Andrzej Juś

Methods of Determining Information Support of Web Community User Personal Data Verification System

This article considers the concept of information support of web community member personal data verification system. It has been established that information support of verification system depends on the following parameters: profile filling level, profile data and content actuality level, administrative authority, web user activity level and level of compliance with virtual community rules. The paper also analyzes an actual task of developing methods for determining information support of web community member personal data verification system. The level of information support of web community member personal data verification system allows evaluating the effectiveness of verification system in web-community management. It is concluded that the higher is the level of information support of web community member data verification system, the better is the community management performance, and therefore, web community operation.

Test Stand for Temperature Characteristics of Ultra-Precise Resistors

Paper presents the test stand, measurement methodology and exemplary results of measurements of thermal characteristics of ultra-precise resistors. Precise resistors are commonly used, as current-voltage converters or in precise current sources. Electric circuits are supposed to work in wide range of temperatures, which can change the resistance value, and thus be a source of unacceptable measurement error. Therefore it is important for designers and constructors to select the most temperature-stable resistors. The presented test stand is a reliable source of data about resistors temperature coefficients, with accuracy of 0.05 ppm/oC.

Test Stand for Matteucci Effect Measurements

In this paper test stand consisting of Joule annealing station, and magnetic field measurement stand for Matteucci effect investigation is described. The system allows for annealing of amorphous wire samples while applying torsion (twisting of the wire), and measuring the ME voltage response to alternating magnetic field applied to sample in chosen directions. This paper presents preliminary results of the measurements which will help modelling of ME in computer simulations.

Assessment of Temperature Coefficient of Extremely Stable Resistors for Industrial Applications

The article presents the results of tests of the temperature characteristics of resistors with very low TCR and the lowest price in their class. The study was conducted in terms of their use as reference in the processing current voltage system in the magnetomechanic part of the analytical scale. However, they are also widely used in applications where the constant value of resistance in the whole measuring range is critical. The results not only confirm the usefulness of the tested resistors, but can also ensure significant cost reduction in many applications.

Automatic System for Identification of Temperature Parameters of Resistors Based on Self-heating Phenomena

Paper presents new way of identification of temperature parameters of precise resistors. Presented method allows removing heating system and temperature measurement system from the test stand, and is suitable for resistors with extremely low TCR. This approach is based on observation of resistance variation caused by the flow of constant current of known value. Presented method has high measurement accuracy. It is also suitable for process automation, and allows for the simplification of the test stand and shortening of the time required to perform the resistor TCR measurement.

Assessment of Graphene Coatings Influence on Tribological Properties of Surfaces

This paper presents results of experiments carried out to determine influence of graphene coating on tribological properties of surfaces of friction pairs. Within these experiments series of 24 h tribological tests of sliding friction between examined surfaces on specially designed measuring stand were conducted. Subject of study in these tests were electrolytic copper plated steel samples, additionally covered with graphene and, as a reference, identically prepared samples without the graphene layer. As a result of these experiments characteristics of coefficient of friction and temperature between surfaces, as well as changes in mass and roughness before and after tests were obtained. Based on these results improvement of tribological properties of sliding surfaces was shown.

Research of Metal Film Resistor’s Temperature Stability According to Their Nominal Wattage

Paper presents the results of tests of temperature characteristics of resistors according to their nominal wattage. Object of the study are cheap, popular metal film resistors of the same type and producer in the wattage range 0.4–2 W. There is a possibility of selecting some of those resistors and using them as a current-voltage converters. In such application resistors are supposed to work in a wide range of temperatures, which can significantly change their values. So the influence of nominal wattage on temperature stability of resistors was checked. The study was conducted on high resolution test stand.

Test Stand for Measuring Magnetostriction Phenomena Under External Mechanical Stress with Foil Strain Gauges

In this paper developed test stand for measuring magnetostriction deformation under external mechanical stress is presented. Magnetostriction phenomena is usually undesired, but there are applications which uses this phenomena in purpose for example to generate acoustic wave. In both cases complex approach and knowledge of magnetostriction factor λ in different material tensions are important. Usage of precision strain gauge, 24-bit analog to digital converter and digital signal processing allowed to achieve high resolution and accurate measurements of magnetostriction. All this also gives opportunity to measure small values of magnetostriction factors which are in materials like construction steels.

Resistance of MAX 6325 Reference Voltage Source on Operating Temperature Variation

The article presents the problem of the Zener diode based reference voltage sources resistance to changes in operating temperature. The test stand, measurement methodology and results are presented. Reference voltage sources are crucial elements of analog-to-digital systems. They set the standard to which the measured voltage is compared to. Therefore, the stability of their work is critical for many areas of precision metrology.

Resistance of MAX 6325 Reference Voltage Source on Supply Voltage Variation

The article presents the problem of reference voltage sources based on Zener diode resistance to changes in power supply. The test stand, measurement methodology and results are presented. Reference voltage sources are crucial elements of analog-to-digital systems. They set the standard to which the measured voltage is compared to. Therefore, the stability of their work is critical for many areas of precision metrology.