Вимірювальна техніка та метрологія. – 2020. – Випуск 81, №1

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Measuring Equipment and Metrology : scientific journal. – Lviv : Lviv Politechnic Publishing House, 2020. – Volume 81, № 1. – 56 р.

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Start date: 2020End date: 2020

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    Information of editorial board for authors of manuscripts
    (Видавництво Львівської політехніки, 2020-02-24)
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    Soft (perceptual) metrology: dissemination of information-measuring technologies in the area “Measuring the impossible”.
    (Видавництво Львівської політехніки, 2020-02-24) Motalo, Vasyl; Chereshnevska, Anzhelika; Savitska, Yuliia; Lviv Polytechnic National University
    The article focuses on the main problems of the development of the soft (perceptual) metrology as one of the new progressive areas of modern metrology that has appeared as a result of the dissemination of the information measuring technologies into the field of knowledge of non-physical phenomena and processes. An overview and analysis of well-known works on the topic of soft metrology are conducted. The areas of soft metrology research have been considered and analyzed, in particular, the investigation of the correlation between human, subjective responses to stimuli and physical, objective measurements. The question of the methodology of carrying out sensometrical measurements, that is, measurements of quantities characterizing the human sensations and responses to stimuli is considered. The main tasks of the research in the field of soft metrology for the implementation of its concept in practical applications, in particular in robotics have been established.
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    Challenges of temperature measurement during the friction stir welding process
    (Видавництво Львівської політехніки, 2020-02-24) Augustin, Silke; Fröhlich, Thomas; Krapf, Gunter; Bergmann, Jean-Pierre; Grätzel, Michael; Gerken, Jan Ansgar; Schmidt, Kiril; Technical University
    The exact determination of the process zone temperature can be considered as an increasingly important role in the control and monitoring of the friction stir welding process (FSW). At present, temperature measurement is carried out with the aid of a temperature sensor integrated into the tool (usually thermocouples). Since these cannot be attached directly to the joining area, heat dissipation within the tool and to the environment cause measurement deviations as well as a time delay in the temperature measurement. The article describes a process and the challenges that arise in this process, how a direct temperature measurement during the process can be achieved by exploiting the thermoelectric effect between tool and workpiece, without changing the tool by introducing additional temperature sensors.
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    Micro-service support by module architecture application of the service platform for OSGI Java additions
    (Видавництво Львівської політехніки, 2020-02-24) Mamro, Oleksandr; Lagun, Andrii; Lviv Polytechnic National University
    This article analyzes the problems of creating and maintaining the micro-service-oriented architecture. The solution of the OSGI modular architecture and its alternatives was also considered, as well as the strength and weakness, were identified. The practical part is to create an OSGI system for IoT (wireless network access), which uses a sensor system and a data processing system, with a centralized modular system for processing input data from different devices. The modules are broken down into data processing functionality. The complexity of refactoring micro-service architecture using OSGI modules was also investigated.
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    Neurocontrolled object parameters adjustment by Ackermann’s formula usage
    (Видавництво Львівської політехніки, 2020-02-24) Nakonechnyi, Markiyan; Ivakhiv, Orest; Viter, Oleksandr; Nakonechnyi, Yuriy; Lviv Polytechnic National University
    Synthesis methods of controllers based on the use of frequency characteristics or root hodographs are considered classic or traditional. Frequency methods are available in practical applications, and most control systems are designed based on various modifications to these methods. A distinctive feature of these methods is the so-called robustness, which means that the characteristics of a closed system are insensitive to the minor errors of the model of the real system. This feature is significant because of the complexity of constructing an accurate model of the real system, as well as the fact that many systems are inherent in all kinds of nonlinearities, which complicate their analysis and synthesis. In recent years, many attempts have been made to develop new methods of synthesis, commonly referred to as modern control theory. One synthesis method is like the root hodograph method, which allows positioning the poles of the closed-loop transfer function at predetermined points. In the article on the basis of information about the desired transient characteristic of the reference, which is obtained on the basis of a dynamic neural network, using the Ackerman formula, a procedure for calculating the coefficient matrix, whose introduction in the structure of the object model provides the specified dynamics of the process. On the base of the reference mathematical model is created the architecture of the corresponding dynamic neural network. During training, there is the target function as a numerical sequence that corresponds to the desired transient characteristic of the system, and the input signal is given in the form of a numerical sequence that reproduces jump function. Using the values of the weight coefficients obtained in the course of learning the neural network, the coefficients of the mathematical model of the reference and the roots of its characteristic equation are calculated, with the following calculation using the Ackerman formula of the coefficients of the matrix, whose values are entered into the structure of the model ensuring the specified dynamics of the process in it.
