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(1) Background: A new probabilistic physico-chemical model of the drifting key parameter of measuring equipment is proposed. The model allows for the integrated consideration of degradation processes (electrolytic corrosion, oxidation, plastic accumulation of dislocations, etc.) in nodes and elements of measuring equipment. The novelty of this article lies in the analytical solutions that are a combination of the Fokker–Planck–Kolmogorov equation and the equation of chemical kinetics. The novelty also consists of the simultaneous simulation and analysis of probabilistic, physical and chemical processes in one model. (2) Research literature review: Research works related to the topic of the study were analyzed. The need for a probabilistic formulation of the problem is argued, since classical statistical methods are not applicable due to the lack of statistical data. (3) Statement of the research problem: A probabilistic formulation of the problem is given taking into account the physical and chemical laws of aging and degradation. (4) Methods: The author uses methods of probability theory and mathematical statistics, methods for solving the stochastic differential equations, the methods of mathematical modeling, the methods of chemical kinetics and the methods for solving a partial differential equations. (5) Results: A mathematical model of a drifting key parameter of measuring equipment is developed. The conditional transition density of the probability distribution of the key parameter of measuring equipment is constructed using a solution to the Fokker–Planck–Kolmogorov equation. The results of the study on the developed model and the results of solving the applied problem of constructing the function of the failure rate of measuring equipment are presented. (6) Discussion: The results of comparison between the model developed in this paper and the known two-parameter models of diffusion monotonic distribution and diffusion non-monotonic distribution are discussed. The results of comparison between the model and the three-parameter diffusion probabilistic physical model developed by the author earlier are also discussed. (7) Conclusions: The developed model facilitates the construction and analysis of a wide range of metrological characteristics such as measurement errors and measurement ranges and acquisition of their statistical estimates. The developed model is used to forecast and simulate the reliability of measuring equipment in general, as well as soldered joints of integrated circuits in special equipment and machinery, which is also operated in harsh conditions and corrosive environments. [ABSTRACT FROM AUTHOR]

(1) Background: A new probabilistic physico-chemical model of the drifting key parameter of measuring equipment is proposed. The model allows for the integrated consideration of degradation processes (electrolytic corrosion, oxidation, plastic accumulation of dislocations, etc.) in nodes and elements of measuring equipment. The novelty of this article lies in the analytical solutions that are a combination of the Fokker–Planck–Kolmogorov equation and the equation of chemical kinetics. The novelty also consists of the simultaneous simulation and analysis of probabilistic, physical and chemical processes in one model. (2) Research literature review: Research works related to the topic of the study were analyzed. The need for a probabilistic formulation of the problem is argued, since classical statistical methods are not applicable due to the lack of statistical data. (3) Statement of the research problem: A probabilistic formulation of the problem is given taking into account the physical and chemical laws of aging and degradation. (4) Methods: The author uses methods of probability theory and mathematical statistics, methods for solving the stochastic differential equations, the methods of mathematical modeling, the methods of chemical kinetics and the methods for solving a partial differential equations. (5) Results: A mathematical model of a drifting key parameter of measuring equipment is developed. The conditional transition density of the probability distribution of the key parameter of measuring equipment is constructed using a solution to the Fokker–Planck–Kolmogorov equation. The results of the study on the developed model and the results of solving the applied problem of constructing the function of the failure rate of measuring equipment are presented. (6) Discussion: The results of comparison between the model developed in this paper and the known two-parameter models of diffusion monotonic distribution and diffusion non-monotonic distribution are discussed. The results of comparison between the model and the three-parameter diffusion probabilistic physical model developed by the author earlier are also discussed. (7) Conclusions: The developed model facilitates the construction and analysis of a wide range of metrological characteristics such as measurement errors and measurement ranges and acquisition of their statistical estimates. The developed model is used to forecast and simulate the reliability of measuring equipment in general, as well as soldered joints of integrated circuits in special equipment and machinery, which is also operated in harsh conditions and corrosive environments.

