No. 5

Experience in metrological supervision, development and operation of automatic weight and dimension control

Automatic weight and dimension control of heavy-duty vehicles parameters has been used in Russia for a number of years to ensure the safety of roads and their infrastructure (bridges, tunnels, overpasses, etc.). Since the fines for «overweight» and «oversized» for carriers are noticeably large, and the number of automatic weight and dimension control posts (AWDC) on the country's roads is already in the hundreds, their correct operation and maintenance in good condition imposes great responsibility on manufacturers and owners. The article examines the experience of development, operation and metrological supervision of AWDC, accumulated by «Tenso-M» Weight Measuring Company which is one of the main manufacturers of such measuring instruments, and also suggests ways to improve the processes of monitoring their metrological characteristics.

Keywords: AWDC, error, weight and size control, metrological supervision, variable force standard, control of metrological characteristics.

Issues of practical implementation of the Strategy for Ensuring the Uniformity of Measurements in the Russian Federation

As part of the implementation of the Strategy to Ensure the Uniformity of Measurements in the Russian Federation until 2025, along with many tasks that need to be solved, the task of developing and implementing methods for remote calibration and verification of SI was also denoted. The very approach of using remote access in the organization of SI verification, for all its potential attractiveness, breaks many established stereotypes associated with the methodology of SI verification. The analysis carried out in connection with the expiration of the time allotted for the implementation of the Strategy shows that the mentioned task has been successfully solved within a particular SI park. However, generalization (dissemination of this experience) to other SI parks has not taken place and requires additional efforts by the regulator aimed at developing standards for the integration of SI operated in the field of state regulation of ensuring the uniformity of measurements with automation tools used for the organization of verification.

Keywords: verification, calibration, measuring instruments (SI), remote access, mass measurement, automation tools, strategy, ensuring the uniformity of measurements.

On methods of verification of crane scales using standards of the unit of force

The existing methods for verifying crane scales using 1st class force-reproducing machines, in accordance with the State Verification Scheme for force measurement instruments, have been analyzed. The shortcomings of these methods, as well as the challenges arising from the requirements of GOST OIML R 76-1-2011 during crane scale verification, have been identified. Using the example of crane scale verification with reference force-reproducing machines, the components of measurement error associated with additional loadings, attaining the specified load, and zero setting have been examined. Solutions to the mentioned issues are proposed, including additional regulation of the technical and metrological characteristics of force-reproducing machines, the development of new crane scale verification methodologies, and amendments to the State Verification Schemes for mass and force measurement instruments. The relevance of updating existing national standards and methodological guidelines, as well as developing new ones, has been emphasized.

Keywords: crane scales, reference standard, verification, mass measurements, force-reproducing machine, weights.

Non-destructive testing and determination of the physical properties of solid materials using thermosonic analysis

A method of non-destructive testing for the physical parameters of solid materials is proposed. This method allows for the measurement of temperatures, heat flow, and the determination of thermophysical and acoustic properties using the thermoacoustic analogy. The article presents a mathematical study, during which the parameters, dependencies and criteria characteristic of the propagation of temperature and sound waves in solid materials were determined. The results of the mathematical experiment were confirmed experimentally on a fluoroplast sample. Based on experimental data on temperature and heat flow, important physical properties of the material were calculated, such as thermal conductivity, volumetric heat capacity, thermal conductivity, surface velocity of the temperature wave, as well as the acoustic velocity of sound in the material. Experimental verification of the developed method and the system that implements it has shown a significant improvement in accuracy in determining the properties of the material – by more than 5 %.

Keywords: non-destructive testing, thermosonic analogy, thermosonic and physical properties, temperature waves, building materials.

Comparative analysis of sorption-frequency, electrolytic, and psychrometric methods for gas humidity measurement

A comparative analysis of three gas humidity measurement methods is presented: sorption-frequency, electrolytic (P2O5-based), and aspiration psychrometric. Based on the long-term experience of NPP OKBA LLC in the development and application of humidity meters, the physical principles, metrological characteristics (accuracy, sensitivity, response time), advantages, and limitations of each method are examined in detail. It is shown that the sorption-frequency method provides the best response time and high accuracy over a wide measurement range but is sensitive to sample contamination. The electrolytic method demonstrates high sensitivity for measuring trace moisture concentrations. The aspiration psychrometric method is the most cost-effective solution but has higher inertia and requires strict adherence to operating conditions. Application specifics of the methods in various industries are discussed, where humidity control is critical for product quality, process efficiency, and equipment safety.

Keywords: gas humidity measurement, hygrometer, humidity analyzer, dew point, sorption-frequency method, electrolytic method, psychrometric method, P2O5-sensor, analytical control.

Design of digital logic circuits using memristors

Digital logic circuits (4-to-1 multiplexer, full adder, 2 x 2 multiplier) have been developed based on a combination of memristors and nMOS transistors. Compared to other memristor-based combinational logic circuits and classical CMOS implementations, a significant reduction in the number of transistors has been achieved while maintaining full functionality. Simulation confirmed the complete compliance of the circuit operation with their truth tables. The implemented structures demonstrate increased compactness and potential for energy-efficient digital systems.

Keywords: memristor, combinational logic, multiplexer, adder, multiplier, LTspice.

Methods and hardware for protecting the intellectual property of integrated circuits in fabless manufacturing

The paper is devoted to the implementation of methods and hardware to protect the intellectual property of integrated circuits in fabless manufacturing. It is proposed to use a route for manufacturing microcircuits, in which they are inoperable after leaving the factory and must be activated in a way that is known only to the developer company. A general scheme for activating the resources of the microcircuit is proposed. A chip identifier encryption system has been developed based on the metastability property of a trigger of an arbiter physical unclonable function.

Keywords: integrated circuit, contract manufacturing, intellectual property protection, chip resource activation, chip identifier, physically unclonable function, metastability.

Development of automatic control system of the step-down voltage converter

Development of automatic control system for DC/DC step-down voltage converter is considered. The control is organized by methods of modal synthesis and fuzzy regulation. The mathematical model is obtained in MATLAB/Simulink visual modeling environment.

Keywords: automatic control system, regulator, fuzzy logic, modal synthesis, MATLAB, Simulink, step-down voltage converter.