, it was found that the accuracy of determining the height of the irregularities should not exceed 0.5 mm, for which it is necessary to use optical or electron-optical levels.

ВИДИ МЕТРОЛОГІЧНИХ ХАРАКТЕРИСТИК І СКЛАДУ РОБІТ З ЇХ ВИЗНАЧЕННЯ НА ОСНОВНИХ СТАДІЯХ ІСНУВАННЯ КОМПОЗИТНИХ КОНСТРУКЦІЙ АГРЕГАТІВ ПОВІТРЯНИХ СУДЕН ТРАНСПОРТНОЇ КАТЕГОРІЇ

It is shown that the development of the concept of metrological support for the creation of composite structures of aircraft aggregates of the transport category and their support at all stages of the existence of an aircraft should be based on the formation of a complex criterion for the effectiveness of the use of polymer composite materials. It is noted that the effectiveness of a structure made of polymer composite materials is provided by various methods, methods and technical means of metrology. The structure of a complex of studies aimed at developing the concept of metrological support is discussed, the first point of which is to analyze the types of metrological characteristics and the scope of work to determine them at the main stages of the existence of composite structures of aircraft aggregates of the transport category. Based on the analysis of numerous publications on the problem of metrological support of the main stages of creating technical products, the main types of measurements of the metrological characteristics of composite structures of aircraft aggregates of the transport category have been established, and the composition of the nomenclature of works on metrological support of the main stages of the existence of these structures has been determined. 12 main types of measurements of parameters have been identified, on which the whole variety of production physical quantities and the description of the properties and characteristics of structures of aircraft aggregates made of polymer composite materials are based. The composition of the main works on the metrological support of the four stages of the existence of the aircraft is revealed: design, production, operation and disposal of composite structures formed into systems of sequential blocks for performing these works. It is shown that the tasks of metrological support at the facility manufacturers should be solved during the technological preparation of serial production and testing of the installation series of products, and also take into account the peculiarities of aircraft operation and disposal of composite structural elements in terms of work safety and economic efficiency of their results. An enlarged sequence has been established for organizing work on metrological support for measuring the properties of composite structures of aircraft aggregates at aviation enterprises. The results presented in the first approximation provide a solution to practically important aspects of the problem under discussion.

METROLOGICAL SUPPORT OF PETROLEUM PRODUCT TESTING FOR PURPOSES OF CONFORMITY ASSESSMENT

С использованием методов системного анализа обоснована системная цель метрологического обеспечения испытаний нефтепродуктов – получение точной, полной и достоверной измерительной информации о составе и свойствах нефтепродуктов, которая достигается через решение двух частных целей: а) создание условий для получения результатов испытаний с требуемой точностью; б) достижение такого состояния процесса испытаний, которое обеспечивало бы получение точной и достоверной измерительной информации о составе и свойствах нефтепродуктов. Раскрытие первой и второй частных целей образует структуру системы метрологического обеспечения испытаний нефтепродуктов, представляющую собой совокупность традиционных элементов и процессов метрологического обеспечения и процедур управления процессом испытаний нефтепродуктов. В разработанной структуре системы метрологического обеспечения испытаний нефтепродуктов используются как известные общепризнанные элементы и процессы метрологического обеспечения, так и новые элементы и процессы, отражающие специфику процесса испытаний как объекта метрологического обеспечения. В частности, для подтверждения метрологической пригодности методик испытаний нефтепродуктов предложено использовать процедуры валидации и верификации, показана необходимость верификации операторов, проводящих испытания. В целях снижения погрешности испытаний нефтепродуктов обоснована необходимость включения в систему метрологического обеспечения мероприятий по управлению процессом испытаний нефтепродуктов в лаборатории. Показана такая последовательность действий по метрологическому обеспечению испытаний нефтепродуктов, которая позволяет добиться такого состояния процесса испытаний, в котором погрешность получаемых результатов находится в определенных статистически обоснованных границах, а достоверность результатов испытания подтверждается стабильностью значений погрешности. Applying the methods of system analysis, the system goal of metrological support for petroleum product testing is justified; the goal is to obtain accurate, complete, reliable measurement information about the composition and properties of petroleum products, which is achieved via solving two subgoals: а) creating conditions for obtaining the testing results having the required accuracy; б) achieving such a state of the testing progress that would ensure the receipt of accurate and reliable measurement information about the petroleum product composition and properties. The disclosure of the first and second subgoals forms the structure of the metrological support system intended for testing of petroleum products, which is a complex of conventional elements and processes of metrological support and procedures for controlling the process of petroleum product testing. In the structure of the metrological support system under development purposed for petroleum product testing, both well-known and generally recognized elements and processes of metrological support, as well as new elements and processes that capture the specific features of the testing process as a subject of metrological support. In particular, it is proposed to use validation and verification procedures to confirm the metrological applicability of testing methods intended for petroleum products, and the need for verification of operators, who carry out the tests, is given. In order to reduce the petroleum testing inaccuracy, the need to include measures to control the process of petroleum product testing in a lab by way of the metrological support system is justified. The following sequence of actions for metrological support of petroleum products testing is shown; it allows achieving such a state of the testing process, in which the tolerance of the obtained results is within certain statistically adjusted limits and the reliability of the test results is confirmed by the stability of the tolerance values.

Metrological support of maintenance by the technical state of communication means

Modern and prospective communication means are among the most knowledge-driven, high-tech types of industrial products, which are subject to enhanced requirements for quality and efficiency of application. The effective functioning of modern communication means is provided by built-in software, including metrological support. In this paper, we consider the specifics of metrological maintenance of large-scale communication facilities (tens and hundreds of thousands of elements) consisting of separate subunits, the serviceability, maintenance, and recovery of which can be performed autonomously. It is proposed to enhance the efficiency of the by-state-maintenance (also called maintenance by the technical state) by accounting for the specifics of metrological support, establishing an optimal sequence of operations, selecting the measuring instruments in accordance with relevant requirements. To do this, one has to use a combined indicator composed of individual parameters of the tests and the probability of their preferred choice. This allows to assess the technical condition of the communication means with a given probability during a minimal time. In addition, one can estimate the time of maintenance, taking into account the metrological reliability and the probability of correct evaluation of the result of checking the parameters by the measuring instruments. The order of implementation of the obtained results is formalized in the form of an algorithm and an example of their realization is presented.

METROLOGICAL SUPPORT FOR THE VERIFICATION OF MEDICAL INFRARED THERMOMETERS

The paper analyzes two methods of checking medical infrared thermometers – using the black body model and using the gray body model. The use of black body models provides the highest accuracy of temperature reproduction. Direct verification of infrared thermometers is not possible due to the discrepancy between the emissivity value entered in the infrared thermometer and the emissivity value of the black body. In this paper, we propose an algorithm for calculating corrections to the value of the temperature reproduced by the black body. The values of the corrections for different temperatures and emissivity introduced in infrared thermometers are given. Using the gray body model does not require any additional calculations. A model of a gray body with an emissivity from 0.94 to 0.99 has been developed and studied. The advantage of the proposed design is low cost, ease of practical application, and the possibility of simultaneous verification of infrared thermometers with different set emissivity values. For each of the methods, an algorithm for estimating the measurement uncertainty during verification is proposed. The results of the research can be used in testing medical infrared thermometers for type approval and the development of verification methods.