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The following fundamental concepts of measurement science have been briefly reported in this tutorial article: 1) The result of a measurement provides only incomplete knowledge of the measurand, whose true value remains unknown an...
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The following fundamental concepts of measurement science have been briefly reported in this tutorial article: 1) The result of a measurement provides only incomplete knowledge of the measurand, whose true value remains unknown and unknowable; 2) The uncertainty concept plays a key role in quantifying the incompleteness of the knowledge provided by the measurement result; and 3) A measurement result can be usefully employed only if the associated uncertainty is estimated and if it can be traced back to the appertaining standard; otherwise, it is a meaningless value. This tutorial has given a short review of the present practice for expressing and estimating uncertainty in measurement, based on the definitions and prescriptions given by the GUM.
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A simple technique is presented which utilizes dual-ridged waveguide to rectangular waveguide transitions to provide broadband material characterization measurements. Compared to a recently published technique which used dual-ridg...
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A simple technique is presented which utilizes dual-ridged waveguide to rectangular waveguide transitions to provide broadband material characterization measurements. Compared to a recently published technique which used dual-ridged waveguides, the proposed method significantly simplifies specimen preparation while maintaining measurement bandwidth. The behavior of the fields in the dual-ridged waveguide to rectangular waveguide transitions is briefly discussed. In addition, a brief discussion on the derivation of the theoretical scattering parameters, required for the extraction of permittivity and permeability of the material under test, is provided. Experimental material characterization results of a magnetic absorbing material are presented and analyzed to validate the proposed technique.
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Measurements underpin the engineering decisions that allow products to be designed, manufactured, operated, and maintained. Therefore, the quality of measured data needs to be systematically assured to allow decision makers to pro...
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Measurements underpin the engineering decisions that allow products to be designed, manufactured, operated, and maintained. Therefore, the quality of measured data needs to be systematically assured to allow decision makers to proceed with confidence. The use of standards is one way of achieving this. This paper explores the relevance of international documentary standards to the assessment of measurement system capability in High Value Manufacturing (HVM) Industry. An internal measurement standard is presented which supplements these standards and recommendations are made for a cohesive effort to develop the international standards to provide consistency in such industrial applications.
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Measurement uncertainty is a statistical parameter which describes the possible fluctuations of the result of a measurement. It is not a mere repeatability but it is at least as high as the intra-laboratory reproducibility. If it ...
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Measurement uncertainty is a statistical parameter which describes the possible fluctuations of the result of a measurement. It is not a mere repeatability but it is at least as high as the intra-laboratory reproducibility. If it is an attribute of a general analytical test procedure it is at least as high as the inter-laboratory reproducibility. Measurement uncertainty can be determined by the addition of the variances of the individual steps of the test procedure or by an approach which starts with one of the above-mentioned reproducibilities. Any measurement uncertainty should be kept low but it is objectionable to state too low a value, e.g. by falsely reporting mere repeatability data instead of properly determined uncertainty data. Some good working principles can help to obtain low measurement uncertainties.
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This paper is aimed at expressing the expanded combined measuring uncertainty of capacitive divider with concentrated capacitance on a high-voltage scale. The tested capacitive divider is constructed to have a minimal measuring un...
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This paper is aimed at expressing the expanded combined measuring uncertainty of capacitive divider with concentrated capacitance on a high-voltage scale. The tested capacitive divider is constructed to have a minimal measuring uncertainty. Measuring uncertainty of type A is expressed by means of the statistical processing of an experimentally determined random variable of pulse voltage amplitude and random variable of step voltage amplitude uncertainty budget of type B was derived from: 1) the influence of uncertainty values of a high-voltage and low-voltage capacitances on the transmission ratio; 2) the influence of frequency on the transmission ratio; and 3) measuring uncertainty type B of the used instrument. The experiments were performed under well-controlled conditions. Measuring uncertainty of type B for the first budget component is obtained theoretically using the Monte Carlo method, for the second budget component by using experimental-analytical method, while for the third budget component it is taken from the instructions manual of the manufacturer. The Gaussian distribution is attributed to the influential effects of the instruments measuring uncertainty type B. The results obtained show that most impact on measuring uncertainty of type B has the measuring uncertainty type B of the used instrument and the measuring uncertainty type B of divider by the influence of frequency. Values of expanded combined measuring uncertainty for 95\% of coverage probability are 5.2\% for frequencies equal to 50 MHz, 6.1\% for frequencies equal to 1 GHz, and 7.1\% for frequencies equal to 4 GHz. Comparing to our results for relative error of capacitive divider for measuring fast pulse voltages, it is shown that the tested capacitive divider has very good characteristics.