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    Measuring logarithmic signal converter for magnetic tracking systems
    (Видавництво Львівської політехніки, 2020-02-24) Holyaka, Roman; Marusenkova, Tetyana; Fedasyuk, Dmytro; Lviv Polytechnic National University
    The work deals with the problem of signal conversion in magnetic tracking systems. Magnetic tracking systems are a novel development trend of navigation sensors within the concepts of the Internet of Things and virtual and augmented reality. In contrast to optical tracking systems, magnetic ones do not suffer from occlusions. In comparison with tracking systems built upon inertial sensors, they are not susceptible to bias drift and provide better accuracy. Magnetic tracking technology is based on calculating the position of objects upon the dynamic measurement of the reference magnetic field vectors. The reference magnetic fields are formed by arrays of actuator coils in the low-frequency electromagnetic radiation spectrum. Those who implement a magnetic tracking system have to ensure noise-immune measurements of signals coming from sensor coils in a wide dynamic measurement range. The range changes from microvolts for distances of several meters in couples “actuator-sensor” to hundreds of millivolts in the case if the distances in “actuator-sensor” couples reduce to several centimeters. Thus, one requires signal converters able to provide highly noise-immune measurements in a dynamic measurement range covering six orders of magnitude. The work presents the results of development, simulation, and investigation into a signal converter for magnetic tracking systems, whose novelty consists in combining the methods of logarithmic amplification and synchronous demodulation of the output signals of the sensor coils. The main nodes of the developed signal converter are a control unit, a logarithmic amplifier, a synchronous demodulator, a low-pass filter, an actuator driver and an analog-to-digital converter. Voltage logarithm compression has been performed upon volt-ampere characteristics of semiconductor p-n junctions. The synchronous demodulator provides a high level of selection of the useful signal out of electromagnetic noise. The results presented in this paper are part of our complex research work related to the development of the Magnetic Tracking System Integrated Development Environment (MTS-IDE). The latter is being developed by a team of scholars within different projects and is aimed at enhancing the efficacy of parametric optimization and synthesizing firmware of embedded systems implementing integrated magnetic tracking sensors. Simulation and experiments have shown that the dynamic range of noise-immune signal measurement using the developed converter covers six orders of magnitude, from 1E-6 V to 1 V. Investigation into functionality were conducted by oscillograph methods. The characteristics of the proposed solution were measured by the above-mentioned MTS-IDE. The obtained results are of key importance for further improvement of magnetic tracking systems, particularly, for their noise-immune measurement volume expansion.
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    Quality structuring of medical services by decomposition of quality function
    (Видавництво Львівської політехніки, 2020-02-24) Mykyichuk, Mykola; Chaban, Olesia; Lviv Polytechnic National University; Lviv National Medical University named after Danylo Halytsky
    Quality medical care is an important indicator of the economic development of a country. Today, improving the quality of health care services is a priority for both health care institutions and the state as a whole. The development of methods and tools for continuous improvement of the quality of medical services promotes regulation, the perfection of those services, ensures the effective working of all the components together and the consistency and continuity of their provision, as well as help the staff to determine how to achieve the optimal level of care. The implementation of modern methods of ensuring the quality of products and services in medical practice is aimed at increasing patient satisfaction and receiving adequate and professional medical care, in accordance with the principles of Good Clinical Practice. Therefore, it is important to summarize and systematize the requirements for healthcare delivery processes. A key element of the quality management model of care is a process analysis, which involves the identification and design of processes along with their continual improvement. At the same time, the result of management is based on a cycle of actions aimed at minimizing the frequency of deviations in key processes, which guarantees the achievement of the best potential scientifically verified results. There are several groups of processes in a medical institution: treatment, diagnostics, supply, etc. Defining the function of the quality of medical services and their decomposition will allow for optimizing the work of medical institutions and encourage efficiency and competitiveness in innovative development. The article presents the scheme of optimization of medical services by decomposition of their function of quality. A graphic model of decomposition of the function of the quality of health services is proposed based on the model of relations which will formalize the requirements for the processes of providing medical services in a medical institution. This will help to provide healthcare services gradually and minimize the loss of quality of the provided medical services.