(1) Background: The aim of the study is to develop a set of models for managing a fleet of complex technical systems with metrological support, allowing the simulation and management at all the stages of the life cycle of the complex technical systems, as well as to simulate the functioning of large fleets of complex technical systems, including up to several hundred thousand samples; (2) Methods: The authors use methods of mathematical modeling, methods of the theory of Markov and semi-Markov processes, methods of optimization, methods of reliability theory, and methods of probability theory and mathematical statistics; (3) Results: an interconnected set of mathematical models for managing a fleet of complex technical systems with metrological support was developed and the applied software was developed; (4) Conclusions: The set of models presented in the article allows for the adequate simulation of all the stages of the life cycle of large complex technical systems fleets, including up to several hundreds of thousands of samples, to optimize the functioning processes of a fleet of complex technical systems, to form strategies for fleet development, and to assess the risks associated with false and undetected failures, as well as the risks associated with the degradation of complex technical systems. [ABSTRACT FROM AUTHOR]

Copyright of Problems of Friction & Wear is the property of National Aviation University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The focus of this study is the examination of tool wear or the causes of tool radius increase, during sawing of melamine wood panels with CNC machines. During the tests, the following materials will be used: laminated particleboard, based on the objectives of the study, for the technological sawing operation, with dimensions 2100x2800x18mm, first quality. As a cutting tool for sawing it is used the one in the shape of a disc, as in figure 4. Table 1, presents all the details of the cutting instrument, its geometry, the blade angle, the number of rotations, its material of construction etc. The examination of tool wear was measured by the direct measurement method, with the help of a measuring device called Nikon NEXIV VMR-3020 CNC Video Measuring System, with the possibility of lensing up to 270 times. While the data obtained from the measurement are presented in table no. 2, constructing an overview of the data, from the results obtained. This data was also compared by mathematical calculations, with a clear difference in consumption, between the initial radius and that after t working minutes. From all this, a mathematical model is obtained, which serves the users to choose the right instrument for the respective wood-based material, in this case carpentry boards, for the technological operation of sawing. [ABSTRACT FROM AUTHOR]

The problem to ensure the safety of objects which are in the area of blasting operations, ensuring the destruction of hard rocks, remains relevant. The article presents the results of a large-scale experiment to determine the safe conditions for conducting drilling and blasting operations near the active gas pipeline. The simplest and most reliable way to ensure the safety of the protected object from seismic impact is to reduce the intensity of the seismic wave, which is achieved by changing the parameters of drilling and blasting operations. This requires research to determine the impact of blasting operations on the parameters of seismic waves and the development of methods for measuring these parameters. The paper presents a detailed analysis of the seismic blast wave impact on the displacement of the ground and the model gas pipeline. The features of seismic monitoring during blasting operations near the active gas pipeline are shown. The seismic coefficients and attenuation coefficient of seismic waves are determined. It is proved that the readings of the seismic receivers on the surface and in the depth of the massive differ by two or more times.

This article identifies problems arising from implementing the procedure for determining the breaking forces of hexagonal gabion meshed nets according to standard number EN 10223–3:2013. The primary focus was directed towards the construction and conditions of use of an originally developed instrument that allows gabion meshed net samples to be mounted in the grips of a conventional strength testing machine. This paper presents a device prototype adapted to the conditions of mounting samples (for strength testing) in the jaws of a Zwick Z100 strength testing machine. An instrument designed for the purpose of scientific research, expert opinions and direct determination of the mechanical properties of hexagonal gabion meshed nets compliant with all the requirements of the aforementioned standard. ● Measurement problems of load bearing capacity of hexagonal gabion meshed nets. ● Reference to the procedure for testing nets according to the standard EN 10223-3:2013. ● A prototype of installed fixture in a conventional strength testing machine. ● Method of installation of gabion meshed net samples. ● A universal instrument that facilitates measure strength of hexagonal meshed nets. [ABSTRACT FROM AUTHOR]

This paper is about condition based maintenance and technical diagnostic on specifically object-cylinder units of two stroke low speed diesel engine MAN B&W 8K80MC-C. It describes: the way of controlling direct parameters (pressure and temperature) taken from the engine, measuring the pressure in engine cylinders via electronic device "PREMET" and visual control of cylinder liners and pistons. Analyzing the data we got clear conclusion about needs of preventive action or possibility of extension of exploitation without maintenance for certain period. Practice confirms that it is possible to extend the period between two overhauls while maintaining engine performance within the limits prescribed by the manufacturer and the values of the parameters obtained on the test drive, as well as reduce maintenance costs.