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This paper presents results of a trilateral comparison with a traveling ac voltage standard comprising a planar thin-film thermal converter. The ac–dc voltage transfer difference of the standard was measured at 1 V and at selecte...
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This paper presents results of a trilateral comparison with a traveling ac voltage standard comprising a planar thin-film thermal converter. The ac–dc voltage transfer difference of the standard was measured at 1 V and at selected frequencies from 20 Hz to 1 MHz against primary thermal ac voltage standards at the Silesian University of Technology, Istituto Nazionale di Ricerca Metrologica, and Trescal.
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This paper describes the realization of a new system for resistance scaling from 10 ${rm k}Omega$ to 100 ${rm T}Omega$. The resistance unit has been transferred from the quantum hall resistance (QHR) primary resistance standard to...
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This paper describes the realization of a new system for resistance scaling from 10 ${rm k}Omega$ to 100 ${rm T}Omega$. The resistance unit has been transferred from the quantum hall resistance (QHR) primary resistance standard to the resistance standard with a nominal value of 10 ${rm k}Omega$ by a cryogenic current comparator. For further transfer of the resistance unit from 10 ${rm k}Omega$ to 100 ${rm T}Omega$, Hamon transfer devices (Hamon networks) are used. For its complete realization five devices have been developed: 10–100–1000 ${rm k}Omega$, 1–10–100 ${rm M}Omega$, 0.1–1–10 ${rm G}Omega$, 10–100–1000 ${rm G}Omega$, and 1–10–100 ${rm T}Omega$. The first two devices have a single insulation, and the next three have a double isolation. In the transfer devices with the double insulation, triax-type connectors are used. All transfer devices have individual temperature stabilization within ${pm}{rm 0.01}^{circ}{rm C}$. In the paper, the factors influencing device accuracy have been described. The insulation leakage is recognized, and the error caused by it is calculated. The guarding network for the new design of Hamon transfer devices is pres- nted. Voltage coefficients of resistance and settling times of resistors used in these devices have been determined and discussed. Uncertainties for the Hamon transfer devices ratios have been calculated. Calibration results have been presented. The developed system is currently tested in the Central Office of Measures in Poland.
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The announcement of a revision of the Guide to the expression of uncertainty in measurement has renewed the debate about the topic of measurement uncertainty. In this paper the author, chairman of Working Group 1 of the Joint Comm...
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The announcement of a revision of the Guide to the expression of uncertainty in measurement has renewed the debate about the topic of measurement uncertainty. In this paper the author, chairman of Working Group 1 of the Joint Committee for Guides in Metrology, replies to the theses given in two recent papers by Semion Rabinovich. His opinions are personal, and are not necessarily shared by the JCGM/WG1. They are to be intended as a further contribution to the present discussion.
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This paper proposes and experimentally evaluates a method, which is able to measure the refrigeration capacity of compressors in extremely short times. Traditionally, the measurement of this parameter is done using specialized and...
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This paper proposes and experimentally evaluates a method, which is able to measure the refrigeration capacity of compressors in extremely short times. Traditionally, the measurement of this parameter is done using specialized and expensive test rigs and
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This article aims to assess specifically the effects of measurement noise on the evaluation of the flicker metrics defined in IEEE Standard 1789-2015. To this end, we compare two analytical approaches and Monte Carlo simulations w...
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This article aims to assess specifically the effects of measurement noise on the evaluation of the flicker metrics defined in IEEE Standard 1789-2015. To this end, we compare two analytical approaches and Monte Carlo simulations w.r.t. their ability to cope with natural bias of Flicker Percent and to estimate its measurement uncertainty. Two similar datasets from laboratory experiment representing luminous fluctuations of fluorescent light are considered. Recommendations on how to safely evaluate Percent Flicker and Flicker Index are given based on the hereby presented work.
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