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    Investigation of thermometric material Ti1-xScxCoSb modeling of characteristics
    (Видавництво Львівської політехніки, 2020-02-24) Krayovskyy, Volodymyr; Rokomanyuk, Mariya; Romaka, Volodymyr; Horpenyuk, Andriy; Stadnyk, Yuriy; Romaka, Lyubov; Horyn, Andriy; Lviv Polytechnic National University; Ivan Franko National University of Lviv
    The second part of the complex research of Ti1-xScxCoSb thermometric material for the sensitive elements of thermoelectric and electro resistant thermal converters is presented. Simulation of thermodynamic, electrotechnical, energetic and structural characteristics of Ti1-xScxCoSb semiconductor thermometric material for various options of atoms placement is performed. It is determined that under the orderly variant of the crystal structure Ti1-xScxCoSb the characteristic simulation results do not correspond to the experimental research results of temperature and concentration dependences of the resistivity, thermoEMF coefficient of the Fermi εF level behavior character, etc. Thus, for the ordered structure of Ti1-xScxCoSb, the simulation showed that the substitution in the crystallographic position 4a of the TiCoSb compound of atoms Ti (3d24s2) at Sc (3d14s2) generates structural defects of the acceptor nature since the Sc atom has fewer 3 d-electrons. Adding to the TiCoSb the smallest in the experiment concentration of Sc atoms by replacing the Ti atoms radically changes the behavior of the resistivity ρ and the coefficient of thermo-EMF α Ti0.995Sc0.005CoSb. In the 80–350 K temperature range, the resistivity value ρ increases with temperature increasing, and the conductivity of Ti0.995Sc0.005CoSb is metallic. It means that the addition of the smallest in the experiment concentration of atoms Sc (x=0.005) which should generate acceptors changed the position of the Fermi level εF in a way that could only cause the appearance of donors in the semiconductor. Thus, if in TiCoSb the Fermi level εF laid in the restricted area, then the metallization of the conductivity Ti0.995Sc0.005CoSb indicates that it not only approached the conduction zone but also crossed its leakage level, and electrons remain the main carriers of electricity. This is indicated by the negative values of the thermo-EMF coefficient α Ti0.995Sc0.005CoSb, which is only possible if donors of unknown nature are generated. The metallization of the conductivity Ti0.995Sc0.005CoSb also does not match the results of the electronic structure simulation for the ordered structure variant. After all, the simulation demonstrates that at the smallest concentration of the Sc acceptor impurity, the Fermi level εF drifts from the conduction zone εC to the middle of the restricted zone εg. Therefore, in the high-temperature area of dependence ln(ρ(1/T)), there must be an activation area associated with the thermal emission of electrons from the Fermi level εF into the conduction zone εC, and the value of the electron activation energy ε1ρ should be greater than in the case of TiCoSb. To clarify the crystalline and electronic structure of the TiCoSb compound, electronic state density distribution (DOS) simulations were performed for various options of occupying crystallographic positions by atoms, as well as occupying by atoms of tetrahedral voids of structure that make up ~24 % of the unit cell volume. It is shown that structural defects of the donor and acceptor nature are present in the TiCoSb base compound as a result of the location in the tetrahedral voids of the structure of additional Co * atoms and the presence of vacancies in the crystallographic position of 4a of the Ti atoms. Introduction to TiCoSb compound of impurity Sc atoms by substitution at position 4a of Ti atoms generates structural defects of acceptor nature, and the ratio of Ti1-xScxCoSb in the concentrations of available defects of donor and acceptor nature determines the location of the Fermi level εF and mechanisms of conductivity. The obtained results allow us to predictably simulate and obtain thermometric materials Ti1- xScxCoSb for the sensitive elements of thermotransducers.
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    Content
    (Видавництво Львівської політехніки, 2020-02-24)
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    Титульний аркуш до "Measuring equipment and metrology"
    (Видавництво Львівської політехніки, 2020-02-24)