The requirements of the ISO 10012 and recommendations “Guide to the Expression of Uncertainty in Measurement” are not applicable to all measurement methods and instruments. The specific features of their metrological confirmation are shown on the example of hardness measurement instruments. The proposed in the present paper methodological approach can be used in the process of correct methods of calibration and verification of hardness measurement instruments.
Methods of raising accuracy of temperature measurement channels of the measurement systems (MS) and computer-aided process control systems (CAPCS) are considered, as well as measurements resistance of thermometers with unified output signal which are the component parts of measurements of temperature for graduations, checks and metrological certifications for resistance of thermometers of MS and CAPCS.
Basing on the results of the described comparison the conception is built concerning the modulating functions method robustness in the case of calibration curve reconstruction problem using nonlinear model (1). Efficiency of the mentioned method expands the usability of quite monotonous nonlinear models like (1) for calibration curve parameters determination in a wide groupe of problems of calibration curve reconstruction on the base of an output of precise optical absorption gas analyzers.
The paper deals with constructional and technological problems connected with designing portable microprocessor-based calibrators for pressure and derived quantities. Microprocessor-based pressure calibrators, with accuracy of 0.05% FSO, designed within a dedicated project at Industrial Research Institute for Automation and Measurements are presented as an example. The discussed device is designated for calibration of pressure transducers directly on an industrial site, as well as for laboratory tests and measurements.
Mismatches in errors between the individual ADCs, more than the errors themselves, have been known to be the dominating cause of signal-distortion in certain systems like a Time-interleaved ADC, implemented using an array of ADCs. A new technique, using orthogonal sequences for effectively eliminating these mismatches, has been proposed in this paper as a scheme suitable for calibrating such an array of ADCs. Ease of implementation compared to currently existing techniques is the main advantage of this new scheme. Online calibration can be performed at the expense of some circuit overhead...
The large number of inspection features at dimensional measurements in the nano range entails a need for a lossless information flow along the process chain. Within the frame of fundamental research the concept of the closed process chain is adapted to the utilization at the NPM. Thereby, novel principles of knowledge distribution and novel inspection strategies are investigated. The latter focuses on the goal-oriented combination of overlapping measuring ranges of different scale of different sensors. In this regard the required sensor adaptability is also analysed. The paper deals with the...
In the field of coating thickness gauges till now the calibration method has been used, where with the coating thickness gauge the coating thickness, reproduced by the coating thickness standard has been measured. The difference between the coating thickness value reproduced by the coating thickness standard and the reading of the calibrated coating thickness gauge would give us in this case the correction in the mentioned calibration point. In the presentation a new calibration method of the coating thickness gauges will be described. A special measuring object with the changeable coating...
The Bayesian method of estimating is applied to the problem of recalibration of a measurement device. Recalibration of the device is considered within the Bayesian approach and earlier expressions for estimates of the interesting quantities are generalized to the case when the measurement device incorporates several calibrated reference quantities. The obtained new expressions take into account the result of a previous calibration of the reference quantities and give a posteriori estimates.
In the paper, a possibility of creation the operative methods of the remote no destroy control of layered natural and artificial media is considered. The behaviour peculiarities of the reflection factors for the ultra-wideband (UWB) signals of vertical and horizontal polarization are analysed at inclined falling on the control media. Results of UWB sounding by the vertical and horizontal polarized waves at small falling corners are used for the joint determination of electrophysical and structured properties of the upper layers of spreading media. Functional relationships between...
It is shown that available methods and devices for testing leakage of underwater pipelines do not allow to determine a defect location to high accuracy. In this view, it is suggested to receive the signals coming from acoustic emission by transducers of two-dimensional phased antenna array (PAA). It is demonstrated that an optimal way of PAA signal processing is the combination of pair multiplication with the subsequent algebraic summation of signals from several transducers. On the basis of the suggested method, the device PAL-121 was developed, which allows to determine a location of...