This article describes the interlaboratory comparison (ILC) of meteorological and hydrological calibration laboratories in the field of temperature, humidity and pressure. The ILC was organized by the World Meteorological Organization (WMO) Regional Instrument Centre (RIC) at the Slovenian Environment Agency and University of Ljubljana, Faculty of Electrical Engineering, Laboratory of Metrology and Quality as an accredited interlaboratory comparison (proficiency testing) provider according to the ISO/IEC 17043:2010 standard. The ILC was organized in the target area of WMO Regional Association VI (Europe). The protocol and procedure for ILC were developed within European Metrology Research Project (EMRP) MetoMet2 by UL-FE. The participants used their standardized procedures for calibration. Because of the large number of participating laboratories (18) from 17 countries, the ILC was organized in two loops, which were linked via four linking laboratories. The article presents the data processing, the linkage procedure, and the main results for all three categories (temperature, humidity, and pressure).
COBISS.SI-ID: 12364884
Industrial use of Radiation Thermometers (RTs) is becoming increasingly common due to the perceived advantages and wide market availability. Blackbody Cavity Radiation Sources (BCRSs) are typically used for calibration of these instruments, and these cavities are oriented horizontally in most cases. For BCRSs based in thermal baths, this necessitates the use of custom-built baths with side openings. This paper presents a unique design of vertical bath-based BCRS that may be immersed in conventional calibration baths without modifications to the baths. The method, results, and analysis of an international comparison comparing this vertical BCRS, standard horizontal BCRSs, and a previous iteration of the vertical design of BCRS are also presented.
COBISS.SI-ID: 11773012
The paper describes design and analysis of a non-contact heart rate variability measuring device based on ultrasound transducers operating at two frequencies simultaneously. Laboratory results and clinical evaluations of device are presented using healthy subjects and patients with known heart conditions.
COBISS.SI-ID: 11961684
A novel, non-contact, optical type of surface moisture sensor was designed and investigated. It is based on absorption of NIR light absorption from laser source. Two laser sources are used, one with water-absorbing wavelength and the other which is much less affected by water and two InGaAs photo diodes. The sensor’s response was measured by a precision embedded data acquisition system NI CompactRIO and evaluated using a moisture analyser.
COBISS.SI-ID: 10861652
This paper describes a procedure for metrological evaluation of skin conductance measurement. Three commercial devices for measuring skin conductance were calibrated by comparison with a precision digital ohmmeter used as a reference. Combined measurement uncertainty of skin conductance meters was calculated by means of uncertainty of reference instrument and uncertainties due to measurement repeatability, reproducibility, resolution and environmental condition. Measurement uncertainty analysis showed that contributions due to resolution and sensitivity of the measuring device, usually obtained from specifications, are negligible when compared to uncertainty of measuring method.
COBISS.SI-ID: 9940052
This paper proposes a method to estimate power quantities based on IEEE 1459-2010 using measurement window with length as close as possible to the length of the changing signal period and the non-parametric estimation approach in the frequency domain. Effectiveness of estimations of the power quantities is demonstrated on the real signals of the short circuit in the power system.
COBISS.SI-ID: 12311636
A custom-made numerical model capable of conductive and radiative heat transfer is extensively presented in the paper. It was used for modeling of heat losses in open metal freezing-point cells. Besides the modeling results, experimental results are also presented that confirm the operation of the model. The main objective of the paper is to analyze and evaluate the temperature error due to radiative heat losses in glass cell. A custom-made numerical model capable of conductive and radiative heat transfer is extensively presented in the paper. It was used for modeling of heat losses in open metal freezing-point cells. Besides the modeling results, experimental results are also presented that confirm the operation of the model. The main objective of the paper is to analyze and evaluate the temperature error due to radiative heat losses in glass cell parts.
COBISS.SI-ID: 10944596
Digitalization as the main part of measurement consists of prefiltering,sampling, windowing, and quantization. In addition to this, the dynamics of the analogue-to-digital (A/D) conversion are also important. Here a tradeoff between the number of references for generating the reference levels and the number of steps of the conversion is presented.The differential tracking bbit A/D conversion gives better results than the classical A/D conversion with the successive approximation procedure, due to btimes more available sampling points, and the adaptive property of the A/D procedure that every previous approximation step to signal becomes the center of observation with an exponential increase in resolution in the new step. Considering together the systematic and the random errors in the signal parameters estimation, shows the advantage of the adaptive A/D conversion at lower values of the sampling ratio.
COBISS.SI-ID: 10206548
In this paper a procedure for evaluation of skin conductance measuring devices and acceptance criteria for evaluation of skin conductance measuring devices is proposed.The proposed procedure was tested by evaluating a wireless device.
COBISS.SI-ID: 10767956
In the paper novel method for direct measurement of air gap anomalies in direct-drive electrical motors is presented. The air gap anomalies can be of different types of eccentricity which may in extreme cases result in a mechanical rub between the stator and rotor, potentially leading to a motor breakdown. A novel measuring method is proposed using a sensory system integrated in a motor air gap to measure its width directly either in a static or dynamic state. It uses an optical sensory system to measure reflection of the infrared radiation between the rotor and stator. The method is validated by using a parallel measuring system employing an analogue Hall sensory system that measures the change in the magnetic-flux density. The two measuring systems are calibrated by comparing them to a reference laboratory measuring system consisting of a camera and lenses.
COBISS.SI-ID: 12414548