(1) Background: The aim of the study is to develop a set of models for managing a fleet of complex technical systems with metrological support, allowing the simulation and management at all the stages of the life cycle of the complex technical systems, as well as to simulate the functioning of large fleets of complex technical systems, including up to several hundred thousand samples; (2) Methods: The authors use methods of mathematical modeling, methods of the theory of Markov and semi-Markov processes, methods of optimization, methods of reliability theory, and methods of probability theory and mathematical statistics; (3) Results: an interconnected set of mathematical models for managing a fleet of complex technical systems with metrological support was developed and the applied software was developed; (4) Conclusions: The set of models presented in the article allows for the adequate simulation of all the stages of the life cycle of large complex technical systems fleets, including up to several hundreds of thousands of samples, to optimize the functioning processes of a fleet of complex technical systems, to form strategies for fleet development, and to assess the risks associated with false and undetected failures, as well as the risks associated with the degradation of complex technical systems.

The bed shear stress under the action of waves is one of the important essential parameters to estimate the incipient motion and transport of offshore sediment, and its bottom friction effect will also have an impact on the offshore hydrodynamic environment. Due to the difficulty in field observation, the understanding of the wave boundary layer and the bed shear stress under the action of waves is mainly based on indoor experimental observation. This paper reviews the relevant theoretical models and experimental measurement research at home and abroad, sorts the advantages and disadvantages of various research methods and measurement techniques, as well as the application conditions, collates a lot of experimental data from 1970s to now, generalizes and analyzes the existing research results, including the impact of wave nonlinearity, wave breaking and other factors on the bed shear stress, summarizes the limitations of the existing research, and puts forward the future research focuses. Super- large water flume is an important facility to break through the bottleneck in the theoretical study of the layer of wave boundary in the future. The development of high- adaptability underwater two-dimensional shear stress sensor is the key to making a breakthrough in the study of bed shear stress under complex dynamic conditions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Universal Excellence (JUE) / Revija za Univerzalno Odličnost (RUO) is the property of Fakulteta za Organizacijske Studije v Novem mestu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper describes selected problems concerning the character of management of control and measuring equipment in small and medium enterprises. There are discussed the oversight process over control and measuring equipment as well as there are itemized duties of people managing manufacturing process and worker who controls measuring equipment. There are briefly discussed selected problems concerning the calibration of control and measuring equipment as well as preparing of a workplace for its control. Conclusions are drawn concerning particular activities significantly influencing the management of control and measuring equipment.

The problem of improving the quality of forecasting the cost of measuring equipment is considered. The main methods and models for forecasting the cost of measuring equipment, as well as the main factors that determine the cost are described. A method for calculating the cost of promising measuring equipment, which allows taking into account its technical specifications, has been developed. Methods for calculating the nonlinear dependence of the cost of measuring equipment on its technical specifications are suggested. As an example, additive and multiplicative models of the cost of generators of high-frequency signals and spectrum analyzers as functions of the technical specifications of these devices are considered. [ABSTRACT FROM AUTHOR]

The subject of research in the article are methods and means of measurement and testing. The goal of the work is to analyze the metrological requirements of the ISO/IEC 17025:2017 standard for equipment and methods used to conduct tests in laboratories to ensure control of the metrological system processes, and to provide information on the practical application of the requirements of this standard, taking into account the provisions of other international standards. The following tasks are solved in the article: analysis of the position of international documents containing the requirements to the equipment and test methods for measurement in order to determine their practical implementation; analysis of ISO/IEC 17025:2017 on metrological requirements and proposed ways of implementation of these requirements. The following methods are used - analysis method. The following results have been obtained: the analysis of international requirements to the equipment, including measuring, testing (measurement) and standardization of these requirements has been carried out to implement the provisions of ISO/IEC 17025:2017. An important factor in the implementation of the standard in Ukraine is that currently there are no national standards that would regulate the general requirements for the use of measuring equipment and assess the accuracy of measurement results. This standard provides general approaches to the use of equipment and accuracy characteristics of the results obtained by appropriate methods. Fulfillment of the requirements of the methodology makes it possible to obtain a reliable result with the required accuracy. Conclusions: on the basis of the carried out analysis it is established that ISO/IEC 17025:2017 became a new perspective step towards application of metrological requirements to means and methods of testing and measurements defined by various other international documents in the field of metrology; the standard is a fundamental, in fact, reference book for metrologists on organization of work on assurance of reliability of measurement results and tests at the enterprise; assurance of conformity to the requirements of the international standard provides customers with confidence in the results of measurements.

In agricultural production, pests and diseases of agricultural crops, as well as weed plants, cause significant losses in the yield and quality of agricultural products. One of the most effective ways of fighting is the use of a wide range of chemicals called pesticides. In accordance with the EU Directives 2009/128/EC and 2006/42/EC underlying the standard EN 13790, the Plant Protection Administration of the Ministry of Agriculture and the Environment of the Republic of Serbia has established a framework for the control of sprayers and mist blowers. Maintaining sprayers for pesticide application in a good state of repair and proper working order reduces their harmful effects on human health and the environment. The nozzle is one of the most important parts of plant protection machines, responsible for the following major functions: delivery of a given amount of liquid in a unit of time, dispersion of the liquid by making droplets of different sizes and forming a stream of a particular shape. Testing of the working safety of sprayers and nozzles was carried out in accordance with the European Standard EN 13790 which specifies the methods and equipment for inspection. The flow rate of nozzles was measured by an S001 nozzle tester (AAMS-Salvarani, Belgium). The measuring equipment used for testing the pesticide application device can accurately determine any deviation and irregularity in the application.

The aim of this study is to verify whether a Raspberry Pi 3 B+ can be utilized as a low-cost device for controlling a tensile-testing device used for material research purposes. A list of requirements based on already-available hardware was drawn up, which the new control system had to fulfil. To connect all the necessary equipment, a connection board was constructed, and some additional hardware was acquired for the system to be able to perform all the necessary tasks. The whole controlling system was also put in a small enclosure to make it portable. The control-system software was written in C++ using the Pigpio library. The developed system was then tested, and the results were compared to a commercially available Instron 8802 device. A comparison of the results shows that the upgraded equipment can produce comparable results to commercially available devices and is sufficiently accurate to be applied for research purposes for the characterization of soft tissues and other materials. [ABSTRACT FROM AUTHOR]

The aim of this work was to develop and evaluate a color measurement prototype in fresh vegetables as an economic alternative to equipment and commercial techniques. The DHT11 temperature and TCS230-3200 color sensors were used connected to a data acquisition card (Arduino Nano). The information transfer to a computer was established with the PXL-DAQ and Microsoft Excel® 2013 software, and the measurements were recorded in RGB color model for its conversion to CIE L*a*b* system. Comparison tests of measurements were carried out on PANTONE color chart with the prototype and a Konica Minolta CR-400 colorimeter, determining the average error between measurements. An average error of 15,57% and 27,45% was found in the measurements registered by the color prototype and the colorimeter, respectively, which showed that the use of prototype is an appropriate alternative technique for measuring color in fresh vegetables. [ABSTRACT FROM AUTHOR]

The article is dedicated to the analysis of areas where terahertz radiation is applicable with the hwlp of a patent papers review, as well as to obtaining knowledge about the invention activity changes in this area over the past 35 years.Orbit patent databases’ capabilities were used to complete this analysis. Data search was conducted by keywords “terahertz” or “THz.” The searches were neither limited by submission dates, by priorities, nor by the country. A comprehensive analysis will allow to determine a more than 7389 patent-analog families’ aplications submitted in the period between 1980 and 2017 years. Statistical processing of obtained documents has been completed with the assistance of program software, indicated in the database. It was revealed that terahertz technologies have significant prospects to be applied in various areas; a fact, that is confirmed by an identified range of fields, where electromagnetic radiation of terahertz spectrum is applicable and is constantly growing. The dynamics of patenting is characterized by annual stable positive growth in the number of applications for inventions in the researched area. The highest number of inventions was identified in the field of instrumentation technologies, optics, telecommunications, semiconductor technologies, and medicine. Additionally, there was analyzed the state of patenting over the course of last five years. Examples of inventions were given. There were identified leading countries and companies in the researched area.

The computation of energy dissipation in mechanical protective systems and the corresponding determination of their safe use in mine shafts, requires a precise description of their bending and elongation, for instance, in conditions of dynamic, transverse loading induced by the falling of mass. The task aimed to apply a fast parallactic rangefinder and then to mount it on a test stand, which is an original development of the Central Mining Institute's Laboratory of Rope Testing in Katowice. In the solution presented in this paper, the measuring method and equipment in which the parallactic laser rangefinder, provided with a fast converter and recording system, ensures non-contact measurement of elongation, deflection or deformation of the sample (construction) during impact loading. The structure of the unit, and metrological parameters are also presented. Additionally, the method of calibration and examples of the application in the impact tests of steel wire ropes are presented. The measurement data obtained will provide a basis for analysis, the prediction of the energy of events and for applying the necessary means to maintain explosion-proofness in the case of destructive damage to mechanical elements in the mine atmosphere. What makes these measurements novel is the application of a fast and accurate laser rangefinder to the non-contact measurement of crucial impact parameters of dynamic events that result in the destruction of the sample. In addition, the method introduces a laser scanning vibrometer with the aim of evaluating the parameters of the samples before and after destruction.

This article describes the details of the method designed to determine parameters of vehicle's internal combustion engine with compression ignition (CI) during road tests. The method requires simultaneous measurements for the crankshaft rotation frequency, fuel pressure in the injector, pressure in the combustion chamber, air pressure and temperature in the intake system. More, this method utilizes possibilities of the GPS navigation - all the received data is being synchronized with navigation data and saved to the database. Fuel consumption was calculated using the original method based on processing the pressure data from inside the cylinder alongside with the fuel injection parameters, previously received from the injection system and engine tests in the laboratory. Obtained characteristics allow to perform detailed analysis for the engine's single work cycle in the transient processes, which are the biggest part of engine's common work conditions. Measurements results received with help of the created experimental gear were used to determine CI engine parameters. Those parameters may help in simulation of the engine work inside the vehicle, and could be used in engine parameters optimization tasks. [ABSTRACT FROM AUTHOR]

A configuration of the multichannel system for diagnostics of radiative processes in various regions of the discharge appearing in semiconductors in response to high-voltage pulses is considered. The system allows real-time recording of spectra, dynamics, and energy of radiation in nine emitting object zones 200-400 μm in diameter. The recording equipment is connected to objects under study by fiber-optic cables (FOCs). The system temporal resolution can be varied from 40 to 250 ps depending on the FOC diameter. An example of the simultaneous study of spatiotemporal characteristics of the streamer discharge at seven points of a CdSxSe1−x semiconductor wafer is given. [ABSTRACT FROM AUTHOR]

Mobile measuring equipment adapted for measurements of low-frequency noise of vacuum tubes with a broad range of impedance characteristics has been developed. Control software making it possible to measure and process the obtained results in automatic mode has been created. The capability of determining the diagnostic parameters of thermionic cathodes of vacuum tubes is shown. [ABSTRACT FROM AUTHOR]

Copyright of E-Pedagogium is the property of Palacky University in Olomouc and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper describes a proposal to improve the educational process of students of the Military Academy to support the maintenance process of the Serbian Army aircraft based on the introduction of objects in flight test aircraft. It is particularly emphasized the importance of establishing airline laboratories with basic characteristics of the test-measuring equipment that is necessary to integrate the aircraft to perform a practical test of an aircraft in flight. The formation of aircraft laboratories would form a very strong didactic tool, which provides for optimal synthesis of theory and practice. This concept of improving the educational process would be substantially affected the awareness of the necessity of working together and put together all the research capacity of scientific institutions in the Ministry of Defence of the Republic of Serbia.